Climate Change, Reduced Arctic Ice, the Altered Pacific Jet Stream and the California Wildfire Season: Coincidence?

The effects of climate change are examined in regard to its impact on the Northern California fire season. Specifically, the teleconnection between reduced Arctic sea ice and resulting changes in the upper level jet-stream pattern was found to produce an anomalously strong, quasi-stationary high pressure ridge off the West Coast of the United States. Not only did this upper air pattern produce significant precipitation deficits and record drought across the region, but it also produced more critical and longer lasting Foehn wind events across Northern California, during the late fall and early winter months of 2013, thus extending the length of the typical fire season by several weeks.

Recent research has attributed this anomalous East Pacific blocking pattern to the extreme drought conditions persisting across California since 2012. Some of the drought and record dry fuel conditions will be examined along with the anomalous offshore/Foehn wind occurrences in conjunction with increased wildfire activity after the end of the traditional Northern California fire season.