2012 shaping up to be hottest on record in US

The first six months of this year have been the hottest in the mainland United States since temperature records began in 1895. What's causing the unprecedented heat?

|
Seth Perlman/AP
Corn crops show signs of stress Friday in in Farmingdale, Ill., as they struggle to grow during a record breaking heat wave with dry weather conditions that is across most of the country Friday.

June weather records are in, and the nation's unprecedented warm spell continues, making this the warmest first half of the year and the warmest 12-month period since record-keeping began for the continental U.S. in 1895. 

Last month, like many before it, had heat that was above average, and high temperatures during the second half of June broke or tied records in 173 locations, while no record cools were reported, according to the National Climatic Data Center (NCDC).

Overall, the nation is experiencing its 10th-driest June on record, but the reality of precipitation varied from region to region, the NCDC reported, noting that the Intermountain West saw record or near-record dryness, while Florida received record precipitation thanks to Tropical Storm Debby.

Unusually high temperatures and lack of precipitation created ideal conditions for wildfires across the Rockies. Nationwide, wildfires burned 1.3 milion acres (526,000 hectares) last month. [Extreme Weather: Quiz Yourself]

Driven by unusual warmth in the eastern two-thirds of the lower 48 states, the United States has seen a series of records or near-records this year. Global average temperatures, also tracked by NCDC, are also up.     

Of course, these records are based on averages, so certain areas, such as the Pacific Northwest, have seen lower-than-average temperatures. 

July started off with a bang, breaking or tying high-temperature records in 145 locations in the continental United States, according to NCDC data as of today (July 9). The intense heat that kicked off the summer of 2012 is the result of a "blocking" pattern that has caused the jet stream, a band of high-altitude westerly winds, to trap heat above the Midwest and Southeast, Jeff Weber, a scientist with the University Corporation for Atmospheric Research in Boulder, Colo., told OurAmazingPlanet earlier this month.   

Likewise, the configuration of the jet stream kept warm air bottled up in the high latitudes during the winter, resulting in an unusually mild winter for many of the lower 48 states.

Because fluctuations in weather are natural, climate scientists are loath to attribute a single, extreme event, or even weather patterns over the course of a year, to human-caused climate change. However, the unusual warmth so far this year has not come out of the blue. Weather records clearly show that the world is warming up. The first decade of the 21st century was the warmest on record, according to the U.S. National Oceanic and Atmospheric Administration's State of Climate in 2010 report.

Follow Wynne Parry on Twitter @Wynne_Parry or LiveScience @livescience. We're also on Facebook & Google+.

Copyright 2012 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

You've read  of  free articles. Subscribe to continue.
Real news can be honest, hopeful, credible, constructive.
What is the Monitor difference? Tackling the tough headlines – with humanity. Listening to sources – with respect. Seeing the story that others are missing by reporting what so often gets overlooked: the values that connect us. That’s Monitor reporting – news that changes how you see the world.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to CSMonitor.com.

QR Code to 2012 shaping up to be hottest on record in US
Read this article in
https://www.csmonitor.com/Science/2012/0710/2012-shaping-up-to-be-hottest-on-record-in-US
QR Code to Subscription page
Start your subscription today
https://www.csmonitor.com/subscribe