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1
Ozdes, Mehmet. "The effect of climate and aerosol on crop production: a case study of central Asia." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48997.
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The effect of recent climate change in Central Asia poses a significant and potentially serious challenge to the region’s agricultural sector. An investigation of the aerosol-climate- crop yield correlation in this region is essential for a better understanding of the effect of aerosols and climate on Central Asian agriculture. Our goal is to investigate the linkages between aerosol, climate and major crop production (cotton, maize, wheat, and rice) in specified agricultural regions in the five Central Asian countries. Our approach is to perform the Pearson’s Correlation Coefficient analysis in order to observe the statistical correlation between crop yield, temperature, precipitation, and aerosol optical depth (AOD), for each indicated agricultural region in the selected countries. Besides, using NASA GIOVANNI website tools, we retrieve distribution maps and time series of temperature, precipitation and AOD to facilitate the analyses. The research shows that in some aspects, the relation between AOD, climate, and crop yield is different in Central Asia than in previous global or large scale research hypotheses. The statistical correlations vary not only across countries but also across agricultural regions. For example, in Kazakhstan, opposite correlations exist between precipitation and AOD in two different agricultural regions even though both regions are rain-fed. In the more arid countries (with lower rain rates) such as Turkmenistan and Uzbekistan, no correlation exists between crop production and temperature, precipitation, and AOD, while the less arid (with higher rain rate) countries (Kazakhstan, Kyrgyzstan, and Tajikistan) indicate a positive correlation.
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Kirillova, Elena N. "Dual isotope (13C-14C) Studies of Water-Soluble Organic Carbon (WSOC) Aerosols in South and East Asia." Doctoral thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-89161.
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Atmospheric aerosols may be emitted directly as particles (primary) or formed from gaseous precursors (secondary) from different natural and anthropogenic sources. The highly populated South and East Asia regions are currently in a phase of rapid economic growth to which high emissions of carbonaceous aerosols are coupled. This leads to generally poor air quality and a substantial impact of anthropogenic aerosols on the regional climate. However, the emissions of different carbon aerosol components are still poorly constrained. Water-soluble organic carbon (WSOC) is a large (20-80%) component of carbonaceous aerosols that can absorb solar light and enhance cloud formation, influencing both the direct and indirect climate effects of the aerosols. A novel method for carbon isotope-based studies, including source apportionment, of the WSOC component of ambient aerosols was developed and tested for recovery efficiency and the risk of contamination using both synthetic test substances and ambient aerosols (paper I). The application of this method for the source apportionment of aerosols in South and East Asia shows that fossil fuel input to WSOC is significant in both South Asia (about 17-23%) highly impacted by biomass combustion practices and in East Asia (up to 50%) dominated by fossil energy sources (papers II, III, IV). Fossil fraction in WSOC in the outflow from northern China is considerably larger than what has been measured in South Asia, Europe and USA (paper IV). A trend of enrichment in heavy stable carbon isotopes in WSOC with distance the particles have been transported from the source is observed in the South Asian region (papers II, III). Dual-isotope (Δ14C and δ13C) analysis demonstrates that WSOC is highly influenced by atmospheric aging processes.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Submitted.
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Huang, Yan. "Assessments of the Direct and Indirect Effects of Anthropogenic Aerosols on Regional Precipitation over East Asia Using a Coupled Regional Climate-Chemistry-Aerosol Model." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6870.
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An aerosol module is developed and coupled to a regional climate model to investigate the direct and indirect effect of anthropogenic aerosols (sulfate and carbonaceous aerosols) on climate with a focus on precipitation over East Asia. This fully coupled regional climate-chemistry-aerosol model is capable of understanding the interactions between the aerosol perturbation and climate change. The simulated aerosol spatial and seasonal distributions are generally consistent with the observations. The magnitude of the simulated total aerosol concentration and optical depth is about 2/3 of the observed value, suggesting the estimated climatic effects in this work are reasonable and conservative.
With the implementation of various aerosol effect, i.e., direct, semi-direct, 1st and 2nd indirect effect, the aerosols?impacts on climate are assessed over the region. The direct, semi-direct and 1st indirect effects generate a negative surface solar forcing, leading to a surface cooling, and the semi-direct effect also heats the atmosphere by BC absorption. This, in turn, increases the atmospheric stability and tends to inhibit the precipitation. The precipitation reduction is largest in the fall and winter, up to -10% with the inclusion of both direct and 1st indirect effects. The 2nd indirect effect using BH94 scheme produces a comparable magnitude in long-wave heating as the solar cooling, leading to the nighttime temperature warming of 0.5K, and a reduction in the diurnal temperature range. The precipitation reduction from the 2nd indirect effect strongly depends on the auto-conversion scheme, with about -30% in the fall and winter, and -15% in the spring and summer using BH94 scheme, while less than -5% using TC80 scheme. By allowing the feedbacks between aerosols and climate, the coupled model generally decreases the discrepancies between the model-simulated and observed precipitation and aerosols over the region. The EOF analysis of the climatological precipitation from last century over East Asia shows a decreasing mode in the EOF leading modes in the fall and winter, and is generally geographically consistent with the distribution of the model simulated precipitation reduction from anthropogenic aerosols.
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McNaughton, Cameron Stuart. "The spatial distribution and size evolution of particles in Asian outflow: the significance of primary and secondary aerosols during ACE-Asia and TRACE-P." Thesis, University of Hawaii at Manoa, 2003. http://hdl.handle.net/10125/6981.
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During the ACE-Asia and TRACE-P field campaigns aircraft measurements over the Yellow Sea, East China Sea and Sea of Japan revealed widespread secondary aerosol formation in the marine boundary layer. Similar observations were made throughout the day at the Gosan surface site on Jeju Island South Korea and aboard the American research vessel the RIV Ron Brown. Intercomparisons between the surface aerosol platforms and the airborne platforms show excellent agreement. Two post-frontal airmasses were characterized by concentrations of 3 -12 nm particles as high as 40,000 cm-3, and SO2 concentrations of 2 - 12 ppbv. Aerosol surface area in the marine boundary layer associated with regional air pollution and in one case, mineral dust, was in excess of 300 um2 cm-3 and as high as 1200 um2 cm-3. Thermodynamic profiles of the regional airmass suggest that steep gradients of aerosol surface area, relative humidity and temperature associated with elevated levels of SO2 created microphysical environments where new particle production is favoured. Although nucleation events were not observed directly, evidence for recently formed secondary aerosols were detected up to 48 hours after leaving the Asian landmass and were associated with SO2 concentrations in excess of 1 ppbv. Molar ratios of [NH4+]:(2[SO42-] + [NO3-]) in excess of 0.68 and volatility analysis showing partial neutralization of the nucleation and accumulation mode aerosols suggest a ternary nucleation mechanism involving H2SO4, H2O, and NH3. Growth rates of nucleation mode aerosols of 2.4 and 1.7 nm hr-1 were observed over a broad spatial extent during two consecutive flights. Based on the nucleation mode growth rates, the flux rate of vapour to the full size distribution suggests condensation rates of 2.4 +/- 1.2 x 106 molecules cm-3 s-1. Calculations of the coagulation rate for the nucleation mode particles suggest that most may be scavenged by the primary aerosol in less than 72 hours over the coastal waters of Asia before being transport out toward the Pacific Ocean.xi, 116 leaves
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BARCELAR, Jacqueline de Melo. "Efeitos da obesidade na distribuição e deposição pulmonar de aerossol e eficácia do heliox em mulheres obesas com e sem asma estável através da cintilografia pulmonar." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18516.
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Introdução: A obesidade é um fator de risco para asma, cujo tratamento principal consiste no uso dos aerossóis inalados. Entretanto, não existem dados na literatura a cerca do padrão de deposição de aerossol em indivíduos obesos não asmáticos e asmáticos. Além disso, existe uma lacuna no conhecimento do uso do heliox nesta população, pois este gás diminui a resistência ao fluxo aéreo e aumenta a ventilação. Objetivo: 1-Analisar a distribuição e deposição pulmonar e extrapulmonar de radioaerossol em mulheres adultas saudáveis com peso normal e obesas e 2-Analisar a distribuição e deposição pulmonar de radioaerossol, após inalação de radiofármaco carreado por oxigênio e heliox, em mulheres obesas não asmáticas e asmáticas, através de cintilografia pulmonar. Método: O estudo foi realizado em duas partes. A primeira um corte transversal com 29 mulheres: 15 obesas (IMC ≥30 kg/m2) e 14 com IMC =18,5–24,9 kg/m2. A segunda parte foi um ensaio clínico randomizado e crossover com mulheres obesas (IMC ≥30 kg/m2), 10 não asmáticas e 10 asmáticas estáveis. Todas as participantes inalaram 99mTc-DTPA tecnésio, com atividade de 37MBq (Megabequereis), associado a 0,9% de solução salina. Na primeira parte foi utilizado um nebulizador de membrana (NM) (Adágio, Dance Biopharm, San Francisco, CA) ativado pela respiração (volume solução=0,2mL). Na segunda parte foi utilizado o mesmo radiofármaco associado a 0.9% de solução salina e broncodilatadores, (volume solução= 1,5mL), utilizando NM (Aerogen® Solo, Aerogen Ltd, Galway, Irlanda) associado ao gás oxigênio ou heliox. Após a inalação, foram adquiridas as imagens cintilográficas de tórax posterior e anterior, face e equipamentos, com tempo 300 segundos para cada imagem. Para analisar as imagens foram criadas regiões de interesse (ROI) para regiões pulmonares e extra pulmonar. Resultados: No primeiro estudo, verificou-se maior deposição do radioaerossol nas vias aéreas superiores no grupo de obesas comparado com as de peso normal (9,54±3,68% versus 4,94±1,92%, p=0,002). Na comparação entre os grupos, os gradientes horizontal e vertical apresentaram padrão de distribuição semelhante, apesar de maior deposição pulmonar ter ocorrido em mulheres com peso normal (61,65 ± 7,37% versus 46,48 ± 8,94%, p<0,001). No segundo estudo, ao respirar oxigênio, o grupo de asmáticas apresentou 5% maior deposição pulmonar em comparação as não-asmáticas (p =0,016), e maior deposição do radioaerossol nas áreas centrais no pulmão direito (0,90±0,23 versus 0,71±1,13; p<0,05). Não foram observadas diferenças significativas na deposição pulmonar de radioaerossol entre os grupos com o uso do heliox, porém foi encontrada redução significativa do radioaerossol no nível de orofaringe nas não asmáticas (p=0,009) e aumento no filtro expiratório (p=0,023). Conclusão: Mulheres obesas demonstraram reduzida deposição pulmonar de radioaerossol e maior deposição na região da orofaringe quando comparadas com as mulheres com peso normal. Na segunda parte do estudo, as mulheres asmáticas apresentaram maior deposição pulmonar total e na região central de radioaerossol comparada com as mulheres obesas não asmáticas. Utilizando heliox, não foi observado aumento da deposição pulmonar de radioaerossol nas mulheres obesas não asmáticas e asmáticas. Entretanto, o heliox diminuiu a deposição de radioaerossol na orofaringe das mulheres obesas não asmáticas.
