基于GsMAP的尼洋河流域降水时空分布特征研究

鉴于尼洋河地区实测降雨资料缺乏,卫星降雨产品具有显著优势,基于GsMAP降雨产品数据和地面观测站点数据,利用降雨量年内分配特征的δ方法建立卫星降雨校正公式,分析流域降雨量的时空分布特征。结果表明,实测站点月降雨量校正结果较好,相关系数达0.954,年尺度的站点降雨相关系数为0.54,降雨量空间分布呈现出自西向东递增的特点。卫星降雨观测在西部地区存在低估,东部地区有一定程度的高估,在降雨梯度分布上,流域在3500~4000m高程段降雨量呈上升趋势,其他高程段均为显著下降,整体变化率为-104mm/km。流域的年均面平均降雨量为699mm,降雨多集中于夏季,且有逐年增加趋势。

Temporal and Spatial Distribution Characteristics of Precipitation in the Niyanghe River Basin Based on GsMAP

In view of the lack of measured rainfall data in the Niyanghe basin,satellite rainfall has significant advantages,based on GsMAP rainfall product data and ground observation site data,the satellite rainfall correction formula was established using theδmethod of annual rainfall distribution characteristics.And then the temporal and spatial distribution of rainfall in the basin was analyzed.The results show that the monthly rainfall correction of the measured stations is good with a correlation coefficient of 0.954,and the annual rainfall correlation coefficient of the station is 0.54.The spatial distribution of rainfall shows a characteristic of increasing from west to east.Satellite rainfall observations are underestimated in the western region and overestimated to a certain extent in the eastern region.In the gradient distribution of rainfall,the rainfall in the watershed at the elevation of 3 500-4 000 mshows an upward trend,and other elevations are significantly reduced,the overall rate of change is-104 mm/km.The average annual rainfall of the river basin is699 mm.Most of the rainfall is concentrated in summer,and it is increasing year by year.