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1
Ghirardo, Andrea, Junfei Xie, Xunhua Zheng, Yuesi Wang, Rüdiger Grote, Katja Block, Jürgen Wildt, et al. "Urban stress-induced biogenic VOC emissions and SOA-forming potentials in Beijing." Atmospheric Chemistry and Physics 16, no. 5 (March 7, 2016): 2901–20. http://dx.doi.org/10.5194/acp-16-2901-2016.
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Abstract. Trees can significantly impact the urban air chemistry by the uptake and emission of reactive biogenic volatile organic compounds (BVOCs), which are involved in ozone and particle formation. Here we present the emission potentials of "constitutive" (cBVOCs) and "stress-induced" BVOCs (sBVOCs) from the dominant broadleaf woody plant species in the megacity of Beijing. Based on the municipal tree census and cuvette BVOC measurements on leaf level, we built an inventory of BVOC emissions, and assessed the potential impact of BVOCs on secondary organic aerosol (SOA) formation in 2005 and 2010, i.e., before and after realizing the large tree-planting program for the 2008 Olympic Games. We found that sBVOCs, such as fatty acid derivatives, benzenoids, and sesquiterpenes, constituted a significant fraction ( ∼ 40 %) of the total annual BVOC emissions, and we estimated that the overall annual BVOC budget may have doubled from ∼ 4.8 × 109 g C year−1 in 2005 to ∼ 10.3 × 109 g C year−1 in 2010 due to the increase in urban greening, while at the same time the emission of anthropogenic VOCs (AVOCs) decreased by 24 %. Based on the BVOC emission assessment, we estimated the biological impact on SOA mass formation potential in Beijing. Constitutive and stress-induced BVOCs might produce similar amounts of secondary aerosol in Beijing. However, the main contributors of SOA-mass formations originated from anthropogenic sources (> 90 %). This study demonstrates the general importance to include sBVOCs when studying BVOC emissions. Although the main problems regarding air quality in Beijing still originate from anthropogenic activities, the present survey suggests that in urban plantation programs, the selection of low-emitting plant species has some potential beneficial effects on urban air quality.
2
Yu, H., J. K. Holopainen, M. Kivimäenpää, A. Virtanen, and J. D. Blande. "Potential of Climate Change and Herbivory to Affect the Release and Atmospheric Reactions of BVOCs from Boreal and Subarctic Forests." Molecules 26, no. 8 (April 15, 2021): 2283. http://dx.doi.org/10.3390/molecules26082283.
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Compared to most other forest ecosystems, circumpolar boreal and subarctic forests have few tree species, and are prone to mass outbreaks of herbivorous insects. A short growing season with long days allows rapid plant growth, which will be stimulated by predicted warming of polar areas. Emissions of biogenic volatile organic compounds (BVOC) from soil and vegetation could be substantial on sunny and warm days and biotic stress may accelerate emission rates. In the atmosphere, BVOCs are involved in various gas-phase chemical reactions within and above forest canopies. Importantly, the oxidation of BVOCs leads to secondary organic aerosol (SOA) formation. SOA particles scatter and absorb solar radiation and grow to form cloud condensation nuclei (CCN) and participate in cloud formation. Through BVOC and moisture release and SOA formation and condensation processes, vegetation has the capacity to affect the abiotic environment at the ecosystem scale. Recent BVOC literature indicates that both temperature and herbivory have a major impact on BVOC emissions released by woody species. Boreal conifer forest is the largest terrestrial biome and could be one of the largest sources of biogenic mono- and sesquiterpene emissions due to the capacity of conifer trees to store terpene-rich resins in resin canals above and belowground. Elevated temperature promotes increased diffusion of BVOCs from resin stores. Moreover, insect damage can break resin canals in needles, bark, and xylem and cause distinctive bursts of BVOCs during outbreaks. In the subarctic, mountain birch forests have cyclic outbreaks of Geometrid moths. During outbreaks, trees are often completely defoliated leading to an absence of BVOC-emitting foliage. However, in the years following an outbreak there is extended shoot growth, a greater number of leaves, and greater density of glandular trichomes that store BVOCs. This can lead to a delayed chemical defense response resulting in the highest BVOC emission rates from subarctic forest in the 1–3 years after an insect outbreak. Climate change is expected to increase insect outbreaks at high latitudes due to warmer seasons and arrivals of invasive herbivore species. Increased BVOC emission will affect tropospheric ozone (O3) formation and O3 induced oxidation of BVOCs. Herbivore-induced BVOC emissions from deciduous and coniferous trees are also likely to increase the formation rate of SOA and further growth of the particles in the atmosphere. Field experiments measuring the BVOC emission rates, SOA formation rate and particle concentrations within and above the herbivore attacked forest stands are still urgently needed.
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Situ, S., A. Guenther, X. Wang, X. Jiang, A. Turnipseed, Z. Wu, G. Zhou, J. Bai, and X. Wang. "Impacts of seasonal and regional variability in biogenic VOC emissions on surface ozone in the Pearl River Delta region, China." Atmospheric Chemistry and Physics Discussions 13, no. 3 (March 13, 2013): 6729–77. http://dx.doi.org/10.5194/acpd-13-6729-2013.
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Abstract. In this study, the BVOC emissions in November 2010 over the Pearl River Delta (PRD) region in southern China have been estimated by the latest version of a Biogenic Volatile Organic Compound (BVOC) emission model (MEGAN v2.1). The evaluation of MEGAN performance at a representative forest site within this region indicates MEGAN can estimate BVOC emissions reasonably well in this region except overestimating isoprene emission in autumn for reasons that are discussed in this manuscript. Along with the output from MEGAN, the Weather Research and Forecasting model with chemistry (WRF-Chem) is used to estimate the impacts of BVOC emissions on surface ozone in the PRD region. The results show BVOC emissions increase the daytime ozone peak by ~3 ppb on average, and the max hourly impacts of BVOC emissions on the daytime ozone peak is 24.8 ppb. Surface ozone mixing ratios in the central area of Guangzhou-Foshan and the western Jiangmen are most sensitive to BVOC emissions BVOCs from outside and central PRD influence the central area of Guangzhou-Foshan and the western Jiangmen significantly while BVOCs from rural PRD mainly influence the western Jiangmen. The impacts of BVOC emissions on surface ozone differ in different PRD cities, and the impact varies in different seasons. Foshan and Jiangmen being most affected in autumn, result in 6.0 ppb and 5.5 ppb increases in surface ozone concentrations, while Guangzhou and Huizhou become more affected in summer. Three additional experiments concerning the sensitivity of surface ozone to MEGAN input variables show that surface ozone is more sensitive to landcover change, followed by emission factors and meteorology.
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Li, M., X. Huang, J. Li, and Y. Song. "Estimation of biogenic volatile organic compound (BVOC) emissions from the terrestrial ecosystem in China using real-time remote sensing data." Atmospheric Chemistry and Physics Discussions 12, no. 3 (March 2, 2012): 6551–92. http://dx.doi.org/10.5194/acpd-12-6551-2012.
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Abstract. Because of the high emission rate and reactivity, biogenic volatile organic compounds (BVOCs) play a significant role in the terrestrial ecosystems, human health, secondary pollution, global climate change and the global carbon cycle. Past estimations of BVOC emissions in China were based on outdated algorithms and coarsely resolved meteorological data, and there have been significant inconsistences between the land surface parameters of dynamic models and those of BVOC estimation models, leading to large inaccuracies in the estimated results. To refine BVOC emission estimations for China and to further explore the role of BVOCs in the atmosphere, we used the latest algorithms of MEGAN (Model of Emissions of Gases and Aerosols from Nature), with MM5 (the Fifth-Generation Mesoscale Model) providing highly resolved meteorological data, to estimate the biogenic emissions of isoprene (C5H8) and seven monoterpene species (C10H16) in 2006. Real-time MODIS (Moderate Resolution Imaging Spectroradiometer) data were introduced to update the land surface parameters and to improve the simulation performance of MM5, and to determine the influence of leaf area index (LAI) and leaf age deviation from standard conditions. In this study, the annual BVOC emissions for the whole country totaled 12.97 Tg C, a relevant value compared with past studies. Therein, the most important individual contributor was isoprene (9.36 Tg C yr−1), followed by α-pinene (1.24 Tg C yr−1) and β-pinene (0.84 Tg C yr−1). Due to the considerable regional disparity in plant distributions and meteorological conditions across China, BVOC emissions presented significant spatial and temporal variations. Spatially, isoprene emission was concentrated in South China, which is covered by large areas of broadleaf forests and shrubs. While Southeast China was the top-ranking contributor of monoterpenes, in which the dominant vegetation genera consist of evergreen coniferous forests. Temporally, BVOC emissions primarily occurred in July and August, with daily emissions peaking at about 13:00∼14:00 h (Beijing Time, BJT). In this study, we present an improved estimation of BVOC emissions, which provides important information for further exploration of the role of BVOCs in atmospheric processes.
5
Ghirardo, A., J. Xie, X. Zheng, Y. Wang, R. Grote, K. Block, J. Wildt, et al. "Urban stress-induced biogenic VOC emissions impact secondary aerosol formation in Beijing." Atmospheric Chemistry and Physics Discussions 15, no. 16 (August 27, 2015): 23005–49. http://dx.doi.org/10.5194/acpd-15-23005-2015.
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Abstract. Trees can significantly impact the urban air chemistry by the uptake and emission of reactive biogenic volatile organic compounds (BVOCs), which are involved in ozone and particle formation. Here we present the emission potentials of "constitutive" (cBVOCs) and "stress-induced" BVOCs (sBVOCs) from the dominant broadleaf woody plant species in the megacity of Beijing. Based on an inventory of BVOC emissions and the tree census, we assessed the potential impact of BVOCs on secondary particulate matter formation in 2005 and 2010, i.e., before and after realizing the large tree-planting program for the 2008 Olympic Games. We found that sBVOCs, such as fatty acid derivatives, benzenoids and sesquiterpenes, constituted a significant fraction (∼ 15 %) of the total annual BVOC emissions, and we estimated that the overall annual BVOC budget may have doubled from ∼ 3.6 × 109 g C year-1 in 2005 to ∼ 7.1 × 109 g C year-1 in 2010 due to the increase in urban greens, while at the same time, the emission of anthropogenic VOCs (AVOCs) could be lowered by 24 %. Based on our BVOC emission assessment, we estimated the biological impact on SOA mass formation in Beijing. Compared to AVOCs, the contribution of biogenic precursors (2–5 %) for secondary particulate matter in Beijing was low. However, sBVOCs can significantly contribute (∼ 40 %) to the formation of total secondary organic aerosol (SOA) from biogenic sources; apparently, their annual emission increased from 1.05 μg m-3 in 2005 to 2.05 μg m-3 in 2010. This study demonstrates that biogenic and, in particular, sBVOC emissions contribute to SOA formation in megacities. However, the main problems regarding air quality in Beijing still originate from anthropogenic activities. Nevertheless, the present survey suggests that in urban plantation programs, the selection of plant species with low cBVOC and sBVOC emission potentials have some possible beneficial effects on urban air quality.
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Situ, S., A. Guenther, X. Wang, X. Jiang, A. Turnipseed, Z. Wu, J. Bai, and X. Wang. "Impacts of seasonal and regional variability in biogenic VOC emissions on surface ozone in the Pearl River delta region, China." Atmospheric Chemistry and Physics 13, no. 23 (December 5, 2013): 11803–17. http://dx.doi.org/10.5194/acp-13-11803-2013.
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Abstract. This study investigated the impacts of seasonal and regional variability in biogenic volatile organic compounds (BVOCs) on surface ozone over the Pearl River delta (PRD) region in southern China in 2010 with the WRF–Chem/MEGAN (Weather Research and Forecasting coupled with Chemistry/Model of Emissions of Gases and Aerosols from Nature) modeling system. Compared to observations in the literature and this study, MEGAN tends to predict reasonable BVOC emissions in summer, but may overestimate isoprene emissions in autumn, even when the local high-resolution land-cover data and observed emission factors of BVOCs from local plant species are combined to constrain the MEGAN BVOC emissions model. With the standard MEGAN output, it is shown that the impact of BVOC emissions on the surface ozone peak is ~3 ppb on average with a maximum of 24.8 ppb over the PRD region in autumn, while the impact is ~10 ppb on average, with a maximum value of 34.0 ppb in summer. The areas where surface ozone is sensitive to BVOC emissions are different in autumn and in summer, which is primarily due to the change of prevailing wind over the PRD; nevertheless, in both autumn and summer, the surface ozone is most sensitive to the BVOC emissions in the urban area because the area is usually VOC-limited. Three additional experiments concerning the sensitivity of surface ozone to MEGAN input variables were also performed to assess the sensitivity of surface ozone to MEGAN drivers, and the results reveal that land cover and emission factors of BVOCs are the most important drivers and have large impacts on the predicted surface ozone.