Introduction: Obesity is a risk factor for asthma the treatment is mainly with the use of inhaled aerosols. However, there is no data in the literature about the aerosol deposition pattern in obese subjects with and without asthma. Furthermore, there is a lack in knowledge regarding the use of heliox in this population, since the gas reduces the airflow resistance and increased ventilation. Objective: 1- Analyze radioaerosol distribution and deposition in pulmonary and extrapulmonary in healthy adult women with normal weight and obese, 2- Assess distribution and pulmonary and extrapulmonary deposition of radioaerosol, after radiolabel inhalation carried by oxygen and heliox in non-asthmatic and asthmatic obese women with stable asthma using pulmonary scintigraphy. Method: The study was conducted in two stages. The first was a cross-section with 28 women: 15 obese (BMI ≥30kg/m2) and 14 with BMI =18.5-24.9kg/m2. The second part was a randomized crossover trial, with obese women (BMI ≥ 30 kg/m2), 10 non-asthmatic and 10 asthmatic stable asthma. All subjects inhaled technetium 99m Tc-DTPA with 37 MBq (Megabecquerels) activity associated with 0.9% saline. In the first part was used a nebulizer membrane (NM) (Adage, Dance Biopharm, San Francisco, CA) activated by breath (solution volume = 0.2 mL). In the second part was used the same radiopharmaceutical associated with 0.9% saline and bronchodilators (solution volume =1.5mL) using NM (Aerogen® Solo, Aerogen Ltd, Galway, Ireland) associated with the gas oxygen or heliox. After inhalation were acquired the scintigraphic images of posterior and anterior chest, face and equipment, with time 300 seconds for each image. To analyze the images were created regions of interest (ROI) for pulmonary and extra pulmonary regions. Results: In the first study, a higher deposition radioaerossol upper airways in obese group compared with those of normal weight (9.54±3.68% versus 4.94±1.92%, p=0.002). Comparing the groups, the horizontal and vertical gradients showed similar distribution pattern, although greater lung deposition occurred in women with normal weight (61.65±7.37% versus 46.48±8.94%, P<0.001). In the second study, breathing oxygen, the asthmatic group had 5% higher lung deposition compared to non-asthmatics (p=0.016), and increased deposition of radioaerossol in the central areas in the right lung (0.90±0.23 versus 0.71±1.13; p<0.05). Significant differences in lung deposition of radioaerosol between groups with use of heliox, but found significant reduction of radioaerosol in the level of the oropharynx without asthma (p=0.009) and increase in expiratory filter were observed (p=0.023). In the second part of the study, asthmatic women showed higher total lung deposition and central radioaerossol compared with obese women without asthma. Using heliox was not observed increased lung deposition radioaerossol in obese women without asthma and asthma. However, heliox decreased deposition radioaerossol oropharyngeal obese women without asthma
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Ma, Yilin. "Developments and improvements to the particle-into-liquid-sampler (PILS) and its applications to Asian outflow studies." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-06072004-131244/unrestricted/ma%5Fyilin%5F200405%5Fphd.pdf.
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Kuhlmann, Julian, and Johannes Quaas. "How can aerosols affect the Asian summer monsoon?" Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-185964.
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The impact of aerosols above and around the Tibetan Plateau on the Asian Summer Monsoon during premonsoon seasons March-April-May 2007, 2008, and 2009 is investigated by means of remote sensing and radiative transfer modelling. Four source regions are found to be responsible for the high aerosol loading around the Tibetan Plateau: the Taklamakan Desert, the Ganges Plains, the Indus Plains, and the Arabian Sea. CALIPSO lidar satellite data, providing vertically resolved images of aerosols, shows aerosol concentrations to be highest in the lower 5 km of
the atmosphere with only little amounts reaching the Tibetan Plateau altitude. Using a radiative transfer model we find that aerosol plumes reduce shortwave radiation throughout the Monsoon region in the seasonal average by between 20 and 30 W/m2. Peak shortwave heating in the lower troposphere reaches 0.2 K/day. In higher layers this shortwave heating is partly balanced by longwave cooling. Although
high-albedo surfaces, such as deserts or the Tibetan Plateau,
increase the shortwave heating by around 10%, the overall effect is strongest close to the aerosol sources. A strong elevated heating which could influence large-scale monsoonal circulations as suggested by previous studies is not found.
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Su, Xiaoli. "Analyses of aerosol characteristics over east Asia using POLDER observations." Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10087/document.
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Cette thèse a pour objectif principal de fournir une analyse de distribution et de la variabilité des aérosols en Asie à partir des observations satellitaires de PARASOL au-dessus des continents. Nous avons d’abord comparé les épaisseurs optiques en aérosols (AOD pour aerosol optical depth) PARASOL à celles du mode fin (particules de rayon ≤ 0.30 µm) calculées à partir des inversions des mesures photométriques de 14 sites AERONET. La qualité des corrélations obtenues démontre la bonne sensibilité des restitutions de PARASOL à la plus fine fraction des aérosols, qui proviennent principalement de sources anthropiques. Nous avons analysé les caractéristiques des distributions en aérosols à partir de quatre années de données PARASOL (mars 2005 à février 2009). Notre étude a montré que la distribution spatiale des aérosols du mode fin en Asie était étroitement liée à celle des activités humaines. Nous avons également mis en évidence une forte variabilité saisonnière de l’AOD du mode fin qui diffère selon les zones géographiques. Enfin, nous avons analysé la variabilité interannuelle sur la période 2003-2009 en été au nord de la Chine, en particulier dans la région de Beijing, et dans le contexte des réductions d’émissions des jeux olympiques de l’été 2008. Nous avons montré que les AOD du mode fin sont relativement élevées au cours des étés 2003, 2007 et 2008. Les variations interannuelles des AOD moyennes mensuelles ont montré que la variabilité était maximale en juin et similaire à celle de juillet, à la différence de celle observée en août. Dans cette étude, les AOD mesurées par AERONET dans la région de Beijing en été sont utilisées comme références et également analyséesThis thesis is devoted to analyze aerosol distribution and variability over East Asia based on PARASOL aerosol products over land. We first compared PARASOL Aerosol Optical Depth (AOD) with fine mode AOD (particles radius ≤ 0.30 μm) computed from AERONET (Aerosol Robotic Network) inversions over 14 sites. The rather good correlation observed over land demonstrates the remarkable sensitivity of PARASOL retrievals to the smaller fraction of fine particles, mostly originating from anthropogenic sources. We analyzed the characteristics and seasonal variation of aerosol distribution over East Asia considering four years of PARASOL Level 2 data (March 2005 to February 2009). Our study shows that the spatial distribution of fine-mode aerosols over East Asia, as retrieved from PARASOL, is highly associated with human activities. Our work also evidenced a strong variability of seasonal fine-mode AOD patterns with geographical locations. Finally, the inter-annual variation during 2003-2009 periods of summer fine-mode AOD over North China, in particular the Beijing City region, was analyzed for the contribution to evaluating the regional impact of emission reduction enforced in Beijing during the 2008 Olympic Summer Games. We found that summer average of fine-mode AOD exhibited relatively higher values in 2003, 2007 and 2008. The inter-annual variation patterns of monthly averaged AOD (June to August) shows that June generally exhibits the strongest variation and varies similar to July, but differs from August. As reference, measured total AOD and fine mode AOD computed from AERONET inversions in summer are also discussed for the Beijing City region
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Salzmann, Marc, Ribu Cherian, and Hagen Weser. "Robust response of Asian summer monsoon to anthropogenic aerosols in CMIP5 models." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-197058.
