Snow Change In Manas River Basin And Its Relation To Runoff Of Manas River

Recent years , the dynamic research of snow is globe change research hotspot.This paper uses the 8 days synthetic data products MODIS/MOD10A2 snow cover which provided by NSIDC DAAC (National Snow and Ice Data Center Distributed Active Archive Center, USA)。In the entire research process, selected Nov.2000 to Apr.2009 Manas River basin involving MODIS image data as the source of remote sensing data, combined with 1:25 million in the Xinjiang region DEM data which China Meteorological Administration issued and other geographic information data extracted the Manas River snow cover map。Using KenSiWat hydrological station river runoff data and it related to weather stations to study the correlation with the snow cover, and also with Jan.4, 2003 of the TM data which provided by US Geological Survey (USGS) Administration to verified the accuracy of MOD10A2 data。We can get mainly following conclusions and results base on coordinating and analyzing the above data:1.Using EOS / MODIS 8 days synthetic data for monitoring snow cover can effectively reduce the cloud effects on sense of image, which regard the TM image data as "true value", the result of the accuracy rate is 95%,so the precision is preferly,it can be effectively implemented monitor snow on the ground in a period of time,based Nov.2000 to Apr.2009 even snow coverage, snow , the most snow cover coverage is December.2. The snow cover rate trend of Manas upriver region present low-high-low in 2000-2009.The average maximum of snow cover rate is0.876,and its standard deviation is 8%,the variety rang is lesser.3. The average runoff in Manas river about 14.459 hundred million stere in 1957-2007 past years,the runoff was increase in evidence at begin of middle 90th,distribute of annual runoff is odds,the percent of gross runoff in January to March,April to May,June to September,October to December is 4.38%,6.87%,80.14%,8.61%.4.With the snow coverage of different heights, obtained snow cover decay curve of different heights ,and snow melting rate of the first zone is fastest by the end of March, rapidly snow melt of the second zone start in the middle of April and complete in June,the first and second zone stop and remain stable until late June; the higher elevation of third zone is more stable start in March and arrive the minimum at the end of June; the snow cover rate of fourth zone more stable, the downward trend begin in late May and get minimum by the end of June.5.Investigated the relativity of snow cover and runoff, the correlation coefficient of between the average snow coverage in March and the runoff of April be about -0.8175, and through a significant level of 0.005 test;the correlation coefficient between the most snow cover month in winter and spring and the following year runoff of June is -0.6496, and through a significant level of 0.05 test; the correlation coefficient of between the average snow coverage in December and the following year runoff in May be about 0.5775, and through a significant level of 0.1 test.