Journal articles on the topic 'Atmosphere-lake interaction'

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1

Djolov, G. "Hydrothermodynamic interaction between lake and atmosphere." Boundary-Layer Meteorology 61, no. 1-2 (October 1992): 205. http://dx.doi.org/10.1007/bf02034003.

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2

Turchak, Leonid I., and Maria I. Gritsevich. "Meteoroids Interaction With The Earth Atmosphere." Journal of Theoretical and Applied Mechanics 44, no. 4 (December 1, 2014): 15–28. http://dx.doi.org/10.2478/jtam-2014-0020.

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Abstract In this study we evaluate meteoroid mass and its other properties based on the observed atmospheric trajectory. With account for aerodynamics, we formulate a problem by introducing key dimensionless parameters in the model, responsible for the drag, mass loss and rotation of meteoroid. The proposed model is suitable to categorize various impact events in terms of meteor survivability and impact damage and thus, to analyze consequences that accompany collisions of cosmic bodies with planetary atmosphere and surface. The different types of events, namely, formation of a massive single crater (Barringer, Lonar Lake), dispersion of craters and meteorites over a large area (Sikhote-Alin), absent of craters and meteorites, but huge damage (Tunguska) are considered as illustrative examples. The proposed approach helps to summarize the data on existing terrestrial impacts and to formulate recommendations for further studies valuable for planetary defence. It also significantly increases chances of successful meteorite recoveries in future. In other words, the study represents a ’cheap’ possibility to probe cosmic matter reaching planetary surface and it complements results of sample-return missions bringing back pristine samples of the materials.
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3

Gao, Yanhong, Fei Chen, Gonzalo Miguez-Macho, and Xia Li. "Understanding precipitation recycling over the Tibetan Plateau using tracer analysis with WRF." Climate Dynamics 55, no. 9-10 (August 29, 2020): 2921–37. http://dx.doi.org/10.1007/s00382-020-05426-9.

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Abstract The precipitation recycling (PR) ratio is an important indicator that quantifies the land-atmosphere interaction strength in the Earth system’s water cycle. To better understand how the heterogeneous land surface in the Tibetan Plateau (TP) contributes to precipitation, we used the water-vapor tracer (WVT) method coupled with the Weather Research and Forecasting (WRF) regional climate model. The goals were to quantify the PR ratio, in terms of annual mean, seasonal variability and diurnal cycle, and to address the relationships of the PR ratio with lake treatments and precipitation amount. Simulations showed that the PR ratio increases from 0.1 in winter to 0.4 in summer when averaged over the TP with the maxima centered at the headwaters of three major rivers (Yangtze, Yellow and Mekong). For the central TP, the highest PR ratio rose to over 0.8 in August, indicating that most of the precipitation was recycled via local evapotranspiration in summer. The larger daily mean and standard deviation of the PR ratio in summer suggested a stronger effect of land-atmosphere interactions on precipitation in summer than in winter. Despite the relatively small spatial extent of inland lakes, the treatment of lakes in WRF significantly impacted the calculation of the PR ratio over the TP, and correcting lake temperature substantially improved both precipitation and PR ratio simulations. There was no clear relationship between PR ratio and precipitation amount; however, a significant positive correlation between PR and convective precipitation was revealed. This study is beneficial for the understanding of land-atmosphere interaction over high mountain regions.
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Wang, Mengxiao, Lijuan Wen, Zhaoguo Li, Matti Leppäranta, Victor Stepanenko, Yixin Zhao, Ruijia Niu, Liuyiyi Yang, and Georgiy Kirillin. "Mechanisms and effects of under-ice warming water in Ngoring Lake of Qinghai–Tibet Plateau." Cryosphere 16, no. 9 (September 9, 2022): 3635–48. http://dx.doi.org/10.5194/tc-16-3635-2022.

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Abstract. The seasonal ice cover in lakes of the Qinghai–Tibet Plateau is a transient and vulnerable part of the cryosphere, whose characteristics depend on the regional climate: strong solar radiation in the context of the dry and cold environment because of the high altitude and relatively low latitude. We use the first under-ice temperature observations from the largest Tibetan freshwater lake, Ngoring Lake, and a one-dimensional lake model to quantify the mechanism of solar thermal accumulation under ice, which relies on the ice optical properties and weather conditions, as well as the effect of the accumulated heat on the land–atmosphere heat exchange after the ice breakup. The model was able to realistically simulate the feature of the Ngoring Lake thermal regime: the “summer-like” temperature stratification with temperatures exceeding the maximum density point of 3.98 ∘C across the bulk of the freshwater column. A series of sensitivity experiments revealed solar radiation was the major source of under-ice warming and demonstrated that the warming phenomenon was highly sensitive to the optical properties of ice. The heat accumulated under ice contributed to the heat release from the lake to the atmosphere for 1–2 months after ice-off, increasing the upward sensible and latent surface heat fluxes on average by ∼ 50 and ∼ 80 W m−2, respectively. Therefore, the delayed effect of heat release on the land–atmosphere interaction requires an adequate representation in regional climate modeling of the Qinghai–Tibet Plateau and other lake-rich alpine areas.
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Chen, Haishan, Bo Yu, Botao Zhou, Wanxin Zhang, and Jie Zhang. "Role of Local Atmospheric Forcing and Land–Atmosphere Interaction in Recent Land Surface Warming in the Midlatitudes over East Asia." Journal of Climate 33, no. 6 (March 15, 2020): 2295–309. http://dx.doi.org/10.1175/jcli-d-18-0856.1.

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AbstractSignificant summer land surface warming has been observed in the middle latitudes over East Asia, especially after the mid-1990s, which has evidently affected the East Asian weather and climate. Using multisource observations and reanalysis data during 1979–2013, this study explores the possible reasons for recent land surface warming over this region by considering atmospheric forcing and regional land–atmosphere interaction related to extratropical cyclones (ECs). Results show that there is a close relationship between land surface warming and weakened ECs over East Asia. Recent land surface warming was attributed to local atmospheric forcing and feedback of land–atmosphere interaction associated with weakened ECs. The abnormal large-scale circulation associated with anomalous ECs produced evident dynamic forcing on the land surface. Weakened ECs are usually accompanied by an abnormal high pressure system and anticyclonic circulation around Lake Baikal, which benefit the intensification of anomalous southerly wind in the rear of the anomalous anticyclone, leading to positive temperature advection and temperature increase over East Asia. Meanwhile, the anomalous adiabatic warming caused by abnormal descending motion associated with the anticyclonic anomaly also contributes to local warming. The feedback of local land–atmosphere interaction plays an important role in land surface warming. Weakened ECs increase both incident solar radiation and precipitation. The increased precipitation reduces the soil moisture and in turn weakens the surface evaporation and local cooling effect, resulting in land surface warming. Our findings are helpful for better understanding the mechanisms responsible for recent summer land surface warming over East Asia as well as its climatic effects.
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6

Gemilang, Annisa, Huda Nurjanti, and Firmansam Bastaman. "Lanskap Agrowisata Kopi Sumedang Sebagai Kolaborasi Peningkatan Perkebunan Rakyat Dan Perlindungan Lahan Danau Sunyayuri." Composite: Jurnal Ilmu Pertanian 3, no. 02 (December 31, 2021): 68–77. http://dx.doi.org/10.37577/composite.v3i02.361.

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called Kopi Buhun. Buhun Coffee is a type of Arabica coffee which is a single origin "special tea coffee". In developing Buhun coffee, land is needed that can be planted with coffee. This land is not only a coffee plantation but can become a tourist attraction that can educate, increase recreation and protect the environment besides that it can economically increase the income of residents around agrotourism. In general, the land of Lake Sunyayuri, Cimarias Village, Pamulihan District, Sumedang Regency is an area that has the potential to become a tourist spot with an artificial lake, and a panoramic view of the hills surrounding the lake with a beautiful and calming atmosphere. The productivity of Indonesian coffee is still low compared to the potential that can be increased. The need for plantation land, especially coffee, is still lacking. Utilization of abandoned forest areas in areas with coffee potential can still be carried out, including utilizing the Pamulihan Cekdam area. What is the form of the Sumedang Coffee Agrotourism design in utilizing the existing potential into plantation tourism that provides interesting tourist experiences, recreational facilities, and social interaction as well as coffee education for visitors and the community about how to cultivate coffee from nurseries to products that can be enjoyed and provide a source of income for local communities while preserving the environment?
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7

Jiang, Haoyu, Yingyao He, Yiqun Wang, Sheng Li, Bin Jiang, Luca Carena, Xue Li, et al. "Formation of organic sulfur compounds through SO<sub>2</sub>-initiated photochemistry of PAHs and dimethylsulfoxide at the air-water interface." Atmospheric Chemistry and Physics 22, no. 6 (April 1, 2022): 4237–52. http://dx.doi.org/10.5194/acp-22-4237-2022.

