Many parts of the US experienced scorching temperatures over the past six months, so it may come as no surprise that the first half of 2012 was the warmest on record. The National Oceanic and Atmospheric Administration’s (NOAA) State of the Climate Report, published on July 9 found that not only did the last two weeks of June alone see “170 all-time high temperature records broken or tied,” but the first half of 2012 was the warmest January-June period for the Lower 48 States since records began in 1895.
The report also revealed that a total of 28 states, all east of the Rocky Mountains, also had a record warm first six months of the year. Another 15 states had their top 10 warmest for the months January-June. Interestingly, only Washington state recorded a cooler-than-average first half of 2012.
These record-breaking temperatures have brought about speculation over the role of global warming. Andrew Freedman, writing for Climate Central expressed that while the heat wave is certainly historic and record breaking, it is perhaps not unprecedented. Freedman notes that current warming trends could make heat waves such as this more common in the future: “it’s reasonable to think that while a record-breaking heat wave used to require a massive, unusually powerful dome of high pressure in order to occur, now the same record could be set with a weaker weather system.”
Many other scientists have come out in agreement that this heatwave is more than just “summer,” as some have tried to claim. Speaking to The Guardianwith Kevin Trenberth of the National Center for Atmospheric Research in Colorado “We are certainly seeing climate change in action,” he said. “This year has been exceptionally unusual throughout the United States.”
While June has seen record temperatures in New York, it is actually only the 14th warmest on record for the Lower 48 States in 118 years of records. However Colorado has recorded its record hottest June, while claims that all-time state records have been set in South Carolina (113) and Georgia (112) are currently under review by the U.S. State Climate Extremes Committee.
The increased heat has also seen an expansion of the drought in the nation’s heartland. In fact, January-June 2012 was among the top 10 driest such periods on record in 14 states, primarily in the Plains states, with Delaware recording the driest period. Of course, the heat has lead to Wyoming, Colorado and Utah recording the driest months in June with the dry conditions leading to wildfires.
It wasn’t all heat however—Minnesota, Oregon, and Washington had one of their top 10 wettest January-June periods on record in 2012. However NOAA’s report is alarming if 47 of the 48 contiguous states are warmer than average over the past 12-month period (apart from Washington).