AP misleads the public, again, saying man made global warming worsens wildfires
Guest essay by Larry Hamlin: Study claimed by climate fear press to support these claims addresses many contributing factors
The climate fear media is at it again this time alleging claims that a new study shows that global warming is making wildfires in the western U.S. worse. A link to one of these misleading alarmist articles, written by AP’s Seth Borenstein, is here:
http://hosted.ap.org/dynamic/stories/U/US_SCI_WILDFIRES_AND_WARMING?SITE=AP
The study addressed in these alarmist press articles is titled “Large wildfire trends in the western United States, 1984-2011″ published in Geophysical Research Letters with the abstract available here: http://onlinelibrary.wiley.com/doi/10.1002/2014GL059576/abstract
The study addresses large wildfires (greater than 1000 acres) in the western U.S. across nine different study defined ecoregions which have occurred since 1984. The data shows that the total regional burn area has increased by about 87,700 acres per year with an increase of 7 additional regional fires per year during this period. The western U.S. area and regional ecoregions addressed in the study are shown below.
While the climate alarmist press loudly proclaim that “man made climate change is to blame” for these findings the actual study is much more circumspect about what the contributors are that could be impacting the results.
Even in the abstract to this study other factors are identified that the authors believe contribute to these results including the impacts of invasive species and consequences of past fire management practices in addition to changes in climate and in particular increasing drought severity.
Nowhere in the report do the authors specifically articulate that “man made climate change is to blame” for the studies findings.
The study further elaborates on invasive species and past fire management practices noting the following;
“For example, invasion of nonnative annual grasses across large areas of the Great Basin [Balch et al., 2013] has been linked to increases in fire frequency and area burned in recent decades. The role of past fire management practices on trends in fire variables varies by ecoregion. Past fire suppression has led to changes in fuels, fire frequency, and fire intensity in some southwestern ponderosa pine [FulĂ© et al., 1997] and Sierran forests [Collins and Stephens, 2007] but has had relatively little impact on fire activity in portions of the Rocky Mountains [Schoennagel et al., 2004] and in southern California chaparral [Moritz et al., 2004]. Changes in fire fighting practices over time (e.g., more frequent use of intentional burning to clear fuels as a fire suppression tactic) may have had impacts on mapped burn area boundaries. The effects of human development vary regionally, in some cases increasing fire activity and in others decreasing it [Hawbaker et al., 2013; Syphard et al., 2007].”Further the study highlights the relationship between western U.S. drought severity and increasing large fire trends with the following:
“Ecoregions with increasing trends in the number of large fires and total fire area also displayed increasing trends in drought severity. The geographically broad and coherent nature of fire and climate trends across much of the study area implicates climate as a dominant driver of changing fire activity in the western U.S. Due to complex interacting influences on fire regimes across the western U.S. and the relatively short period analyzed by this study, care must be exercised in directly attributing increases in fire activity to anthropogenic climate change. Even so, these changes in fire activity are a reflection of long-term, global fire trends that will likely occur with increased temperature and drought severity in coming decades.”The study does not make any attribution to “man made” actions being responsible for the large wildfire trend results. Instead the study identifies regional invasive species, past fire management practices, increases in western U.S. regional drought severity and increasing regional temperatures as driving the results.
While this wildfire study was limited to large wildfires in the western U.S. region Dr. John Christy provided testimony to Congress in December 2013 addressing wildfire data from the National Interagency Fire Center for the entire country showing no increasing nationwide wildfire trends since 1986 as shown below. Dr. Christy’s testimony can be found here:
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