| 珠江流域实际蒸散发与潜在蒸散发的关系研究 |
| |
| 引用本文： | 李修仓,姜彤,吴萍,王艳君,苏布达.珠江流域实际蒸散发与潜在蒸散发的关系研究[J].大气科学学报,2016,39(5):692-701. |
| |
| 作者姓名： | 李修仓 姜彤 吴萍 王艳君 苏布达 |
| |
| 作者单位： | 南京信息工程大学 气象灾害预报预警与评估协同创新中心, 江苏 南京 210044;国家气候中心, 北京 100081;南京信息工程大学 气象灾害预报预警与评估协同创新中心, 江苏 南京 210044;国家气候中心, 北京 100081;南京信息工程大学 气象灾害预报预警与评估协同创新中心, 江苏 南京 210044;国家气候中心, 北京 100081;中国气象科学研究院, 北京 100081;南京信息工程大学 气象灾害预报预警与评估协同创新中心, 江苏 南京 210044;南京信息工程大学 气象灾害预报预警与评估协同创新中心, 江苏 南京 210044;国家气候中心, 北京 100081 |
| |
| 基金项目： | 国家自然科学基金资助项目（41571494）；江苏省普通高校研究生科研创新计划项目（KYLX15_0858） |
| |
| 摘 要： | 采用水量平衡模型和Penman公式分别计算了珠江流域七个子流域1961—2000年实际蒸散发(I_(ETa))和潜在蒸散发(I_(ETp)),并对供水条件变化下I_(ETa)与I_(ETp)的关系进行了定量化分析,对各子流域I_(ETa)和I_(ETp)关系的理论从属性进行判定,主要结论如下:1)珠江流域年实际蒸散发量远低于潜在蒸散发量,多数子流域I_(ETa)值不到I_(ETp)值的1/2。7个流域面积加权平均I_(ETa)为681.4 mm/a,I_(ETp)为1 560.8 mm/a。从蒸散发的变异性来看,则实际蒸散发I_(ETa)的变异性明显要高于潜在蒸散发I_(ETp)。2)东江、西江、北江、柳江和盘江等5个流域实际蒸散发I_(ETa)都与降水量呈现正相关关系,韩江、郁江两个流域I_(ETa)随降水变化的变化趋势不明显。各子流域的潜在蒸散发I_(ETp)与降水量呈现显著负相关关系。7个子流域平均情况下,随着降水量的增加,I_(ETa)呈现明显的增加趋势,而I_(ETp)呈现明显的下降趋势。3)通过对降水量P与实际蒸散发I_(ETa)及潜在蒸散发I_(ETp)的联合回归方程P-IET回归系数的T检验,判定韩江、柳江和盘江等三个子流域以及七流域面积加权平均I_(ETa)与P和I_(ETp)与P的关系满足理论意义上的严格互补相关;东江、西江、北江等三个流域I_(ETa)与P和I_(ETp)与P的关系满足"非对称"互补相关。4)基于极端干旱和极端湿润的边界条件,推导出非对称条件下的实际蒸散发互补相关理论模型。
|
| 关 键 词： | 实际蒸散发 潜在蒸散发 正比假设 互补相关 珠江流域 |
| 收稿时间： | 2013/3/1 0:00:00 |
| 修稿时间： | 2013/5/18 0:00:00 |
Relationship between actual evapotranspiration and potential evapotranspiration in the Pearl River basin |
| |
| LI Xiucang,JIANG Tong,WU Ping,WANG Yanjun and SU Buda.Relationship between actual evapotranspiration and potential evapotranspiration in the Pearl River basin[J].大气科学学报,2016,39(5):692-701. |
| |
| Authors: | LI Xiucang JIANG Tong WU Ping WANG Yanjun and SU Buda |
| |
| Institution: | Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China;National Climate Center, Beijing 100081, China;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China;National Climate Center, Beijing 100081, China;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China;National Climate Center, Beijing 100081, China;Chinese Academy of Meteorological Sciences, Beijing 100081, China;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China;National Climate Center, Beijing 100081, China |
| |
| Abstract: | As the average global temperature increases,it is generally expected that the air near the surface should be drier,which should result in an increase in the rate of evaporation from terrestrial open water bodies.However,despite the observed increases in average temperature,observations from many regions show that the rate of evaporation from open pans of water has been steadily decreasing over the past 60 years.It is important to understand why pan evaporation has decreased despite the increases in average temperature in order to make more robust predictions about future changes in the hydrological cycle.One of the explanations is that the decrease in evaporation is caused by large and widespread decreases in sunlight resulting from increasing cloud coverage and aerosol concentration.Previous work demonstrated that,in non-humid environments,measured pan evaporation is not a good measure of potential evaporation(IETp);moreover,in many situations,decreasing pan evaporation actually provides a strong indication of increasing terrestrial actual evaporation(IETa).The key issue in research on the hydrological cycle is how to estimate IETa.As we know,it is difficult to obtain a sufficient volume of reliable instrumental IETa measurements,so scientists have