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Abstract. The presence of organic sulfur compounds (OS) at the water surface acting as organic surfactants, may influence the air-water interaction and contribute to new particle formation in the atmosphere. However, the impact of ubiquitous anthropogenic pollutant emissions, such as SO2 and polycyclic aromatic hydrocarbons (PAHs) on the formation of OS at the air-water interface still remains unknown. Here, we observe large amounts of OS formation in the presence of SO2, upon irradiation of aqueous solutions containing typical PAHs, such as pyrene (PYR), fluoranthene (FLA), and phenanthrene (PHE) as well as dimethylsulfoxide (DMSO). We observe rapid formation of several gaseous OSs from light-induced heterogeneous reactions of SO2 with either DMSO or a mixture of PAHs and DMSO (PAHs/DMSO), and some of these OSs (e.g. methanesulfonic acid) are well established secondary organic aerosol (SOA) precursors. A myriad of OSs and unsaturated compounds are produced and detected in the aqueous phase. The tentative reaction pathways are supported by theoretical calculations of the Gibbs energy of reactions. Our findings provide new insights into potential sources and formation pathways of OSs occurring at the water (sea, lake, river) surface, that should be considered in future model studies for a better representation of the air-water interaction and SOA formation processes.
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8

Pickarski, N., O. Kwiecien, D. Langgut, and T. Litt. "Abrupt climate and vegetation variability of eastern Anatolia during the last glacial." Climate of the Past 11, no. 11 (November 2, 2015): 1491–505. http://dx.doi.org/10.5194/cp-11-1491-2015.

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Abstract. Detailed analyses of the Lake Van pollen, Ca / K ratio, and stable oxygen isotope record allow the identification of millennial-scale vegetation and environmental changes in eastern Anatolia throughout the last glacial (~ 111.5–11.7 ka BP). The climate of the last glacial was cold and dry, indicated by low arboreal pollen (AP) levels. The driest and coldest period corresponds to Marine Isotope Stage (MIS) 2 (~ 28–14.5 ka BP), which was dominated by highest values of xerophytic steppe vegetation. Our high-resolution multi-proxy record shows rapid expansions and contractions of tree populations that reflect variability in temperature and moisture availability. These rapid vegetation and environmental changes can be related to the stadial-interstadial pattern of Dansgaard–Oeschger (DO) events as recorded in the Greenland ice cores. Periods of reduced moisture availability were characterized by enhanced occurrence of xerophytic species and high terrigenous input from the Lake Van catchment area. Furthermore, the comparison with the marine realm reveals that the complex atmosphere–ocean interaction can be explained by the strength and position of the westerlies, which are responsible for the supply of humidity in eastern Anatolia. Influenced by the diverse topography of the Lake Van catchment, more pronounced DO interstadials (e.g., DO 19, 17–16, 14, 12 and 8) show the strongest expansion of temperate species within the last glacial. However, Heinrich events (HE), characterized by highest concentrations of ice-rafted debris (IRD) in marine sediments, cannot be separated from other DO stadials based on the vegetation composition in eastern Anatolia. In addition, this work is a first attempt to establish a continuous microscopic charcoal record for the last glacial in the Near East. It documents an immediate response to millennial-scale climate and environmental variability and enables us to shed light on the history of fire activity during the last glacial.
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9

Pickarski, N., O. Kwiecien, D. Langgut, and T. Litt. "Abrupt climate variability of eastern Anatolia vegetation during the last glacial." Climate of the Past Discussions 11, no. 4 (July 22, 2015): 3341–73. http://dx.doi.org/10.5194/cpd-11-3341-2015.

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Abstract. Detailed analyses of the Lake Van pollen and stable oxygen isotope record allow the identification of millennial-scale vegetation and environmental changes in eastern Anatolia throughout the last glacial. The climate within the last glacial period (∼75–15 ka BP) was cold and dry, with low arboreal pollen (AP) levels. The driest and coldest period corresponds to Marine Isotope Stage (MIS) 2 (∼28–14.5 ka BP) dominated by the highest values of xerophytic steppe vegetation. Our high-resolution multi proxy record shows rapid expansions and contractions that mimic the stadial-interstadial pattern of the Dansgaard–Oeschger (DO) events as recorded in the Greenland ice cores, and thus, provide a linkage to North Atlantic climate oscillations. Periods of reduced moisture availability characterized at Lake Van by enhanced xerophytic species correlates well with increase in ice-rafted debris (IRD) and a decrease of sea surface temperature (SST) in the North Atlantic. Furthermore, comparison with the marine realm reveals that the complex atmosphere–ocean interaction can be recognized by the strength and position of the westerlies in eastern Anatolia. Influenced by rough topography at Lake Van, the expansion of temperate species (e.g. deciduous Quercus) was stronger during interstadials DO 19, 17–16, 14, 12 and 8. However, Heinrich events (HE), characterized by highest concentrations of ice-rafted debris in marine sediments, are identified in eastern Anatolia by AP values not lower and high steppe components not more abundant than during DO stadials. In addition, this work is a first attempt to establish a continuous microscopic charcoal record over the last glacial in the Near East, which documents an initial immediate response to millennial-scale climate and environmental variability and enables the shed light on the history of fire activity during the last glacial.
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10

Pandey, Siddharth, Jonathan Clarke, Preeti Nema, Rosalba Bonaccorsi, Sanjoy Som, Mukund Sharma, Binita Phartiyal, et al. "Ladakh: diverse, high-altitude extreme environments for off-earth analogue and astrobiology research." International Journal of Astrobiology 19, no. 1 (June 13, 2019): 78–98. http://dx.doi.org/10.1017/s1473550419000119.

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AbstractThis paper highlights unique sites in Ladakh, India, investigated during our 2016 multidisciplinary pathfinding expedition to the region. We summarize our scientific findings and the site's potential to support science exploration, testing of new technologies and science protocols within the framework of astrobiology research. Ladakh has several accessible, diverse, pristine and extreme environments at very high altitudes (3000–5700 m above sea level). These sites include glacial passes, sand dunes, hot springs and saline lake shorelines with periglacial features. We report geological observations and environmental characteristics (of astrobiological significance) along with the development of regolith-landform maps for cold high passes. The effects of the diurnal water cycle on salt deliquescence were studied using the ExoMars Mission instrument mockup: HabitAbility: Brines, Irradiance and Temperature (HABIT). It recorded the existence of an interaction between the diurnal water cycle in the atmosphere and salts in the soil (which can serve as habitable liquid water reservoirs). Life detection assays were also tested to establish the best protocols for biomass measurements in brines, periglacial ice-mud and permafrost melt water environments in the Tso-Kar region. This campaign helped confirm the relevance of clays and brines as interest targets of research on Mars for biomarker preservation and life detection.
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11

Conry, Patrick, Ashish Sharma, Mark J. Potosnak, Laura S. Leo, Edward Bensman, Jessica J. Hellmann, and Harindra J. S. Fernando. "Chicago’s Heat Island and Climate Change: Bridging the Scales via Dynamical Downscaling." Journal of Applied Meteorology and Climatology 54, no. 7 (July 2015): 1430–48. http://dx.doi.org/10.1175/jamc-d-14-0241.1.

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AbstractThe interaction of global climate change and urban heat islands (UHI) is expected to have far-reaching impacts on the sustainability of the world’s rapidly growing urban population centers. Given that a wide range of spatiotemporal scales contributed by meteorological forcing and complex surface heterogeneity complicates UHI, a multimodel nested approach is used in this paper to study climate-change impacts on the Chicago, Illinois, UHI, covering a range of relevant scales. One-way dynamical downscaling is used with a model chain consisting of global climate (Community Atmosphere Model), regional climate (Weather Research and Forecasting Model), and microscale (“ENVI-met”) models. Nested mesoscale and microscale models are evaluated against the present-day observations (including a dedicated urban miniature field study), and the results favorably demonstrate the fidelity of the downscaling techniques that were used. A simple building-energy model is developed and used in conjunction with microscale-model output to calculate future energy demands for a building, and a substantial increase (as much as 26% during daytime) is noted for future (~2080) climate. Although winds and lake-breeze circulation for future climate are favorable for reducing energy usage by 7%, the benefits are outweighed by such factors as exacerbated UHI and air temperature. An adverse change in human-comfort indicators is also noted in the future climate, with 92% of the population experiencing thermal discomfort. The model chain that was used has general applicability for evaluating climate-change impacts on city centers and, hence, for urban-sustainability studies.
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Ganbat, Danaa, and Gantuya Ganbat. "Results of simulations of atmosphere-lake interactions using numerical model." Embedded Selforganising Systems 9, no. 3 (October 19, 2022): 37–38. http://dx.doi.org/10.14464/ess.v9i3.535.

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Lakes influence the regional atmosphere through modifying thermodynamic characteristics. This study examines the effects of the Baikal lake on meteorological parameters in summertime using the numerical model. Diurnal variations in the lakes’ impact on the atmosphere are found through changing the surface energy budget, which includes changes in sensible and latent heat fluxes. The changes in heat fluxes cause relatively lower surface temperature which leads to a shallow boundary layer over the lake surfaces. Greater heat capacity in water bodies compared to grasslands causes slower heating and cooling rates in the lakes. The amplitude of air temperature over the lake surfaces is smaller than that over the grasslands. Lakes promote diverging winds near the ground, furthermore, tend to stabilize the overlying atmosphere in the summertime.
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Santisteban, María, Ana Teresa Luís, José Antonio Grande, Javier Aroba, José Miguel Dávila, Aguasanta Miguel Sarmiento, Juan Carlos Fortes, Francisco Cordoba, and Ángel Mariano Rodriguez-Pérez. "Hydrochemical Characterization of an Acid Mine Effluent from Concepcion Mine Using Classical Statistic and Fuzzy Logic Techniques." Minerals 12, no. 4 (April 11, 2022): 464. http://dx.doi.org/10.3390/min12040464.

