Spatial-temporal dynamic of snow cover in the Northern Hemisphere by Google Earth Engine
SUN Zhongtai
ZHANG Jiahua
WANG Xiaopeng
LI Shuaishuai
LI Yongsha
ZHANG Sha
BAI Yun
Abstract：Snow cover regulates the water cycle and energy exchange in most parts of the Northern Hemisphere(NH).It is important to study the temporal and spatial dynamic snow cover frequency(SCF),snow cover area(SCA)and snow cover phenology(SCP)in the NH.Based on Google Earth engine cloud platform and MODIS satellite data,this study analyzed the temporal and spatial variation characteristics of SCF and SCA in the NH from 2000 to 2019,as well as the large-scale variation and contribution of SCP.The results showed that there were obvious interannual and regional differences in the variation trend of SCA in the NH.The SCF decreased at the rate of 0.4～0.6(d/a)near Eurasia(55 °～65 ° N,30 °～120 ° E),Mongolia Plateau,Stanov Plateau and Greenland.The SCA in spring and winter in the NH decreased significantly,and the average annual downward trend in winter reached 1.9×105 km2.The number of snow cover duration days increased significantly in areas near Kazakh-stan and the Central Plains of North America,with an average annual increase of 1.1d.The change of SCP was mainly due to the change of snow cover end date,and the correlation between them was 0.89.The analysis of regional contribution to the change of SCP in the NH showed that the change of SCP in the NH was mainly dominated by the change of SCP in Eurasia,and the contribution rate was about 60％.
Keywords：snow coversnow cover phenologyMODISspatial-temporal variationNorthern Hemi-sphereGoogle Earth Engine
Publication Date：2025-02-28
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：10( 105-114 )