新安江模型在高寒无资料地区的水文过程模拟(英文)

由于冰雪的存在及缺乏地面观测站点资料,高寒地区的水文模拟研究一直面临很大的困难。遥感数据能够提供大范围时空尺度上的地面信息对无资料地区有很大帮助。MODIS数据具有较高的时空分辨率深受人们关注。本文以长江上游泥曲流域为例,探求将MODIS遥感数据与地面气温数据相结合对新安江模型径流模拟的帮助,方法步骤如下:(1)建立MODIS雪覆盖面积与流域周围站气温关系,获取气温阈值;(2)依据气温阈值判别降水形式并计算融雪水当量;(3)将雨雪分离后的降水信息输入新安江模型模拟径流,并与新安江模拟结果(未考虑雨雪分离)和实测径流进行比较。研究结果显示改进方案(考虑雨雪分离)模拟效果更好,将有助于提高新安江模型在高寒无资料地区的径流模拟精度,为高寒无资料地区水资源管理及生态需水研究提供帮助。

The Simulation of Hydrological Processes in an Ungauged Alpine Basin by Using Xinanjiang Model

It is very difficult to simulate hydrological processes in alpine basin because of the impact of ice-snow and limited availability of ground observation stations.Satellite imagery is an attractive alternative to supplement ground based data in ungauged basin.The Moderate-Resolution Imaging Spectroradiometer (MODIS) satellite sensors are particularly attractive due to their high temporal and spatial resolution.The objective of this study is to integrate temperature data with meteorological stations and SCA (Snow Covered Area) estimated from MODIS into Xinanjiang Model and test if MODIS data could be helpful for runoff modeling in an ungauged alpine basin.The analysis was performed for Niqu Basin in the upper reach of Yangtze River.The study was carried out as follows.Firstly,a critical temperature was acquired according to SCA from MODIS data for judging the periods with snow accumulation,snow melting and no snow.Then the precipitation form was identified and snowmelt water equivalent was computed accordingly.Finally the classified precipitation was as input to the Xinanjiang Model for simulating runoff series.The simulated runoff data by Xinanjiang Model with such a modified input were compared with pure precipitation input.The result indicated that model performance with the modification scheme of precipitation was better than that with original input of precipitation.The result suggests the potential for developing modification scheme and the possibility of improving the accuracy of the prediction of hydrological processes for water resources management and ecological water demand in ungauged alpine basin by Xinanjiang Model.