Droughts Effects in Mountain Ecosystems

The 2012-2015 drought was an exceptional period of warm and dry weather that impacted water and ecological resources in the Lake Tahoe Basin (LTB). Although above average temperature and below average precipitation occurred in all four years, the patterns varied across years and in different parts of the LTB. Water year (WY) 2012 and 2015 were the most exceptional in terms of below average precipitation (30 and 36% below the long term average, respectively). In general the southern end and higher elevations of the LTB experienced the warmest drought. Overall Palmer Drought Severity Index (PDSI) was less severe than during 1987-1990 drought.