This past week much of the eastern United States sweltered under a record-breaking heat wave that left at least seven people dead. From the Northeast to the South, the heat cast a pall over outdoor activities and sent hundreds flocking to cooling centers. In some eastern states high temperatures complicated tornado cleanup efforts and compounded the misery of tornado survivors whose air-conditioned homes were destroyed.
By Thursday meteorologists were predicting cooler temperatures would arrive soon in some affected areas, especially in the Northeast. However people over much of US can expect to see more and more serious heat waves during the summers of the future. Climate change is predicted by scientists to result in hotter summers, especially in the eastern half of the US, as global wind and temperature patterns shift and carbon emissions from the burning of fossil fuels magnify the natural ability of the atmosphere to trap and retain heat.
Last year a study published by Stanford researchers the scientific journal Geophysical Research Letters predicted climate change will lead to an increase in serious and lethal heat waves in the United States over the next thirty years. Of course that doesn’t mean every summer will set new temperature records in every part of the country. It also doesn’t preclude the likely possibility that some parts of North America will actually see cooler, rainier summers due to shifts in weather patterns caused by climate change. But it does mean that, over time, heat waves like last week’s will become less of an exception and more the summer norm in much of the United States.
The frequency of US heat waves has already gone up since the 1970s, and last summer was itself a record-breaker for the eastern part of the country. By the end of June of 2010, heat waves had already shattered records in cities like Washington, DC, raising questions about whether global warming had something to do with the unusual weather. The United States was hardly alone: 2010 also saw major heat events throughout Europe, Asia, and other parts of the world including a heat wave in Russia that sparked massive wildfires unlike any seen in living memory.
Though it’s too early to tell for sure, this summer appears poised to bring record-setting heat to the eastern United States once more. While for many this is an inconvenience, for others it could be a matter of life and death. In fact heat is the leading cause of weather-related death in the US, trumping other weather events that often receive more media attention. In an average year, heat kills more people in the US than hurricanes, tornadoes, floods, and lightning storms put together. Nationally over 1,500 people die due to excessive heat every year.
The US Environmental Protection Agency (EPA) has declared increased frequency of heat waves to be one of the main threats posed by climate change. In 2009 the agency officially found greenhouse gases that cause climate change to be a threat to human health. Since then the EPA has begun moving to regulate greenhouse emissions from major polluters, following its obligation under the Clean Air Act to curb pollutants that harm the health of people.
Yet because the sources of greenhouse emissions are so pervasive in the economy, existing Clean Air Act regulations will likely not be enough to make a major dent in the problem. To really stop climate change, along with associated threats like major heat waves, Congress will most likely have to pass a new law designed to spur a rapid transition to clean energy sources. In the midst of last summer’s heat lawmakers declined to do just this, with the US Senate deciding not to even vote on a bill that would have triggered modest steps to reduce carbon emissions.
This year Congress is even less likely to pass climate change legislation, after electoral gains won by Republicans last November. The more conservative wing of the Republican Party has made denying the existence of climate change a central tenant of its ideology. Many members, like Oklahoma Senator James Inhofe, contend the idea of climate change is a conspiracy hatched by scientists bent on restricting freedoms and ruling the world.
Meanwhile across the eastern US, dozens of cities are feeling the very real impacts of climate change caused by human activity—in some cases with deadly consequences. The past week’s heat wave is a reminder of what kind of weather millions of US residents can expect to see more of if climate change is allowed to continue unchecked.
Photo credit: flickr.com/photos/kenner116/907898818/