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The representation of aerosol processes and the skill in simulating the Asian summer monsoon vary widely across climate models. Yet, for the second half of the twentieth century, the models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) show a robust decrease of average precipitation in the South and Southeast Asian (SSEA) continental region due to the increase of anthropogenic aerosols. When taking into account anthropogenic aerosols as well as greenhouse gases (GHGs), the 15 CMIP5 models considered in this study yield an average June–September precipitation least squares linear trend of −0.20 ± 0.20mm d−1 (50 years)−1, or −2.9%, for all land points in the SSEA region (taken from 75 to
120◦E and 5 to 30◦N) in the years from 1950 to 1999 (multimodel average ± one standard deviation) in spite of an increase in the water vapor path of +0.99 ± 0.65 kg m−2 (50 years)−1 (+2.5%). This negative precipitation trend differs markedly from the positive precipitation trend of +0.29 ± 0.14mm d−1 (50 years)−1, or +4.1%, which is computed for GHG forcing only. Taking into account aerosols both
decreases the water vapor path and slows down the monsoon circulation as suggested by several previous studies. At smaller scales, however, internal variability makes attributing observed precipitation changes to anthropogenic aerosols more difficult. Over Northern Central India (NCI), the spread between precipitation trends from individual model realizations is generally comparable in magnitude to simulated changes due to aerosols, and the model results suggest that the observed drying in NCI might in part be explained by internal variability.
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Salzmann, Marc, Ribu Cherian, and Hagen Weser. "Robust response of Asian summer monsoon to anthropogenic aerosols in CMIP5 models." American Geophysical Union (AGU), 2014. https://ul.qucosa.de/id/qucosa%3A14474.
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The representation of aerosol processes and the skill in simulating the Asian summer monsoon vary widely across climate models. Yet, for the second half of the twentieth century, the models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) show a robust decrease of average precipitation in the South and Southeast Asian (SSEA) continental region due to the increase of anthropogenic aerosols. When taking into account anthropogenic aerosols as well as greenhouse gases (GHGs), the 15 CMIP5 models considered in this study yield an average June–September precipitation least squares linear trend of −0.20 ± 0.20mm d−1 (50 years)−1, or −2.9%, for all land points in the SSEA region (taken from 75 to
120◦E and 5 to 30◦N) in the years from 1950 to 1999 (multimodel average ± one standard deviation) in spite of an increase in the water vapor path of +0.99 ± 0.65 kg m−2 (50 years)−1 (+2.5%). This negative precipitation trend differs markedly from the positive precipitation trend of +0.29 ± 0.14mm d−1 (50 years)−1, or +4.1%, which is computed for GHG forcing only. Taking into account aerosols both
decreases the water vapor path and slows down the monsoon circulation as suggested by several previous studies. At smaller scales, however, internal variability makes attributing observed precipitation changes to anthropogenic aerosols more difficult. Over Northern Central India (NCI), the spread between precipitation trends from individual model realizations is generally comparable in magnitude to simulated changes due to aerosols, and the model results suggest that the observed drying in NCI might in part be explained by internal variability.
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Xi, Xin. "Examination of mineral dust variability and linkages to climate and land-cover/land-use change over Asian drylands." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53433.
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Large uncertainties remain in estimating the anthropogenic fraction of mineral dust and the climatic impact of dust aerosol, partly due to a poor understanding of the dust source dynamics under the influence of climate variability and human-induced land-cover/land-use change (LCLUC). So far, the dust dynamics and linkage to climate and LCLUC in Central Asia have received little attention from the aerosol research community. This thesis comprises a comprehensive study of the dust dynamics in Central Asia focusing on 1) the seasonality of erosion threshold and dust emission affected by soil moisture, vegetation phenology and surface roughness, 2) the dust interannual variability and connections with large-scale climate variation (ENSO) through effects on the atmospheric circulation, precipitation, vegetation dynamics and drought, and 3) the impact of dust aerosol on surface radiative balance and photosynthetically active radiation, and possible effect on dryland ecosystems. A coupled dust model and multi-year ground and satellite observations of dust frequency, dust loading, and atmospheric and land conditions are used in this study. We find the threshold friction velocity significantly varies in space and time in response to soil moisture seasonality, surface roughness heterogeneity and vegetation phenology. Spring is associated a higher threshold friction velocity than summer, due to wetter soils and more vegetation cover. As a result, although more frequent strong winds occur during spring, spring dust emission is less than summer by 46.8% (or 60.4 Mt). Ignoring the dependence of the threshold friction velocity on the surface characteristics leads to biased spatial distribution and seasonality of dust emission. There is a strong linkage between dust and ENSO in Central Asia: La Nina years produce drought condition and enhance the dust activity. A decline in the strong wind frequency during 1999−2012 results in a decreasing trend in the modeled dust emission, at a rate of -7.81±2.73 Mt yr-1, as well as a decreasing trend in the ground observed dust frequency index, at a rate of -0.14±0.04%. We estimate that 58.4% of dust emission is caused by human activity during the 1999−2012 period. Our estimates suggest human plays an important role in the region’s dust budget through agriculture and water resource usage.
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Thomas, Timothy William. "Assessment of the mixing state and cloud nucleating efficiency of Asian aerosols using aircraft-based measurements of hygroscopicity." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/3980.
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Global warming theories continue to overestimate their predictions of increased mean global temperatures (Hudson 1991). This would imply that some other influence is counteracting the global warming influences; i.e. a cooling effect. Cloud albedo characteristics are currently being researched to determine the impact clouds have on the net cooling of the atmosphere in relation to the global warming theory. These characteristics are influenced by the type, size, composition, and abundance of aerosol particles that act as cloud condensation nuclei. This study employs Tandem Differential Mobility Analyzer (TDMA) data collected in the vicinity of Japan during the Asian Aerosol Characterization Experiment (ACE-Asia) to investigate the influence of aerosol concentration and composition on the light scattering properties of clouds. Measurements of particle size (Dp), particle growth factor (GF), and relative humidity (RH) yield critical supersaturations (Sc) with the assumption that the soluble part of the particle is composed primarily of one substance. This indirect composition analysis allows us to determine whether the aerosol was internally mixed (particles have uniform composition and yield a single-peak distribution or similar growth factors) or externally mixed (different particles have different compositions yielding multiple peaks in the distribution). Through the use of calculated supersaturations, we can gain insight into cloud droplet activation properties of the samples for various aerosol types, which ultimately allows us to look at the influence of these particles on albedo characteristics of clouds formed by these particles.
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Ruiz, Mori Hernán Jorge. "Eficacia de la terapia de nebulización vs. inhalación con fenoterol en la crisis asmática moderada infantil, en el Hospital de Emergencias Pediátricas, año 2004." Master's thesis, Universidad Nacional Mayor de San Marcos, 2007. https://hdl.handle.net/20.500.12672/1067.
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La prevalencia de la crisis asmática se ha incrementado dramáticamente en la última década, constituyendo un problema de salud pública. El tratamiento de elección es el uso de broncodilatadores por vía inhalatoria, existiendo dos modalidades para administrar el broncodilatador: la Nebulización y la Inhalación. Hasta la actualidad hay controversias sobre la modalidad más eficaz, aquella que tiene una mejor respuesta clínica en el niño; siendo la nebulización la más utilizada.
El objetivo del trabajo de investigación es determinar y comparar la eficacia de estas dos modalidades terapeúticas, en los niños escolares con crisis asmática moderada, a través del puntaje clínico de Bierman-Pierson-Tal modificado y la saturación de oxígeno, empleando como broncodilatador el fenoterol. Es un estudio analítico, prospectivo, transversal y quasiexperimental, realizado en el Hospital de Emergencias pediátricas. De una población total de 2,553 niños escolares con crisis asmática en el año 2003, se tomaron para el estudio por muestreo probabilístico 160 niños de edad escolar que llegaron al servicio de emergencia desde abril hasta octubre del año 2004, quiénes fueron distribuídos en dos grupos: “A” los 80 niños nebulizados y “B” los 80 niños inhalados.
La edad promedio fue 8.75 años en el grupo “A” y 9.1 años en el grupo “B”, el puntaje clínico de severidad tuvo una mediana y moda de 6 para ambos grupos, la saturación de oxígeno tuvo una mediana de 94 para ambos grupos, una moda de 95 para el grupo “A” y 94 para el grupo “B”, en el número de nebulizaciones empleadas la mediana y moda fue de 3, en el número de inhalaciones empleadas la mediana y moda fue 6, el tiempo promedio de permanencia en emergencia fue 98 minutos para el grupo “A”, 67 minutos para el grupo “B”, y la moda fue 90 minutos para el grupo “A” y 60 minutos para el grupo “B”. Teniendo como resultado final el éxito en el 100% de niños en ambos grupos.
Concluyendo que ambas modalidades de terapia para administrar el broncodilatador Fenoterol, la nebulización y la inhalación son igualmente eficaces en los niños escolares con crisis asmática moderada.
Palabras claves: Asma, niños.Tesis
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Vancuren, Richard A. "Asian aerosols in North America : frequency and intensity of transpacific transport, chemical composition, and mass concentrations /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Kuhlmann, Julian, and Johannes Quaas. "How can aerosols affect the Asian summer monsoon?: assessment during three consecutive pre-monsoon seasons from CALIPSOsatellite data." Copernicus Publications, 2010. https://ul.qucosa.de/id/qucosa%3A13831.
