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黑河流域生态—水文过程综合遥感观测联合试验总体设计 总被引：17，自引：4，他引：13
介绍了"黑河流域生态—水文过程综合遥感观测联合试验"的背景、科学目标、试验组成和试验方案。试验的总体目标是显著提升对流域生态和水文过程的观测能力,建立国际领先的流域观测系统,提高遥感在流域生态—水文集成研究和水资源管理中的应用能力。由基础试验、专题试验、应用试验、产品与方法研究和信息系统组成。其中,①基础试验:搭载微波辐射计、成像光谱仪、热像仪、激光雷达等航空遥感设备,开展一系列关键生态和水文参量的观测;发展遥感正向模型及反演和估算方法。形成覆盖全流域的水文气象综合观测网,为流域生态—水文模型研究提供更有代表性的模型参数、驱动数据及更高精度的验证数据。构建无线传感器网络,度量生态水文模型所需的若干关键的驱动、参数和模型状态的空间异质性。开展航空遥感定标和地基遥感试验。依托传感器网络,并辅之以地面同步和加密观测,开展遥感产品真实性检验。②专题试验:开展"非均匀下垫面多尺度地表蒸散发观测试验",采用密集的涡动相关仪、大孔径闪烁仪与自动气象站的观测矩阵,为揭示地表蒸散发的空间异质性,实现非均匀下垫面地表蒸散发的尺度扩展,发展和验证蒸散发模型提供基础数据。③应用试验:在流域上、中、下游分别开展针对积雪和冻土水文、灌溉水平衡和作物生长、生态耗水的综合观测试验,将观测数据和遥感产品用于上游分布式水文模型、中游地表水—地下水—农作物生长耦合模型、下游生态耗水模型,通过实证研究提升遥感在流域生态—水文集成研究和水资源管理中的应用能力。加强试验将在2012年5月起按中游、上游、下游的顺序展开,全流域持续观测期为2013—2015年。在各类试验的支持下,开展全流域生态—水文关键参量遥感产品生产,发展尺度转换方法,建立多源遥感数据同化系统。 相似文献
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奚玉英 《成都信息工程学院学报》1988,(1)
雅砻江、金沙江、澜沧江、怒江(以下简称“四江”)发源于青藏高原东南部,流经横断山区和云贵高原,总集水面积约77.2万km~2。域内地形复杂,高差悬殊,其水文气候特性在三度空间具有明显的差异。 本文宏观分析了“四江”流域水文气候特性及其与地形、地势的关系,认为复杂的地形和高亢的地势是形成“四江”流域特殊水文气候条件的重要因素。 相似文献
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Michael H. Cosh Jery R. Stedinger Steve C. Ou Kuo-Nan Liou Wilfried Brutsaert 《Advances in water resources》2007
This study focuses on how the variability of land surface temperature and vegetation density at the SGP ARM-CART site changes over episodic (day to day) and seasonal time scales using AVHRR satellite data. Four drying periods throughout the year are analyzed. Land surface temperature had an erratic relationship with time exhibiting no deterministic pattern from day-to-day or season-to-season. Furthermore, it did not exhibit spatial pattern persistence. On the other hand, vegetation density had a consistent spatial pattern and temporal decay during average length drying periods (less than 7 days) as well as within a season. However, there were distinct differences in the seasonal pattern of variation between winter and growing seasons. In addition, the paper highlights a methodology to quantify the relationships that exist at the land surface between the primary parameter of interest and the controlling variables. 相似文献
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流域面雨量估算技术综述 总被引：15，自引：3，他引：15
面雨量是水文气象中一个重要参量。面雨量的估算直接关系到洪水预报精度和洪水调度决策的科学性。由于降水空间分布的复杂性,如何准确估算流域面雨量一直是个科学难题。传统方法根据常规降水观测,应用空间分析技术来估算面雨量。随着非常规观测技术的发展,以雷达、卫星估测降水资料为主并结合自动气象站降水观测资料,通过资料融合来进行估算已成为流域面雨量估算技术的发展趋势。而以GIS为平台,实现数据分析和显示一体化管理则代表了面雨量业务系统的发展方向。通过水文模拟与水文观测的比较,可以对面雨量估算结果进行间接检验。 相似文献
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气候系统中的水循环处于不断运转演化和更新中。近年来在全球变暖和人类活动的双重影响下,水文循环发生了显著变化,引起了社会和学界的广泛关注。水文循环是气候系统的核心,是连接气候子系统的纽带,也是水文气象学研究的核心问题。近年来国内外学者采用各种观测手段及海-陆-气耦合模型检测和模拟水文循环变化,取得了丰硕成果。对其变化的物理机制和驱动因素有了深入的理解,提高了对其未来可能变化的预测预估水平。文中对最近20余年与水文气象学相关的水文循环发生的变化,引起全球、区域及流域水文循环通量变化的原因,以及未来变化的预测等问题所取得的进展做了较全面的阐述。最后对水文气象学领域水文循环变化研究应关注的问题进行了探讨。 相似文献
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Marc Muselli Daniel Beysens Jacques Marcillat Irina Milimouk Torbjrn Nilsson Alain Louche 《Atmospheric Research》2002,64(1-4)
We report on the development of an inexpensive radiative condenser for collecting atmospheric vapor. Based on the experience gained using a small working model in Grenoble (France), a prototype of 10×3 m2 was established in Ajaccio (Corsica, France). The condensing surface is a rectangular foil made of TiO2 and BaSO4 microspheres embedded in polyethylene and has an angle of 30° with respect to horizontal. The hollow part of the device, thermally isolated, faces the direction of the dominant nocturnal wind. Dew measurements were correlated with meteorological data and compared to dew condensed on a horizontal polymethylmethacrylate (PMMA, Plexiglas) reference plate. The plate served as a reference standard unit and was located nearby. Between July 22, 2000 and November 11, 2001 (478 days), there were 145 dew days for the reference plate (30%), but 214 dew days for the condenser (45%). This yield corresponds to 767 l (3.6 l, on average, per dew day). The maximum yield in the period was 11.4 l/day. Dew mass can be fitted to a simple model that predicts dew production from simple meteorological data (temperature, humidity, wind velocity, cloud cover). Chemical analyses of the water collected from the plate were performed from October 16, 1999 to July 16, 2000 and from the condenser, from July 17, 2000 to March 17, 2001. The following parameters were investigated: suspended solids, pH, concentration of SO42−, Cl−, K+, Ca2+ ions. Only Cl− and SO42− ions were sometimes found significant. Wind direction analyses revealed that Cl− is due to the sea spray and SO42− to the combustion of fuel by an electrical plant located in the Ajaccio Gulf. Except for a weak acidity (average pH≈6) and high concentration of suspended solids, dew water fits the requirements for potable water in France with reference to the above ions. 相似文献
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Hydrometeorological Aspects of Floods in India 总被引：1，自引：1，他引：1
The Indian sub-continent being located in the heart of the summermonsoon belt, receives in most parts more than 75% of its annual rainfall during the fourmonsoon months of June to September. As the bulk of summer monsoon rainfall occurs withina period of four months, naturally majority of floods occur in Indian rivers during thisseason only. The ground conditions also help in generating high percentage of run-offbecause of the antecedent wet conditions caused by rainy spells occurring within the monsoonperiod itself. Besides mentioning different weather systems, which cause heavy rainfall and consequentfloods, a detailed discussion of 15 years' floods in different river systems has alsobeen given in the article. This study has shown that the flood problem in India is mostly confinedto the states located in the Indo-Gangetic plains, northeast India and occasionally in therivers of Central India. 相似文献
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