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Panthee, Shristee, Louise A. Ashton, Akira Tani, Bimal Sharma, and Akihiro Nakamura. "Mechanical Branch Wounding Alters the BVOC Emission Patterns of Ficus Plants." Forests 13, no. 11 (November 16, 2022): 1931. http://dx.doi.org/10.3390/f13111931.
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Tree leaves emit biogenic volatile organic compounds (BVOCs) in response to mechanical wounding by insect folivores. However, BVOCs are also released from leaves in response to damage to other tree organs. In this study, we hypothesized that if trees utilize BVOCs to defend against leaf herbivory, BVOCs emitted in response to leaf wounding would be different from those emitted in response to other types of mechanical damage. To test this hypothesis, we measured BVOCs emitted from the leaves of four Ficus species in response to leaf-cutting, branch-cutting, leaf-branch-cutting, and control (constitutive BVOCs). We found that leaf-cutting triggered the emission of BVOCs, but their emission patterns were species-specific, and the overall BVOC composition did not significantly differ from that of constitutive BVOCs. In contrast, branch-cutting triggered the emission of many BVOCs, some known as parasitoid attractants and herbivore deterrents. Our study suggests that plant defense mediated by BVOCs is highly species-specific and not effective for attracting herbivore enemies when unrelated disturbances such as tree falls and windstorms occur. Additionally, we recommend avoiding ex situ BVOC sampling of cut plants, as this method alters BVOC emission patterns from both intact and damaged leaves.
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Li, De Wen, Yi Shi, Xing Yuan He, and Guang Yu Chi. "Seasonal Variations of BVOCs Emission from Ginkgo biloba Linn in Urban Area." Applied Mechanics and Materials 71-78 (July 2011): 2891–94. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.2891.
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In this study, seasonal biogenic volatile organic compound (BVOC) emission rates and emission patterns of Ginkgo biloba linn are estimated. The released volatiles were collected from branches onto cartridges filled with Tenax TA, and quantified by thermal desorption gas chromatography mass spectrometry (GC-MS). The result showed that the main BVOCs emitted from Ginkgo biloba linn were alkanes, aldehydes, alkenes, aromatic compounds, esters, terpenes and ketones. The total BVOC emission rate increased from May, and reached its maximum 27.96 μg C g-1dw h-1 in July, then decreased quickly. The emissions of α-pinene, isoprene, cyclohexane, methyl-cyclohexane and 2-methyl-hexane were significantly correlated to both temperature (p<0.05) and light (p<0.05).
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Makkonen, R., A. Asmi, V. M. Kerminen, M. Boy, A. Arneth, A. Guenther, and M. Kulmala. "BVOC-aerosol-climate interactions in the global aerosol-climate model ECHAM5.5-HAM2." Atmospheric Chemistry and Physics 12, no. 21 (November 2, 2012): 10077–96. http://dx.doi.org/10.5194/acp-12-10077-2012.
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Abstract. The biosphere emits volatile organic compounds (BVOCs) which, after oxidation in the atmosphere, can partition on the existing aerosol population or even form new particles. The large quantities emitted provide means for a large potential impact on both aerosol direct and indirect effects. Biogenic responses to atmospheric temperature change can establish feedbacks even in rather short timescales. However, due to the complexity of organic aerosol partitioning, even the sign of these feedbacks is of large uncertainty. We use the global aerosol-climate model ECHAM5.5-HAM2 to explore the effect of BVOC emissions on new particle formation, clouds and climate. Two BVOC emission models, MEGAN2 and LPJ-GUESS, are used. MEGAN2 shows a 25% increase while LPJ-GUESS shows a slight decrease in global BVOC emission between years 2000 and 2100. The change of shortwave cloud forcing from year 1750 to 2000 ranges from −1.4 to −1.8 W m−2 with 5 different nucleation mechanisms. We show that the change in shortwave cloud forcing from the year 2000 to 2100 ranges from 1.0 to 1.5 W m−2. Although increasing future BVOC emissions provide 3–5% additional CCN, the effect on the cloud albedo change is modest. Due to simulated decreases in future cloud cover, the increased CCN concentrations from BVOCs can not provide significant additional cooling in the future.
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Bachy, Aurélie, Marc Aubinet, Niels Schoon, Crist Amelynck, Bernard Bodson, Christine Moureaux, and Bernard Heinesch. "Are BVOC exchanges in agricultural ecosystems overestimated? Insights from fluxes measured in a maize field over a whole growing season." Atmospheric Chemistry and Physics 16, no. 8 (April 28, 2016): 5343–56. http://dx.doi.org/10.5194/acp-16-5343-2016.
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Abstract. Although maize is the second most important crop worldwide, and the most important C4 crop, no study on biogenic volatile organic compounds (BVOCs) has yet been conducted on this crop at ecosystem scale and over a whole growing season. This has led to large uncertainties in cropland BVOC emission estimations. This paper seeks to fill this gap by presenting, for the first time, BVOC fluxes measured in a maize field at ecosystem scale (using the disjunct eddy covariance by mass scanning technique) over a whole growing season in Belgium. The maize field emitted mainly methanol, although exchanges were bi-directional. The second most exchanged compound was acetic acid, which was taken up mainly in the growing season. Bi-directional exchanges of acetaldehyde, acetone and other oxygenated VOCs also occurred, whereas the terpenes, benzene and toluene exchanges were small, albeit significant. Surprisingly, BVOC exchanges were of the same order of magnitude on bare soil and on well developed vegetation, suggesting that soil is a major BVOC reservoir in agricultural ecosystems. Quantitatively, the maize BVOC emissions observed were lower than those reported in other maize, crops and grasses studies. The standard emission factors (SEFs) estimated in this study (231 ± 19 µg m−2 h−1 for methanol, 8 ± 5 µg m−2 h−1 for isoprene and 4 ± 6 µg m−2 h−1 for monoterpenes) were also much lower than those currently used by models for C4 crops, particularly for terpenes. These results suggest that maize fields are small BVOC exchangers in north-western Europe, with a lower BVOC emission impact than that modelled for growing C4 crops in this part of the world. They also reveal the high variability in BVOC exchanges across world regions for maize and suggest that SEFs should be estimated for each region separately.
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Chi, Yan Qi, and Shao Dong Xie. "Spatiotemporal Inventory of Biogenic Volatile Organic Compound Emissions in China Based on Vegetation Volume and Production." Advanced Materials Research 356-360 (October 2011): 2579–82. http://dx.doi.org/10.4028/www.scientific.net/amr.356-360.2579.
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To estimate the biogenic volatile organic compound (BVOC) emissions in China, this study collected data on vegetation volume, production and distribution, converted into leaf biomass and then used BVOC emission model. In 2003, the annual BVOC emission in China was 12.83 Tg, composed of 7.45 Tg isoprene, 2.23 Tg monoterpenes, and 3.14 Tg other VOCs (OVOCs). Emissions varied significantly among plant species, with contributions ordered as follows: forests > shrubs > crops > grasslands. Southern and northeastern China were the main sources of BVOC emissions. Significant seasonal variation was found with summer contributing the most.
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Cao, Jing, Shuping Situ, Yufang Hao, Shaodong Xie, and Lingyu Li. "Enhanced summertime ozone and SOA from biogenic volatile organic compound (BVOC) emissions due to vegetation biomass variability during 1981–2018 in China." Atmospheric Chemistry and Physics 22, no. 4 (February 21, 2022): 2351–64. http://dx.doi.org/10.5194/acp-22-2351-2022.
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Abstract. Coordinated control of fine particulate matter (PM2.5) and ozone (O3) has become a new and urgent issue for China's air pollution control. Biogenic volatile organic compounds (BVOCs) are important precursors of O3 and secondary organic aerosol (SOA) formation. China experienced a rapid increase in BVOC emissions as a result of increased vegetation biomass. We applied WRF-Chem3.8 coupling with MEGAN2.1 to conduct long-term simulations for impacts of BVOC emissions on O3 and SOA during 1981–2018, using the emission factors extrapolated by localized emission rates and annual vegetation biomass. In summer 2018, BVOC emissions were 9.91 Tg (in June), which led to an average increase of 8.6 ppb (16.75 % of the total) in daily maximum 8 h (MDA8) O3 concentration and 0.84 µg m−3 (73.15 % of the total) in SOA over China. The highest contribution to O3 is concentrated in the Great Khingan Mountains, Qinling Mountains, and most southern regions while in southern areas for SOA. Isoprene has the greatest contribution to O3, while monoterpene has the largest SOA production. BVOC emissions have distinguished impacts in different regions. The Chengdu–Chongqing (CC) region has the highest O3 and SOA generated by BVOCs, while the Beijing–Tianjin–Hebei (BTH) region has the lowest. From 1981 to 2018, the interannual variation of BVOC emissions caused by increasing leaf biomass resulted in O3 concentration increasing by 7.38 % at an average rate of 0.11 ppb yr−1 and SOA increasing by 39.30 % at an average rate of 0.008 µg m−3 yr−1. Due to the different changing trends of leaf biomass by region and vegetation type, O3 and SOA show different interannual variations. The Fenwei Plain (FWP), Yangtze River Delta (YRD), and Pearl River Delta (PRD) regions have the most rapid O3 increment, while the increasing rate of SOA in CC is the highest. BTH has the smallest enhancement in O3 and SOA concentration. This study will help to recognize the impact of historical BVOC emissions on O3 and SOA and further provide a reliable scientific basis for the precise prevention and control of air pollution in China.
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Jang, Youjung, Yangdam Eo, Meongdo Jang, Jung-Hun Woo, Younha Kim, Jae-Bum Lee, and Jae-Hyun Lim. "Impact of Land Cover and Leaf Area Index on BVOC Emissions over the Korean Peninsula." Atmosphere 11, no. 8 (July 30, 2020): 806. http://dx.doi.org/10.3390/atmos11080806.
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Biogenic volatile organic compound (BVOCs) emissions are the largest VOC emission source globally, and are precursors to ozone and secondary organic aerosols, both of which are strong, short-lived climate pollutants. BVOC emissions are usually estimated using the Model of Emissions of Gases and Aerosols from Nature (MEGAN), which requires Plant Functional Types (PFTs) and Leaf Area Indexes (LAIs) as inputs. Herein, the effects of refined input data on regional BVOC emission estimates are analyzed. For LAIs, lower resolution MODerate-resolution Imaging Spectroradiometer (MODIS), and higher spatio-temporal resolution Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM) LAI were generated. For PFTs, local land cover maps were developed, in addition to MODIS PFT. In South Korea, annual emissions of isoprene and monoterpenes in 2015 were estimated as 384 and 160 Gg/year, respectively, using STARFM LAI and Local PFT (Case 4). For North Korea, 340 Gg/year isoprene and 72 Gg/year monoterpenes emissions were estimated using STARFM LAI and MODIS PFT. These estimates were 14–110% higher than when using MODIS LAI and MODIS PFT (Case 1). Inter-comparison with satellite-based inverse isoprene emission estimates from GlobEmission shows 32% (North Korea) to 34% (South Korea) overestimation in bottom-up data. Our new vegetation inputs improve MEGAN performance and resulting BVOC emission estimations. Performance of Weather Research and Forecasting (WRF) meteorological modeling requires improvement, especially for solar radiation, to avoid overestimation of isoprene emissions.
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Karlsson, Tomas, Riikka Rinnan, and Thomas Holst. "Variability of BVOC Emissions from Commercially Used Willow (Salix spp.) Varieties." Atmosphere 11, no. 4 (April 7, 2020): 356. http://dx.doi.org/10.3390/atmos11040356.