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The impact of aerosols above and around the Tibetan Plateau on the Asian Summer Monsoon during premonsoon seasons March-April-May 2007, 2008, and 2009 is investigated by means of remote sensing and radiative transfer modelling. Four source regions are found to be responsible for the high aerosol loading around the Tibetan Plateau: the Taklamakan Desert, the Ganges Plains, the Indus Plains, and the Arabian Sea. CALIPSO lidar satellite data, providing vertically resolved images of aerosols, shows aerosol concentrations to be highest in the lower 5 km of
the atmosphere with only little amounts reaching the Tibetan Plateau altitude. Using a radiative transfer model we find that aerosol plumes reduce shortwave radiation throughout the Monsoon region in the seasonal average by between 20 and 30 W/m2. Peak shortwave heating in the lower troposphere reaches 0.2 K/day. In higher layers this shortwave heating is partly balanced by longwave cooling. Although
high-albedo surfaces, such as deserts or the Tibetan Plateau,
increase the shortwave heating by around 10%, the overall effect is strongest close to the aerosol sources. A strong elevated heating which could influence large-scale monsoonal circulations as suggested by previous studies is not found.
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Cachay, Díaz José Ramiro. "Evaluación clínico-flujométrica en exacerbaciones agudas de asma bronquial, tratados con Fenoterol, en un Servicio de Emergencia, en adultos." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2015. https://hdl.handle.net/20.500.12672/13500.
Full textAbstract:
PROBLEMA: “¿Cuáles son los cambios clínico-flujométricos observados en pacientes con exacerbaciones agudas de asma bronquial leve, moderado y severo, con nebulización convencional en el servicio de emergencia del Hospital Nacional Arzobispo Loayza?”
OBJETIVO: Determinar los cambios en la función pulmonar medida con PEF y cambios clínicos en exacerbaciones agudas leves, moderadas o severas del asma bronquial en adultos sometidos a nebulización convencional.
METODOLOGÍA: Es un estudio descriptivo, observacional, prospectivo, realizado en emergencia del Hospital Nacional Arzobispo Loayza; se evaluó 136 pacientes mayores de 18 años con exacerbación aguda leve, moderada y severa de asma bronquial, nebulizados con fenoterol, con un IC de 95%, z de 1.96, potencia de 80% (para una muestra de 131 pacientes); se excluyeron enfermedades respiratorias y cardiacas crónicas y asma casi fatal, etc. Se midió la variación del PEF, la mejoría clínica, estancia en la sala de emergencia, requerimiento de hospitalización y recaídas. Se estimó las frecuencias absolutas y relativas de cada variable y en algunos casos se sometió a pruebas de significación estadística para determinar las diferencias. La información se presenta en cuadros y gráficos.
RESULTADOS: Se reclutó 136 pacientes asmáticos, 108 mujeres, y 28 varones, 56 casos leves (41.2%), 60 casos moderados (44.1%) y 20 severos (14.7%); la edad promedio de los casos fue de 36.3 años, siendo de 50.6 años en el grupo de mayor severidad. Todos usaban beta agonistas como broncodilatador, y más de la mitad (55.9%) usaba corticoides en cualquiera de sus formas, el 35% usaba corticoides vía oral en sus crisis.
La mayoría (64.7%) esperaba más de 1 día de inicio de la crisis para atenderse, todos los grupos tuvieron variación de la frecuencia cardiaca tras la nebulización siendo el de mayor taquicardia en el grupo de severo. No se registraron casos de asma casi fatal o asma fatal.
El tiempo de espera y de estancia para ser atendido, fue variable, siendo el tiempo de estancia más prolongado en los casos severos, y en los afiliados al SIS.
Se observó una variación de 84ml/s (17% del predicho) en el PEF en los casos leves, de 109ml/s (23% del predicho) en los moderados, y de 158ml/s (34% del predicho) en los severos. Fué necesarios al menos 2 nebulizaciones en los casos leves, 3 nebulizaciones en los moderados y 4 nebulizaciones en los severos para obtener mejoría clínica y flujométrica. Hubo 5% de recaídas y de 40% de hospitalizaciones, todos pertenecientes al grupo de severo.
CONCLUSIONES: Se encontró una variación en el PEF de 84ml/s (17% del predicho) en los casos de asma leve, de 109ml/s (27% del predicho) en los moderados, y de 158ml/s (34% del predicho) en los casos severos. Siendo necesario, para mejorar, 2 nebulizaciones en los casos de exacerbaciones de asma leve, 3 nebulizaciones en los casos de asma moderada, y de 4 nebulizaciones en los casos de asma severa.Trabajo académico
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Luján, Acevedo Ronald. "Salbutamol inhalado versus nebulizado en asma bronquial leve-moderada en niños de 2 a 14 años, que ingresan a emergencia del Hospital Regional de Chimbote. Junio-diciembre 2007." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2008. https://hdl.handle.net/20.500.12672/12602.
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El documento digital no refiere asesorDiseña un ensayo clínico aleatorizado, abierto, para comparar la eficacia del salbutamol administrado por inhalación en dosis fijas mediante una cámara espaciadora, con la del mismo medicamento suministrado por nebulización, en niños asmáticos entre uno y seis años de edad que padecieran una exacerbación aguda de su enfermedad. Se seleccionó una muestra de 70 pacientes que llegaron al servicio de urgencias del Hospital Infantil Arzobispo Caicedo de la ciudad de Medellín, Colombia, en el transcurso de seis meses. Se trataron 38 casos en el grupo nebulizado y 32 en el de inhalados. Los grupos fueron comparables en lo referente a su edad, la gravedad de la exacerbación, los signos clínicos iniciales y la duración de los mismos al ingreso, en el cual no hubo diferencias significativas comparadas antes y después del tratamiento. Se hizo un análisis de los promedios de las mismas variables pre y postratamiento en cada uno de los grupos con el fin de verificar si existía mayor mejoría en uno que en el otro; en el cual se obtuvo una mejoría similar y significativa de la saturación de oxígeno, pero que la frecuencia respiratoria no varió significativamente.
Trabajo académico
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Iparraguirre, Reyes Blanca Luz. "Efectividad de una intervención educativa de enfermería sobre manejo de inhaladores en las prácticas de padres de niños hospitalizados del Hospital de Vitarte, 2017." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2018. https://hdl.handle.net/20.500.12672/8027.
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Publicación a texto completo no autorizada por el autorDemuestra la efectividad de una intervención educativa de enfermería sobre manejo de inhaladores en las prácticas de padres de niños hospitalizados respecto a la dimensión uso del inhalador y aero cámara, y mantenimiento del inhalador y aero cámara antes y después de la intervención educativa. El estudio fue de nivel aplicativo, tipo cuantitativo, método pre experimental, la población estuvo conformada por 30 padres, se utilizó como técnica la observación y como instrumento una lista de chequeo, el cual fue aplicado antes y después de la intervención educativa, previa solicitud del consentimiento informado antes de realizar la intervención educativa. En cuanto a las prácticas de los padres de niños hospitalizados sobre el manejo del inhalador de un total de 30 (100%) padres, antes de la aplicación de la intervención educativa se evidencia que 18 (60%) tienen prácticas inadecuadas y solo 12 (40%) tienen prácticas adecuadas: después de la aplicación de la intervención educativa el 30(100%) tienen prácticas adecuadas. Concluye en la aceptación de la hipótesis de estudio el cual fue demostrado a través de la prueba T de Student que la intervención educativa señalando que es efectivo en el incremento de prácticas de los padres sobre el manejo del inhalador.
Trabajo académico
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Wang, Cheng Chuan, and 王證權. "Asia aerosol characterization experiment--Chemical characterization of atmospheric aerosols in North Beach, Taiwan in spring." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/95356785738508383513.
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碩士國立中央大學
環境工程研究所
89
China dust storms play a significant role in the radiation budget, climate change, visibility degradation, health effects, and the equilibrium of ecosystems in East Asia (Chung et al., 1996). In collaboration with the major countries of Pacific Rim on the monitoring of China outflow, this study collects PM2.5 and PM10 at Shi-Men in Taipei County from March to May in 2001. Aerosol mass concentration, water-soluble ions, carbonaceous content, and elemental content were resolved from the collected filters. The results demonstrate a contrast of aerosol chemical properties between dust storm events and normal days in the Taiwan northern coast. During dust storm events, the average mass from PM2.5, PM10, and PM10-2.5 was 43.7, 124.4, and 80.8 μg/m3, respectively. In contrast, that of PM2.5, PM10, and PM10-2.5 was 26.0, 50.6, and 24.5 μg/m3, respectively. It shows that PM10-2.5 dominated PM10 fraction with more than triple fold in the dust events as compared to normal days. In addition, the concentrated species in the dust storm events were Ca2+, Ca, Fe, and Si. For the ratio of organic carbon to elemental carbon (OC/EC), the values in the dust storm events ranged between 1.5~2.29 that were smaller than 3.26~3.30 in the normal days. More, the fraction of SO42- in PM10 and PM2.5 during the events was found smaller than that of normal days. This result implies the hindrance of dust storms on the formation of secondary aerosols. In validating the analytical accuracy on aerosol composition, a method of reconstructed mass was adopted to convert aerosol species into aerosol compounds. The method increased the resolved mass fraction PM2.5 and PM10 to a value of 79.3 and 94%, respectively. From the calculation of chlorine loss, we found 61.8% of PM2.5 is secondary sulfate, whereas 38.5 and 27.6% of PM10 is secondary sulfate and sea-salt aerosol, respectively. Meanwhile, the absolute principal component analysis shows the most significant source of PM2.5 contributed 65.5% of mass concentration, which is a source mixed with anthropogenic activity, vehicle emission, and secondary reactions. In contrast, sea-salt spraying, resuspended dusts, agricultural burning, and part of the secondary reactions contributed 61.7% of PM10. The consistency between chlorine loss and absolute principal component methods confirms the results of aerosol source apportionment in this study.
