Status: this preprint was under review for the journal TC but the revision was not accepted.
Spatiotemporal variation of snow depth in the Northern Hemisphere from 1992 to 2016
Xiongxin Xiao,Tingjun Zhang,Xinyue Zhong,Xiaodong Li,and Yuxing Li
Abstract. Snow cover is an effective best indicator of climate change due to its effect on regional and global surface energy, water balance, hydrology, climate, and ecosystem function. We developed a long term Northern Hemisphere daily snow depth and snow water equivalent product (NHSnow) by the application of the support vector regression (SVR) snow depth retrieval algorithm to historical passive microwave sensors from 1992 to 2016. The accuracies of the snow depth product were evaluated against observed snow depth at meteorological stations along with the other two snow cover products (GlobSnow and ERA-Interim/Land) across the Northern Hemisphere. The evaluation results showed that NHSnow performs generally well with relatively high accuracy. Further analysis were performed across the Northern Hemisphere during 1992–2016, which used snow depth, total snow water equivalent (snow mass) and, snow cover days as indexes. Analysis showed the total snow water equivalent has a significant declining trends (~ 5794 km3 yr−1, 12.5 % reduction). Although spatial variation pattern of snow depth and snow cover days exhibited slight regional differences, it generally reveals a decreasing trend over most of the Northern Hemisphere. Our work provides evidence that rapid changes in snow depth and total snow water equivalent are occurring beginning at the turn of the 21st century with dramatic, surface-based warming.
How to cite. Xiao, X., Zhang, T., Zhong, X., Li, X., and Li, Y.: Spatiotemporal variation of snow depth in the Northern Hemisphere from 1992 to 2016, The Cryosphere Discuss. [preprint], https://doi.org/10.5194/tc-2019-33, 2019.
Received: 15 Feb 2019 – Discussion started: 29 Apr 2019
Seasonal snow cover is an important component of the climate system and global water cycle that stores large amounts of freshwater. Our research attempts to develop a long-term Northern Hemisphere daily snow depth and snow water equivalent products using a new algorithm applying in historical passive microwave data sets from 1992 to 2016. Our further analysis showed the snow cover has a significant declining trend across the Northern Hemisphere, especially beginning at the new century.
Seasonal snow cover is an important component of the climate system and global water cycle that...