Almost every time we have a major wildfire, alarmists blame global warming and claim that such warming will increase the incidence of wildfires. They also often claim that the number of wildfires is increasing. Their argument seems logical at first, higher temperatures and less precipitation will dry out forests making them more susceptible to wildfire.

The graph below compiled by C3Headlines using data from the National Interagency Fire Center in the U.S. and the National Forestry Database in Canada shows that the number of wildfires has decreased dramatically since 1970 and has remained relatively constant since the mid 1980s. The number of acres burned, however, has slightly increased and that may have to do with wildfire fighting decisions.

These numbers suggest some possible conclusions: either global warming does not have much influence on the number of wildfires, in contrast to alarmist claims, or there has not been sufficient warming since 1970 to test the hypothesis. Fire incidence could also reflect the time and severity of cyclic drought.

I’ve also included below the UAH lower tropospheric temperature record since 1979 when satellites began measuring global temperature.

Meanwhile, NASA says “Climate Models Project Increase in U.S. Wildfire Risk” The analysis was based on current fire trends and predicted greenhouse gas emissions. Time will tell if this is just another “garbage in, garbage out” computer simulation.

See also:

Mega-fires in Southwest due to forest mismanagement

Drought in the West

Droughts in the Southwest put in perspective

USDA says carbon dioxide can reverse effects of drought

From April 3 to 5, approximately 70 people, representing various federal, state, and local agencies, researchers and practitioners, gathered at the University of Arizona’s Biosphere 2, north of Tucson for the 2012 Southwest Wildfire Hydrology and Hazards Workshop. The purpose of the workshop was to: 1) share the most recent research regarding post-fire hydrology and hazard assessments and mitigation and warning systems; and 2) discuss ideas for bridging funding gaps for research and warning system implementation.

Thirty papers presented at the workshop are available from the Arizona Geological Survey document repository here. The files consist mostly of power point presentations and PDFs. I recommend beginning with the first paper (50 pages) on the list (see here) which gives an overview of the proceedings.