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Willow (Salix spp.) trees are commonly used in short rotation coppices (SRC) to produce renewable energy. However, these plants are also known to emit high concentrations of biogenic volatile organic compounds (BVOCs), which have a large influence on air quality. Many different clones of commercially used Salix varieties exist today, but only a few studies have focused on BVOC emissions from these newer varieties. In this study, four varieties commercially propagated for biofuel production have been studied on a leaf-scale in the southern part of Sweden. The trees had either their first or second growing season, and measurements on BVOC emissions were done during the growing season in 2017 from the end of May to the beginning of September. Isoprene was the dominant emitted compound for all varieties but the average emission amongst varieties varied from 4.00 to 12.66 µg gdw−1 h−1. Average monoterpene (MT) (0.78–1.87 µg gdw−1 h−1) and sesquiterpene (SQT) emission rates (0.22–0.57 µg gdw−1 h−1) differed as well among the varieties. Besides isoprene, other compounds like ocimene, linalool and caryophyllene also showed a response to light but not for all varieties. Younger plants had several times higher emissions of non-isoprenoids (other VOCs) than the corresponding 1-year-old trees. The conclusions from this study show that the choice of variety can have a large impact on the regional BVOC emission budget. Genetics, together with stand age, should be taken into account when modelling BVOC emissions on a regional scale, for example, for air quality assessments.
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Jaakkola, Erica, Antje Gärtner, Anna Maria Jönsson, Karl Ljung, Per-Ola Olsson, and Thomas Holst. "Spruce bark beetles (Ips typographus) cause up to 700 times higher bark BVOC emission rates compared to healthy Norway spruce (Picea abies)." Biogeosciences 20, no. 4 (February 20, 2023): 803–26. http://dx.doi.org/10.5194/bg-20-803-2023.
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Abstract. Biogenic volatile organic compound (BVOC) emissions from trees subjected to biotic stress are higher compared to healthy trees, and they may also have a different compound composition. This in turn affects atmospheric chemistry and can lead to either positive or negative feedback to the climate. Climate change favors the abundance of the European spruce bark beetle (Ips typographus) which attacks the bark of Norway spruce (Picea abies) trees, causing induced BVOC emissions from the trees as a response to the insect stress. Here, results are reported from a study analyzing the difference in emission rates between healthy and bark-beetle-infested Norway spruce trees, changes in emission rates over time since the infestation started, and differences in emission rates from bark-beetle-drilled entry and exit holes. Bark chamber measurements on both healthy and infested trees were performed during the summer of 2019 at Hyltemossa and Norunda research stations in Sweden. The measurements showed that induced BVOC emissions following the bark beetle infestation were dominated by entry hole emissions in the early growing season and exit hole emissions in the later season. The results showed a significant difference in emission rates between healthy and infested trees during both seasons. The seasonal average standardized BVOC emission rate of healthy trees was 32 ± 52 µg m−2 h−1 (mean ± standard deviation), while the average standardized BVOC emission rates of infested trees were 6700 ± 6900 and 2000 ± 1300 µg m−2 h−1 during the early and late season respectively. BVOC emission rates were highest at the start of the infestation and decreased exponentially with time, showing induced emission rates for up to 1 year after which the emission rates were similar to those from healthy bark. Constitutive needle emission rates from healthy trees were found to be 11 times higher than bark emissions from healthy trees. However, when Norway spruce trees were infested, the bark emission rates were instead 6 to 20 times higher than the needle emissions, causing substantial increases in the total tree BVOC emission rate. This could lead to high impacts on atmospheric processes, specifically the formation of secondary organic aerosols, which have a higher yield from some monoterpene compounds, which increased from infested trees.
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Makkonen, R., A. Asmi, V. M. Kerminen, M. Boy, A. Arneth, A. Guenther, and M. Kulmala. "BVOC-aerosol-climate interactions in the global aerosol-climate model ECHAM5.5-HAM2." Atmospheric Chemistry and Physics Discussions 12, no. 4 (April 10, 2012): 9195–246. http://dx.doi.org/10.5194/acpd-12-9195-2012.
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Abstract. The biosphere emits volatile organic compounds (BVOCs) which, after oxidation in the atmosphere, can partition on the existing aerosol population or even form new particles. The large quantities emitted provide means for a large potential impact on both aerosol direct and indirect effects. Biogenic responses to atmospheric temperature change can establish feedbacks even in rather short timescales. However, due to the complexity of organic aerosol partitioning, even the sign of these feedbacks is of large uncertainty. We use the global aerosol-climate model ECHAM5.5-HAM2 to explore the effect of BVOC emissions on new particle formation, clouds and climate. Two BVOC emission models, MEGAN2 and LPJ-GUESS, are used to estimate the effect of BVOC-aerosol-climate coupling. The change of shortwave cloud forcing from year 1750 to 2000 ranges from −1.4 to −1.8 W m−2 with 5 different nucleation mechanisms. We show that the change in shortwave cloud forcing from the year 2000 to 2100 ranges from 1.0 to 1.5 W m−2. Although increasing future BVOC emissions provide 3–5% additional CCN, the effect on the cloud albedo change is modest. Due to simulated decreases in future cloud cover, the increased CCN concentrations from BVOCs can not provide significant additional cooling in the future.
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Guenther, Alex. "Biological and Chemical Diversity of Biogenic Volatile Organic Emissions into the Atmosphere." ISRN Atmospheric Sciences 2013 (June 18, 2013): 1–27. http://dx.doi.org/10.1155/2013/786290.
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Biogenic volatile organic compounds (BVOC) emitted by terrestrial ecosystems into the atmosphere play an important role in determining atmospheric constituents including the oxidants and aerosols that control air quality and climate. Accurate quantitative estimates of BVOC emissions are needed to understand the processes controlling the earth system and to develop effective air quality and climate management strategies. The large uncertainties associated with BVOC emission estimates must be reduced, but this is challenging due to the large number of compounds and biological sources. The information on the immense biological and chemical diversity of BVOC is reviewed with a focus on observations that have been incorporated into the MEGAN2.1 BVOC emission model. Strategies for improving current BVOC emission modeling approaches by better representations of this diversity are presented. The current gaps in the available data for parameterizing emission models and the priorities for future measurements are discussed.
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Matsunaga, S. N., A. B. Guenther, M. J. Potosnak, and E. C. Apel. "Emission of sunscreen salicylic esters from desert vegetation and their contribution to aerosol formation." Atmospheric Chemistry and Physics Discussions 8, no. 4 (July 16, 2008): 13619–32. http://dx.doi.org/10.5194/acpd-8-13619-2008.
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Abstract. Biogenic volatile organic compounds (BVOC) produced by plants are known to have an important role in atmospheric chemistry. However, our knowledge of the range of BVOCs produced by different plant processes is still expanding, and there remain poorly understood categories of BVOCs. In this study, emissions of a novel class of BVOC emissions were investigated in a desert region. Our study considered 8 species of common desert plants: blackbrush (Coleogyne ramosissima), desert willow (Chilopsis linearis), mesquite (Prosopis glandulosa), mondel pine (Pinus eldarica), pinyon pine (Pinus monophylla), cottonwood (Populus deltoides), saguaro cactus (Carnegiea gigantea) and yucca (Yucca baccata). The measurements focused on BVOCs with relatively high molecular weight (>C15) and/or an oxygenated functional group. Significantly high emission rates of two salicylic esters were found for blackbrush, desert willow and mesquite with emission rates of 1.4, 2.1 and 0.46 μgC dwg−1 h−1, respectively. The salicylic esters were identified as 2-ethylhexenyl salicylate (2-EHS) and 3,3,5-trimethylcyclohexenyl salicylate (homosalate) and are known as effective ultraviolet (UV) absorbers. We propose that the plants derive a protective benefit against UV radiation from the salicylic esters and that the emission process is driven by the physical evaporation of the salicylic esters due to the high ambient temperatures. In addition, the salicylic esters are predicted to be an effective precursor of secondary organic aerosol (SOA) because of their low vapor pressure due to a high number of carbon atoms (15 or 16) and the presence of three oxygen atoms. We estimated the contribution of the sunscreen esters themselves and their oxidation products on the SOA formation for the Las Vegas region using a BVOC emission model. The contribution was estimated to reach 90% of the biogenic SOA in the landscapes dominated by desert willow and mesquite and 25% in Las Vegas area.
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Baghi, R., D. Helmig, A. Guenther, T. Duhl, and R. Daly. "Contribution of flowering trees to urban atmospheric biogenic volatile organic compound emissions." Biogeosciences Discussions 9, no. 3 (March 15, 2012): 3145–72. http://dx.doi.org/10.5194/bgd-9-3145-2012.
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Abstract. Emissions of biogenic volatile organic compounds (BVOC) from urban trees during and after blooming were measured during spring and early summer 2009 in Boulder, Colorado. Air samples were collected onto solid adsorbent cartridges from branch enclosures on the tree species crabapple, horse chestnut, honey locust, and hawthorn. These species constitute ~65 % of the insect-pollinated fraction of the flowering tree canopy (excluding catkin-producing trees) from the street area managed by the City of Boulder. Samples were analyzed for C10–C15 BVOC by thermal desorption and gas chromatography coupled to a flame ionization detector and a mass spectrometer (GC/FID/MS). Identified emissions and emission rates from these four tree species during the flowering phase were found to vary over a wide range. Monoterpene emissions were identified for honey locust, horse chestnut and hawthorn. Sesquiterpene emissions were observed in horse chestnut and hawthorn samples. Crabapple flowers were found to emit significant amounts of benzyl alcohol and benzaldehyde. Floral BVOC emissions increased with temperature, generally exhibiting exponential temperature dependence. Changes in BVOC speciation during and after the flowering period were observed for every tree studied. Emission rates were significantly higher during the blooming compared to the vegetative state for crabapple and honey locust. Total normalized (30 °C) monoterpene emissions from honey locust were higher during flowering (5.26 μg Cg−1 h−1) than after flowering (1.23 μg Cg−1 h−1). The total normalized BVOC emission rate from crabapple (93 μg Cg−1 h−1) during the flowering period is of the same order as isoprene emissions from oak trees, which are among the highest BVOC emissions observed from plants to date. These findings illustrate that during the relatively brief springtime flowering period, floral emissions constitute by far the most significant contribution to the BVOC flux from these tree species, some of which are leafless at this time. Experimental results were integrated into the MEGAN biogenic emission model and simulations were performed to estimate the contribution of floral BVOC emissions to the total urban BVOC flux during the spring flowering period. The floral BVOC emitted during this three-month simulation are equivalent to 11 % of the cumulative monoterpene flux for the Boulder urban area.
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Li, De Wen, Yi Shi, Xing Yuan He, Guang Yu Chi, and Wei Huang. "Biogenic Volatile Organic Compounds Emit from Ginkgo (Ginkgo biloba linn)." Advanced Materials Research 113-116 (June 2010): 81–86. http://dx.doi.org/10.4028/www.scientific.net/amr.113-116.81.
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Emission rate of biogenic volatile organic compound (BVOC) released by ginkgo (Ginkgo biloba linn) was estimated from May to October 2007 in Shenyang, China. The released volatiles were collected from branches enclosed in sampling bags onto cartridges filled with Tenax-TA / Carboxen 1000 / Carbosieve SIII, and then quantified by thermal desorption gas chromatography. Isoprene was the main BVOC emitted from ginkgo in May and almost half BVOC emission was limonene during the period (from June to October). The BVOC emission rate increased from May, and reached maximum 42.21 μg g-1 dw h-1 in mid-June, then decreased quickly. Moreover, our study showed that the diurnal change of BVOC emission rate reached its maximum 32.31 µg•g-1dw•h-1 at 9:00 am, and 89.4% of the total emission was limonene. The emissions of isoprene and ocimene were correlated to both temperature (p<0.05) and light level (p<0.05).
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Matsunaga, S. N., A. B. Guenther, M. J. Potosnak, and E. C. Apel. "Emission of sunscreen salicylic esters from desert vegetation and their contribution to aerosol formation." Atmospheric Chemistry and Physics 8, no. 24 (December 11, 2008): 7367–71. http://dx.doi.org/10.5194/acp-8-7367-2008.
