One of the natural disasters that affects the Western U.S. is, of course, wildfires. I hope most readers know by now that our 20th century forest management policies had negative impacts on overall forest health. Today’s forests are too overgrown – an unhealthy condition for the focus of this post: climate change.
I further hope that most readers know that climate change has already had some deleterious effects on Western forests, among them massive die-offspine beetle infestations. Those effects aren’t likely to slow down any time soon. Indeed, a recent paper, “Impacts of climate change from 2000 to 2050 on wildfire activity and carbonaceous aerosol concentrations in the western United States” finds an amazing increase in wildfire activity Western U.S. by 2050 under a moderate warming scenario:
We show that increases in temperature cause annual mean area burned in the western United States to increase by 54% by the 2050s relative to the present-day … with the forests of the Pacific Northwest and Rocky Mountains experiencing the greatest increases of 78% and 175% respectively. Increased area burned results in near doubling of wildfire carbonaceous aerosol emissions by mid-century.
Fellow Coloradans: that 175% increase is going to happen in our backyard.
I’m going to highlight what I consider to be the most important point of this result: these results arise from a moderate warming scenario. By that, I mean this forecast is associated with the IPCC’s A1B scenario, which includes CO2 concentrations at 552ppm in 2050, and which predicts “mean July temperatures to increase by 1.8°C from 2000 to 2050.” Since the IPCC’s Fourth Assessment Report was issued in 2007, observations have confirmed that we are currently on the worst-case emissions path, known as A1F1 (see the Wiki link for more information). Unfortunately, a lot of research is being conducted on the A1B scenario and not the A1F1 scenario. Being on the worst-case scenario track cannot mean anything good for the Rocky Mountain forests, that much is certain.
This study confirms that another positive-feedback loop could be establishing itself. Climate change is warming up and drying out the region. This increases the chances that forests will experience more frequent and longer burning fires. Those fires release additional huge amounts of carbon dioxide, which ensures that the already warmed climate will stay warmer longer as well as increasing warming. The acceleration of climate change that stoked longer-lived and more frequent wildfires is accelerated even further.
Since I try to combine science with politics in my posts, this is the place to point out that Rep. John Salazar, whose district covers a lot of the area cited in the study, voted against ACES in June. The same John Salazar who is working against health care reform because “it costs too much” and isn’t “deficit-neutral” voted to subject the Western U.S. to burn areas 5 times as large as they are today. Where will the money come from to fight those fires and protect people in the future, Rep. Salazar? Since you’re so anti-investment, what program would you propose we cut to pay for firefighting efforts in 2050 when 35,000,000 acres burn every year instead of 7,000,000?
The good news is the House passed H.R. 2454 and is awaiting Senate approval of their version. Climate change mitigation at this point in time pays for itself. That might not always be the case.
Cross-posted at SquareState.