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141.
Disturbance of light-absorbing aerosols on the albedo in a winter snowpack of Central Tibet 总被引:1,自引:0,他引:1
A field observation on the albedo of the snowpack in Central Tibet was conducted in the Nam Co region in the winter of 2011. Snow properties, including grain size and density, were measured in the field, and surface-layer snow samples (down to 5 cm) were collected. The average concentrations of black carbon and dust were 72 ppbm (close to that in the glaciers of Mt. Nyainqentanglha) and 120 ppmm, respectively. Inverse trends were found to exist between the albedo of the snowpack and light-absorbing aerosols (LAAs) as well as grain size growth. Modeling showed that black carbon, dust, and grain growth in the winter snowpack can reduce the broadband albedo by 11%, 28%, and 61%, respectively. 相似文献
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利用河西走廊东部5个气象站1961─2007年逐月积雪深度、积雪日数和沙尘天气的常规观测资料,分析了河西走廊东部冬春季积雪深度、积雪日数和春夏季沙尘日数的时空变化特征,进而探讨河西走廊东部冬春季积雪与春夏季沙尘天气的关系. 结果表明:受海拔高度、地理位置以及天气系统等影响,河西走廊东部积雪从东南向西北递减,高海拔地区的积雪多于低海拔地区;沙尘日数从西北向东南递减,低海拔地区的沙尘日数明显多于高海拔地区. 河西走廊东部冬春季积雪与春夏季沙尘日数呈显著负相关. 积雪深度与沙尘日数的负相关性高于积雪日数与沙尘日数的负相关性;冬春季积雪对春季沙尘的影响大于对夏季沙尘的影响;山区积雪与沙尘日数的相关性高于平原区积雪与沙尘日数的相关性. 相似文献
144.
Sean W. Fleming Lucas Zukiewicz Michael L. Strobel Heather Hofman Angus G. Goodbody 《Journal of the American Water Resources Association》2023,59(4):585-599
The Snow Survey and Water Supply Forecasting (SSWSF) Program and the Soil Climate Analysis Network (SCAN) of the United States Department of Agriculture's Natural Resources Conservation Service (NRCS) generate key observational and predictive information for water managers. Examples include mountain climate and snow monitoring through manual snow surveys and the SNOw TELemetry (SNOTEL) and SNOtel LITE networks, in situ soil moisture data acquisition through the SCAN and SNOTEL networks, and water supply forecasting using river runoff prediction models. The SSWSF Program has advanced continuously over the decades and is a major source of valuable water management information across the western United States, and the SCAN network supports agricultural and other water users nationwide. Product users and their management goals are diverse, and use-cases range from guiding crop selection to seasonal flood risk assessment, drought monitoring and prediction, avalanche and fire prediction, hydropower optimization, tracking climate variability and change, environmental management, satisfying international treaty and domestic legal requirements, and more. Priorities going forward are to continue innovating to enhance the accuracy and completeness of the observational and model-generated data products these programs deliver, including expanded synergies with the remote sensing community and uptake of artificial intelligence while maintaining long-term operational reliability and consistency at scale. 相似文献
145.
本文对2018年12月至2019年3月东北地区86个积雪样品的阴阳离子进行测定,运用MODIS、相关性分析、后向轨迹等方法研究积雪中阴阳离子的空间分布特征及来源。结果表明:积雪中离子平均浓度大小为Ca2+>SO42->CL->NO2->NO3->Na+>K+>Mg2+>NH4+>F-,其中SO42-和Ca2+是主要的阴、阳离子,分别占总离子浓度的29.54%和30.97%。积雪的pH平均值为6.57,呈微酸性,且电导率与Ca2+、SO42-、Mg2+、CL-... 相似文献
146.
采用超高效液相色谱-质谱联用仪(UPLC-MS-MS)测定了某城区雪水中12种有机磷酸酯(OPEs)。结果表明:12种OPEs在所有采样点均有检出,总浓度范围为118.24~1 580.26 ng/L,平均浓度为899.77 ng/L。烷基磷酸酯是检出的主要污染物,磷酸三(1-氯-2-丙基)酯(TCPP)和磷酸三丁氧乙酯(TBEP)是最主要的单体OPEs,分别占ΣOPEs的20.31%~63.52%和3.51%~62.10%。ΣOPEs的浓度水平与人类生产生活活动量密切相关,在科研单位1号和科研单位2号的实验室,以及火车站1号和火车站2号附近ΣOPEs的浓度较高,公园1号和公园2号的浓度较低。对雪水中OPEs进行源解析,发现建材涂料、塑料橡胶制品、交通运输、家居装潢和电子产品可能是该城区雪水中OPEs的主要来源。根据计算得到的雪水中OPEs的健康风险均低于理论风险阈值来看,研究区域雪水中OPEs的生态风险总体处于低水平,但是部分采样点雪水中2-乙基己基二苯基磷酸酯(EDHPP)具有中等生态风险。 相似文献
147.
The presence of well-known atmospheric pollutants is regularly screened for in large towns but knowledge about the effects of mixtures of different pollutants and especially their genotoxic potential is largely missing. Since falling snow collects pollutants from the air, melted snow samples could be suitable for evaluating potential genotoxicity. For this purpose the Allium cepa anaphase–telophase test was used to analyse melted snow samples from Belgrade, the capital city of Serbia. Samples of snow were taken at two sites, characterized by differences in pollution intensity, in three successive years. At the more polluted site the analyses showed a very high degree of both toxicity and genotoxicity in the first year of the study corresponding to the effects of the known mutagen used as the positive control. At the other site the situation was much better but not without warning signals. The results showed that standard analyses for the presence of certain contaminants in the air do not give an accurate picture of the possible consequences of urban air pollution because the genotoxic potential remains hidden. The A. cepa test has been demonstrated to be very convenient for evaluation of air pollution through analyses of melted snow samples. 相似文献
148.
149.
Daniel R. Fuka Zachary M. Easton Erin S. Brooks Jan Boll Tammo S. Steenhuis M. Todd Walter 《Journal of the American Water Resources Association》2012,48(6):1151-1161
Abstract: We present a method to integrate a process‐based (PB) snowmelt model that requires only daily temperature and elevation information into the Soil and Water Assessment Tool (SWAT) model. The model predicts the spatiotemporal snowpack distribution without adding additional complexity, and in fact reduces the number of calibrated parameters. To demonstrate the utility of the PB model, we calibrate the PB and temperature‐index (TI) SWAT models to optimize agreement with stream discharge on a 46‐km2 watershed in northwestern Idaho, United States, for 10 individual years and use the calibrated parameters for the year with the best agreement to run the model for 15 remaining years. Stream discharge predictions by the PB and TI model were similar, although the PB model simulated snowmelt more accurately than the TI model for the remaining 15‐year period. Spatial snow distributions predicted by the PB model better matched observations from LandSat imagery and a SNOTEL station. Results for this watershed show that including PB snowmelt in watershed models is feasible, and calibration of TI‐based watershed models against discharge can incorrectly predict snow cover. 相似文献
150.