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Abstract. Biogenic volatile organic compounds (BVOC) produced by plants are known to have an important role in atmospheric chemistry. However, our knowledge of the range of BVOCs produced by different plant processes is still expanding, and there remain poorly understood categories of BVOCs. In this study, emissions of a novel class of BVOC emissions were investigated in a desert region. Our study considered 8 species of common desert plants: blackbrush (Coleogyne ramosissima), desert willow (Chilopsis linearis), mesquite (Prosopis glandulosa), mondel pine (Pinus eldarica), pinyon pine (Pinus monophylla), cottonwood (Populus deltoides), saguaro cactus (Carnegiea gigantea) and yucca (Yucca baccata). The measurements focused on BVOCs with relatively high molecular weight (>C15) and/or an oxygenated functional group. Significantly high emission rates of two salicylic esters were found for blackbrush, desert willow and mesquite with emission rates of 3.1, 1.0 and 4.8μgC dwg−1 h−1, respectively (dwg; dry weight of the leaves in gram). The salicylic esters were identified as 2-ethylhexenyl salicylate (2-EHS) and 3,3,5-trimethylcyclohexenyl salicylate (homosalate) and are known as effective ultraviolet (UV) absorbers. We propose that the plants derive a protective benefit against UV radiation from the salicylic esters and that the emission process is driven by the physical evaporation of the salicylic esters due to the high ambient temperatures. In addition, the salicylic esters are predicted to be an effective precursor of secondary organic aerosol (SOA) because they probably produce oxidation products that can condense onto the aerosol phase. We estimated the contribution of the sunscreen esters themselves and their oxidation products on the SOA formation for the Las Vegas area using a BVOC emission model. The contribution was estimated to reach 50% of the biogenic terpenoid emission in the landscapes dominated by desert willow and mesquite and 13% in the Las Vegas area. The contributions to biogenic SOA are likely to be higher due to the potentially high SOA yields of these compounds.
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Baghi, R., D. Helmig, A. Guenther, T. Duhl, and R. Daly. "Contribution of flowering trees to urban atmospheric biogenic volatile organic compound emissions." Biogeosciences 9, no. 10 (October 5, 2012): 3777–85. http://dx.doi.org/10.5194/bg-9-3777-2012.
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Abstract. Emissions of biogenic volatile organic compounds (BVOC) from urban trees during and after blooming were measured during spring and early summer 2009 in Boulder, Colorado. Air samples were collected onto solid adsorbent cartridges from branch enclosures on the tree species crabapple (Malus sp.), horse chestnut (Aesculus carnea, "Ft. McNair"), honey locust (Gleditsia triacanthos, "Sunburst"), and hawthorn (Crataegus laevigata, "Pauls Scarlet"). These species constitute ~ 65% of the insect-pollinated fraction of the flowering tree canopy (excluding catkin-producing trees) from the street area managed by the City of Boulder. Samples were analyzed for C10–C15 BVOC by thermal desorption and gas chromatography coupled to a flame ionization detector and a mass spectrometer (GC/FID/MS). Identified emissions and emission rates from these four tree species during the flowering phase were found to vary over a wide range. Monoterpene emissions were identified for honey locust, horse chestnut and hawthorn. Sesquiterpene emissions were observed in horse chestnut and hawthorn samples. Crabapple flowers were found to emit significant amounts of benzyl alcohol and benzaldehyde. Floral BVOC emissions increased with temperature, generally exhibiting exponential temperature dependence. Changes in BVOC speciation during and after the flowering period were observed for every tree studied. Emission rates were significantly higher during the blooming compared to the post-blooming state for crabapple and honey locust. The results were scaled to the dry mass of leaves and flowers contained in the enclosure. Only flower dry mass was accounted for crabapple emission rates as leaves appeared at the end of the flowering period. Total normalized (30 °C) monoterpene emissions from honey locust were higher during flowering (5.3 μgC g−1 h−1) than after flowering (1.2 μgC g−1 h−1). The total normalized BVOC emission rate from crabapple (93 μgC g−1 h−1) during the flowering period is of the same order as isoprene emissions from oak trees, which are among the highest BVOC flowering period floral emissions observed from plants to date. These findings illustrate that during the relatively brief springtime flowering period, floral emissions constitute by far the most significant contribution to the BVOC flux from these tree species, some of which are leafless at this time. Experimental results were integrated into the MEGAN biogenic emission model and simulations were performed to estimate the contribution of floral BVOC emissions to the total urban BVOC flux during the spring flowering period. The floral BVOC emitted during this three-month simulation are equivalent to 11% of the integrated monoterpene flux for the Boulder urban area.
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Tang, Jing, Guy Schurgers, Hanna Valolahti, Patrick Faubert, Päivi Tiiva, Anders Michelsen, and Riikka Rinnan. "Challenges in modelling isoprene and monoterpene emission dynamics of Arctic plants: a case study from a subarctic tundra heath." Biogeosciences 13, no. 24 (December 19, 2016): 6651–67. http://dx.doi.org/10.5194/bg-13-6651-2016.
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Abstract. The Arctic is warming at twice the global average speed, and the warming-induced increases in biogenic volatile organic compounds (BVOCs) emissions from Arctic plants are expected to be drastic. The current global models' estimations of minimal BVOC emissions from the Arctic are based on very few observations and have been challenged increasingly by field data. This study applied a dynamic ecosystem model, LPJ-GUESS, as a platform to investigate short-term and long-term BVOC emission responses to Arctic climate warming. Field observations in a subarctic tundra heath with long-term (13-year) warming treatments were extensively used for parameterizing and evaluating BVOC-related processes (photosynthesis, emission responses to temperature and vegetation composition). We propose an adjusted temperature (T) response curve for Arctic plants with much stronger T sensitivity than the commonly used algorithms for large-scale modelling. The simulated emission responses to 2 °C warming between the adjusted and original T response curves were evaluated against the observed warming responses (WRs) at short-term scales. Moreover, the model responses to warming by 4 and 8 °C were also investigated as a sensitivity test. The model showed reasonable agreement to the observed vegetation CO2 fluxes in the main growing season as well as day-to-day variability of isoprene and monoterpene emissions. The observed relatively high WRs were better captured by the adjusted T response curve than by the common one. During 1999–2012, the modelled annual mean isoprene and monoterpene emissions were 20 and 8 mg C m−2 yr−1, with an increase by 55 and 57 % for 2 °C summertime warming, respectively. Warming by 4 and 8 °C for the same period further elevated isoprene emission for all years, but the impacts on monoterpene emissions levelled off during the last few years. At hour-day scale, the WRs seem to be strongly impacted by canopy air T, while at the day–year scale, the WRs are a combined effect of plant functional type (PFT) dynamics and instantaneous BVOC responses to warming. The identified challenges in estimating Arctic BVOC emissions are (1) correct leaf T estimation, (2) PFT parameterization accounting for plant emission features as well as physiological responses to warming, and (3) representation of long-term vegetation changes in the past and the future.
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Williams, J. E., P. F. J. van Velthoven, and C. A. M. Brenninkmeijer. "Quantifying the uncertainty in simulating global tropospheric composition due to the variability in global emission estimates of Biogenic Volatile Organic Compounds." Atmospheric Chemistry and Physics Discussions 12, no. 11 (November 5, 2012): 28765–836. http://dx.doi.org/10.5194/acpd-12-28765-2012.
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Abstract. The emission of organic compounds from biogenic processes acts as an important source of trace gases in remote regions away from urban conurbations, and is likely to become more important in future decades due to the further mitigation of anthropogenic emissions that affect air quality and climate forcing. In this study we examine the contribution of biogenic volatile organic compounds (BVOCs) towards global tropospheric composition using the global 3-D chemistry transport model TM5 and the recently developed modified CB05 chemical mechanism. By comparing regional BVOC emission estimates we show that biogenic processes act as dominant sources for many regions and exhibit a large variability in the annually and seasonally integrated emission fluxes. By performing sensitivity studies we find that the contribution of BVOC species containing between 1 to 3 carbon atoms has an impact on the resident mixing ratios of tropospheric O3 and CO, accounting for ~3% and ~11% of the simulated global distribution, respectively. This is approximately a third of the cumulative effect introduced by isoprene and the monoterpenes. By examining an ensemble of 3-D global chemistry-transport simulations which adopt different global BVOC emission inventories we determine the associated uncertainty introduced towards simulating the composition of the troposphere for the year 2000. By comparing the model ensemble values against a~composite of atmospheric measurements we show that the effects on tropospheric O3 are limited to the lower troposphere (with an uncertainty between −2% to 10%), whereas that for tropospheric CO extends up to the upper troposphere (with an uncertainty of between 10 to 45%). Comparing the mixing ratios for low molecular weight alkenes in TM5 against surface measurements taken in Europe implies that the cumulative emission estimates are too low, regardless of the chosen BVOC inventory. This variability in the global distribution of CO due to BVOC emissions introduces an associated uncertainty in the tropospheric CO burden of ~11%, which impacts strongly on the oxidative capacity of the troposphere, introducing an uncertainty in the atmospheric lifetime of the greenhouse gas CH4 of ~3%. This study thus identifies the necessity of placing further constraints on non-CH4 global biogenic emission estimates in large-scale global atmospheric chemistry models.
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Williams, J. E., P. F. J. van Velthoven, and C. A. M. Brenninkmeijer. "Quantifying the uncertainty in simulating global tropospheric composition due to the variability in global emission estimates of Biogenic Volatile Organic Compounds." Atmospheric Chemistry and Physics 13, no. 5 (March 11, 2013): 2857–91. http://dx.doi.org/10.5194/acp-13-2857-2013.
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Abstract. The emission of organic compounds from biogenic processes acts as an important source of trace gases in remote regions away from urban conurbations, and is likely to become more important in future decades due to the further mitigation of anthropogenic emissions that affect air quality and climate forcing. In this study we examine the contribution of biogenic volatile organic compounds (BVOCs) towards global tropospheric composition using the global 3-D chemistry transport model TM5 and the recently developed modified CB05 chemical mechanism. By comparing regional BVOC emission estimates we show that biogenic processes act as dominant sources for many regions and exhibit a large variability in the annually and seasonally integrated emission fluxes. By performing sensitivity studies we find that the contribution of BVOC species containing between 1 to 3 carbon atoms has an impact on the resident mixing ratios of tropospheric O3 and CO, accounting for ~2.5% and ~10.8% of the simulated global distribution, respectively. This is approximately a third of the cumulative effect introduced by isoprene and the monoterpenes. By examining an ensemble of 3-D global chemistry transport simulations which adopt different global BVOC emission inventories we determine the associated uncertainty introduced towards simulating the composition of the troposphere for the year 2000. By comparing the model ensemble values against a composite of atmospheric measurements we show that the effects on tropospheric O3 are limited to the lower troposphere (with an uncertainty between −2% to 10%), whereas that for tropospheric CO extends up to the upper troposphere (with an uncertainty of between 10 to 45%). Comparing the mixing ratios for low molecular weight alkenes in TM5 against surface measurements taken in Europe implies that the cumulative emission estimates are too low, regardless of the chosen BVOC inventory. This variability in the global distribution of CO due to BVOC emissions introduces an associated uncertainty in the tropospheric CO burden of 11.4%, which impacts strongly on the oxidative capacity of the troposphere, introducing an uncertainty in the atmospheric lifetime of the greenhouse gas CH4 of ~3.3%. This study thus identifies the necessity of placing further constraints on non-CH4 global biogenic emission estimates in large-scale global atmospheric chemistry models.
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Timkovsky, J., P. Gankema, R. Pierik, and R. Holzinger. "A dynamic plant chamber system with downstream reaction chamber to study the effects of pollution on biogenic emissions." Atmospheric Measurement Techniques Discussions 6, no. 5 (October 22, 2013): 9005–36. http://dx.doi.org/10.5194/amtd-6-9005-2013.
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Abstract. A system of two dynamic plant chambers and a downstream reaction chamber has been set up to investigate the emission of biogenic volatile organic compounds (BVOC) and possible effects from pollutants such as ozone. The system can be used to compare BVOC emissions from two sets of differently treated plants, or to study the photochemistry of real plant emissions under polluted conditions without exposing the plants to pollutants. The main analytical tool is a proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS) which allows online monitoring of biogenic emissions and chemical degradation products. The identification of BVOCs and their oxidation products is aided by cryogenic trapping and subsequent in situ gas chromatographic analysis. The data presented in the paper demonstrates the good performance of the setup.