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This work focuses on the physical-chemical characterization of a mining effluent affected by acid mine drainage (AMD) from its source to the confluence in the Odiel river, one of the most polluted rivers by AMD worldwide, in order to understand the reactions involved in the modifications in the chemical characteristics of water and precipitates resulting from water–rock–atmosphere interaction in an environment highly affected by mining activity without corrective measures. The channel starts in an open pit lake through one of the Concepción Mine main galleries, located in the Iberian Pyrite Belt, about 10 km northwest of Rio Tinto mining complex (southwest Spain). This gallery intercepts one of the largest and oldest underground mining work locations called “gallery Carmen”, allowing the exit of AMD affected waters. This channel is the first AMD polluting source in the Odiel basin. Thus, at the end of the rainy season, we conducted water sampling along this channel, from its source to its mouth, to further analyse its characterization and interpret the cause–effect relationships through the application of Fuzzy Logic and classical statistics tools. The interdependent relationship between the measured physicochemical parameters are set in order to propose a model, capable of describing the evolution of contaminants in response to the processes and reactions taking place within the affected channel and the Odiel river. The present work concluded the existence of natural attenuation processes for the mining channel, despite the entrances of other drainages in the AMD channel with different hydrochemical characteristics imposing modifications on it. This indicates that these media have a high vulnerability to external stimuli.
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14

Laiti, L., D. Zardi, M. de Franceschi, and G. Rampanelli. "Analysis of the diurnal development of the <i>Ora del Garda</i> wind in the Alps from airborne and surface measurements." Atmospheric Chemistry and Physics Discussions 13, no. 7 (July 18, 2013): 19121–71. http://dx.doi.org/10.5194/acpd-13-19121-2013.

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Abstract. A lake-breeze and valley-wind coupled circulation system, known as Ora del Garda, typically arises in the late morning from the northern shorelines of Lake Garda (southeastern Italian Alps), and then channels into the Sarca and Lakes valleys to the north. After flowing over an elevated saddle, in the early afternoon this wind breaks out from the west into the nearby Adige Valley, hindering the regular development of the local up-valley wind by producing a strong and gusty anomalous flow in the area. Two targeted flights of an equipped motorglider were performed in the morning and afternoon of 23 August 2001 in the above valleys, exploring selected vertical slices of the atmosphere, from the lake's shore to the area where the two local airflows interact. At the same time, surface observations were collected during an intensive field measurement campaign held in the interaction area, as well as from routinely-operated weather stations disseminated along the whole study area, allowing the analysis of the different stages of the Ora del Garda development. From airborne measurements, an atmospheric boundary-layer (ABL) vertical structure, typical of deep Alpine valleys, was detected in connection with the wind flow, with rather shallow (∼500 m) convective mixed layers surmounted by deeper, weakly stable layers. On the other hand, close to the lake's shoreline the ABL was found to be stabilized down to very low heights, as an effect of the onshore advection of cold air by the lake breeze. Airborne potential temperature observations were mapped over high-resolution 3-D grids for each valley section explored by the flights, using a geostatistical technique called residual kriging (RK). RK-regridded fields revealed fine-scale features and inhomogeneities of ABL thermal structures associated with the complex thermally-driven wind field developing in the valleys. The combined analysis of surface observations and RK-interpolated fields revealed an irregular propagation of the lake-breeze front in the lower part of the valley, and cross-valley thermal asymmetries amenable both to the differential solar heating of the valley slopes and to the valley curvature in its upper part. The overflowing of the potentially cooler Ora del Garda air from the Lakes Valley in the afternoon produces a strong katabatic wind at the bottom of the underlying Adige Valley, which blows in cross-valley (i.e. westerly) direction and impinges on the opposite eastern valley sidewall. RK-regridded potential temperature field highlighted that this phenomenon gives origin to a "hydraulic jump" flow structure in the urban area north of the city of Trento, leading to the down-stream formation of a ∼1300 m deep well-mixed layer. The improved knowledge of the typical Ora del Garda flow patterns and associated ABL structures, deriving from the combined analysis of surface and airborne observations, has practical application in air quality forecasting for the study area, for it helps in the understanding of pollution transport and dispersion processes by thermally-driven winds in the region. Moreover, 3-D meteorological fields produced by RK are likely to be an excellent basis for comparison with results from high-resolution numerical simulations, as they provide a degree of spatial detail that is fully comparable to the spatial scales resolved by large-eddy simulations.
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15

Huziy, O., and L. Sushama. "Lake–river and lake–atmosphere interactions in a changing climate over Northeast Canada." Climate Dynamics 48, no. 9-10 (July 12, 2016): 3227–46. http://dx.doi.org/10.1007/s00382-016-3260-y.

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16

Long, Z., W. Perrie, J. Gyakum, D. Caya, and R. Laprise. "Northern Lake Impacts on Local Seasonal Climate." Journal of Hydrometeorology 8, no. 4 (August 1, 2007): 881–96. http://dx.doi.org/10.1175/jhm591.1.

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Abstract It is well known that large lakes can perturb local weather and climate through mesoscale circulations, for example, lake effects on storms and lake breezes, and the impacts on fluxes of heat, moisture, and momentum. However, for both large and small lakes, the importance of atmosphere–lake interactions in northern Canada is largely unknown. Here, the Canadian Regional Climate Model (CRCM) is used to simulate seasonal time scales for the Mackenzie River basin and northwest region of Canada, coupled to simulations of Great Bear and Great Slave Lakes using the Princeton Ocean Model (POM) to examine the interactions between large northern lakes and the atmosphere. The authors consider the lake impacts on the local water and energy cycles and on regional seasonal climate. Verification of model results is achieved with atmospheric sounding and surface flux data collected during the Canadian Global Energy and Water Cycle Experiment (GEWEX) program. The coupled atmosphere–lake model is shown to be able to successfully simulate the variation of surface heat fluxes and surface water temperatures and to give a good representation of the vertical profiles of water temperatures, the warming and cooling processes, and the lake responses to the seasonal and interannual variation of surface heat fluxes. These northern lakes can significantly influence the local water and energy cycles.
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17

Xue, Pengfei, Jeremy S. Pal, Xinyu Ye, John D. Lenters, Chenfu Huang, and Philip Y. Chu. "Improving the Simulation of Large Lakes in Regional Climate Modeling: Two-Way Lake–Atmosphere Coupling with a 3D Hydrodynamic Model of the Great Lakes." Journal of Climate 30, no. 5 (February 14, 2017): 1605–27. http://dx.doi.org/10.1175/jcli-d-16-0225.1.

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Abstract Accurate representations of lake–ice–atmosphere interactions in regional climate modeling remain one of the most critical and unresolved issues for understanding large-lake ecosystems and their watersheds. To date, the representation of the Great Lakes two-way interactions in regional climate models is achieved with one-dimensional (1D) lake models applied at the atmospheric model lake grid points distributed spatially across a 2D domain. While some progress has been made in refining 1D lake model processes, such models are fundamentally incapable of realistically resolving a number of physical processes in the Great Lakes. In this study, a two-way coupled 3D lake-ice–climate modeling system [Great Lakes–Atmosphere Regional Model (GLARM)] is developed to improve the simulation of large lakes in regional climate models and accurately resolve the hydroclimatic interactions. Model results are compared to a wide variety of observational data and demonstrate the unique skill of the coupled 3D modeling system in reproducing trends and variability in the Great Lakes regional climate, as well as in capturing the physical characteristics of the Great Lakes by fully resolving the lake hydrodynamics. Simulations of the climatology and spatiotemporal variability of lake thermal structure and ice are significantly improved over previous coupled, 1D simulations. At seasonal and annual time scales, differences in model results are primarily observed for variables that are directly affected by lake surface temperature (e.g., evaporation, precipitation, sensible heat flux) while no significant differences are found in other atmospheric variables (e.g., solar radiation, cloud cover). Underlying physical mechanisms for the simulation improvements using GLARM are also discussed.
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Deng, Bin, Shoudong Liu, Wei Xiao, Wei Wang, Jiming Jin, and Xuhui Lee. "Evaluation of the CLM4 Lake Model at a Large and Shallow Freshwater Lake*." Journal of Hydrometeorology 14, no. 2 (April 1, 2013): 636–49. http://dx.doi.org/10.1175/jhm-d-12-067.1.

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Abstract Models of lake physical processes provide the lower flux boundary conditions for numerical predictions of weather and climate in lake basins. So far, there have been few studies on evaluating lake model performance at the diurnal time scale and against flux observations. The goal of this paper is to evaluate the National Center for Atmospheric Research Community Land Model version 4–Lake, Ice, Snow and Sediment Simulator using the eddy covariance and water temperature data obtained at a subtropical freshwater lake, Lake Taihu, in China. Both observations and model simulations reveal that convective overturning was commonplace at night and timed when water switched from being statically stable to being unstable. By reducing the water thermal diffusivity to 2% of the value calculated with the Henderson–Sellers parameterization, the model was able to reproduce the observed diurnal variations in water surface temperature and in sensible and latent heat fluxes. The small diffusivity suggests that the drag force of the sediment layer in this large (2500 km2) and shallow (2-m depth) lake may be strong, preventing unresolved vertical motions and suppressing wind-induced turbulence. Model results show that a large fraction of the incoming solar radiation energy was stored in the water during the daytime, and the stored energy was diffused upward at night to sustain sensible and latent heat fluxes to the atmosphere. Such a lake–atmosphere energy exchange modulated the local climate at the daily scale in this shallow lake, which is not seen in deep lakes where dominant lake–atmosphere interactions often occur at the seasonal scale.
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Thomas, Blaine C., and Jonathan E. Martin. "A Synoptic Climatology and Composite Analysis of the Alberta Clipper." Weather and Forecasting 22, no. 2 (April 1, 2007): 315–33. http://dx.doi.org/10.1175/waf982.1.