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Duvall, Rachelle Monique. "Chemical characterization and source apportionment model study of atmospheric aerosols in Asia." 2005. http://catalog.hathitrust.org/api/volumes/oclc/65649395.html.
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Tomlinson, Jason. "The Evolution of the Physicochemical Properties of Aerosols in the Atmosphere." 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8904.
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A Differential Mobility Analyzer/Tandem Differential Mobility Analyzer (DMA/TDMA) system was used to measure simultaneously the size distribution and hygroscopicity of the ambient aerosol population. The system was operated aboard the National Center for Atmospheric Research/National Science Foundation (NCAR/NSF) C-130 during the 2006 Megacity Initiative: Local and Global Research Observations (MILAGRO) field campaign followed by the 2006 Intercontinental Chemical Transport Experiment – Phase B (INTEX-B) field campaign.
The research flights for the MILAGRO campaign were conducted within the Mexico City basin and the region to the northeast within the pollution plume. The aerosol within the basin is dominated by organics with an average measured kappa value of 0.21 /- 0.18, 0.13 /- 0.09, 0.09 /- 0.06, 0.14 /- 0.07, and 0.17 /- 0.04 for dry particle diameters of 0.025, 0.050, 0.100, 0.200, and 0.300 mu m, respectively. As the aerosols are transported away from the Mexico City Basin, secondary organic aerosol formation through oxidation and condensation of sulfate on the aerosols surface rapidly increases the solubility of the aerosol. The most pronounced change occurs for a 0.100 mu m diameter aerosol where, after 6 hours of transport, the average kappa value increased by a factor of 3 to a kappaof 0.29 /- 0.13. The rapid increase in solubility increases the fraction of the aerosol size distribution that could be activated within a cloud.
The research flights for the INTEX-B field campaign investigated the evolution of the physicochemical properties of the Asian aerosol plume after 3 to 7 days of transport. The Asian aerosol within the free troposphere exhibited a bimodal growth distribution roughly 50 percent of the time. The more soluble mode of the growth distribution contributed between 67-80 percent of the overall growth distribution and had an average kappabetween 0.40 and 0.53 for dry particle diameters of 0.025, 0.050, 0.100, and 0.300 mu m. The secondary mode was insoluble with an average kappabetween 0.01 and 0.05 for all dry particle diameters. Cloud condensation nuclei closure was attained at a supersaturation of 0.2 percent for all particles within the free troposphere by either assuming a pure ammonium bisulfate composition or a binary composition of ammonium bisulfate and an insoluble organic.
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Hung, Chung-Min, and 洪崇閔. "Characteristics of Chemical Fingerprint and Long-range Transport of Marine Aerosols in East Asia." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/4n73cp.
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碩士國立中山大學
環境工程研究所
106
Over the past decades, the industries and commerce rose up fastly in East Asian countries. The increase of fuel consumption and pollution emission lead to poor air quality in the region. Taiwan Strait and South China Sea are surrounded by Taiwan, China, Philippine, and Indochina Peninsula. The northeastern monsoons in winter and spring bring air pollutants (such as haze) and Asian dust to downwind region coupled with the growth of slash-and-burn in the spring in the Southeast Asia, which cause the deteroiation of ambient air across the Taiwan Strait and South China Sea via long-range transport. Accordingly, this study aims to explore the spatiotemporal variation, chemical characteristics, and source apportionment of PM2.5 in East Asia. PM2.5 samples were collected simultaneously at the Penghu Islands, the Dongsha Islands, the Nansha Islands from August 2017 to April 2018. After sampling, PM2.5 filters were carried back to the laboratory for further conditioning, weighing, and chemical analysis. Water-soluble ions, metallic elements, carbonaceous contents, anhydrosugars, and organic acids were then analyzed to charactaize the chemical fingerprint of PM2.5 in East Asia. Furthermore, backward trajectory simulation and chemical mass balance (CMB) receptor modelling were applied to identify the potential sources of PM2.5 and their contribution in each season.Field sampling results indicated that high concentrations of PM2.5 were observed mainly in winter and spring. During the northeastern monsoons periods, anthropogenic pollutants from northern region were brought to the target area, resulting in significant increase of PM2.5 concentration. From the perspective of diurnal variation, the concentration of daytime PM2.5 was generally higher than those at nighttime at all sites in all seasons. Chemical analytical results showed that secondary inorganic aerosols (NO3-, SO42-, and NH4+) dominated water-soluble ions, accounting for 42.4-79.9% of water-soluble ions particularly in winter and spring. Daytime PM2.5 concentration was commonly higher than that at nighttime. Crustal elements (Ca, K, Mg, Fe, Al) dominated the metallic elements in PM2.5. The concentration of hazardous metals (V, Cr, Mn, Ni, Zn, and Cd) came mainly from anthropogenic sources since fall. Moreover, organic carbon (OC) was the dominant carbonaceous species during the sampling periods, and OC/EC ratio increased during the northeastern monsoon periods. The concentrations of levoglucosan at the sampling sites were ordered as PH>DS>NS. The highest levoglucosan concentrations of 23.54 ng/m3 were observed at the Penghu Islands. Organic acids of PM2.5 at the Penghu Islands were commonly higher than those at the Dongsha Islands and the Nansha Islands. Oxalic acid was the abundant organic acids in PM2.5. The concentrations of oxalic acid at all sampling sites ranged from 5.1 to 246.2 ng/m3. The mass ratios of malonic and succinic acids (M/S ratio) in PM2.5 ranged from 0.95 to 1.41, showing that PM2.5 was mainly attributed from secondary organic aerosols (SOAs). Daytime organic acid concentrations were always higher than those at nighttime. Results obtained from CMB receptor modeling showed that the major sources of PM2.5 at the three sampling sites were sea salts, fugitive dusts, mobile sources, secondary sulfate, and secondary nitrate. Since fall, the contribution of anthropogenic sources (incinerators, petrochemical plants, industrial boilers, secondary sulfate, secondary nnitrate) and biomass burning increased gradually. Overall, the contribution of long-range transport at the Penghu Islands, the Dongsha Islands, and the Nansha Islands accounted for 14~56%, 29~72%, and 18~60%, respectively. The contribution of anthropogenic sources (mobile sources, industrial process, industrial boilers, incinerators, and steel plants) and biomass burning in the daytime was generally higher than those at nighttime. The contribution of biomass burning to PM2.5 in winter and spring were generally higher than those in other seasons.
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Cai, Zong-Ting, and 蔡宗廷. "Discrimination of Aerosol Types with MODIS Data in Asia." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/27977144279011419000.
Full textAbstract:
碩士國立中央大學
太空科學研究所
99
The main aim of study is to identify aerosol types based on the spectral radiance observed by Moderate Resolution Imaging Spectroradiometer (MODIS). Three datasets are collected for the discrimination of aerosol types, including volcanic ash, smoke plumes and mineral dust, during the periods of Icelandic volcano eruption, Southeast Asian biomass burning and Asian dust storm events. According to the analysis of thermal radiation (brightness temperature), the BTDI (Brightness Temperature Difference Index) in split window of smoke plumes (3.408±0.141) are larger than both volcanic ashes (-2.395±0.646) and dust particles (-1.729±1.001), suggesting that the BTDI can be an optimal indicator for the discrimination of smoke from volcanic ash and dust particles. For the radiometric characteristics in visible and near infrared spectral band, smoke plumes and clean land surface have a distinct difference in reflectivity in MODIS band 2 (850nm), band 3 (469nm), dand 8 (413nm), band 9 (443nm) and band 17 (905nm). Therefor, these bands can be an optimal indicator for the discrimination between smoke plumes and land surface. Dust particles and volcanic ashes have a distinct difference in reflectivity between band 17 ( 905nm ) and band18 ( 936nm ) of MODIS and the difference between these two bands can be an optimal indicator for the discrimination between volcanic ash and dust particles. On the other hand, the BTDI observed by satellite is composed of contribution by aerosol (dust and ash) and water vapor in the environment if a pixel cell is not full filled with aerosol particles. Therefor, we can derive the fractions of BTDI contributed by aerosols and water vapor. As a result, an ensemble method for diseriminating the aerosol type has been integtated in this study.
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Chen, I.-Jen, and 陳佁甄. "Aerosol Impact on East Asian Summer Monsoon." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/00171086521353606281.
Full textAbstract:
碩士國立臺灣大學
大氣科學研究所
102
Asia has the strongest monsoon system in the world and has the most population continent. In addition to Indian monsoon, East Asia is another area with strong monsoon system, high population and high aerosol pollution. The relevant studies show that aerosol causes decrease in surface temperature, reduction of precipitation and the weakness of monsoon system. However, less research was studied further into the dynamical feedback. This study focuses on the how aerosol will change the East Asian summer monsoon. We apply the NCAR/CESM global model with slab ocean model to get a better ocean feedback, and simulate the year 1850 and 2000 emission scenarios in order to estimate the influence of anthropogenic aerosol forcing and to approach the problem from different perspectives, including dynamical feedback. The result shows that in total aerosol forcing, the direct radiative forcing is main-ly on the high aerosol distribution area. Aerosol indirect effect follow the cloud movement of the synoptic system and influence the whole Asia. The mean regional surface temperature and precipitation decreased by -1.07°C and -0.46 mm/day, respec-tively, over East Asia , but the responses vary significantly from region to region. The dynamical feedback of aerosol forcing, which affect the sea surface temperature and the strength of Pacific high ridge by indirect effect, shows that the wind-evaporation-SST feedback causes the inconsistency distribution between surface temperature and radiation. The main aerosol emission region shows the reduction of temperature, but cause the updraft at the mei-yu front and has more precipitation in the result. This may due to trigger the Pacific-Japan pattern (P-J pattern) feedback, while we see the similar structure in the result. Overall, aerosol particles cause large regional subsidence anomaly, resulting in weakened summer monsoon. When considering only absorbing (black carbon) or non-absorbing (sulfate) aero-sols, the changes in surface temperature are +0.18°C and -0.53°C, respectively; where-as the changes in precipitation are -0.35 mm/day and -0.34 mm/day, respectively. Non-absorbing aerosol can scatter the solar radiation, causing the temperature decrease and stabilize atmosphere. Absorbing aerosol shows heating atmosphere can com-pensate the radiation reduction at surface, while the combined effect shows stabilizing atmosphere. The dynamical feedback of WES feedback and P-J pattern are show in the absorbing and non-absorbing aerosol result, only with a weaker phenomenon.
