Increasing western US forest wildfire activity: sensitivity to changes in the timing of spring
Document Type: Journal Article
Author(s): A. L. Westerling
Publication Year: 2016

Cataloging Information

  • Arizona
  • Cascades Range
  • evapotranspiration
  • fire frequency
  • fire management
  • fire size
  • forest
  • forest management
  • lightning caused fires
  • New Mexico
  • precipitation
  • season of fire
  • wildfire
  • wildfires
Record Maintained By:
Record Last Modified: June 1, 2018
FRAMES Record Number: 55098
Tall Timbers Record Number: 33011
TTRS Location Status: Not in file
TTRS Call Number: Available
TTRS Abstract Status: Okay, Fair use

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.


Prior work shows western US forest wildfire activity increased abruptly in the mid-1980s. Large forest wildfires and areas burned in them have continued to increase over recent decades, with most of the increase in lightning-ignited fires. Northern US Rockies forests dominated early increases in wildfire activity, and still contributed 50% of the increase in large fires over the last decade. However, the percentage growth in wildfire activity in Pacific northwestern and southwestern US forests has rapidly increased over the last two decades. Wildfire numbers and burned area are also increasing in non-forest vegetation types. Wildfire activity appears strongly associated with warming and earlier spring snowmelt. Analysis of the drivers of forest wildfire sensitivity to changes in the timing of spring demonstrates that forests at elevations where the historical mean snow-free season ranged between two and four months, with relatively high cumulative warm-season actual evapotranspiration, have been most affected. Increases in large wildfires associated with earlier spring snowmelt scale exponentially with changes in moisture deficit, and moisture deficit changes can explain most of the spatial variability in forest wildfire regime response to the timing of spring. This article is part of the themed issue ' The interaction of fire and mankind'. © 2016 The Author(s) Published by the Royal Society. All rights reserved.

Online Link(s):
Westerling, A. L. 2016. Increasing western US forest wildfire activity: sensitivity to changes in the timing of spring. Philosophical Transactions of the Royal Society B-Biological Sciences, v. 371, no. 1696, p. 50178. 10.1098/rstb.2015.0178.