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Abstract Surface and upper-air analyses from the ECMWF Tropical Ocean Global Atmosphere (TOGA) dataset are used to construct a climatology of 177 Alberta clippers over 15 boreal cold seasons (October–March) from 1986/87 to 2000/01. The Alberta clipper (hereafter simply clipper) occurs most frequently during December and January and substantially less frequently during October and March. These cyclones generally move southeastward from the lee of the Canadian Rockies toward or just north of Lake Superior before progressing eastward into southeastern Canada or the northeastern United States, with less than 10% of the cases in the climatology tracking south of the Great Lakes. Characteristics of the structure and evolution of clippers during a 36-h period leading up to departure of the cyclone from the lee of the Canadian Rockies and a 60-h period after departure as the cyclone traverses central and eastern North America are examined through composite analyses. Over the course of the predeparture period, a cyclone over the Gulf of Alaska approaches the west coast of North America, and through its interaction with the mountainous terrain of western North America spawns a surface lee trough, characterized by a thermal ridge at 850 hPa, to the east of the Canadian Rockies. This thermal ridge dampens considerably as the composite clipper moves into central North America away from the immediate lee of the Canadian Rockies. The composite clipper system evolves from a lee cyclone with its nonclassical thermal structure to a more classically structured midlatitude cyclone as it moves through central and eastern North America largely as a result of rotation of the low-level thermal gradient and the increasing westward tilt with height of the composite clipper over the last 36 h of the postdeparture period. The thermal gradient rotation is dynamically linked to convergence of the along-isentrope component of the Q vector and thus to the ascent that sustains the clipper and creates some of its characteristic sensible weather elements. Such dynamical forcing is a direct consequence of the persistent westward displacement of the 500-hPa vorticity maximum with respect to the composite clipper sea level pressure minimum that characterizes the postdeparture period.
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Chatain, Audrey, Scot C. R. Rafkin, Alejandro Soto, Ricardo Hueso, and Aymeric Spiga. "Air–Sea Interactions on Titan: Effect of Radiative Transfer on the Lake Evaporation and Atmospheric Circulation." Planetary Science Journal 3, no. 10 (October 1, 2022): 232. http://dx.doi.org/10.3847/psj/ac8d0b.

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Abstract Titan’s northern high latitudes host many large hydrocarbon lakes. Like water lakes on Earth, Titan’s lakes are constantly subject to evaporation. This process strongly affects the atmospheric methane abundance, the atmospheric temperature, the lake mixed layer temperature, and the local wind circulation. In this work we use a 2D atmospheric mesoscale model coupled to a slab lake model to investigate the effect of solar and infrared radiation on the exchange of energy and methane between Titan’s lakes and atmosphere. The magnitude of solar radiation reaching the surface of Titan through its thick atmosphere is only a few watts per square meter. However, we find that this small energy input is important and is comparable in absolute magnitude to the latent and sensible heat fluxes, as suggested in a study by Rafkin & Soto (2020). The implementation of a gray radiative scheme in the model confirms the importance of radiation when studying lakes at the surface of Titan. Solar and infrared radiation change the energy balance of the system leading to an enhancement of the methane evaporation rate, an increase of the equilibrium lake temperature almost completely determined by its environment (humidity, insolation, and background wind), and a strengthening of the local sea breeze, which undergoes diurnal variations. The sea breeze efficiently transports methane vapor horizontally, from the lake to the land, and vertically due to rising motion along the sea breeze front and due to radiation-induced turbulence over the land.
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21

Potes, M., R. Salgado, M. J. Costa, M. Morais, D. Bortoli, I. Kostadinov, and I. Mammarella. "Lake–atmosphere interactions at Alqueva reservoir: a case study in the summer of 2014." Tellus A: Dynamic Meteorology and Oceanography 69, no. 1 (January 1, 2017): 1272787. http://dx.doi.org/10.1080/16000870.2016.1272787.

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22

Şen, Z., M. Kadioğlu, and E. Batur. "Cluster regression model and level fluctuation features of Van Lake, Turkey." Annales Geophysicae 17, no. 2 (February 28, 1999): 273–79. http://dx.doi.org/10.1007/s00585-999-0273-4.

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Abstract. Lake water levels change under the influences of natural and/or anthropogenic environmental conditions. Among these influences are the climate change, greenhouse effects and ozone layer depletions which are reflected in the hydrological cycle features over the lake drainage basins. Lake levels are among the most significant hydrological variables that are influenced by different atmospheric and environmental conditions. Consequently, lake level time series in many parts of the world include nonstationarity components such as shifts in the mean value, apparent or hidden periodicities. On the other hand, many lake level modeling techniques have a stationarity assumption. The main purpose of this work is to develop a cluster regression model for dealing with nonstationarity especially in the form of shifting means. The basis of this model is the combination of transition probability and classical regression technique. Both parts of the model are applied to monthly level fluctuations of Lake Van in eastern Turkey. It is observed that the cluster regression procedure does preserve the statistical properties and the transitional probabilities that are indistinguishable from the original data.Key words. Hydrology (hydrologic budget; stochastic processes) · Meteorology and atmospheric dynamics (ocean-atmosphere interactions)
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23

Potes, M., M. J. Costa, and R. Salgado. "Satellite remote sensing of water turbidity in Alqueva reservoir and implications on lake modelling." Hydrology and Earth System Sciences 16, no. 6 (June 6, 2012): 1623–33. http://dx.doi.org/10.5194/hess-16-1623-2012.

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Abstract. The quality control and monitoring of surface freshwaters is crucial, since some of these water masses constitute essential renewable water resources for a variety of purposes. In addition, changes in the surface water composition may affect the physical properties of lake water, such as temperature, which in turn may impact the interactions of the water surface with the lower atmosphere. The use of satellite remote sensing to estimate the water turbidity of Alqueva reservoir, located in the south of Portugal, is explored. A validation study of the satellite derived water leaving spectral reflectance is firstly presented, using data taken during three field campaigns carried out during 2010 and early 2011. Secondly, an empirical algorithm to estimate lake water surface turbidity from the combination of in situ and satellite measurements is proposed. Finally, the importance of water turbidity on the surface energy balance is tested in the form of a study of the sensitivity of a lake model to the extinction coefficient of water (estimated from turbidity), showing that this is an important parameter that affects the lake surface temperature.
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24

Huziy, Oleksandr, Bernardo Teufel, Laxmi Sushama, and Ram Yerubandi. "Heavy Lake-Effect Snowfall Changes and Mechanisms for the Laurentian Great Lakes Region." Atmosphere 12, no. 12 (November 27, 2021): 1577. http://dx.doi.org/10.3390/atmos12121577.

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Heavy lake-effect snowfall (HLES) events are snowfall events enhanced by interactions between lakes and overlying cold air. Significant snowfall rates and accumulations caused during such events disrupt socioeconomic activities and sometimes lead to lethal consequences. The aim of this study is to assess projected changes to HLES by the end of the century (2079–2100) using a regional climate model for the first time with 3D representation for the Laurentian Great Lakes. When compared to observations over the 1989–2010 period, the model is able to realistically reproduce key mechanisms and characteristics of HLES events, thus increasing confidence in future projections. Projected changes to the frequency and amount of HLES suggest decreasing patterns, during the onset, active and decline phases of HLES. Despite reduced lake ice cover that will allow enhanced lake–atmosphere interactions favouring HLES, the warmer temperatures and associated increase in liquid to solid precipitation ratio along with reduced cold air outbreaks contribute to reduced HLES in the future climate. Analysis of the correlation patterns for current and future climates further supports the weaker impact of lake ice fraction on HLES in future climates. Albeit the decreases in HLES frequency and intensity and projected increases in extreme snowfall events (resulting from all mechanisms) raise concerns for impacts on the transportation, infrastructure and hydropower sectors in the region.
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25

Penenko, V. V., and E. A. Tsvetova. "Mathematical models for the study of interactions in the system lake baikal-atmosphere of the region." Journal of Applied Mechanics and Technical Physics 40, no. 2 (March 1999): 308–16. http://dx.doi.org/10.1007/bf02468528.

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26

Willeit, Matteo, and Andrey Ganopolski. "PALADYN v1.0, a comprehensive land surface–vegetation–carbon cycle model of intermediate complexity." Geoscientific Model Development 9, no. 10 (October 28, 2016): 3817–57. http://dx.doi.org/10.5194/gmd-9-3817-2016.