made use of a range of theoretical,especially climatological,methods for this purpose.There are two main theories to estimate IETa from IETp.At the regional scale,the Penman hypothesis is a common approach to reducing IETp to IETa in response to the water stress,which is given by a function of soil water availability.This is often questioned by the Bouchet complementary relationship theory,in that the Penman hypothesis does not consider the complex surface-atmosphere interactions at the catchment scale.The discrepancy between the Penman and Bouchet hypotheses is especially highlighted in non-humid regions.In this paper,we select the Pearl River basin of southern China as the study area,and the relationship between IETa and IETp is analyzed in depth.Firstly,the actual evapotranspiration(IETa) and potential evapotranspiration(IETp) are calculated,respectively based on the water balance model and the Penman formula,in seven sub-basins of the Pearl River Basin from 1961 to 2000.The relationship between IETa and IETp under the change in water supply conditions is quantified and compared among the seven sub-basins.The results show that:(1)The annual IETa is much lower than the IETp,and the mean annual IETa values are less than 1/2 of the IETp in most of the sub-basins.The area-weighted average IETa of the seven sub-basins is 681.4 mm yr-1,and the IETp is 1 560.8 mm yr-1.The variability of the IETa is more significant than the variability of the IETp.(2)IETa in five sub-basins(Dongjiang,Xijiang,Beijiang,Liujiang and Panjiang) is positively correlated with the precipitation(P),but in the other two sub-basins (Hanjiang River and Yujiang),the correlations between IETa and P are not so obvious.The IETp of all sub-basins shows a significant negative correlation with P.Given the condition of increasing P,the annual mean IETa of the seven sub-basins shows an obvious increasing trend,while the IETp presents a clear downward trend.(3)A joint regression equation(P-IET) between IET(containing IETa and IETp) and precipitation is constructed for every sub-basin,and t-tests of all the regression coefficients are used to determine if the relationship between P and IETa or IETp belongs to the Bouchet complementary relationship theory or the Penman proportional hypothesis theory.The results confirm the applicability of the former theory in all of the seven sub-basins except Yujiang.In Hanjiang,Liujiang and Panjiang,the relationship between IETa and IETp fits the complementary relationship theory completely.Furthermore,in three sub-basins(Dongjiang,Xijiang and Beijiang),the relationship between IETa and IETp belongs to the "asymmetry complementary relationship".(4)A number of previous studies generally lend support to the IETa formula based on the completely symmetric complementary relationship theory,but not the "asymmetry complementary relationship" theory.A schematic diagram of the "asymmetric complementary relationship" between IETa and IETp is given in the present paper.Based on strict logical inference,and at the same time considering the boundary conditions of extreme drought and extreme wet conditions,this paper gives the IETa model under the "asymmetry complementary relationship". |
| |
| Keywords: | actual evapotranspiration potential evapotranspiration Penman proportional hypothesis complementary relationship the Pearl River basin |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《大气科学学报》浏览原始摘要信息 |
| 点击此处可从《大气科学学报》下载免费的PDF全文 |
|
