Spatial and temporal variation in primary productivity (NDVI) of coastal Alaskan tundra: Decreased vegetation growth following earlier snowmelt

► Field NDVI sampling clearly resolved productivity patterns for arctic vegetation. ► Reduced vegetation productivity (NDVI) occurred in years with earlier snowmelt. ► Reduced precipitation and soil moisture best explained this reduced productivity. ► MODIS could not resolve snowmelt dates, growing season length, or peak NDVI. ► Field optical monitoring avoids cloud contamination that plagues satellite NDVI.