Assessing Agricultural Vulnerability to Climate Change Using NDVI Data Products

Abstract

Higher temperature and altered rainfall patterns accompained by extreme weather events are being considered indications of climate change.These factors impact vegetation growth in natural forest,open scrub and in agricultural land.Vegetation index based on satellite data was used to analyse agricultural vulnerability in india to understand impact of rainfall variability.time-series Normalized Difference Vegetation Index(NDVI) data products obtained from AVHRR(1982 to 2006) and MODIS (2000-2011) were analyzed to assess spatial and temporalvariability.Coefficient of variation of maximum NDVI was accessed for the study period and results were corroborrated with standard precipitation index(SPI) instead of actual rainfall. Resolution of AVHRR time-series data fascilitated study at regional-scale while MODIS datasets with 250m pixel resolution helped in identifying vulnerability at district-level.Study indicated that over 241 Mha areas in the country may not be vulnerable to rainfall variability induced climate change while over 81.3 Mha in arid,semi arid and dry sub-humid regions may be vulnerable.Study indicated that over 12.1 and 1.81 Mha of kharif cropland would be mildly and severally vulnerable while 6086 and 0.5 Mha of Rabi cropland may be adversly affected in a similar manner.Study indicated that length of cropping season was decreasing due to delay in start of season.The paper also prevents analysis of variations in SPI and resultant NDVI in typical drought and flood years in the country.