December 4, 2012
NASA: Drier Climate Conditions, More Wildfires By 2050
Michael Harper for redOrbit.com — Your Universe Online
2012 has been a bad year for wildfires in the US. According to data collected by NASA, some 6.17 million acres (2.5 hectares) have been consumed by wildfire this year alone. While this is just short of the record set last year of 7.90 million acres, (3.2 hectares) it´s larger than the amount of burned land in 12 of the last 15 years that scientists have been keeping tabs on wildfires.
If some NASA climate models hold true, scientists predict the United States will become a drier place over the next 4 decades. This means the next several years could play host to more destructive and more frequent wildfire outbreaks.
These findings were presented today at the annual meeting of the American Geophysical Union in San Francisco.
Doug Morton with NASA´s Goddard Space Flight Center in Maryland presented these findings about the future of wildfires in America. The analysis of future wildfire trends had been based on greenhouse gas emissions, as well as current wildfire trends.
"Climate models project an increase in fire risk across the US by 2050, based on a trend toward drier conditions that favor fire activity and an increase in the frequency of extreme events," said Morton, according to a NASA statement.
Morton and his colleagues took data from climate projections as well as calculated results for years with low and high greenhouse emissions to come to this conclusion. In instances with both low and high greenhouse emission levels, these models suggested that America will see longer and stronger fire seasons for the next 30-50 years.
With more than 6 million acres of land ravaged by wildfires, 2012 is being called a “high fire” year. Current climate conditions suggest that America will see one of these high fire years once a decade. According to these new models, our nation could see as many as 2 to 4 of these high fire years per decade come 2050.
"Fire is an inherently global phenomenon, and the only practical way to track large-scale patterns and changes in fire activity is with satellites," explained Louis Giglio with the University of Maryland at College Park and Goddard.
As more fires have swept across the United States, so too have the emission levels in our nation increased. According to Chris Williams with Clark University in Worcester, Massachusetts, carbon emissions have more than doubled since the 19080s as a result of these wildfires.
Using satellite images, Williams and his team were able to judge how much carbon had been released into the atmosphere as a result of fires in the western part of the country.
Williams and his team have calculated that, on average, the amount of carbon emissions from fires have grown from an average of 8.8 million tons a year during 1984 to 1995 to an average of 22 million tons a year in between the years 1996 and 2008.
"With the climate change forecast for the region, this trend likely will continue as the western US gets warmer and drier on average," said Williams in a statement.
"If this comes to pass, we can anticipate increased fire severity and an even greater area burned annually, causing a further rise in the release of carbon dioxide."
Wildfires aren´t the only cause of these increased carbon emissions, however. According to Hsiao-Wen Lin at the University of California at Irvine, nearly 70 percent of these fires are prescribed fires and important to agricultural growth. Though these fires have been used for centuries to tend the Earth, Lin suggests looking at the data to understand if this sort of technique will be helpful in the long run.
"That means there is greater potential to manage fire emissions, even in a future, drier climate with more wildfires. We need to use cost-benefit analysis to assess whether reductions in agricultural fire emissions -- which would benefit public health -- would significantly impact crop yields or other ecosystem services," said Lin.