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Abstract. PALADYN is presented; it is a new comprehensive and computationally efficient land surface–vegetation–carbon cycle model designed to be used in Earth system models of intermediate complexity for long-term simulations and paleoclimate studies. The model treats in a consistent manner the interaction between atmosphere, terrestrial vegetation and soil through the fluxes of energy, water and carbon. Energy, water and carbon are conserved. PALADYN explicitly treats permafrost, both in physical processes and as an important carbon pool. It distinguishes nine surface types: five different vegetation types, bare soil, land ice, lake and ocean shelf. Including the ocean shelf allows the treatment of continuous changes in sea level and shelf area associated with glacial cycles. Over each surface type, the model solves the surface energy balance and computes the fluxes of sensible, latent and ground heat and upward shortwave and longwave radiation. The model includes a single snow layer. Vegetation and bare soil share a single soil column. The soil is vertically discretized into five layers where prognostic equations for temperature, water and carbon are consistently solved. Phase changes of water in the soil are explicitly considered. A surface hydrology module computes precipitation interception by vegetation, surface runoff and soil infiltration. The soil water equation is based on Darcy's law. Given soil water content, the wetland fraction is computed based on a topographic index. The temperature profile is also computed in the upper part of ice sheets and in the ocean shelf soil. Photosynthesis is computed using a light use efficiency model. Carbon assimilation by vegetation is coupled to the transpiration of water through stomatal conductance. PALADYN includes a dynamic vegetation module with five plant functional types competing for the grid cell share with their respective net primary productivity. PALADYN distinguishes between mineral soil carbon, peat carbon, buried carbon and shelf carbon. Each soil carbon type has its own soil carbon pools generally represented by a litter, a fast and a slow carbon pool in each soil layer. Carbon can be redistributed between the layers by vertical diffusion and advection. For the vegetated macro surface type, decomposition is a function of soil temperature and soil moisture. Carbon in permanently frozen layers is assigned a long turnover time which effectively locks carbon in permafrost. Carbon buried below ice sheets and on flooded ocean shelves is treated differently. The model also includes a dynamic peat module. PALADYN includes carbon isotopes 13C and 14C, which are tracked through all carbon pools. Isotopic discrimination is modelled only during photosynthesis. A simple methane module is implemented to represent methane emissions from anaerobic carbon decomposition in wetlands (including peatlands) and flooded ocean shelf. The model description is accompanied by a thorough model evaluation in offline mode for the present day and the historical period.
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27

Liston, Glen E., and Dorothy K. Hall. "An energy-balance model of lake-ice evolution." Journal of Glaciology 41, no. 138 (1995): 373–82. http://dx.doi.org/10.1017/s0022143000016245.

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AbstractA physically based mathematical model of the coupled lake, lake ice, snow and atmosphere system is developed for studying terrestrial-atmospheric interactions in high-elevation and high-latitude regions. The ability to model lake-ice freeze-up, break-up, total ice thickness and ice type offers the potential to describe the effects of climate change in these regions. Model output is validated against lake-ice observations made during the winter of 1992–93 in Glacier National Park, Montana. U.S.A. The model is driven with observed daily atmospheric forcing of precipitation, wind speed and air temperature. In addition to simulating complete energy-balance components over the annual cycle, model output includes ice freeze-up and break-up dates, and the end-of-season clear ice, snow-ice and total ice depths for two nearby lakes in Glacier National Park, each in a different topographic setting. Modeled ice features are found to agree closely with the lake-ice observations.Model simulations illustrate the key role that the wind component of the local climatic regime plays on the growth and decay of lake ice. The wind speed affects both the surface temperature and the accumulation of snow on the lake-ice surface. Higher snow accumulations on the lake ice depress the ice surface below the water line, causing the snow to become saturated and leading to the formation of snow-ice deposits. In regions having higher wind speeds, significantly less snow accumulates on the lake-ice surface, thus limiting snow-ice formation. The ice produced by these two different mechanisms has distinctly different optical and radiative properties, and affects the monitoring of frozen lakes using remote-sensing techniques.
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28

Liston, Glen E., and Dorothy K. Hall. "An energy-balance model of lake-ice evolution." Journal of Glaciology 41, no. 138 (1995): 373–82. http://dx.doi.org/10.3189/s0022143000016245.

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AbstractA physically based mathematical model of the coupled lake, lake ice, snow and atmosphere system is developed for studying terrestrial-atmospheric interactions in high-elevation and high-latitude regions. The ability to model lake-ice freeze-up, break-up, total ice thickness and ice type offers the potential to describe the effects of climate change in these regions. Model output is validated against lake-ice observations made during the winter of 1992–93 in Glacier National Park, Montana. U.S.A. The model is driven with observed daily atmospheric forcing of precipitation, wind speed and air temperature. In addition to simulating complete energy-balance components over the annual cycle, model output includes ice freeze-up and break-up dates, and the end-of-season clear ice, snow-ice and total ice depths for two nearby lakes in Glacier National Park, each in a different topographic setting. Modeled ice features are found to agree closely with the lake-ice observations.Model simulations illustrate the key role that the wind component of the local climatic regime plays on the growth and decay of lake ice. The wind speed affects both the surface temperature and the accumulation of snow on the lake-ice surface. Higher snow accumulations on the lake ice depress the ice surface below the water line, causing the snow to become saturated and leading to the formation of snow-ice deposits. In regions having higher wind speeds, significantly less snow accumulates on the lake-ice surface, thus limiting snow-ice formation. The ice produced by these two different mechanisms has distinctly different optical and radiative properties, and affects the monitoring of frozen lakes using remote-sensing techniques.
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29

Lockot, Gregori, Arne Ramisch, Bernd Wünnemann, Kai Hartmann, Torsten Haberzettl, Hao Chen, and Bernhard Diekmann. "A Process- and Provenance-Based Attempt to Unravel Inconsistent Radiocarbon Chronologies in Lake Sediments: An Example from Lake Heihai, North Tibetan Plateau (China)." Radiocarbon 57, no. 5 (2015): 1003–19. http://dx.doi.org/10.2458/azu_rc.57.18221.

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Aquatic macrophytes from a lacustrine environment are highly prone to a reservoir effect, resulting in an overestimation of age. This is often caused by the incorporation of dissolved carbon (CO2 and HCO3–) through photosynthesis from lake waters that have a different 14C activity than the atmosphere. The atmosphere-water disparity is often produced by a mixing of carbon between the water body and its terrestrial surroundings, a process highly prone to temporal variations. Thus, only a comprehensive understanding of the 14C budget over time enables a reliable chronology of lacustrine records. We studied lacustrine sediments from Lake Heihai on the northern Tibetan Plateau with a recent reservoir effect of 6465 ± 75 14C yr as estimated from accelerator mass spectrometry (AMS) dating of three living aquatic plants. Age inversions in a well-laminated composite core from the lake suggest that the reservoir effect markedly changed over the depositional period. In the lower part of the core, an excellent correlation was observed between the allochthonous input of dolomite and the inverse 14C ages, indicating the incorporation of dissolved 14C-dead carbon from a limestone catchment in the plant material. For the upper part of the core, sediment recycling of Holocene high-stand deposits may have further contributed to the reservoir effect. These findings give rise to a reliable process- and provenance-based chronology within a confidence interval supported by 137Cs measurements and magnetostratigraphic investigations. Our results highlight the need to identify the interactions of lakes with their surroundings to estimate reservoir-corrected ages in lacustrine settings.
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30

Durnford, D., V. Fortin, G. C. Smith, B. Archambault, D. Deacu, F. Dupont, S. Dyck, et al. "Toward an Operational Water Cycle Prediction System for the Great Lakes and St. Lawrence River." Bulletin of the American Meteorological Society 99, no. 3 (March 1, 2018): 521–46. http://dx.doi.org/10.1175/bams-d-16-0155.1.

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Abstract In this time of a changing climate, it is important to know whether lake levels will rise, potentially causing flooding, or river flows will dry up during abnormally dry weather. The Great Lakes region is the largest freshwater lake system in the world. Moreover, agriculture, industry, commerce, and shipping are active in this densely populated region. Environment and Climate Change Canada (ECCC) recently implemented the Water Cycle Prediction System (WCPS) over the Great Lakes and St. Lawrence River watershed (WCPS-GLS version 1.0) following a decade of research and development. WCPS, a network of linked models, simulates the complete water cycle, following water as it moves from the atmosphere to the surface, through the river network and into lakes, and back to the atmosphere. Information concerning the water cycle is passed between the models. WCPS is the first short-to-medium-range prediction system of the complete water cycle to be run on an operational basis anywhere. It currently produces two forecasts per day for the next three days. WCPS generally provides reliable results throughout the length of the forecast. The transmission of errors between the component models is reduced by data assimilation. Interactions between the environmental compartments are active. This ongoing intercommunication is valuable for extreme events such as rapid ice freeze-up and flooding or drought caused by abnormal amounts of precipitation. Products include precipitation; evaporation; lake water levels, temperatures, and currents; ice cover; and river flows. These products are of interest to a wide variety of governmental, commercial, and industrial groups, as well as the public.
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31

Huang, Wenfeng, Bin Cheng, Jinrong Zhang, Zheng Zhang, Timo Vihma, Zhijun Li, and Fujun Niu. "Modeling experiments on seasonal lake ice mass and energy balance in the Qinghai–Tibet Plateau: a case study." Hydrology and Earth System Sciences 23, no. 4 (April 30, 2019): 2173–86. http://dx.doi.org/10.5194/hess-23-2173-2019.

