Snow and land cover induced surface albedo changes in Northeast China during recent decades

The land surface albedo in Northeast China has been significantly changed by global climate change and anthropogenic activities over the past several decades. To determine the magnitude and causes of these albedo changes, we evaluated the land surface albedo trends and their causes in Northeast China from 1982 to 2015 using satellite-derived albedo, snow cover, and land cover/use data. The results show that the regional mean trend of the land surface albedo in Northeast China exhibited a strong increasing trend (0.0035 decade −1 ) in spring. Significant increasing trends in land surface albedo were identified in the Hulunbuir Grasslands, Sanjiang Plain, and western and central Songnen Plain, while significant decreasing albedo trends were identified in the Greater and Lesser Khingan Mountains, and the Liaoxi Hills. Our results indicate that the increase in the land surface albedo in Northeast China was primarily driven by the snow cover extent (SCE) and snow cover phenology. The increase in the land surface albedo in spring can be explained by the expansion of the SCE and the delay of the snow end date (SED). Moreover, the land surface albedo in winter and spring was enhanced by the land cover changes (e.g., deforestation and reclamation) due to the vegetation-masking effect on the snow cover. The results of this study can improve our understanding about the impacts of global climate change and human influences on the land surface albedo, and provide theoretical and policy bases for environmental protection and climate engineering.