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Kleist, E., T. F. Mentel, S. Andres, A. Bohne, A. Folkers, A. Kiendler-Scharr, Y. Rudich, M. Springer, R. Tillmann, and J. Wildt. "Impact of heat stress on the emissions of monoterpenes, sesquiterpenes, phenolic BVOC and green leaf volatiles from several tree species." Biogeosciences Discussions 9, no. 7 (July 27, 2012): 9533–70. http://dx.doi.org/10.5194/bgd-9-9533-2012.
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Abstract. Changes in the biogenic volatile organic compound (BVOC) emissions from European beech, Palestine oak, Scots pine, and Norway spruce exposed to heat stress were measured in a laboratory setup. In general, heat stress decreased the de novo emissions of monoterpenes, sesquiterpenes and phenolic BVOC. Decreasing emission strength with heat stress was independent of the tree species and whether the de novo emissions being constitutive or induced by biotic stress. In contrast, heat stress induced emissions of green leaf volatiles. It also amplified the release of monoterpenes stored in resin ducts of conifers probably due to heat-induced damage of these resin ducts. The increased release of monoterpenes could be strong and long lasting. But, despite of such strong monoterpene emission pulses, the net effect of heat stress on BVOC emissions from conifers can be an overall decrease. In particular during insect attack on conifers the plants showed de novo emissions of sesquiterpenes and phenolic BVOC which exceeded constitutive monoterpene emissions from pools. The heat stress induced decrease of these de novo emissions was larger than the increased release caused by damage of resin ducts. We project that global change induced heat waves may cause increased BVOC emissions only in cases where the respective areas are predominantly covered with conifers that do not emit high amounts of sesquiterpenes and phenolic BVOC. Otherwise the overall effect of heat stress will be a decrease in BVOC emissions.
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Staudt, M., and L. Lhoutellier. "Monoterpene and sesquiterpene emissions from <i>Quercus coccifera</i> exhibit interacting responses to light and temperature." Biogeosciences Discussions 8, no. 3 (June 16, 2011): 5691–728. http://dx.doi.org/10.5194/bgd-8-5691-2011.
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Abstract. Light and temperature are known to be the most important environmental factors controlling biogenic volatile organic compound (BVOC) emissions from plants, but little is known about their interdependencies especially for BVOCs other than isoprene. We studied light responses at different temperatures and temperature responses at different light levels of foliar BVOC emissions, photosynthesis and chlorophyll fluorescence on Quercus coccifera, an evergreen oak widespread in Mediterranean shrublands. More than 50 BVOCs were detected in the emissions from Q. coccifera leaves most of them being isoprenoids plus a few green leaf volatiles (GLVs). Under standard conditions non-oxygenated monoterpenes (MT-hc) accounted for about 90 % of the total BVOC release (mean ± SD: 738 ± 378 ng m−2 projected leaf area s−1 or 13.1 ± 6.9 μg g−1 leaf dry weight h−1) and oxygenated monoterpenes (MT-ox) and sesquiterpenes (SQTs) accounted for the rest in about equal proportions. Except GLVs, emissions of all BVOCs responded positively to light and temperature. The light responses of MT and SQT emissions resembled that of CO2-assimilation and were little influenced by the assay temperature: at high assay temperature, MT-hc emissions saturated at lower light levels than at standard assay temperature and tended even to decrease in the highest light range. The emission responses to temperature showed mostly Arrhenius-type response curves, whose shapes in the high temperature range were clearly affected by the assay light level and were markedly different between isoprenoid classes: at non-saturating light, all isoprenoids showed a similar temperature optimum (~43 °C), but, at higher temperatures, MT-hc emissions decreased faster than MT-ox and SQT emissions. At saturating light, MT-hc emissions peaked already around 37 °C and rapidly dropped at higher temperatures, whereas MT-ox and SQT emissions strongly increased between 40 and 50 °C accompanied by a burst of GLVs. In all experiments, decreases of MT-hc emissions under high temperatures were correlated with decreases in CO2-assimilation and/or photosynthetic electron transport. We conclude that light and temperature can have interactive short-term effects on the quantity and quality of BVOC emissions from Q. coccifera through substrate limitations of MT biosynthesis occurring at temperatures supraoptimal for photosynthetic processes that are exacerbated by oxidative stress and membrane damages. Such interactive effects are likely to occur frequently during hot and dry summers and simulations made in this work showed that they may have important consequences for emission predictions.
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Staudt, M., and L. Lhoutellier. "Monoterpene and sesquiterpene emissions from <i>Quercus coccifera</i> exhibit interacting responses to light and temperature." Biogeosciences 8, no. 9 (September 28, 2011): 2757–71. http://dx.doi.org/10.5194/bg-8-2757-2011.
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Abstract. Light and temperature are known to be the most important environmental factors controlling biogenic volatile organic compound (BVOC) emissions from plants, but little is known about their interdependencies especially for BVOCs other than isoprene. We studied light responses at different temperatures and temperature responses at different light levels of foliar BVOC emissions, photosynthesis and chlorophyll fluorescence on Quercus coccifera, an evergreen oak widespread in Mediterranean shrublands. More than 50 BVOCs were detected in the emissions from Q. coccifera leaves most of them being isoprenoids plus a few green leaf volatiles (GLVs). Under standard conditions non-oxygenated monoterpenes (MT-hc) accounted for about 90% of the total BVOC release (mean ± SD: 738 ± 378 ng m−2 projected leaf area s−1 or 13.1 ± 6.9 μg g−1 leaf dry weight h−1) and oxygenated monoterpenes (MT-ox) and sesquiterpenes (SQTs) accounted for the rest in about equal proportions. Except GLVs, emissions of all BVOCs responded positively to light and temperature. The light responses of MT and SQT emissions resembled that of CO2-assimilation and were little influenced by the assay temperature: at high assay temperature, MT-hc emissions saturated at lower light levels than at standard assay temperature and tended even to decrease in the highest light range. The emission responses to temperature showed mostly Arrhenius-type response curves, whose shapes in the high temperature range were clearly affected by the assay light level and were markedly different between isoprenoid classes: at non-saturating light, all isoprenoids showed a similar temperature optimum (~43 °C), but, at higher temperatures, MT-hc emissions decreased faster than MT-ox and SQT emissions. At saturating light, MT-hc emissions peaked around 37 °C and rapidly dropped at higher temperatures, whereas MT-ox and SQT emissions strongly increased between 40 and 50 °C accompanied by a burst of GLVs. In all experiments, decreases of MT-hc emissions under high temperatures were correlated with decreases in CO2-assimilation and/or photosynthetic electron transport. We conclude that light and temperature can have interactive short-term effects on the quantity and quality of BVOC emissions from Q. coccifera through substrate limitations of MT biosynthesis occurring at temperatures supraoptimal for photosynthetic processes that are exacerbated by oxidative stress and membrane damages. Such interactive effects are likely to occur frequently during hot and dry summers and simulations made in this work showed that they may have important consequences for emission predictions.
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Kivimäenpää, Minna, Juha-Matti Markkanen, Rajendra P. Ghimire, Toini Holopainen, Martti Vuorinen, and Jarmo K. Holopainen. "Scots pine provenance affects the emission rate and chemical composition of volatile organic compounds of forest floor." Canadian Journal of Forest Research 48, no. 11 (November 2018): 1373–81. http://dx.doi.org/10.1139/cjfr-2018-0049.
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Scots pine (Pinus sylvestris L.) is an important source of biogenic volatile organic compounds (BVOCs) in the boreal zone. BVOC emission rate and profile affect air quality, climate forcing, plant stress tolerance, and thus the growing conditions of forests. BVOC emission profile of shoots and forest floor, as well as emission rates from forest floor, were studied in a latitudinal provenance experiment with 19-year-old Scots pine common garden in Central Finland. The provenances studied were Saaremaa (SAA, 58°22′), Korpilahti (KOR, 62°0′), Suomussalmi (SUO, 65°10′), and Muonio (MUO, 67°56′). A chemotype with high proportion of Δ-3-carene, terpinolene, sabinene, γ-terpinene, and α-terpinene was significantly more common for the southern SAA than the northern SUO and MUO provenances. A chemotype with high proportion of α-pinene, β-pinene, limonene, and myrcene was more common in the three northernmost provenances. The main compounds emitted by forest floor were α-pinene, Δ-3-carene, and camphene. Similarly to shoot emissions, forest floor emissions from SAA had highest proportion of Δ-3-carene. Average total VOC emission rate from forest floor was 50 μg·m−2·h−1 at the end of August. Total emission rates were 65% higher in KOR than in MUO. High emission rates were explained by the high amount of decomposing needle litter and low moss coverage.
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Saunier, Amélie, Elena Ormeño, Christophe Boissard, Henri Wortham, Brice Temime-Roussel, Caroline Lecareux, Alexandre Armengaud, and Catherine Fernandez. "Effect of mid-term drought on <i>Quercus pubescens</i> BVOCs' emission seasonality and their dependency on light and/or temperature." Atmospheric Chemistry and Physics 17, no. 12 (June 22, 2017): 7555–66. http://dx.doi.org/10.5194/acp-17-7555-2017.
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Abstract. Biogenic volatile organic compounds (BVOCs) emitted by plants represent a large source of carbon compounds released into the atmosphere, where they account for precursors of tropospheric ozone and secondary organic aerosols. Being directly involved in air pollution and indirectly in climate change, understanding what factors drive BVOC emissions is a prerequisite for modeling their emissions and predict air pollution. The main algorithms currently used to model BVOC emissions are mainly light and/or temperature dependent. Additional factors such as seasonality and drought also influence isoprene emissions, especially in the Mediterranean region, which is characterized by a rather long drought period in summer. These factors are increasingly included in models but only for the principal studied BVOC, namely isoprene, but there are still some discrepancies in estimations of emissions. In this study, the main BVOCs emitted by Quercus pubescens – isoprene, methanol, acetone, acetaldehyde, formaldehyde, MACR, MVK and ISOPOOH (these three last compounds detected under the same m∕z) – were monitored with a PTR-ToF-MS over an entire seasonal cycle during both in situ natural and amplified drought, which is expected with climate change. Amplified drought impacted all studied BVOCs by reducing emissions in spring and summer while increasing emissions in autumn. All six BVOCs monitored showed daytime light and temperature dependencies while three BVOCs (methanol, acetone and formaldehyde) also showed emissions during the night despite the absence of light under constant temperature. Moreover, methanol and acetaldehyde burst in the early morning and formaldehyde deposition and uptake were also punctually observed, which were not assessed by the classical temperature and light models.
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Wang, Hui, Qizhong Wu, Hongjun Liu, Yuanlin Wang, Huaqiong Cheng, Rongrong Wang, Lanning Wang, Han Xiao, and Xiaochun Yang. "Sensitivity of biogenic volatile organic compound emissions to leaf area index and land cover in Beijing." Atmospheric Chemistry and Physics 18, no. 13 (July 9, 2018): 9583–96. http://dx.doi.org/10.5194/acp-18-9583-2018.
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Abstract. The Beijing area has suffered from severe air pollution in recent years, including ozone pollution in the summer. In addition to the anthropogenic emissions inventory, understanding local ozone pollution requires a reliable biogenic volatile organic compound (BVOC) emission inventory. Forest coverage rose from 20.6 to 35.8 % from 1998 to 2013 in Beijing according to the National Forest Resource Survey (NFRS), and accurate representations of land cover for recent years is crucial for estimating BVOC emissions and their impacts on air quality. In this study, we established a high-resolution BVOC emission inventory in Beijing using the Model of Emissions of Gases and Aerosols from Nature (MEGAN) v2.1 with three independent leaf area index (LAI) products and three independent land cover products. Various combinations of the Global LAnd Surface Satellite (GLASS), Moderate-Resolution Imaging Spectroradiometer (MODIS) MCD15, and GEOland (GEO) v2 LAI datasets and the Finer Resolution Observation and Monitoring of Global Land Cover (FROM-GLC), MODIS MCD12Q1 plant functional type (PFT) products, and Climate Change Initiative Land Cover (CCI LC) products are used in five model sensitivity experiments (E1–E5), and the experiment using the FROM-GLC with the highest spatial resolution of 30 m and GLASS LAI products was treated as the baseline. These sensitivity calculations were driven by hourly, 3 km meteorological fields from the Weather Research and Forecasting (WRF) model. The following results were obtained: (1) according to the baseline estimate, the total amount of BVOC emissions is 75.9 Gg for the Beijing area, and isoprene, monoterpenes, sesquiterpenes and other VOCs account for 37.6, 14.6, 1.8 and 46 % of the total, respectively. Approximately three-quarters of BVOC emissions occur in the summer. (2) According to the sensitivity experiments, the LAI input does not significantly affect the BVOC emissions. Using MODIS MCD15Q1 and GEO v2 LAI led to slight declines of 2.6 and 1.4 %, respectively, of BVOC emissions in the same area. (3) The spatial distribution of PFTs from different inputs strongly influenced the spatial distribution of BVOC emissions. Furthermore, the cross-walking table for converting land cover classes to PFTs also has a strong impact on BVOC emissions; the sensitivity experiments showed that the estimate of BVOC emissions by CCI LC ranged from 42.1 to 70.2 Gg depending on the cross-walking table used.