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Abstract. The lake-rich Qinghai–Tibet Plateau (QTP) has significant impacts on regional and global water cycles and monsoon systems through heat and water vapor exchange. The lake–atmosphere interactions have been quantified over open-water periods, yet little is known about the lake ice thermodynamics and heat and mass balance during the ice-covered season due to a lack of field data. In this study, a high-resolution thermodynamic ice model was applied in experiments of lake ice evolution and energy balance of a shallow lake in the QTP. Basal growth and melt dominated the seasonal evolution of lake ice, but surface sublimation was also crucial for ice loss, accounting for up to 40 % of the maximum ice thickness. Sublimation was also responsible for 41 % of the lake water loss during the ice-covered period. Simulation results matched the observations well with respect to ice mass balance components, ice thickness, and ice temperature. Strong solar radiation, negative air temperature, low air moisture, and prevailing strong winds were the major driving forces controlling the seasonal ice mass balance. The energy balance was estimated at the ice surface and bottom, and within the ice interior and under-ice water. Particularly, almost all heat fluxes showed significant diurnal variations including incoming, absorbed, and penetrated solar radiation, long-wave radiation, turbulent air–ice heat fluxes, and basal ice–water heat fluxes. The calculated ice surface temperature indicated that the atmospheric boundary layer stratification was consistently stable or neutral throughout the ice-covered period. The turbulent air–ice heat fluxes and the net heat gain by the lake were much lower than those during the open-water period.
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32

Zhang, Z. Q., G. P. Wang, X. G. Lv, H. J. Jia, and Q. H. Xu. "The sharp decline of East Asian summer monsoon at mid-Holocene indicated by the lake-wetland transition in the Sanjiang Plain, northeastern China." Climate of the Past Discussions 10, no. 6 (December 18, 2014): 4595–622. http://dx.doi.org/10.5194/cpd-10-4595-2014.

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Abstract. The timing of the waxing and wining of the East Asian summer monsoon during the Holocene is still under debate. In present study, we present the high-resolution grain-size and LOI records from a well-dated mud/peat profile to reveal the lake-wetland transition in the Sanjiang Plain and discuss its significance to Holocene monsoon evolutions. The results show that the shallow-water lakes have developed in low-lying areas of the plain before 4600 yr BP, corresponding to the Holocene monsoon maximum. Thereafter, the wetlands began to initiate with the extinction of the paleolakes, marking a lake-shrinking stage with the relative dry climate. Considering the prevalent monsoon climate in the Sanjiang Plain, we suggest the lake-wetland transition at 4600 yr BP indicate a sharp decline of the summer monsoon rather than the basin infilling process. Such a remarkable monsoon weakening event has been widely documented in northern China, and we associated it with the ocean–atmosphere interacting processes in low-latitude regions.
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33

Ma, Weiyao, Ling Bai, Weiqiang Ma, Wei Hu, Zhipeng Xie, Rongmingzhu Su, Binbin Wang, and Yaoming Ma. "Interannual and Monthly Variability of Typical Inland Lakes on the Tibetan Plateau Located in Three Different Climatic Zones." Remote Sensing 14, no. 19 (October 9, 2022): 5015. http://dx.doi.org/10.3390/rs14195015.

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Changes in lake water volume can reflect variations in regional hydrometeorology and are a sensitive indicator of regional environmental change. The Tibetan Plateau, referred to as the “Asian Water Tower”, has a large number of lakes. These lakes are in a natural state and are relatively unaffected by human activities. Understanding the changes to lake water volume is a key issue for the study of lake-atmosphere interactions and the effects of lake expansion and contraction on regional climate. By using multisource remote sensing and water level observations, this study systematically analyzed inter-annual changes from 1970 to 2021 of three typical inland lakes basin (Bamu Co-Peng Co basin, Langa Co-Mapum Yumco basin andLongmu Co-Songmuxi Co basin), which are located in different climatic regions of the Tibetan Plateau and monthly changes from 2019 to 2021 of Bamu Co, Langa Co and Longmu Co in the lake area, water level, and water volume. In addition, the study analyzed the response of lakes in different climate regions to climate change from 1979 to 2018. The main conclusions are as follows. (1) From 1970 to 2021, there were similar trends in lake changes between the primary and twin lakes. (2) The changes to lakes in different climatic regions are different: lakes in the monsoon-dominated region showed a significant trend of expansion from 2000 to 2014, but the trend slowed down and stabilized after 2014; lakes in the westerlies-dominated region showed a small expansion trend; lakes in the region affected by both westerlies and the monsoon showed an overall shrinking trend. (3) The monthly variation of lake water volume showed a trend of first increasing and then decreasing, with the largest relative change of lake water volume in August and September. (4) Precipitation is a dominant factor controlling lake variation during the year. (5) Temperature and precipitation are dominant meteorological elements affecting the decadal variation of the lake, and with the warming of the TP, temperature plays an increasingly important role.
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Wang, Binbin, Yaoming Ma, Yan Wang, Zhongbo Su, and Weiqiang Ma. "Significant differences exist in lake-atmosphere interactions and the evaporation rates of high-elevation small and large lakes." Journal of Hydrology 573 (June 2019): 220–34. http://dx.doi.org/10.1016/j.jhydrol.2019.03.066.

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35

Prior, Elizabeth M., Gretchen R. Miller, and Kelly Brumbelow. "Topographic and Landcover Influence on Lower Atmospheric Profiles Measured by Small Unoccupied Aerial Systems (sUAS)." Drones 5, no. 3 (August 26, 2021): 82. http://dx.doi.org/10.3390/drones5030082.

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Small unoccupied aerial systems (sUASs) are increasingly being used for field data collection and remote sensing purposes. Their ease of use, ability to carry sensors, low cost, and precise maneuverability and navigation make them a versatile tool for a field researcher. Procedures and instrumentation for sUASs are largely undefined, especially for atmospheric and hydrologic applications. The sUAS’s ability to collect atmospheric data for characterizing land–atmosphere interactions was examined at three distinct locations: Costa Rican rainforest, mountainous terrain in Georgia, USA, and land surfaces surrounding a lake in Florida, USA. This study aims to give further insight on rapid, sub-hourly changes in the planetary boundary layer and how land development alters land–atmosphere interactions. The methodology of using an sUAS for land–atmospheric remote sensing and data collection was developed and refined by considering sUAS wind downdraft influence and executing systematic flight patterns throughout the day. The sUAS was successful in gathering temperature and dew point data, including rapid variations due to changing weather conditions, at high spatial and temporal resolution over various land types, including water, forest, mountainous terrain, agriculture, and impermeable human-made surfaces. The procedure produced reliably consistent vertical profiles over small domains in space and time, validating the general approach. These findings suggest a healthy ability to diagnose land surface atmospheric interactions that influence the dynamic nature of the near-surface boundary layer.
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36

Wen, Ruilin, Jule Xiao, Zhigang Chang, Dayou Zhai, Qinghai Xu, Yuecong Li, Shigeru Itoh, and Zaur Lomtatidze. "Holocene climate changes in the mid-high-latitude-monsoon margin reflected by the pollen record from Hulun Lake, northeastern Inner Mongolia." Quaternary Research 73, no. 2 (March 2010): 293–303. http://dx.doi.org/10.1016/j.yqres.2009.10.006.

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Pollen-assemblage data from a sediment core from Hulun Lake in northeastern Inner Mongolia describe the changes in the vegetation and climate of the East Asian monsoon margin during the Holocene. Dry steppe dominated the lake basin from ca. 11,000 to 8000 cal yr BP, suggesting a warm and dry climate. Grasses and birch forests expanded 8000 to 6400 cal yr BP, implying a remarkable increase in the monsoon precipitation. From 6400 to 4400 cal yr BP, the climate became cooler and drier. Chenopodiaceae dominated the interval from 4400 to 3350 cal yr BP, marking extremely dry condition. Artemisia recovered 3350-2050 cal yr BP, denoting an amelioration of climatic conditions. Both temperature and precipitation decreased 2050 to 1000 cal yr BP as indicated by decreased Artemisia and the development of pine forests. During the last 1000 yr, human activities might have had a significant influence on the environment of the lake region. We suggest that the East Asian summer monsoon did not become intensified until 8000 cal yr BP due to the existence of remnant ice sheets in the Northern Hemisphere. Changes in the monsoon precipitation on millennial to centennial scales would be related to ocean-atmosphere interactions in the tropical Pacific.
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37

Gerken, T., W. Babel, M. Herzog, K. Fuchs, F. Sun, Y. Ma, T. Foken, and H. F. Graf. "High-resolution modelling of interactions between soil moisture and convection development in mountain enclosed Tibetan basin." Hydrology and Earth System Sciences Discussions 12, no. 5 (May 4, 2015): 4631–75. http://dx.doi.org/10.5194/hessd-12-4631-2015.

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Abstract. The Tibetan Plateau plays a significant role in the atmospheric circulation and the Asian monsoon system. Turbulent surface fluxes and the evolution of boundary layer clouds to deep and moist convection provide a feedback system that modifies the Plateau's surface energy balance on scales that are currently unresolved in mesoscale models. This work analyses the land surface's role and specifically the influence of soil moisture on the triggering of convection at a cross-section of the Nam Co Lake basin, 150 km north of Lhasa using a cloud resolving atmospheric model with a fully coupled surface. The modelled turbulent fluxes and development of convection compare reasonably well with the observed weather. The simulations span Bowen-ratios of 0.5 to 2.5. It is found that convection development is strongest at intermediate soil moistures. Dry cases with soils close to the permanent wilting point are moisture limited in the convection development, while convection in wet soil moisture cases is limited by cloud cover reducing incoming solar radiation and sensible heat fluxes. This has a strong impact on the surface energy balance. This study also shows that local development of convection is an important mechanism for the upward transport of water vapour that originates from the lake basin that can then be transported to dryer regions of the plateau. Both processes demonstrate the importance of soil moisture and surface–atmosphere interactions on the energy and hydrological cycles of the Tibetan Plateau.
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38

Gerken, T., W. Babel, M. Herzog, K. Fuchs, F. Sun, Y. Ma, T. Foken, and H. F. Graf. "High-resolution modelling of interactions between soil moisture and convective development in a mountain enclosed Tibetan Basin." Hydrology and Earth System Sciences 19, no. 9 (September 29, 2015): 4023–40. http://dx.doi.org/10.5194/hess-19-4023-2015.

