Fire on the Mountain

California Feels the Heat of Global Warming

Daniel J. Weiss outlines a plan for reducing the effects of global warming that could cause more severe wildfires.

The horrific wildfires in southern California have already forced an estimated 500,000 people from their homes. More than 1,600 homes and buildings

have been destroyed by the wind whipped flames. Brave fire fighters valiantly battle the blaze against long odds to reduce the threat to relatively unscarred places. These fires, which range from northern Los Angeles County to the Mexican border, have produced so much smoke that they are visible in satellite pictures hundreds of miles from Earth. They are a terrible human tragedy.

Weather this year in Southern California probably contributed to the ferocity of these fires. This year, Los Angeles went 150 days without measurable rainfall. The lack of moisture dries trees and brush, which makes them much more susceptible to combustion from embers and flames carried by swirling winds.

Global warming’s effect on wildfires has already arrived. As Prof. A.L. Westerling et al. reported in Science last summer, their study of wildfire activity from 1970 to 1986, and 1987 to 2003, determined that “warming and earlier spring increase western U.S. forest wildfire activity.” They found:

“Increased wildfire activity over recent decades reflects subregional responses to changes in climate … [The increase in fires] was marked by a shift toward unusually warm springs, longer summer dry seasons, drier vegetation (which provoked more and longer burning large wildfires), and longer fire seasons.”

In 2006, it is estimated that wildfires caused 28 deaths, including 20 fire fighters. They also caused over $1 billion in damages. In addition to the human cost, the federal government spent nearly $2.5 billion for fire suppression in fiscal years 2005-06. The federal government spent $1 billion in 2007 before the California blazes. The current fire could easily lead to record suppression spending this year.

Perhaps most frightening is that massive, destructive wildfires could occur even more frequently and with greater ferocity due to global warming. Earlier this year, the Nobel Prize winning Intergovernmental Panel on Climate Change described how “a warming climate encourages wildfires through a longer summer period that dries fuels, promoting easier ignition and faster spread.” The IPCC noted that “warmer summer temperatures are projected to extend the annual window of high fire ignition risk. … North America very likely will continue to suffer serious loss of life and property.”

Forest fires can also add to global warming from sources that normally reduce greenhouse gases. Forests, brush, and other biomass can “capture” the carbon pollution responsible for global warming, and can offset emissions from other sources. Unfortunately, the increase in fires that burn this fuel also releases millions of pounds of greenhouse gases. The Westerling study also predicted that “if wildfire trends continue … this biomass burning will result in carbon release, suggesting that the forests of the western United States may become a source of increased atmospheric carbon dioxide rather than a sink, even under a relatively modest temperature-increase scenario.”

In the earlier part of this decade, the logging industry and their Congressional allies argued that “fuels management,” such as clearing brush and logging trees would reduce wildfire frequency and severity. The Westerling study found that drought and climate were more responsible for fires. Their examination of climate records and tree growth history “provide evidence that western forest wildfire risks are strongly positively associated with drought concurrent with the summer fire season.”

In other words, drought and high temperatures are primarily responsible for wildfires. Reductions in drought and temperature increases should reduce wildfire threats, and fuel management and logging will do little to limit the threat.

We can lessen the threat of future calamities like the southern California wildfires by reducing the carbon dioxide pollution that causes global warming. The first step is the final the passage of an energy bill that includes new fuel economy standards of 35 miles per gallon by 2020, a 15 percent renewable electricity standard, a sustainable renewable fuels standard with environmental safeguards, energy efficiency measures for buildings and appliances, and investments in new clean energy technologies paid for by closing tax loopholes for big oil companies.

If Congress took the most efficient renewable measures from the Senate and House energy bills, it would reduce global warming pollution by nearly 20 percent by 2030 compared to business as usual. This would be an important down payment on global warming pollution reductions.

We must also cap and cut greenhouse gases from power plants, industry, and other sources. America’s Climate Security Act, S. 2191, introduced by Senators Joe Lieberman (I-CT) and John Warner (R-VA) would reduce global warming pollution by 15 percent from covered sources by 2020, and by 70 percent by 2050. This bill provides a solid foundation for efforts to reduce global warming pollution, but the addition of several critical provisions would significantly improve the bill, including:

  • Mandating that new coal fired power plants reduce their pollution by 85 percent using carbon and capture storage technology.
  • Providing significantly more resources to protect people in Africa and Asia at risk from global warming impacts.
  • Requiring all emitters to purchase allowances that allow them to emit greenhouse gases.

These additions will significantly speed reductions, and help protect people most at risk.

The southern California wildfires will take an enormous human and financial toll. To reduce the likelihood of future similar disasters, we must reduce the carbon pollution that causes global warming. The faster the reductions, the less risk from higher temperatures, drought and more wildfires.

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Daniel J. Weiss

Senior Fellow