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Bash, Jesse O., Kirk R. Baker, and Melinda R. Beaver. "Evaluation of improved land use and canopy representation in BEIS v3.61 with biogenic VOC measurements in California." Geoscientific Model Development 9, no. 6 (June 16, 2016): 2191–207. http://dx.doi.org/10.5194/gmd-9-2191-2016.
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Abstract. Biogenic volatile organic compounds (BVOC) participate in reactions that can lead to secondarily formed ozone and particulate matter (PM) impacting air quality and climate. BVOC emissions are important inputs to chemical transport models applied on local to global scales but considerable uncertainty remains in the representation of canopy parameterizations and emission algorithms from different vegetation species. The Biogenic Emission Inventory System (BEIS) has been used to support both scientific and regulatory model assessments for ozone and PM. Here we describe a new version of BEIS which includes updated input vegetation data and canopy model formulation for estimating leaf temperature and vegetation data on estimated BVOC. The Biogenic Emission Landuse Database (BELD) was revised to incorporate land use data from the Moderate Resolution Imaging Spectroradiometer (MODIS) land product and 2006 National Land Cover Database (NLCD) land coverage. Vegetation species data are based on the US Forest Service (USFS) Forest Inventory and Analysis (FIA) version 5.1 for 2002–2013 and US Department of Agriculture (USDA) 2007 census of agriculture data. This update results in generally higher BVOC emissions throughout California compared with the previous version of BEIS. Baseline and updated BVOC emission estimates are used in Community Multiscale Air Quality (CMAQ) Model simulations with 4 km grid resolution and evaluated with measurements of isoprene and monoterpenes taken during multiple field campaigns in northern California. The updated canopy model coupled with improved land use and vegetation representation resulted in better agreement between CMAQ isoprene and monoterpene estimates compared with these observations.
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Sindelarova, Katerina, Jana Markova, David Simpson, Peter Huszar, Jan Karlicky, Sabine Darras, and Claire Granier. "High-resolution biogenic global emission inventory for the time period 2000–2019 for air quality modelling." Earth System Science Data 14, no. 1 (January 26, 2022): 251–70. http://dx.doi.org/10.5194/essd-14-251-2022.
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Abstract. Biogenic volatile organic compounds (BVOCs) emitted from the terrestrial vegetation into the Earth's atmosphere play an important role in atmospheric chemical processes. Gridded information of their temporal and spatial distribution is therefore needed for proper representation of the atmospheric composition by the air quality models. Here we present three newly developed high-resolution global emission inventories of the main BVOC species including isoprene, monoterpenes, sesquiterpenes, methanol, acetone and ethene. Monthly mean and monthly averaged daily profile emissions were calculated by the Model of Emission of Gases and Aerosols from Nature (MEGANv2.1) driven by meteorological reanalyses of the European Centre for Medium-Range Weather Forecasts for the period of 2000–2019. The dataset CAMS-GLOB-BIOv1.2 is based on ERA-Interim meteorology (0.5∘ × 0.5∘ horizontal spatial resolution); the datasets CAMS-GLOB-BIOv3.0 and v3.1 were calculated with ERA5 (both 0.25∘ × 0.25∘ horizontal spatial resolution). Furthermore, European isoprene emission potential data were updated using high-resolution land cover maps and detailed information of tree species composition and emission factors from the EMEP MSC-W model system. Updated isoprene emissions are included in the CAMS-GLOB-BIOv3.1 dataset. The effect of annually changing land cover on BVOC emissions is captured by the CAMS-GLOB-BIOv3.0 as it was calculated with land cover data provided by the Climate Change Initiative of the European Space Agency (ESA-CCI). The global total annual BVOC emissions averaged over the simulated period vary between the datasets from 424 to 591 Tg (C) yr−1, with isoprene emissions from 299.1 to 440.5 Tg (isoprene) yr−1. Differences between the datasets and variation in their emission estimates provide the emission uncertainty range and the main sources of uncertainty, i.e. meteorological inputs, emission potential data and land cover description. The CAMS-GLOB-BIO time series of isoprene and monoterpenes were compared to other available data. There is a general agreement in an interannual variability in the emission estimates, and the values fall within the uncertainty range. The CAMS-GLOB-BIO datasets (CAMS-GLOB-BIOv1.2, https://doi.org/10.24380/t53a-qw03, Sindelarova et al., 2021a; CAMS-GLOB-BIOv3.0, https://doi.org/10.24380/xs64-gj42, Sindelarova et al., 2021b; CAMS-GLOB-BIOv3.1, https://doi.org/10.24380/cv4p-5f79, Sindelarova et al., 2021c) are distributed from the Emissions of atmospheric Compounds and Compilation of Ancillary Data (ECCAD) system (https://eccad.aeris-data.fr/, last access: June 2021).
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Bai, Jianhui. "O3 Concentration and Its Relation with BVOC Emissions in a Subtropical Plantation." Atmosphere 12, no. 6 (May 31, 2021): 711. http://dx.doi.org/10.3390/atmos12060711.
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An empirical model of O3 is developed using the measurements of emissions of biogenic volatile organic compounds (BVOCs), O3 concentration, global solar radiation, photosynthetically active radiation (PAR) and meteorological variables in a subtropical Pinus plantation, China, during 2013–2016. In view of the different structures of isoprene and monoterpenes, two empirical models of O3 concentration are developed, considering PAR absorption and scattering due to gases, liquids and particles (GLPs), as well as PAR attenuation caused by O3 and BVOCs. The estimated O3 is in agreement with the observations, and validation of the O3 empirical model is conducted. O3 concentrations are more sensitive to changes in PAR and water vapor than S/Q (horizontal diffuse to global solar radiation) and BVOC emissions. O3 is positive to changes in isoprene emission at low light and high GLPs, or negative at high light and low GLPs; O3 is negative to changes in monoterpene emissions. O3 are positive with the changes of PAR, water vapor and S/Q. It is suggested to control human-induced high BVOC emissions, regulate plant cutting, and reduce NOx and SO2 emissions more strictly than ever before. There are inverted U-shape interactions between O3 and its driving factors, and S/Q controls their turning points.
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Bash, J. O., K. R. Baker, and M. R. Beaver. "Evaluation of improved land use and canopy representation in BEIS v3.61 with biogenic VOC measurements in California." Geoscientific Model Development Discussions 8, no. 9 (September 21, 2015): 8117–54. http://dx.doi.org/10.5194/gmdd-8-8117-2015.
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Abstract. Biogenic volatile organic compounds (BVOC) participate in reactions that can lead to secondarily formed ozone and particulate matter (PM) impacting air quality and climate. BVOC emissions are important inputs to chemical transport models applied on local to global scales but considerable uncertainty remains in the representation of canopy parameterizations and emission algorithms from different vegetation species. The Biogenic Emission Inventory System (BEIS) has been used to support both scientific and regulatory model assessments for ozone and PM. Here we describe a new version of BEIS which includes updated input vegetation data and canopy model formulation for estimating leaf temperature and vegetation data on estimated BVOC. The Biogenic Emission Landuse Database (BELD) was revised to incorporate land use data from the Moderate Resolution Imaging Spectroradiometer (MODIS) land product and 2006 National Land Cover Database (NLCD) land coverage. Vegetation species data is based on the US Forest Service (USFS) Forest Inventory and Analysis (FIA) version 5.1 for years from 2002 to 2013 and US Department of Agriculture (USDA) 2007 census of agriculture data. This update results in generally higher BVOC emissions throughout California compared with the previous version of BEIS. Baseline and updated BVOC emissions estimates are used in Community Multiscale Air Quality Model (CMAQ) simulations with 4 km grid resolution and evaluated with measurements of isoprene and monoterpenes taken during multiple field campaigns in northern California. The updated canopy model coupled with improved land use and vegetation representation resulted in better agreement between CMAQ isoprene and monoterpene estimates compared with these observations.
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Zhang, Mingshuai, Chun Zhao, Yuhan Yang, Qiuyan Du, Yonglin Shen, Shengfu Lin, Dasa Gu, Wenjing Su, and Cheng Liu. "Modeling sensitivities of BVOCs to different versions of MEGAN emission schemes in WRF-Chem (v3.6) and its impacts over eastern China." Geoscientific Model Development 14, no. 10 (October 13, 2021): 6155–75. http://dx.doi.org/10.5194/gmd-14-6155-2021.
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Abstract. Biogenic volatile organic compounds (BVOCs) simulated by current air quality and climate models still have large uncertainties, which can influence atmospheric chemistry and secondary pollutant formation. These modeling sensitivities are primarily due to two sources. One originates from different treatments in the physical and chemical processes associated with the emission rates of BVOCs. The other is errors in the specification of vegetation types and their distribution over a specific region. In this study, the version of the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) updated by the University of Science and Technology of China (USTC version of WRF-Chem) from the public WRF-Chem(v3.6) is used. The modeling results over eastern China with different versions (v1.0, v2.0, v3.0) of the Model of Emissions of Gases and Aerosols from Nature (MEGAN) in WRF-Chem are examined or documented. Sensitivity experiments with these three versions of MEGAN and two vegetation datasets are conducted to investigate the difference of three MEGAN versions in modeling BVOCs and its dependence on the vegetation distributions. The experiments are also conducted for spring (April) and summer (July) to examine the seasonality of the modeling results. The results indicate that MEGAN v3.0 simulates the largest amount of biogenic isoprene emissions over eastern China. The different performance among MEGAN versions is primarily due to their different treatments of applying emission factors and vegetation types. In particular, the results highlight the importance of considering the sub-grid vegetation fraction in estimating BVOC emissions over eastern China, which has a large area of urbanization. Among all activity factors, the temperature-dependent factor dominates the seasonal change of activity factor in all three versions of MEGAN, while the different response to the leaf area index (LAI) change determines the difference among the three versions in seasonal variation of BVOC emissions. The simulated surface ozone concentration due to BVOCs can be significantly different (ranging from 1 to more than 10 ppbv in some regions) among the experiments with three versions of MEGAN, which is mainly due to their impacts on surface VOCs and NOx concentrations. Theoretically MEGAN v3.0 that is coupled with the land surface scheme and considers the sub-grid vegetation effect should overcome previous versions of MEGAN in WRF-Chem. However, considering uncertainties of retrievals and anthropogenic emissions over eastern China, it is still difficult to apply satellite retrievals of formaldehyde and/or limited sparse in situ observations to constrain the uncertain parameters or functions in BVOC emission schemes and their impacts on photochemistry and ozone production. More accurate vegetation distribution and measurements of biogenic emission fluxes and species concentrations are still needed to better evaluate and optimize models.
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Li, L., Y. Wang, Y. Zheng, and T. Chen. "ESTIMATION OF BVOC EMISSIONS IN GUANGZHOU AND ITS SPATIAL-TEMPORAL VARIATIONS: PRELIMINARY RESULTS FROM GLOBEIS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-3/W5 (October 29, 2018): 33–38. http://dx.doi.org/10.5194/isprs-archives-xlii-3-w5-33-2018.