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Abstract. The Tibetan Plateau plays a significant role in atmospheric circulation and the Asian monsoon system. Turbulent surface fluxes and the evolution of boundary-layer clouds to deep and moist convection provide a feedback system that modifies the plateau's surface energy balance on scales that are currently unresolved in mesoscale models. This work analyses the land surface's role and specifically the influence of soil moisture on the triggering of convection at a cross section of the Nam Co Lake basin, 150 km north of Lhasa using a cloud-resolving atmospheric model with a fully coupled surface. The modelled turbulent fluxes and development of convection compare reasonably well with the observed weather. The simulations span Bowen ratios of 0.5 to 2.5. It is found that convective development is the strongest at intermediate soil moisture. Dry cases with soils close to the permanent wilting point are moisture limited in convective development, while convection in wet soil moisture cases is limited by cloud cover reducing incoming solar radiation and sensible heat fluxes, which has a strong impact on the surface energy balance. This study also shows that local development of convection is an important mechanism for the upward transport of water vapour, which originates from the lake basin that can then be transported to dryer regions of the plateau. Both processes demonstrate the importance of soil moisture and surface–atmosphere interactions on the energy and hydrological cycles of the Tibetan Plateau.
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39

Grenfell, Thomas C., Donald K. Perovich, Hajo Eicken, Bonnie Light, Jeremy Harbeck, Thomas H. George, and Andrew Mahoney. "Energy- and mass-balance observations of the land–ice–ocean–atmosphere system near Barrow, Alaska, USA, November 1999–July 2002." Annals of Glaciology 44 (2006): 193–99. http://dx.doi.org/10.3189/172756406781811222.

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AbstractWe present results from a comprehensive field study carried out near Barrow, Alaska, USA, designed to characterize local- to intermediate-scale sea-ice processes in the Arctic coastal zone of central importance to the annual cycle and evolution of the coastal sea ice. Included in this are the behavior of the snow cover of the ice and adjacent tundra and lake system; concurrent studies of mass balance of the sea ice and lake ice; interaction of shortwave radiation with the shore-fast ice and the adjacent land surfaces; evolution of the area coverage and distribution of the various surface types; and the resulting regional albedo values. Maximum snow depths decreased during 2000–02 from 0.38 m to 0.26 m. Ice-melt rates in 2001 were 0.05 and 0.028md–1 at the top and bottom of the sea ice respectively, two to three times larger than observations from the central Arctic. Detailed surface results combined with aircraft photography were used to calculate regional albedos for the late spring and early summer of 2001. Values ranged from 0.8 for all cold snow-covered surfaces to approximately 0.4 for melting sea ice and lake ice vs 0.18 for bare tundra. Regional and surface-based values of cumulative shortwave radiation entering the ice were consistent, indicating that albedo sampling on a scale of 200m can provide a useful representation for regional sea-ice albedo.
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40

Newby, Paige E., Bryan N. Shuman, Jeffrey P. Donnelly, and Dana MacDonald. "Repeated century-scale droughts over the past 13,000 yr near the Hudson River watershed, USA." Quaternary Research 75, no. 3 (May 2011): 523–30. http://dx.doi.org/10.1016/j.yqres.2011.01.006.

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AbstractLong-term sediment and ground-penetrating radar data from Davis Pond, a small lake near the Hudson River valley, reveal past droughts in a historically humid region that presently supplies water to millions of people in and around New York City. A minimum of eleven sandy paleoshoreline deposits in the lake date from 13.4 to 0.6 cal ka BP. The deposits span 1500 to 200 yr between bracketing radiocarbon ages, and intrude into lacustrine silts up to 9.0 m below the modern lake surface in a transect of six sediment cores. Three low stands, ca. 13.4–10.9, 9.2 and 8.2 cal ka BP indicate low regional moisture balance when low temperatures affected the North Atlantic region. Consistent with insolation trends, water levels rose from ca. 8.0 cal ka BP to present, but five low stands interrupted the rise and are likely associated with ocean–atmosphere interactions. Similar to evidence from other studies, the data from Davis Pond indicate repeated multi-century periods of prolonged or frequent droughts super-imposed on long-term regional trends toward high water levels. The patterns indicate that water supplies in this heavily populated region have continuously varied at multiple time scales and confirm that humid regions such as the northeastern United States are more prone to severe drought than historically expected.
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41

Mercier, F. "Interannual lake level fluctuations (1993–1999) in Africa from Topex/Poseidon: connections with ocean–atmosphere interactions over the Indian Ocean." Global and Planetary Change 32, no. 2-3 (April 15, 2002): 141–63. http://dx.doi.org/10.1016/s0921-8181(01)00139-4.

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42

Zhao, Chen, Pu Zhang, Xiangzhong Li, Youfeng Ning, Liangcheng Tan, R. Lawrence Edwards, Xiunan Yao, and Hai Cheng. "Distribution Characteristics and Influencing Factors of Uranium Isotopes in Saline Lake Waters in the Northeast of Qaidam Basin." Minerals 10, no. 1 (January 17, 2020): 74. http://dx.doi.org/10.3390/min10010074.

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Four saline lakes in the northeast of Qaidam Basin were selected to explore the distribution characteristics and influencing factors of uranium isotopes in lake waters with high evaporation background. The 238U concentration and the activity ratios of 234U/238U ([234U/238U]AR) showed that there was no significant change in the same lake, but there was a certain degree of difference in the distribution between different lakes. We found that aqueous 238U concentration within a certain range increased with an increase in TDS (total dissolved solid) and salinity, as was also the case with pH. As in natural waters, the pH affects the speciation of 238U, but TDS and salinity affect the adsorption process of aqueous 238U. Further, the replenishment of water will also affect the uranium isotope concentration for lakes, but it is not the main influencing factor for saline lakes. Therefore, we suggest that pH is the dominant factor affecting changes in aqueous 238U concentration of the sampled saline lakes. The [234U/238U]AR in these saline lakes are closely related to the input water and the associated water–rock interactions involving sediments, atmosphere dust, and organic material, etc. during the evolution stage, metamorphous degree, and hydrochemistry of the saline lakes. Lake water samples collected in the maximum and minimum discharge water period, were used to evaluate the seasonal distribution characteristics of aqueous 238U, and we found that 238U concentration did not show an evident change with the seasons in these saline lakes. If the 238U concentration and [234U/238U]AR can remain consistent during a period of time, then the sediment ages and/or sedimentation rates could be determined by lake sediment and/or biogenic carbonate in future, thus allowing for the accurate reconstruction of the paleoclimate and paleoenvironment.
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43

Dhar, Amalesh, Valerie S. Miller, Sarah R. Wilkinson, and M. Anne Naeth. "Substrate and Topsoil Impact on Soil Water and Soil Temperature in Arctic Diamond Mine Reclamation." Soil Systems 6, no. 1 (January 19, 2022): 12. http://dx.doi.org/10.3390/soilsystems6010012.

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Soil properties in the Arctic are insufficiently explored and documented, particularly extensive monitoring of soil water and soil temperature over a period of time. Soil water and soil temperature are critical for understanding land surface and atmosphere interactions and are considered key factors for revegetation during mine reclamation. This study assessed how substrate and topsoil influenced soil temperature and soil water content at a reclaimed diamond mine in the Northwest Territories of Canada. Three substrates (crushed rock, processed kimberlite, and lake sediment) with and without topsoil were used. Mean air temperature changed little from year to year, although summer temperature showed a slightly increasing trend. Both annual and summer precipitation sharply declined over time. Soil water was influenced more by substrate than by placing 10 cm of topsoil on it. Processed kimberlite had greater water retention characteristics and water content than lake sediment and crushed rock substrates (significantly). Surface soil water content was lower with than without topsoil, suggesting that 10 cm of topsoil was not enough to influence it. Soil temperatures were not influenced by either substrate or topsoil. This study suggests processed kimberlite could be used as a substrate component for water and temperature management during reclamation of this extreme environment.
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44

Yao, Tandong, Yongkang Xue, Deliang Chen, Fahu Chen, Lonnie Thompson, Peng Cui, Toshio Koike, et al. "Recent Third Pole’s Rapid Warming Accompanies Cryospheric Melt and Water Cycle Intensification and Interactions between Monsoon and Environment: Multidisciplinary Approach with Observations, Modeling, and Analysis." Bulletin of the American Meteorological Society 100, no. 3 (March 2019): 423–44. http://dx.doi.org/10.1175/bams-d-17-0057.1.

