Spatiotemporal patterns of snow cover retrieved from NOAA-AVHRR LTDR: a case study in the Tibetan Plateau, China

Abstract

Snow cover plays an important role in hydrological processes and seasonal water balance. Especially in the Tibetan Plateau (TP), snow cover is an important source of the Yangtze River, Yellow River and Lancang River (SRYYL), which greatly influences regional water balance. In this study, we quantified the temporal trend and spatial variation of snow cover across the TP by calibrating and developing the Advance Very High Resolution Radiometer (AVHRR) Long Term Data Record (LTDR)-derived snow cover products during 1982-2011. We also examined the relationship of snow cover with temperature and precipitation over the TP during 1982–2011. The results indicate that seasonal snow cover generally starts to accumulate from central plateau in October, while significant melting starts to occur from the southeastern plateau in May of following year. The long-term variability of snow cover is characterized by the tendency for a slight decrease in the mean snow coverage during the period of hydrological year (HY) 1982–1993 and a slight increase from HY2001 to 2011, but the total snow cover area remains relatively stable over the past 30 years. The results also show that temperature plays a critical role in controlling the snow cover days.

Keywords

• snow cover
• temporal-spatial variation
• noaa-avhrr ltdr
• tibetan plateau