Detecting Arctic Change Using the Koppen Climate Classification Muyin Wang 1 James E. Overland 2 1 JISAO/UW, 2 PMEL/NOAA, Seattle, WA Photos from the Ayiyak River (Alaska) show an increase in shrubs. Sturm et al., 2001, Nature & Satellite NDVI The Koppen Classification TemperateDT>= 10 o C for 4 or more months BorealET>= 10 o C for 1-3 months Polar TundraFt0 o C