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<p><strong>Abstract.</strong> Biogenic VOC emissions greatly exceed anthropogenic emissions and are regarded as significant precursors to secondary organic aerosol (SOA) and ozone. Using the Global Biosphere Emission and Interactions System (GloBEIS) model, 1<span class="thinspace"></span>&times;<span class="thinspace"></span>1<span class="thinspace"></span>km gridded and hourly BVOC emissions in Guangzhou were estimated for the year of 2012. This study used satellite-retrieved land cover data, cloud product and leaf area index (LAI), observed meteorological data and local emission rates for land cover types in South China. The result show that the total BVOC emission in Guangzhou, 2012 was 4.39<span class="thinspace"></span>kt and the average area emission was 5.93<span class="thinspace"></span>t/(km<sup>2</sup>&sdot;a), of which isoprene contributed about 55.7% (2.44<span class="thinspace"></span>kt)), monoterpenes about 11.9% (0.52<span class="thinspace"></span>kt) and OVOC about 32.4% (1.42<span class="thinspace"></span>kt). Emission factors of land cover types and correction parameters including LAI, wind speed and relative humidity have great effects on the estimation results of the model. BVOC emissions in Guangzhou exhibit a marked monthly and seasonal pattern with the peak emission in July to August and the lowest emission in January and are mainly distributed in the east-western of Conghua, the north of Zengcheng and the border of Huadu and Conghua, mostly covered by evergreen broadleaf forest with high emission factor, while areas of BVOC emission below 50<span class="thinspace"></span>kg/(km<sup>2</sup>&sdot;a) are distributed in highly urbanized areas like Tianhe, Yuexiu, Liwan and Haizhu district.</p>
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Han, Zhiyu, Yisheng Zhang, Houyong Zhang, Xuan Ge, Dasa Gu, Xiaohuan Liu, Jianhui Bai, et al. "Impacts of Drought and Rehydration Cycles on Isoprene Emissions in Populus nigra Seedlings." International Journal of Environmental Research and Public Health 19, no. 21 (November 5, 2022): 14528. http://dx.doi.org/10.3390/ijerph192114528.
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The volatile organic compounds emitted by plants significantly impact the atmospheric environment. The impacts of drought stress on the biogenic volatile organic compound (BVOC) emissions of plants are still under debate. In this study, the effects of two drought–rehydration cycle groups with different durations on isoprene emissions from Populus nigra (black poplar) seedlings were studied. The P. nigra seedlings were placed in a chamber that controlled the soil water content, radiation, and temperature. The daily emissions of isoprene and physiological parameters were measured. The emission rates of isoprene (Fiso) reached the maximum on the third day (D3), increasing by 58.0% and 64.2% compared with the controlled groups, respectively, and then Fiso significantly decreased. Photosynthesis decreased by 34.2% and 21.6% in D3 in the first and second groups, respectively. After rehydration, Fiso and photosynthesis recovered fully in two groups. However, Fiso showed distinct inconsistencies in two groups, and the recovery rates of Fiso in the second drought group were slower than the recovery rates of Fiso in the first groups. The response of BVOC emissions during the drought-rehydration cycle was classified into three phases, including stimulated, inhibited, and restored after rehydration. The emission pattern of isoprene indicated that isoprene played an important role in the response of plants to drought stress. A drought–rehydration model was constructed, which indicated the regularity of BVOC emissions in the drought–rehydration cycle. BVOC emissions were extremely sensitive to drought, especially during droughts of short duration. Parameters in computational models related to BVOC emissions of plants under drought stress should be continuously improved.
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Vella, Ryan, Matthew Forrest, Jos Lelieveld, and Holger Tost. "Isoprene and monoterpene simulations using the chemistry–climate model EMAC (v2.55) with interactive vegetation from LPJ-GUESS (v4.0)." Geoscientific Model Development 16, no. 3 (February 3, 2023): 885–906. http://dx.doi.org/10.5194/gmd-16-885-2023.
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Abstract. Earth system models (ESMs) integrate previously separate models of the ocean, atmosphere and vegetation into one comprehensive modelling system enabling the investigation of interactions between different components of the Earth system. Global isoprene and monoterpene emissions from terrestrial vegetation, which represent the most important source of volatile organic compounds (VOCs) in the Earth system, need to be included in global and regional chemical transport models given their major chemical impacts on the atmosphere. Due to the feedback of vegetation activity involving interactions with weather and climate, a coupled modelling system between vegetation and atmospheric chemistry is recommended to address the fate of biogenic volatile organic compounds (BVOCs). In this work, further development in linking LPJ-GUESS, a global dynamic vegetation model, to the atmospheric-chemistry-enabled atmosphere–ocean general circulation model EMAC is presented. New parameterisations are included to calculate the foliar density and leaf area density (LAD) distribution from LPJ-GUESS information. The new vegetation parameters are combined with existing LPJ-GUESS output (i.e. leaf area index and cover fractions) and used in empirically based BVOC modules in EMAC. Estimates of terrestrial BVOC emissions from EMAC's submodels ONEMIS and MEGAN are evaluated using (1) prescribed climatological vegetation boundary conditions at the land–atmosphere interface and (2) dynamic vegetation states calculated in LPJ-GUESS (replacing the “offline” vegetation inputs). LPJ-GUESS-driven global emission estimates for isoprene and monoterpenes from the submodel ONEMIS were 546 and 102 Tg yr−1, respectively. MEGAN determines 657 and 55 Tg of isoprene and monoterpene emissions annually. The new vegetation-sensitive BVOC fluxes in EMAC are in good agreement with emissions from the semi-process-based module in LPJ-GUESS. The new coupled system is used to evaluate the temperature and vegetation sensitivity of BVOC fluxes in doubling CO2 scenarios. This work provides evidence that the new coupled model yields suitable estimates for global BVOC emissions that are responsive to vegetation dynamics. It is concluded that the proposed model set-up is useful for studying land–biosphere–atmosphere interactions in the Earth system.
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Morichetti, Mauro, Sasha Madronich, Giorgio Passerini, Umberto Rizza, Enrico Mancinelli, Simone Virgili, and Mary Barth. "Comparison and evaluation of updates to WRF-Chem (v3.9) biogenic emissions using MEGAN." Geoscientific Model Development 15, no. 16 (August 16, 2022): 6311–39. http://dx.doi.org/10.5194/gmd-15-6311-2022.
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Abstract. Biogenic volatile organic compounds (BVOCs) emitted from the natural ecosystem are highly reactive and can thus impact air quality and aerosol radiative forcing. BVOC emission models (e.g., Model of Emissions of Gases and Aerosols from Nature – MEGAN) in global and regional chemical transport models still have large uncertainties in estimating biogenic trace gases because of uncertainties in emission activity factors, specification of vegetation type, and plant emission factors. This study evaluates a set of updates made to MEGAN v2.04 in the Weather Research and Forecasting model coupled with chemistry (WRF-Chem version 3.9). Our study considers four simulations for each update made to MEGAN v2.04: (i) a control run with no changes to MEGAN, (ii) a simulation with the emission activity factors modified following MEGAN v2.10, (iii) a simulation considering the changes to the plant functional type (PFT) emission factor, and (iv) a simulation with the isoprene emission factor calculated within the MEGAN module instead of being prescribed by the input database. We evaluate two regions, Europe and the southeastern United States, by comparing WRF-Chem results to ground-based monitoring observations in Europe (i.e., AirBase database) and aircraft observations obtained during the NOMADSS field campaign. We find that the updates to MEGAN v2.04 in WRF-Chem caused overpredictions in ground-based ozone concentrations in Europe and in isoprene mixing ratios compared to aircraft observations in the southeastern US. The update in emission activity factors caused the largest biases. These results suggest that further experimental and modeling studies should be conducted to address potential shortcomings in BVOC emission models.
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Toma, S., and S. Bertman. "The atmospheric potential of biogenic volatile organic compounds from needles of white pine (<i>Pinus strobus</i>) in Northern Michigan." Atmospheric Chemistry and Physics 12, no. 4 (February 29, 2012): 2245–52. http://dx.doi.org/10.5194/acp-12-2245-2012.
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Abstract. The key role that biogenic volatile organic compounds (BVOC) play in atmospheric chemistry requires a detailed understanding of how BVOC concentrations will be affected by environmental change. Large-scale screening of BVOC emissions from whole forest ecosystems is difficult with enclosure methods. Leaf composition of BVOC, as a surrogate for direct emissions, can more easily reflect the distribution of BVOC compounds in a forest. In this study, BVOC composition in needles of 92 white pine trees (Pinus strobus), which are becoming a large part of Midwest forests, are tracked for three summers at the University of Michigan Biological Station (UMBS). α-Pinene, the dominant terpene in all samples, accounts for 30–50% of all terpenes on a mole basis. The most abundant sesquiterpenoid was a C15 alcohol identified as germacrene D-4-ol. The relationship between limonene and total other monoterpenes shows two distinct trends in the population of these forests. About 14% (n = 13) of the trees showed high levels of limonene (up to 36% of the total BVOC) in the same trees every year. Assuming that needle concentrations scale with emission rate, we estimate that hydroxyl radical reactivity due to reaction with monoterpenes from white pine increases approximately 6% at UMBS when these elevated concentrations are included. We suggest that chemotypic variation within forests has the potential to affect atmospheric chemistry and that large-scale screening of BVOC can be used to study the importance of BVOC variation.
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Wang, Hui, Qizhong Wu, Alex B. Guenther, Xiaochun Yang, Lanning Wang, Tang Xiao, Jie Li, Jinming Feng, Qi Xu, and Huaqiong Cheng. "A long-term estimation of biogenic volatile organic compound (BVOC) emission in China from 2001–2016: the roles of land cover change and climate variability." Atmospheric Chemistry and Physics 21, no. 6 (March 29, 2021): 4825–48. http://dx.doi.org/10.5194/acp-21-4825-2021.
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Abstract. Satellite observations reveal that China has been leading the global greening trend in the past 2 decades. We assessed the impact of land cover change as well as climate variability on total biogenic volatile organic compound (BVOC) emission in China from 2001–2016. We found the greening trend in China is leading a national-scale increase in BVOC emission. The BVOC emission level in 2016 could be 11.7 % higher than that in 2001 because of higher tree cover fraction and vegetation biomass. On the regional scale, the BVOC emission level from 2013–2016 could be 8.6 %–19.3 % higher than that from 2001–2004 in hotspots including (1) northeastern China, (2) Beijing and its surrounding areas, (3) the Qin Mountains, (4) Yunnan Province, (5) Guangxi–Guangdong provinces, and (6) Hainan island because of the land cover change without considering the impact of climate variability. The comparison among different scenarios showed that vegetation changes resulting from land cover management are the main driver of BVOC emission change in China. Climate variability contributed significantly to interannual variations but not much to the changing trend during the study period. In the standard scenario, which considers both land cover change and climate variability, a statistically significant increasing trend can still be found in regions including Beijing and its surroundings, Yunnan Province, and Hainan island, and BVOC emission total amount in these regions from 2013–2016 is 11.0 %–17.2 % higher that from 2001–2004. We compared the long-term HCHO vertical columns (VC) from the satellite-based Ozone Monitoring Instrument (OMI) with the estimation of isoprene emission in summer. The results showed statistically significant positive correlation coefficients over the regions with high vegetation cover fractions. In addition, the isoprene emission and HCHO VC both showed statistically significant increasing trends in the south of China where these two variables have high positive correlation coefficients. This result may support our estimation of the variability and trends of BVOC emission in this region; however, the comparison still has large uncertainties since the chemical and physical processes, including transportation, diffusion and chemical reactions, were not considered. Our results suggest that the continued increase in BVOC will enhance the importance of considering BVOC when making policies for controlling ozone pollution in China along with ongoing efforts to increase the forest cover fraction.
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Yáñez-Serrano, A. M., A. C. Nölscher, J. Williams, S. Wolff, E. Alves, G. A. Martins, E. Bourtsoukidis, et al. "Diel and seasonal changes of biogenic volatile organic compounds within and above an Amazonian rainforest." Atmospheric Chemistry and Physics 15, no. 6 (March 25, 2015): 3359–78. http://dx.doi.org/10.5194/acp-15-3359-2015.
