Evaluation of MODIS Snow and LST Data in Arunachal Pradesh: Heat Pump or Freezer
Deka Baruah, Ujjal; Saikia, Anup
Gauhati University, INDIA

The NSIDC (National Snow Information Centre) archives and snow cover and sea ice data products from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on NASA's Earth Observing System (EOS) Aqua and Terra satellites. The MODIS/Aqua Snow Cover Monthly MYD10CM data set used in the study, consists of 7200 column by 3600 row global arrays of snow cover in a 0.05 degree Climate Modeling Grid (CMG). The MODIS snow cover data are based on a snow mapping algorithm that employs a Normalized Difference Snow Index (NDSI) and other criteria tests. Additionally MODIS MYD11CMLST (Land Surface Temperature)data comprising of daytime and nighttime LSTs was used. The objective of this paper is to validate MODIS snow and LST data, to evaluate the relationship between LST and snow andto estimate the temporal change in LST and snow cover in Arunachal Pradesh (AP).Data was processed for a period of 10 years for randomlyselected study sites in Arunachal Pradesh using a geographic information system (GIS). When plotted in scatter diagram a linear positive relationship between 8- daily LST and monthly average snow is seen. This means that the study sites are also experiencing more heat and less snow fall with increases in temperatureand other climaticattributes. The fast retreating snow line shift in the month of July and heavy snowfall in January is one of the evidences of the effect of heat over the earth’s surface. Keywords: LST, NDSI, Arunachal Pradesh