资源科学 ›› 2020, Vol. 42 ›› Issue (5): 907-919.doi: 10.18402/resci.2020.05.09

• 气候资源 • 上一篇    下一篇

渭河流域潜在蒸散量变化的气候归因

郭梦瑶1, 佘敦先1,2(), 张利平1,2,3, 汤柔馨1, 赵鹏雁1   

  1. 1.武汉大学水资源与水电工程科学国家重点实验室,武汉 430072;
    2.海绵城市建设水系统科学湖北省重点实验室,武汉 430072;
    3.黄冈师范学院旅游与地理科学学院,黄冈 438000
  • 收稿日期:2018-11-19 修回日期:2019-06-16 出版日期:2020-05-25 发布日期:2020-07-25
  • 通讯作者: 佘敦先
  • 作者简介:郭梦瑶,女,陕西汉中人,博士研究生,主要从事气候变化和水文模拟研究。E-mail: mengyao_guo@whu.edu.cn
  • 基金资助:
    国家自然科学基金项目(41877159);家重点研发计划项目(2017YFA0603704)

Climate explanation of the potential evapotranspiration changes in Weihe River Basin

GUO Mengyao1, SHE Dunxian1,2(), ZHANG Liping1,2,3, TANG Rouxin1, ZHAO Pengyan1   

  1. 1. State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China;
    2. Hubei Provincial Key Laboratory of Water System Science for Sponge City Construction, Wuhan 430072, China;
    3. Huanggang Normal University, Huanggang 438000, China
  • Received:2018-11-19 Revised:2019-06-16 Online:2020-05-25 Published:2020-07-25
  • Contact: Dunxian SHE

摘要:

潜在蒸散量的变化及其归因分析是认识水文过程及其对气候变化响应的重要途经。本文利用FAO Penman-Monteith公式估算渭河流域1960—2016年的潜在蒸散量,并通过敏感性分析和基于全微分法的贡献评估,定量研究气象因子(太阳辐射、风速、相对湿度、平均气温)的变化对潜在蒸散量变化的影响。结果表明:①近57年来,年潜在蒸散量呈轻微增长趋势(0.239 mm/a),多年平均潜在蒸散量在流域上的空间分布特点为东高西低,北高南低,自东北向西南递减;②年潜在蒸散量对气象因子变化的敏感性高低顺序为相对湿度>太阳辐射>平均气温>风速,其中对气温和风速的敏感性会随着海拔的升高而降低;③气象因子变化对年潜在蒸散量变化的贡献大小顺序为平均气温>风速>相对湿度>太阳辐射,太阳辐射和风速的下降对年潜在蒸散量变化的负效应被平均气温升高和相对湿度减小对其的正效应所抵消,最终使得渭河流域年潜在蒸散量在1960—2016年呈微弱增加趋势。研究还发现,气象因子之间的相关性可能会影响它们对于潜在蒸散量变化的独立贡献,实际情况下,可以在考虑各因子相互作用的前提下对潜在蒸散量的归因给予充分讨论。本文结果对于理解气候变化对水循环的影响机理和加强区域应对气候变化的能力有一定意义。

关键词: 潜在蒸散量, 气候变化, 气象因子, 敏感性系数, 全微分法, 归因分析, 渭河流域

Abstract:

Analyzing the changes in potential evapotranspiration (ET0) and the attribution is an important way to understand hydrologic process and its response to climate change. In this study, after applying the FAO Penman-Monteith equation to estimate the ET0 in the Weihe River Basin for the period of 1960-2016, the differential method was employed to quantify the contribution of the four meteorological factors, i.e. solar radiation (Rs), wind speed (u2), relative humidity (RH), and average temperature (T), to the ET0 changes. The main results are shown below. During the 57 years, annual ET0 showed a slightly increasing trend of 0.239 mm/a, and multi-year average annual ET0 increased from the west to the east and from the south to the north of the basin spatially. We found that annual ET0 was most sensitive to RH, followed by Rs and T, and least sensitive to u2. Moreover, the sensitivity coefficients of T and u2 decreased with increasing elevation. From the perspective of contribution, the changes in T contributed most to the changes of annual ET0, followed by u2 and RH, and the changes in Rs showed the smallest contribution to annual ET0 changes. Generally speaking, the negative effects caused by the decrease in Rs and u2 to annual ET0 changes were offset by the positive effects caused by the increase in T and decrease in RH, which finally resulted in the increasing trend in annual ET0 during 1960-2016 in the whole basin. Since the correlation among the meteorological factors may influence their individual contribution to ET0 changes, we can fully discuss the attribution of ET0 changes by considering the interactions between these factors in practice. This study is significant for understanding the influence mechanism of climate change to hydrologic cycle as well as improving our capacity to cope with climate change regionally.

Key words: potential evapotranspiration, climate change, meteorological factor, sensitivity coefficient, total differential method, attribution analysis, Weihe River Basin