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Abstract. The Amazonian rainforest is a large tropical ecosystem, which is one of the last pristine continental terrains. This ecosystem is ideally located for the study of diel and seasonal behaviour of biogenic volatile organic compounds (BVOCs) in the absence of local human interference. In this study, we report the first atmospheric BVOC measurements at the Amazonian Tall Tower Observatory (ATTO) site, located in central Amazonia. A quadrupole proton-transfer-reaction mass spectrometer (PTR-MS), with seven ambient air inlets, positioned from near ground to about 80 m (0.05, 0.5, 4, 24, 38, 53 and 79 m above the forest floor), was deployed for BVOC monitoring. We report diel and seasonal (February–March 2013 as wet season and September 2013 as dry season) ambient mixing ratios for isoprene, monoterpenes, isoprene oxidation products, acetaldehyde, acetone, methyl ethyl ketone (MEK), methanol and acetonitrile. Clear diel and seasonal patterns were observed for all compounds. In general, lower mixing ratios were observed during night, while maximum mixing ratios were observed during the wet season (February–March 2013), with the peak in solar irradiation at 12:00 LT (local time) and during the dry season (September 2013) with the peak in temperature at 16:00 LT. Isoprene and monoterpene mixing ratios were the highest within the canopy with a median of 7.6 and 1 ppb, respectively (interquartile range (IQR) of 6.1 and 0.38 ppb) during the dry season (at 24 m, from 12:00 to 15:00 LT). The increased contribution of oxygenated volatile organic compounds (OVOCs) above the canopy indicated a transition from dominating forest emissions during the wet season (when mixing ratios were higher than within the canopy), to a blend of biogenic emission, photochemical production and advection during the dry season when mixing ratios were higher above the canopy. Our observations suggest strong seasonal interactions between environmental (insolation, temperature) and biological (phenology) drivers of leaf BVOC emissions and atmospheric chemistry. Considerable differences in the magnitude of BVOC mixing ratios, as compared to other reports of Amazonian BVOC, demonstrate the need for long-term observations at different sites and more standardized measurement procedures, in order to better characterize the natural exchange of BVOCs between the Amazonian rainforest and the atmosphere.
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Chen, Ying-Ju, Ya-Lun Huang, Yu-Han Chen, Shang-Tzen Chang, and Ting-Feng Yeh. "Biogenic Volatile Organic Compounds and Protein Expressions of Chamaecyparis formosensis and Chamaecyparis obtusa var. formosana Leaves under Different Light Intensities and Temperatures." Plants 11, no. 12 (June 8, 2022): 1535. http://dx.doi.org/10.3390/plants11121535.
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Both Chamaecyparis formosensis and C. obtusa var. formosana are representative cypresses of high economic value in Taiwan, the southernmost subtropical region where cypresses are found. Both species show differences of their habitats. To find out the effects of environmental factors on the CO2 assimilation rate and the biogenic volatile organic compound (BVOC) emission of both species, saplings from both species were grown under different light intensity and temperature regimes. The results indicated that the net CO2 assimilation rates and total BVOC emission rates of both species increased with increasing light intensity. C. formosensis showed a higher magnitude of change, but C. obtusa var. formosana had considerably increased sesquiterpenoid and diterpenoid emission in BVOC under high light intensity. Both species grown under higher temperatures had significantly lower BVOC emission rates. Proteomic analyses revealed that compared to C. formosensis saplings, C. obtusa var. formosana saplings had less differentially expressed proteins in terms of protein species and fold changes in response to the growth conditions. These proteins participated mainly in photosynthesis, carbon metabolism, amino acid and protein processing, signal transduction, and stress mechanisms. These proteins might be the major regulatory factors affecting BVOC emission of these two species under different environments.
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Schurgers, G., T. Hickler, P. A. Miller, and A. Arneth. "European emissions of isoprene and monoterpenes from the Last Glacial Maximum to present." Biogeosciences Discussions 6, no. 5 (September 3, 2009): 8805–49. http://dx.doi.org/10.5194/bgd-6-8805-2009.
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Abstract. Biogenic volatile organic compounds (BVOC), such as isoprene and monoterpenes, play an important role in atmospheric processes. BVOC species are oxidized in the atmosphere and influence levels of ozone. The less volatile amongst the BVOC and their oxidation products are important for the formation and growth of secondary biogenic aerosol. In this way, the earth's radiation balance is affected. Geographic distribution and temporal changes in BVOC emissions are highly uncertain. Here we assessed changes in emission patterns across Europe since the Last Glacial Maximum (LGM) with a dynamic vegetation model that reproduces European tree species distribution and in which a process-based algorithm for terpenoid production was incorporated. In a set of simulations the model was driven with paleoclimate anomalies and reconstructed CO2 concentrations. We quantified three main driving factors for the changes in emissions of isoprene and monoterpenes since the LGM: (1) the changes in climate, with temperature changes as the most important factor affecting plant physiology and terpenoid production in all plant species, (2) a change in species distribution related to the changes in climate, causing local shifts in emission characteristics of the vegetation, and (3) a change in CO2 concentration, causing opposing effects on the availability of different substrates for terpenoid production. The effect of atmospheric CO2 concentration is particularly uncertain, but sensitivity simulations showed an increase in European BVOC emissions in all sensitivity experiments irrespective of the use of a direct inhibition of terpenoid production by CO2. The effects of climate change on physiology and terpenoid production resulted in an overall relatively uniform increase of emissions in Europe over the simulation period, but regionally the effect of changes in species distribution and the related changes in emission capacities resulted in changes of emissions that can dominate over the physiology effects. This may have consequences for regional atmospheric chemistry simulations for the past, that have to rely on suitable geographic patterns of forest emissions.
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Schurgers, G., T. Hickler, P. A. Miller, and A. Arneth. "European emissions of isoprene and monoterpenes from the Last Glacial Maximum to present." Biogeosciences 6, no. 12 (December 3, 2009): 2779–97. http://dx.doi.org/10.5194/bg-6-2779-2009.
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Abstract. Biogenic volatile organic compounds (BVOC), such as isoprene and monoterpenes, play an important role in atmospheric processes. BVOC species are oxidized in the atmosphere and influence levels of ozone. The less volatile amongst the BVOC and their oxidation products are important for the formation and growth of secondary biogenic aerosol. In this way, the Earth's radiation balance is affected. Geographic distribution and temporal changes in BVOC emissions are highly uncertain. Here we assessed changes in emission patterns across Europe since the Last Glacial Maximum (LGM) with a dynamic vegetation model. This model reproduces European tree species distribution and includes a process-based algorithm for terpenoid production. In a set of simulations the model was driven with paleoclimate anomalies and reconstructed CO2 concentrations. We quantified three main driving factors for the changes in emissions of isoprene and monoterpenes since the LGM: (1) the changes in climate, with temperature changes as the most important factor affecting plant physiology and terpenoid production in all plant species, (2) a change in species distribution related to the changes in climate, causing local shifts in emission characteristics of the vegetation, and (3) a change in CO2 concentration, causing opposing effects on the availability of different substrates for terpenoid production. The effect of atmospheric CO2 concentration is particularly uncertain, but sensitivity simulations showed an increase in European BVOC emissions in all sensitivity experiments irrespective of the use of a direct inhibition of terpenoid production by CO2. The effects of climate change on physiology and terpenoid production resulted in an overall relatively uniform increase of emissions in Europe over the simulation period, but regionally the effect of changes in species distribution and the related changes in emission capacities resulted in changes of emissions that can dominate over the physiology effects. This may have consequences for regional atmospheric chemistry simulations for the past, that have to rely on suitable geographic patterns of forest emissions.
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Greenberg, J. P., A. Guenther, A. Turnipseed, X. Jiang, R. Seco, I. Filella, M. Estiraste, et al. "A tethered-balloon PTRMS sampling approach for rapid surveying of landscape-scale biogenic VOC fluxes." Atmospheric Measurement Techniques Discussions 7, no. 1 (January 31, 2014): 979–99. http://dx.doi.org/10.5194/amtd-7-979-2014.
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Abstract. To survey landscape-scale fluxes of biogenic gases, a 100 m Teflon tube was attached to a tethered balloon as a sampling inlet for a fast response Proton Transfer Reaction Mass Spectrometer (PTRMS). Along with meteorological instruments deployed on the tethered balloon and at 3 m and outputs from a regional weather model, these observations were used to estimate landscape scale biogenic volatile organic compound fluxes with two micrometeorological techniques: mixed layer variance and surface layer gradients. This highly mobile sampling system was deployed at four field sites near Barcelona to estimate landscape-scale BVOC emission factors in a relatively short period (3 weeks). The two micrometeorological techniques agreed within the uncertainty of the flux measurements at all four sites even though the locations had considerable heterogeneity in species distribution and complex terrain. The observed fluxes were significantly different than emissions predicted with an emission model using site-specific emission factors and land-cover characteristics. Considering the wide range in reported BVOC emission factors of VOCs for individual vegetation species (more than an order of magnitude), this flux estimation technique is useful for constraining BVOC emission factors used as model inputs.
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Eerdekens, G., L. Ganzeveld, J. Vilà-Guerau de Arellano, T. Klüpfel, V. Sinha, N. Yassaa, J. Williams, et al. "Flux estimates of isoprene, methanol and acetone from airborne PTR-MS measurements over the tropical rainforest during the GABRIEL 2005 campaign." Atmospheric Chemistry and Physics 9, no. 13 (July 1, 2009): 4207–27. http://dx.doi.org/10.5194/acp-9-4207-2009.
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Abstract. Tropical forests are a strong source of biogenic volatile organic compounds (BVOCs) to the atmosphere which can potentially impact the atmospheric oxidation capacity. Here we present airborne and ground-based BVOC measurements representative for the long dry season covering a large area of the northern Amazonian rainforest (6–3° N, 50–59° W). The measurements were conducted during the October 2005 GABRIEL (Guyanas Atmosphere-Biosphere exchange and Radicals Intensive Experiment with the Learjet) campaign. The vertical (35 m to 10 km) and diurnal (09:00–16:00) profiles of isoprene, its oxidation products methacrolein and methyl vinyl ketone and methanol and acetone, measured by PTR-MS (Proton Transfer Reaction Mass Spectrometry), have been used to empirically estimate their emission fluxes from the forest canopy on a regional scale. The mixed layer isoprene emission flux, inferred from the airborne measurements above 300 m, is 5.7 mg isoprene m−2 h−1 after compensating for chemistry and ~6.9 mg isoprene m−2 h−1 taking detrainment into account. This surface flux is in general agreement with previous tropical forest studies. Inferred methanol and acetone emission fluxes are 0.5 mg methanol m−2 h−1 and 0.35 mg acetone m−2 h−1, respectively. The BVOC measurements were compared with fluxes and mixing ratios simulated with a single-column chemistry and climate model (SCM). The inferred isoprene flux is substantially smaller than that simulated with an implementation of a commonly applied BVOC emission algorithm in the SCM.
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Sarkar, Chinmoy, Alex B. Guenther, Jeong-Hoo Park, Roger Seco, Eliane Alves, Sarah Batalha, Raoni Santana, et al. "PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest." Atmospheric Chemistry and Physics 20, no. 12 (June 22, 2020): 7179–91. http://dx.doi.org/10.5194/acp-20-7179-2020.
Full textAbstract:
Abstract. Biogenic volatile organic compounds (BVOCs) are important components of the atmosphere due to their contribution to atmospheric chemistry and biogeochemical cycles. Tropical forests are the largest source of the dominant BVOC emissions (e.g. isoprene and monoterpenes). In this study, we report isoprene and total monoterpene flux measurements with a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) using the eddy covariance (EC) method at the Tapajós National Forest (2.857∘ S, 54.959∘ W), a primary rainforest in eastern Amazonia. Measurements were carried out from 1 to 16 June 2014, during the wet-to-dry transition season. During the measurement period, the measured daytime (06:00–18:00 LT) average isoprene mixing ratios and fluxes were 1.15±0.60 ppb and 0.55±0.71 mg C m−2 h−1, respectively, whereas the measured daytime average total monoterpene mixing ratios and fluxes were 0.14±0.10 ppb and 0.20±0.25 mg C m−2 h−1, respectively. Midday (10:00–14:00 LT) average isoprene and total monoterpene mixing ratios were 1.70±0.49 and 0.24±0.05 ppb, respectively, whereas midday average isoprene and monoterpene fluxes were 1.24±0.68 and 0.46±0.22 mg C m−2 h−1, respectively. Isoprene and total monoterpene emissions in Tapajós were correlated with ambient temperature and solar radiation. Significant correlation with sensible heat flux, SHF (r2=0.77), was also observed. Measured isoprene and monoterpene fluxes were strongly correlated with each other (r2=0.93). The MEGAN2.1 (Model of Emissions of Gases and Aerosols from Nature version 2.1) model could simulate most of the observed diurnal variations (r2=0.7 to 0.8) but declined a little later in the evening for both isoprene and total monoterpene fluxes. The results also demonstrate the importance of site-specific vegetation emission factors (EFs) for accurately simulating BVOC fluxes in regional and global BVOC emission models.