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AbstractThe Third Pole (TP) is experiencing rapid warming and is currently in its warmest period in the past 2,000 years. This paper reviews the latest development in multidisciplinary TP research associated with this warming. The rapid warming facilitates intense and broad glacier melt over most of the TP, although some glaciers in the northwest are advancing. By heating the atmosphere and reducing snow/ice albedo, aerosols also contribute to the glaciers melting. Glacier melt is accompanied by lake expansion and intensification of the water cycle over the TP. Precipitation has increased over the eastern and northwestern TP. Meanwhile, the TP is greening and most regions are experiencing advancing phenological trends, although over the southwest there is a spring phenological delay mainly in response to the recent decline in spring precipitation. Atmospheric and terrestrial thermal and dynamical processes over the TP affect the Asian monsoon at different scales. Recent evidence indicates substantial roles that mesoscale convective systems play in the TP’s precipitation as well as an association between soil moisture anomalies in the TP and the Indian monsoon. Moreover, an increase in geohazard events has been associated with recent environmental changes, some of which have had catastrophic consequences caused by glacial lake outbursts and landslides. Active debris flows are growing in both frequency of occurrences and spatial scale. Meanwhile, new types of disasters, such as the twin ice avalanches in Ali in 2016, are now appearing in the region. Adaptation and mitigation measures should be taken to help societies’ preparation for future environmental challenges. Some key issues for future TP studies are also discussed.
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45

Anslan, Sten, Mina Azizi Rad, Johannes Buckel, Paula Echeverria Galindo, Jinlei Kai, Wengang Kang, Laura Keys, et al. "Reviews and syntheses: How do abiotic and biotic processes respond to climatic variations in the Nam Co catchment (Tibetan Plateau)?" Biogeosciences 17, no. 5 (March 6, 2020): 1261–79. http://dx.doi.org/10.5194/bg-17-1261-2020.

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Abstract. The Tibetan Plateau (TP) is the largest alpine plateau on Earth and plays an important role in global climate dynamics. On the TP, climate change is happening particularly fast, with an increase in air temperature twice the global average. The particular sensitivity of this high mountain environment allows observation and tracking of abiotic and biotic feedback mechanisms. Closed lake systems, such as Nam Co on the central TP, represent important natural laboratories for tracking past and recent climatic changes, as well as geobiological processes and interactions within their respective catchments. This review gives an interdisciplinary overview of past and modern environmental changes using Nam Co as a case study. In the catchment area, ongoing rise in air temperature forces glaciers to melt, contributing to a rise in lake level and changes in water chemistry. Some studies base their conclusions on inconsistent glacier inventories, but an ever-increasing deglaciation and thus higher water availability have persisted over the last few decades. Increasing water availability causes translocation of sediments, nutrients and dissolved organic matter to the lake, as well as higher carbon emissions to the atmosphere. The intensity of grazing has an additional and significant effect on CO2 fluxes, with moderate grazing enhancing belowground allocation of carbon while adversely affecting the C sink potential through reduction of above-surface and subsurface biomass at higher grazing intensities. Furthermore, increasing pressure from human activities and livestock grazing are enhancing grassland degradation processes, thus shaping biodiversity patterns in the lake and catchment. The environmental signal provided by taxon-specific analysis (e.g., diatoms and ostracods) in Nam Co revealed profound climatic fluctuations between warmer–cooler and wetter–drier periods since the late Pleistocene and an increasing input of freshwater and nutrients from the catchment in recent years. Based on the reviewed literature, we outline perspectives to further understand the effects of global warming on geodiversity and biodiversity and their interplay at Nam Co, which acts as a case study for potentially TP-level or even worldwide processes that are currently shaping high mountain areas.
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46

Li, Jialin, Xinting Yu, Ella Sciamma-O’Brien, Chao He, Joshua A. Sebree, Farid Salama, Sarah M. Hörst, and Xi Zhang. "A Cross-laboratory Comparison Study of Titan Haze Analogs: Surface Energy." Planetary Science Journal 3, no. 1 (January 1, 2022): 2. http://dx.doi.org/10.3847/psj/ac3d27.

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Abstract In Titan’s nitrogen-methane atmosphere, photochemistry leads to the production of complex organic particles, forming Titan’s thick haze layers. Laboratory-produced aerosol analogs, or “tholins,” are produced in a number of laboratories; however, most previous studies have investigated analogs produced by only one laboratory rather than a systematic, comparative analysis. In this study, we performed a comparative study of an important material property, the surface energy, of seven tholin samples produced in three independent laboratories under a broad range of experimental conditions, and we explored their commonalities and differences. All seven tholin samples are found to have high surface energies and are therefore highly cohesive. Thus, if the surface sediments on Titan are similar to tholins, future missions such as Dragonfly will likely encounter sticky sediments. We also identified a commonality between all the tholin samples: a high dispersive (nonpolar) surface energy component of at least 30 mJ m−2. This common property could be shared by the actual haze particles on Titan as well. Given that the most abundant species interacting with the haze on Titan (methane, ethane, and nitrogen) are nonpolar in nature, the dispersive surface energy component of the haze particles could be a determinant factor in condensate−haze and haze−lake liquid interactions on Titan. With this common trait of tholin samples, we confirmed the findings of a previous study by Yu et al. that haze particles are likely good cloud condensation nuclei for methane and ethane clouds and would likely be completely wetted by the hydrocarbon lakes on Titan.
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47

Goyette, Stéphane. "Numerical investigation with a coupled single-column lake-atmosphere model: using the Alpert–Stein factor separation methodology to assess the sensitivity of surface interactions." Climate Dynamics 48, no. 7-8 (June 3, 2016): 2359–73. http://dx.doi.org/10.1007/s00382-016-3209-1.

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48

Whiteman, C. David, and Shiyuan Zhong. "Downslope Flows on a Low-Angle Slope and Their Interactions with Valley Inversions. Part I: Observations." Journal of Applied Meteorology and Climatology 47, no. 7 (July 1, 2008): 2023–38. http://dx.doi.org/10.1175/2007jamc1669.1.

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Abstract Thermally driven downslope flows were investigated on a low-angle (1.6°) slope on the west side of the floor of Utah’s Salt Lake Valley below the Oquirrh Mountains using data from a line of four tethered balloons running down the topographic gradient and separated by about 1 km. The study focused on the evolution of the temperature and wind structure within and above the slope flow layer and its variation with downslope distance. In a typical situation, on clear, undisturbed October nights a 25-m-deep temperature deficit of 7°C and a 100–150-m-deep downslope flow with a jet maximum speed of 5–6 m s−1 at 10–15 m AGL developed over the slope during the first 2 h following sunset. The jet maximum speed and the downslope volume flux increased with downslope distance. The downslope flows weakened in the late evening as the stronger down-valley flows expanded to take up more of the valley atmosphere and as ambient stability increased in the lower valley with the buildup of a nocturnal temperature inversion. Downslope flows over this low-angle slope were deeper and stronger than has been reported previously by other investigators, who generally investigated steeper slopes and, in many cases, slopes on the sidewalls of isolated mountains where the downslope flows are not subject to the influence of nighttime buildup of ambient stability within valleys.
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49

Li, Guangwei, Xianhong Meng, Eleanor Blyth, Hao Chen, Lele Shu, Zhaoguo Li, Lin Zhao, and Yingsai Ma. "Impact of Fully Coupled Hydrology-Atmosphere Processes on Atmosphere Conditions: Investigating the Performance of the WRF-Hydro Model in the Three River Source Region on the Tibetan Plateau, China." Water 13, no. 23 (December 2, 2021): 3409. http://dx.doi.org/10.3390/w13233409.

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The newly developed WRF-Hydro model is a fully coupled atmospheric and hydrological processes model suitable for studying the intertwined atmospheric hydrological processes. This study utilizes the WRF-Hydro system on the Three-River source region. The Nash-Sutcliffe efficiency for the runoff simulation is 0.55 compared against the observed daily discharge amount of three stations. The coupled WRF-Hydro simulations are better than WRF in terms of six ground meteorological elements and turbulent heat flux, compared to the data from 14 meteorological stations located in the plateau residential area and two flux stations located around the lake. Although WRF-Hydro overestimates soil moisture, higher anomaly correlation coefficient scores (0.955 versus 0.941) were achieved. The time series of the basin average demonstrates that the hydrological module of WRF-hydro functions during the unfrozen period. The rainfall intensity and frequency simulated by WRF-Hydro are closer to global precipitation mission (GPM) data, attributed to higher convective available potential energy (CAPE) simulated by WRF-Hydro. The results emphasized the necessity of a fully coupled atmospheric-hydrological model when investigating land-atmosphere interactions on a complex topography and hydrology region.
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Chu, Guoqiang, Qing Sun, Xiaohua Wang, Meimei Liu, Yuan Lin, Manman Xie, Wenyu Shang, and Jiaqi Liu. "Seasonal temperature variability during the past 1600 years recorded in historical documents and varved lake sediment profiles from northeastern China." Holocene 22, no. 7 (December 29, 2011): 785–92. http://dx.doi.org/10.1177/0959683611430413.

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Seasonal temperature variability over longer timescales could offer new insights into understanding different forcing factors and response processes in the climate system. Here we report an alkenone-based temperature reconstruction for growing season over the past 1600 years from the varved sediment in Lake Sihailongwan, northeastern China. The most notable cold spells occurred during the periods ad 480–860, ad 1260–1300, ad 1510–1570 and ad 1800–1900 with a temperature decrease of about 1°C compared with the 20th century. Based on the historical evidence such as ‘snow or frost in the summertime’ and ‘no ice during the wintertime’, we compile extreme cold summer events and warm winter events over the past 1600 years. The ‘Little Ice Age’ time period experienced more extreme cold summer/warm winter events, while the ‘Medieval Warm Period’ had milder winters. Comparatively, the natural proxy data show a general similar pattern with historical documents at decadal time scales, except for between ad 1620 and 1720. Our results show multidecadal to centennial variations in seasonal temperature, possibly caused by interactions of external natural forcing and atmosphere–ocean circulations.
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