Are the sizzling heat and unheard-of storms Americans are suffering through this summer the result of long-term climate change? Probably. Should Utahns expect the horrific wildfires and drought to continue unabated next summer because the warnings about climate change have gone unheeded? It's likely.
It is more than mere coincidence that scientists for decades have been predicting growing numbers of devastating wildfires, hotter summers, shorter winters and decreasing snowfall in the American West and now it's happening. The warnings of climate scientists that global warming caused, at least in part, by greenhouse-gas emissions from burning fossil fuels have not resulted in the kind of cutbacks on carbon emissions that might have curbed the warming trend.
But, then, what about last year, when Utah had cool temperatures, heavy spring snowfall and rain that brought flooding to the same areas that are now parched and burning?
Scientists have never said that such a long-term change as global warming would mean a steady, unbroken uptick in seasonal temperatures every year. Weather in the short term is affected by myriad factors. Last year's records for cool temperatures and wet spring months, and this year's sudden shift to record-setting heat with little moisture, are part of a decades-long pattern.
But, make no mistake, the trend since the beginning of the industrial revolution and its accompanying increase in burning of coal and other fossil fuels has been warmer temperatures, and that trend is expected to continue. Ice caps are melting and oceans are warming, causing more severe weather. And policy makers must shoulder the blame.
Former President George W. Bush and his energy advisers, mostly petroleum-industry advocates, ignored the warnings. Bush attorneys were told to doctor scientific reports that predicted severe weather linked to CO2 emissions.
President Obama tried in his first two years in the White House to gather support for some kind of policy to limit and reduce carbon emissions, but politicians worried about losing money from extraction industries thwarted him.
Now the course toward a hotter planet cannot be reversed, but the speed and intensity of the warming could still be tempered. While we wait for sensible policies, scientists are helping coastal communities plan for the inevitable rising seas and severe storms.
In the West, this year's wildfire season may not be duplicated next year, but summers in coming decades will look more like 2012 than 2011.