中国北方不同气候区晴天陆面过程区域特征差异

采用2008年7～9月份观测的中国干旱-半干旱区实验观测协同与集成研究资料,将我国北方干旱一半干旱区根据气候类型和地理位置划分为西北干旱区、黄土高原区和东北冷区三个区域,分析了干旱-半干旱区陆面热量平衡和辐射平衡日变化的区域差异.结果显示:不同气候区域的地表辐射和能量过程差异明显,而这种差异主要源于大气和土壤中可利用水...

Regional Differences in the Characteristics of Clear-Sky Land Surface Processes H38in Distinct Climatic Zones over Northern China

By dividing the semi-arid and arid regions into three parts: arid region in the northwest, Loess Plateau, and cold region in the northeast, the regional differences in the diurnal variation of land surface radiation and energy processes in the semi-arid and arid regions are investigated using the data measured during July and September, 2008, provided by the Experimental Co-observation and Integral Research in the Semi-arid and Arid Regions over northern China. The results show that pronounced regional differences in land surface radiation and energy processes are seen in distinct climatic zones and the differences are primarily attributed to the regional differences in available water either in land or in the atmosphere. Consequently, the studies of the regional differences in land surface processes to a large extent are the analyses on how the arid climate for different intensities affects the land surface processes. For radiation components, downward short-wave radiation decreases with the latitude increasing, and the upward short-wave radiation is largest in the arid region and smallest in the cold region. The downward long-wave radiation is strongest in the cold region and weakest in the Loess Plateau while the upward long-wave radiation is obvious in the arid region and weak in the cold region. For energy components, 70% of the land surface available energy is consumed by heating the atmosphere in the arid region, and the remaining 30% is used for evaporation and heating the soil. In the Loess Plateau, however, only 30% of energy goes to atmosphere heating and 50% is lost to evaporation. Roughly half the energy is lost to evaporation in the cold region, and most of the other half is used for heating atmosphere.