Abstract
Quantifying and attributing the phenological changes in snow cover are essential for meteorological, hydrological, ecological, and societal implications. However, snow cover phenology changes have not been well documented. Evidence from multiple satellite and reanalysis data from 2001 to 2014 points out that the snow end date (De) advanced by 5.11 (±2.20) days in northern high latitudes (52–75°N) and was delayed by 3.28 (±2.59) days in northern mid-latitudes (32–52°N) at the 90% confidence level. Dominated by changes in De, snow duration days (Dd) was shorter in duration by 5.57 (±2.55) days in high latitudes and longer by 9.74 (±2.58) days in mid-latitudes. Changes in De during the spring season were consistent with the spatiotemporal pattern of land surface albedo change. Decreased land surface temperature combined with increased precipitation in mid-latitudes and significantly increased land surface temperature in high latitudes, impacted by recent Pacific surface cooling, Arctic amplification and strengthening westerlies, result in contrasting changes in the Northern Hemisphere snow cover phenology. Changes in the snow cover phenology led to contrasting anomalies of snow radiative forcing, which is dominated by De and accounts for 51% of the total shortwave flux anomalies at the top of the atmosphere.
Highlights
Previous efforts have proved that snow cover phenology has remarkably changed in response to climate change
Five snow datasets are analyzed (Supplementary Table S1) in this study, including a reanalyzed dataset of daily snow depth generated by the Canada Meteorological Center (CMC)[26], a binary daily snow cover mask derived from the Interactive Multi-sensor Snow and Ice Mapping System (IMS)[27] and the Northern Hemisphere Weekly Snow Cover and Sea Ice Extent (NHSCE)27,28, 8-Day Level 3 snow cover fraction products (MOD10C2) derived from the Moderate Resolution Imaging Spectroradiometer Satellite (MODIS)[29] and the snow water equivalent (SWE) derived from the Near-real-time Ice and Snow Extent (NISE) dataset[30]
Based on the NHSCE dataset, the NH presents no noticeable changes in Do, an earlier De at 95% confidence level (CL), as well as an overall shorter duration days (Dd) between the winters of 1972/73 and 2007/0814
Summary
Previous efforts have proved that snow cover phenology has remarkably changed in response to climate change. Further studies are currently needed at a continental scale in order to better understand the changes in snow cover phenology, the mechanisms driving them, and their impacts on the Earth’s climate system. Snow cover phenology is highly sensitive to changes in temperature and precipitation Understanding how these climate change events featuring the high spatial heterogeneity influence the snow cover phenology has meaningful consequences for water management, sustainable development of ecosystems, and prediction of catastrophic climate related events. The objective of this study is to quantify and understand the spatial and temporal changes of snow cover phenology and to point out their causes and consequences. This knowledge is critical for assessing and projecting the future climate. The specific definitions of Do, De, and Dd for each dataset are described in Methods
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