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Li, Xiaoqiong. "Asian summer monsoon response to greenhouse gases and anthropogenic aerosols." Thesis, 2018. https://doi.org/10.7916/D8M05P9T.
Full textAbstract:
The Asian monsoon-affected area is one of the most vulnerable regions in the world facing hydroclimate changes. Anthropogenic climate change, particularly the emissions of greenhouse gases (GHGs) and aerosols, exerts significant impacts on monsoon rainfall and circulation. Understanding the effects of external forcing on monsoon rainfall is essential for improving the predictability, constraining the uncertainty, and assessing the climate risks. In this dissertation, I use a combination of observations, outputs from multiple Coupled Model Intercomparison Project - Phase 5 (CMIP5) models, and idealized atmospheric general circulation model (AGCM) experiments to examine the Asian summer monsoon variability and change. The main focus is understanding the responses to GHGs and anthropogenic aerosols and their differences for both the historical period and future projections.
The Asian monsoon is an interactive system influenced by multiple natural and anthropogenic factors. GHGs and aerosols induce significantly different changes in monsoon rainfall through both thermodynamical and dynamical processes. These changes can be further separated into the fast adjustments related to radiation and cloud processes and the slow response due to changes in sea surface temperature (SST). This thesis provides a detailed analysis of the multiple physical processes entangled in the total response, advancing our mechanistic understanding of the effects of external forcing on the Asian monsoon system and the associated uncertainties.
In Chapter 2, I first analyze the monsoon-ENSO (El Nino - Southern Oscillation) relationship in observations and CMIP5 models to determine the role of natural variability. Separating the natural and forced components shows that natural variability plays a dominant role in the 20th century, however enhanced monsoon rainfall associated with global warming may contribute to a weakened ENSO-monsoon relation in the 21st century. In Chapter 3, I examine the physical mechanisms causing the changes of the Asian summer monsoon during the 20th and 21st century using observations and CMIP5 models, attributing the rainfall changes to the relative roles of thermodynamic and dynamic processes. CMIP5 models show a distinct drying of the Asian summer monsoon rainfall during the historical period but strong wetting for future projections, which can be explained by the strong aerosol-induced dynamical weakening during the 20th century and the thermodynamic enhancement due to GHGs in the 21st century.
In Chapters 4 and 5, I further use multiple AGCMs to separate the total monsoon response into a fast adjustment component independent of the sea surface temperature (SST) responses, and a slow response component associated with SST feedbacks. For GHGs (Chapter 4), the fast and slow monsoon circulation changes largely oppose each other, leading to an overall weak response and large inter-model spread. For aerosols (Chapter 5), the strongly weakened monsoon circulation over land due to aerosols is largely driven by the fast adjustments related to aerosol-radiation and aerosol-cloud interactions. Finally in Chapter 6, I design idealized AGCM experiments with prescribed SSTs using the Community Atmosphere Model (CAM5) and the Geophysical Fluid Dynamic Laboratory Model (GFDL-AM3) to investigate the relative roles of uniform SST warming/cooling as well as global and regional SST patterns in shaping the differing monsoon responses. While GHGs-induced SST changes affect the monsoon largely via the uniform warming effect, for aerosols the SST spatial pattern plays the dominant role through changes in atmospheric circulation.
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Gerelmaa and 戴吉莉. "SATELLITE REMOTE SENSING OF AEROSOL CHARACTERISTICS OEVR ASIAN REGION." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/82611812047288154053.
Full textAbstract:
博士國立中央大學
大氣物理研究所
103
This thesis focusses on investigating the aerosol characteristics over Asian region using satellite remote sensing. Seven years of aerosol optical thickness (AOT) product from MODerate Imaging Spectroradiometer (MODIS) onboard Aqua and Terra satellites during the years 2002-2008 are analyzed for the study. Ground observations of aerosol robotic network (AERONET) at different stations within the study area are used to validate the MODIS AOT. Angstrom exponent (AE), and fine mode fraction (FMF) from MODIS and AERONET are used to discuss the size, type and possible sources of the particles. National Center for Environmental Prediction, National Center for Atmospheric Research (NCEP-NCAR) reanalysis data and Global Precipitation Climatology Center (GPCC) data are used to obtain the meteorological parameters over the study area. A detailed correlation analysis of AOT and AE has been carried out to validate the MODIS data using corresponding AERONET measurements over 16 selected stations. Behavior of the MODIS-AERONET correlation in different seasons is investigated to understand the response of the two measurements for varying aerosol types. The results indicate very high (> 0.9) correlation of AOT between MODIS and AERONET, while the corresponding AE correlation is poor, but seems to improve if only those data points with corresponding AOT > 0.5 are considered. Further analysis is carried out to examine permanent aerosol source regions over Asia. The methodology involves taking average AOT map during the years over the region in different seasons, in which the permanent source regions will appear pronounced whereas the locations influenced by transport or any emissions that last shorter time period will be smoothened. The results reveal four main such source regions: (1) the region at North and North-West of China and South of Mongolia, (2) Eastern part of China, (3) North-East of Indian continent, and (4) Parts of Thailand, Vietnam and Indonesia. The average AOT trends over the source regions in the years are examined in different seasons together with the corresponding variations of meteorological parameters and the results suggest an increase in the emissions. In order to understand how the permanent source regions influence the surrounding locations, the aerosol properties selected East Asian stations of Beijing, Gosan, Osaka, Taipei, Mukdahan, and Bac-Gaing are further investigated in detail. The daily, monthly, seasonal, and inter-annual variations of the AOT are described along with meteorological parameters from NCEP-NCAR reanalysis and GPCC data. AE and FMF from MODIS and AERONET are used to discuss the size, type of particles. Seasonal wind pattern are used to understand the transport of particles from the source regions to the chosen stations. The results suggest that maximum aerosol loading occur over Beijing with daily mean AOT reaching above 2.0. Gosan and Taipei are among the stations having smallest AOT in most of the seasons with values below 0.5. The detail analysis of the AOT characteristics over Mukdahan, and Bac-Giang are reported for the first time. Dust influence appears to be significant over Beijing, Osaka, as well as Gosan, and to a lesser extent over Bac-Giang in the spring, while pollution, bio-mass burning, etc. contribute in the summer and spring over all the stations. The increasing AOT trend over the permanent source region (1) mentioned above seems to result in the observed increase of AOT trend over Osaka and Gosan, and also over Beijing.
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Wang, Sheng-Hsiang, and 王聖翔. "Estimate of radiative forcing and regional feedback of Asian biomass burning aerosols." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/33624398683032520381.
Full textAbstract:
博士國立中央大學
大氣物理研究所
95
The purpose of this study is to estimate the regional radiative impact of Asian biomass burning aerosols during the experimental period of Transport and Chemical Evolution over the Pacific (TRACE-P) in March, 2001. Integration of the Fifth-Generation NCAR / Penn State Mesoscale Model (MM5), USA NOAA Hybrid Single-Particle Lagrangian Integrated Transport model (HYSPLIT) and a solar radiative transfer model (CLIRAD-SW) allow us to simulate the spatial and temporal distributions of black carbon (BC) and organic carbon (OC) aerosols from biomass burning. It also allows us to estimate further their aerosol optical properties and radiative forcing. Emissions of BC and OC aerosols from biomass burning sources were based on a higher spatial and temportal resolution of emissions during TRACE-P. The results show that the monthly mean surface concentration of OC and BC is 1.2 μg m-3 in the South Asian region (70o–110oE, 5o–30oN). Western Myanmar has the maximum value, with the concentration reaching 14.1 μg m-3. There is a persistent aerosol layer with a thickness of 3 km over most of the South Asian region, and the plumes of biomass burning aerosols extend far to the Indian Ocean and the western Pacific Ocean. The aerosol optical depth (AOD) of the biomass burning carbon aerosols reaches a maximum value of 0.14 over western Myanmar. Compared to the OC aerosol, the BC aerosol makes a remarkable contribution to the AOD, especially in the source region. The monthly mean clear-sky direct shortwave radiative forcing ranges from -1.81 (sea) to 1.08 (land) W m-2 at the top of the atmosphere and from -0.04 to -9.48 W m-2 at surface. The monthly mean all-sky direct shortwave radiative forcing ranges from -1.65 (sea) to 1.42 (land) W m-2 at the top of the atmosphere and from -0.03 to -9.06 W m-2 at surface. The existence of cloud contributes a positive increase of radiative forcing. Owing to the spatial distributions of the AOD ratio (OC/BC) and the surface albedo, there is a sea-land distribution of radiative forcing at the top of the atmosphere. Biomass burning aerosols result in less solar irradiance reaching the Earth’s surface, but greater heating in the lower atmosphere, particularly for the BC aerosols, which have stronger atmosphere radiative forcing and the atmospheric heating rate. The BC aerosols cause surface radiative forcing 5-7 times more than that due to the OC aerosols. The biomass burning aerosols result in an increase of the atmospheric heating rate up to 6ºC month-1 in lower atmosphere of the source region. There is a strong horizontal gradient of heating rate near the source regions, which may modify local circulations. We test the regional meteorological feedback due to biomass burning aerosol surface radiative forcing, and find that the surface temperature decreases 2ºC month-1 in the same region. Meanwhile, monthly sea level pressure and cloud mounts in the domain vary in -2.5－0.5 hPa and 20 %, respectively. The accumulate precipitation varies more than ± 500 mm in the southern Asia in March, 2001. The results imply the biomass burning aerosols have significant influences on the regional climate change. However, a more complete feedback mechanism included in the model is needed for a rationable investigation on how the radiative forcing affects the regional meteorological variations.
