A remote sensing based analysis of climate change in Sikkim supported by evidence from the field

The Himalayas hailed as the 'water towers of the world' feed many perennial rivers which form the lifeline of the Indian sub-continent. Climate change induced rising global temperatures and changing rainfall patterns are currently threatening the glaciers that feed the rivers. The combination of these factors is causing water stresses to a part of the world which is usually considered water abundant. Though there are some large-scale studies done in the Himalayas, regional analysis of changing rainfall patterns and their impacts on vegetation and agriculture is lacking. Here we focus on the Indian state of Sikkim located in the Eastern Himalayas to evaluate these issues using mixed methods. We use satellite data from PERSIANN and MODIS to characterise the regional rainfall, vegetation, and surface temperature trends between 2001 and 2019. While the analysis shows overall declining rainfall trends across most land cover classes, the trends in temperature are mostly positive for the period of study, with winter Land Surface Temperature (LST) values showing the largest area with marginally significant (p<0.1) positive trends. In contrast, such patterns are not observed for agriculture. However, the interviews corroborate that even agriculture is impacted, implying that the trends continue at finer spatial scales too. The lack of government support for adaptation and mitigation is also lamented placing the communities at a precarious position to continuing climate change.