径流对气候变化的响应研究-以黄河上游河源区为例

为了研究气候变化对径流的影响,选择黄河上游河源区为典型流域,构建多变量Copula联合分布模型,分析流域内主要气象要素与径流的相互响应关系。通过对多元相依结构分析,得到主要气候变化要素与径流变化的定量关系。结果表明,黄河上游吉迈水文站以上流域,径流受气候变化影响明显。长期以来主要气象要素,气温、降水、潜在蒸发能力(Penman-Monteith公式计算)与径流量的相依度指数分别为0.03、0.46、0.13,且在不同时期影响径流变化的主导因素各异。黄河上游径流受降水、冰雪、冻土融水和地下水共同补给,径流自演化过程复杂。

Study on the runoff response to climate change-a case study of source region of the Yellow River

In order to better understand the runoff response to climate change in the upper reaches of the Yellow River, we develop joint distribution models base on multivariate Copula theory. And obtain the quantitative relationship between the main climate factors and runoff changes through the analysis of multiple dependent structures. The results show that the runoff at the JiMai gauging station affected by climate change obviously. In the past 53 years, the Copula dependent degree index of runoff and major meteorological factors, such as temperature, precipitation, potential-evaporation capacity (Penmanand-Monteith formula) are 0.03, 0.46, 0.13, while the dominant influencing meteorological factors of runoff changes are not the same for different stages. Recharged from precipitation, ice and snow, permafrost melt water and groundwater, the runoff show a complex evolutionary process.