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Chih-chieh, Tsai, and 蔡智傑. "The temporal and spacial variation of aerosol index and size distribution in Northeastern Asia." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/88639073399057421950.
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碩士國立臺灣海洋大學
海洋環境資訊學系
95
The high long-term monthly average of TOMS (Total Ozone Mapping Spectrometer) AI (Aerosol Index) in Northeast Asia in spring is influenced by the dust storm or the biomass burning transported from Southeast. In summer, the high AI value on the ocean is mainly caused by inputs of sea salt on the sea surface or industrial pollution. Angstrom value increases with the size of particle decreasing. This paper used the GACP Angstrom value to observe aerosol size distribution. From the long-term 3oX3o regional monthly mean, the distribution of Angstrom seems to have same temporal and special variation with TOMS AI. For example: Dust storm can raise the finer size dust aerosol particle and transport to far away from the source that cause high Angstrom value appear the southern、southeast and eastern of the high AI value in spring and winter when dust storm mainly happen. The high Angstrom and high AI on sea surface in spring are caused by fine size particle which generated by biomass burning. The monthly mean of Angstrom decrease progressively from the land to the sea during the dust storm season. It is corresponding to the dust storm particle precipitating with dust storm transmitting. Keywords: Aerosol index，TOMS，Angstrom
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"Optical Properties of Free Tropospheric Aerosol Particles Related to the Relative Humidity as Derived from Raman Lidar Observations at Nagoya: Contributions of Aerosols from the Asian Continent and the Pacific Ocean." Thesis, 2000. http://hdl.handle.net/2237/6418.
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Sakai, Tetsu, and 哲. 酒井. "Optical Properties of Free Tropospheric Aerosol Particles Related to the Relative Humidity as Derived from Raman Lidar Observations at Nagoya: Contributions of Aerosols from the Asian Continent and the Pacific Ocean." Thesis, 2000. http://hdl.handle.net/2237/6418.
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Huang, Hsi-Erh, and 黃希爾. "The influence of biomass burning in East-Asia to the characteristic of alpine aerosol in Taiwan." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/74481192027705009451.
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碩士國立中央大學
環境工程研究所
92
Every spring from March to April, it is the time period for active biomass burning in East Asia. The aerosols produced from biomass burning were lifted 2 to 5 Km above the ground by the rise of a frontal system and a strong convective air mass. They were then transported to the other areas by the air mass in the high altitude. This study chose Lu-Lin Mountain, as the study site for aerosol collection, which situated in the middle Taiwan 2,862 m above sea level. The goal of this study is to observe the aerosol characteristics from biomass burning in East Asia via long range transport in lower free troposphere. The observations included two biomass burning events in April 2003 and March 2004 and a background observation in December 2003. This study used manual sampler and continuous measuring instrument to obtain the information of aerosol from the two biomass burning events and bacdground. Besides, in order to infer the characteristic of the fresh aerosol near biomass source, we burned wood and hay and used manual sampler to correct fresh aerosol. Comparing the aerosol of fresh-burning biomass and Lu-Lin Mountain, we can tell the differences of long-range transport. The results showed that PM2.5 and PM10 concentrations are 2 and 4 μgm-3 for background observations, respectively. The peak diameter is in the range between 0.1-0.3 μm and major chemical species are sulfate, ammonium ions, nitrate, and carbonaceous materials. For biomass burning events, aerosol mass was increased and specises like sulfate, ammonium ions, nitrate, and carbonaceous materials were all enhanced. In addition, potassium ion was found significantly increased in aerosol fine fraction. Moreover levoglucosan in aerosol was detected high during biomass burning period with an average of 48 ngm-3. In TOR analysis, OC1 is in majority in background observation and OC3 is predominant in biomass burning events. By using Hysplit backward air trajectory model, we find that aerosol are high in potassium ion, carbonaceous materials, and levoglucosan as the air mass passed biomass-burning sources. Besides, using Marine Enrichment Factor(MEF) and Chlorine Loss Method(CLM), we find that the water-solube ions in fine fraction are contributed from secondary sulfate, secondary nitrate and biomass burning. In contrast, the coarse particles included soil materials and seat-salts. Finally, aerosols from long range transport contain high fraction of sulfate, nitrate, and ammonium ions as compared to high carbonaceous material, potassium, and chloride ions.
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Duvall, Rachelle Monique. "Size-resolved chemical composition and water-soluble fraction of atmospheric aerosols collected from the Asian continent." 2002. http://catalog.hathitrust.org/api/volumes/oclc/51555131.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 2002.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 104-106).
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Chun-YehLin and 林群燁. "The Impact of the Physicochemical Characteristics of Atmospheric Aerosol in Tainan from Asian Dust Storm." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/56765244705807707889.
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碩士國立成功大學
環境工程學系碩博士班
98
In recent years, Asian dust storms have occurred more and more frequently. During the dust storm period, Asian dusts not only induce poor air quality, but also reduce atmospheric visibility and influence human health. In order to investigate the physicochemical characteristics of Asian dusts, this study collects the PM10 and PM2.5 in the Tainan city during the years of 2003~2009. In addition, this study analyzed the backward trajectory by using HYSPLIT MODEL to differentiate the source and passing regions of each dust storm event. During Asian dust storm periods, the concentration of atmospheric particulate matter (PM10) in the Tainan city increased significantly, roughly 2 to 6 times of greater PM10 concentrations. Among them, coarse particles rose particularly from 20~50 μg/m3 to 80~125 μg/m3. This study further analyzed the chemical compositions of Asian dusts; for coarse particles, the order of water-soluble ionic species was SO42-＞NO3-＞NH4+＞Cl-＞Ca2+＞Na+＞K+＞Mg2+＞NO2-. For fine particles, the order of water-soluble ionic species was SO42- ＞ NO3- ＞ NH4+ ＞ Cl- ＞ K+ ＞ Na+ ＞ Ca2+ ＞ Mg2+ ＞ NO2-. The major contents of both fine and coarse particles were crustal elements (i.e. Al, Fe, Na, Mg, K, Ca, and Sr). The species of aresenic distribute in crustal elements, and the concentration of As5+ is higher than that of As3+. This study applied HYSPLIT MODEL to find out their transportation routes by backward trajectory. According to the regions of transportation routes, this study compartmentalized Asian dusts storm transportation routes into North China area, Central China area and Northeast area. This study estimates the pollution accumulated in China area through the dust transportation routes and compares it to the sample collected in the Tainan city. The results showed that more time routes over the ocean, less pollution transport to Tainan city.
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Chou, Chun-Hung, and 周俊宏. "The impact of atmospheric transport on aerosol characteristics under the Asian monsoon in Hungchen area." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/12639716040186625696.
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碩士中山醫學大學
公共衛生學系碩士班
101
Hourly measurements of meteorological parameters (temperature, relative humidity, wind direction and wind speed), particulate and gaseous pollutants (PM10, PM2.5, O3, SO2, CO and NO2), chemical compositions of PM2.5 (water soluble ions, elemental carbon, and organic carbon), and aerosol optical parameters (scattering coefficient and vertical distribution of aerosols) were made from February 26 to April 15 2013 at Hungchen in Taiwan. The HYSPLIT and WRF models were applied to distinguish the weather condition. In this work, four types of air masses were identified as the sea land breeze circulation, northeast monsoon, western sea wind, and downwash. The first three air masses can be directly characterized as daily variations with sea wind (northwest) in daytime and land wind (northeast) in nighttime, the prevailing northeaster with strong and cold wind, and the prevailing light breeze from west, respectively. The downwash processes were verified that the occurrence of peak in biomass burning tracer concentration was consistency with the period of downwash transport in the ground station. The vertical distribution of aerosols measured from the in situ LIDAR and the vertical wind section simulated from the meteorological model were used to define the period of the downwash transport. The biomass burning pollutants from the Indo-China Peninsula were regarded as the tracer to observe the downwash transport of the upper atmosphere. The pollutant characteristics of each air mass were found in this study. The sea wind with primary photochemical pollutants led to the serious pollution at Hungchen. However, the concentrations of pollutants were quickly reduced when the wind was changed to the land wind. The pollution was related to the long range transport of polluted air from Asia in the prevailing northeasterly. During the westerly, the air quality was the best during the observed period. The ambient aerosols with the Cl-/Na+ ratio of 2.3 (similar to the ratio of 1.8 from sea salts) were characterized as the oceanic transport. The long-range transport of biomass burning from the Indo-China Peninsula affected the air quality at Hungchen through the downwash process. The aerosols were characterized as the high proportion of biomass pollutants, low ratios of NO3-/K+ and NO3-/SO42-, and a trace of crustal and sea salts species. The multi-regression analysis of aerosols radiative effects indicated that NO3- and SO42- were the largest contributions of atmospheric scattering coefficient in the local polluted air masses (sea land breeze circulation) and the long-range transport air masses (northeast monsoon and downwash), respectively.
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Hofer, Julian. "Aerosol characterization over a Central Asian site: long-term lidar profiling at Dushanbe, Tajikistan (March 2015 – August 2016)." 2020. https://ul.qucosa.de/id/qucosa%3A72461.
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For the first time, a comprehensive characterization of optical, microphysical, and cloud-relevant properties of Central Asian aerosol particles with a state-of-the-art lidar has been performed. This study fills a gap between observations in Eastern Mediterranean (e.g., in Greece, Cyprus, and Israel) and Eastern Asian (e.g, in China, Korea, and Japan) aerosol monitoring.
During the Central Asian Dust Experiment (CADEX), an automatic multiwavelength
polarization Raman lidar PollyXT was operated in Dushanbe, Tajikistan, from 17 March 2015 until 31 August 2016. During the 18-month campaign, on 487 days, lidar data has been acquired for a time period of at least 3 h. On 308 of these days, the lidar ran even longer than 20 h. 328 manually analyzed profiles of nighttime observations build the data basis of this study and cover well the annual cycle of dust and pollution aerosol layering. Thorough quality assurance and calibration efforts have been made before, during, and after the measurement campaign.
With the lidar, vertical profiles of the particle backscatter coefficient at 355 nm, 532 nm, and 1064 nm, of the particle extinction coefficient at 355 nm and 532 nm, and of the particle linear depolarization ratio at 355 nm and 532 nm wavelength were determined. From these quantities, lidar ratios and backscatter-related and extinction-related Ångström exponents were derived. Furthermore, the optical properties were converted to mass concentration and cloud-relevant parameters (CCN and INP concentration) by means of the recently developed lidar technique POLIPHON.
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Yu-LiHsiao and 蕭諭勵. "Evaluating spatial and temporal variations of aerosol optical depth, climate factors, human activities and biomass burning over Southeast Asia using satellite data." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/w99veh.
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碩士國立成功大學
環境工程學系
103
Major cities in Southeast Asia (SEA) are faced with severe air quality problems including dust, smog and haze pollution, which are mainly caused by atmospheric aerosols (smoke) from biomass burning. Technological advances in monitoring atmospheric aerosol and biomass burning have been fostered by a series of new space based satellite instruments and data products. In this study, a variety of satellite product maps of aerosol optical depth (AOD), precipitation, wind, city light, burned area (BA) and active fire were collected and processed to evaluate the spatial and temporal variations among atmospheric aerosol, climate factors, human activities and biomass burning in SEA during 2002-2011. Satellite data applied in this study includes: 1) the Moderate Resolution Imaging Spectroradiometer (MODIS) derived AOD; 2) three MODIS BA products, including the BA derived from vegetation change and land-cover classification (MCD45A1), the BA derived from active-fire (GFED4.0), and the combination of GFED4.0 and BA caused by small-scale fires (GFED4.0s); 3) the MODIS active fire data (MCD14ML); 4) the National Oceanic and Atmospheric Administration (NOAA) surface wind data; 5) the MODIS International Geosphere-Biosphere Programme (IGBP) classes land cover dataset (MCD12Q1); 6) the Global Precipitation Climatology Project (GPCP) monthly precipitation dataset; and 7) the DMSP-OLS nighttime light representing the strength of human activities. All satellite data was converted, visualized, summarized and analyzed using the spatial analyst tool within ESRI ArcGIS® 10.2. To better understand the cause and effect relationships between various causative factors and atmospheric aerosols, the results were organized into five sections. First, the spatial and temporal variations of aerosol optical depth in SEA during 2002 to 2011 were examined. High aerosol areas (HAA) located in the northern and southern intertropical zone are identified, respectively, from the monthly AOD distribution maps. The northern HAA consists of Myanmar, Vietnam, Laos, Thailand, and Cambodia, with the peak AOD months are from November to March. The southern HAA includes Malaysia, Sumatra, Java, and Kalimantan, with the peak AOD months are from May to October. Generally, the peak AOD months are consistent with the dry season in each region, which provides evidence that the temporal AOD distribution in SEA is partly related to biomass burning. Second, the recently released BA product (GFED4.0s) shows that Myanmar has the largest annual BA in north intertropical zone, followed by Cambodia, and Thailand. Burned areas in south intertropical zone are mainly distributed in Indonesia. The peak burning months are also consistent with the dry months in each region. Noted that the burning area in the northern intertropical zone is ten times higher than that found in southern intertropical zone. However, the level of annual average AOD in the southern HAA is very similar with that in the northern HAA. It is evidence that biomass burning in peatlands results in a higher emission factor of particulate matter. Third, the correlations between AOD and climate factors were assessed. The level of AOD is generally inversely proportional to precipitation, which is partly related to less biomass burning occurring during the wet seasons. The monthly average wind climatology can partly explain the large scale movement of aerosol plumes in the northern HAA during the burning months (November to next April). For the southern HAA, there is no significant correlation between wind and the spatial distribution of AOD. Fourth, the level of AOD is generally high in urban and metropolitan areas, however, there is no significant temporal correlation between AOD and the strength of human activity. Finally, to seek a quantifiable linkage between AOD and biomass burning, the study area focuses on HAAs only, and different products representing biomass burning are applied. Among the three BA products applied (MCD45A1, GFED4.0, and GFED4.0s), GFED4.0s considers both the BA identified by GFED4.0 and BA caused by small-scale fires, and can better explain the temporal and spatial distributions of AOD in HAAs (R=0.5 and 0.85 for northern and southern HAA, respectively). The correlation between commonly used MCD45A1 BA and AOD is not significant (R=0.25 and 0.58 for north and south HAA, respectively). Compared to other BA or active fire products, it was found that the MCD45A1 BA has the lowest correlation to AOD, and it is suspected that the BA derived from vegetation-change may seriously underestimate the area of burning in SEA. To better quantify the relationship between AOD and biomass burning, this study develops two simple regression models for the estimation of monthly AOD from remotely sensed burning products in HAAs. The regression model developed for northern HAA uses MCD14ML active fire data as the independent variable and obtained a R2 value of 0.57. The model developed for southern HAA uses GFED4.0s BA data as the independent variable and obtained a R2 value of 0.76. Generally, the empirical models can explain well the temporal trends of AOD in HAAs.
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Chang, Chiao-Wei, and 張巧薇. "The Susceptibility of East Asian Marine Warm Clouds to Aerosol Index During Winter and Sparing From Satellite Observation." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ga8j53.
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碩士國立臺灣大學
大氣科學研究所
105
Aerosols can affect the cloud radiative forcing by acting as the cloud condensation nuclei and subsequently changing the micro- and macro-physical properties of clouds. The classical theory states that the increase in CCN concentration results in the decrease of cloud droplet effective radius (Re), thereby inhibiting the coalescence process, which in turn may extend the cloud lifetime, enhance cloud water contents and increase the clod fraction, producing negative radiative forcing. More recent studies focusing on the aerosol-cloud interactions of shallow clouds have suggested that the cloud liquid water path does not necessarily increase with increasing aerosol loading, and the response depends on the precipitation state of the cloud and the thermodynamic conditions of the environment. It is found that the environmental condition in East Asian winter and spring is largely controlled by the monsoonal circulation and the warm sea surface temperature associated with the Kuroshio current. The environmental factors not only affect the types of low clouds but also the aerosol-cloud responses. The current study applies the co-located aerosol and cloud retrievals from the A- train satellites during 2006-2010 to investigate the aerosol-cloud interactions of marine warm clouds in East Asia in winter and spring, the seasons in which the low-level marine clouds and high aerosol pollution coexist most frequently. First, the single-layer warm clouds over the open ocean are identified based on the number of cloud layers detected by Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) and the cloud-top temperature and pressure retrieved from Moderate Resolution Imaging Spectroradiometer (MODIS). The precipitation flag retrieved from the Cloud Profiling Radar on CloudSat are also applied to separate the state of precipitation of the clouds. The clouds are then further classified based on the near-surface stability (NSS) and estimated inversion strength (EIS) to explore variation of the susceptibility of cloud properties under different environmental conditions. As cold continental air moves onto the warm ocean, it destabilizes the marine boundary layer, resulting in the formation of more shallow convective clouds. As the large-scale subsidence associated with the southeastward movement of Siberian high strengthens, the type of clouds transfer from broken clouds into continuous clouds. The cloud susceptibility is stronger for precipitating clouds and under unstable conditions. For non-precipitating clouds, LWP decreases slightly under the stable condition and increases in unstable condition with increasing aerosols. For precipitating clouds, LWP increases with increasing aerosols and increases more under unstable condition. Note that the susceptibility of precipitating clouds is stronger than non- precipitating ones, it results in larger cloud optical depth and cloud albedo. In the future, the susceptibility of precipitation of marine warm clouds will be analyzed by high resolution model in purpose of understanding the unique aerosol-cloud interaction among different cloud types. In addition, the aerosol-cloud radiative forcing during winter and spring in East Asia will also be estimated.