Thursday, September 13, 2012

Climate change news update

If it seemed like this summer was crazy hot, that's because it was.  The national climatic data center has the scorecard.

For the U.S., summer 2012 was third-hottest in history

Meanwhile, the past 12 months (September 2011-August 2012) are the warmest 12 months ever recorded for the contiguous United States.

According the National Climatic Data Center, summer 2012 was the third-warmest overall for the contiguous United States since record-keeping began in 1895. June 2012 was the 14th warmest June on record. July was the warmest month recorded (not just the warmest July) since record-keeping began in 1895. And August ended up being the 16th warmest August on record. Above-average temperatures have been the main story line for the contiguous United States for 2012. In fact, 2012 is the warmest on record for the year-to-date period of January – August. During the eight-month period, 33 states were record warm and an additional 12 states were top-10 warm. Meanwhile, the past 12 months (September 2011-August 2012) are the warmest 12 months ever recorded for the contiguous United States.

Weather events for August 2012. Image Credit: NCDC


August provided an average temperature of 74.4 degrees Fahrenheit, which was 1.6°F above the 20th century average, marking this August the 16th warmest August in a period of record that dates back to 1895. The Central U.S., Ohio Valley, and the U.S. Southeast regions of the contiguous United States experienced at or below-average temperatures for the month of August. According to the NCDC, 4,200 daily warm temperature records broken or tied during August, and just over 2,000 daily cool temperature records broken or tied.

In general, the western United States experienced hot and dry conditions that helped fuel wildfires throughout the region. Nearly 3.6 million acres burned nationwide, and acreage burned was nearly twice the August average and the most in the 12-year period of record.
The heat and low precipitation has pushed our average temperatures from June through August to become the third-hottest summer on record for the contiguous United States with an average temperature of 4.4°F, or 2.3°F above the 20th century average. Only the summers of 2011 (74.5°F) and 1936 (74.6°F) had higher temperatures for the Lower 48. Finally, September 2011-August 2012 period was the warmest such 12-month period on record for the contiguous U.S., with an average temperature of 56.0°F, 3.2°F above average.

June through August 2012 average temperatures in 2012 compared to normal. The extreme west coast and southeast United States experienced below-normal temperatures. Image Credit: NCDC/NOAA
When you look at the average temperatures for every August in the contiguous United States since record keeping began back in 1895, you can see a very obvious trend. The overall temperatures are slowly getting warmer throughout each decade. It is important never to focus on a particular region within the U.S. when it comes to looking at climate trends. You will see spikes of above and below average temperatures in parts of the Southeast/Pacific Northwest. Climate looks at a much bigger picture – such as the whole United States, or the entire Northern or Southern Hemisphere. In general, warming continues as the dominant climate story on Earth today. more
I happen to like this story because Paul Douglas is a local weatherman who happens to be very good at what he does.  Here in Minnesota where the weather tries to kill you at least once a year, this is no small matter.  A few months back, Douglas wrote some comments directed at his Republican buds chastising them for their crazy climate denial.  Not surprisingly, the denialist crowd just howled with rage.  So this time, he is trying a Top Ten list.  His whole post is linked below but here is the list.  Good luck Paul.  You're going to need it.

Paul Douglas's Top Ten Reasons to Accept Reality on the Climate

Here's my Top Ten Reasons Why This Isn't Business as Usual for the Climate - things that convince me -- and should convince you too.

10). Shifting Weather Patterns - The jet stream is shifting north over time. I'm seeing things on the weather maps every other day that can't be explained away as "normal extremes".

9). Rising Sea Levels - whatever your skeptical uncle Joe says, seas are warming, and as they warm, they expand and sea level goes up. Most scientists predict 3-4 feet in the next 80 years or so. Think twice about buying that retirement condo right on the beach. Find something 4 blocks inland, and be patient.

8). Warmer, More Acidic Oceans - if you scuba dive, you've probably noticed that corals reefs aren't what they used to be. That's ocean acidification from absorbing carbon dioxide. It's radically changing the ocean ecosystems and fisheries right now.

7). Straining Water Resources - water for drinking, "fracking", farming, ethanol production, soda pop, or energy generation - whatever your flavor, it's getting scarcer. That affects all of the above.

6). Dying Forests - not just by massive, historic wildfires, but by pests like the pine beetle that no longer gets killed off in the warmer winters, turning entire rocky mountains brown with dead pine trees.

5). Extreme Rains and More Severe Local Storms. 4-5% increase in atmospheric moisture - warmer air holds more moisture. That means it gets drier on the ground because more is absorbed by the atmosphere. But it also means when it rains, it rains harder as that higher water content rains out. But dry soil and heavy rains equal floods, and that means more damage and more water lost to runoff.

4). Spike in Wildfires - less water plus pine beetles and other crawly critters that kill trees plus drier soil means more wildfires.

3). More Drought -- more water in the atmosphere means less on earth and thus more drought.

2). Superheated summers -- the above combine to create hot, hot, hot summers. Drier air is hotter without water to moderate it. Hotter air absorbs even more, even quicker. And hotter air means more air conditioners, means more carbon going back into the atmosphere.

And the number one reason:

Arctic Sea Ice Monitor. The latest value: 3,593,750 square kilometers on September 9, 2012. A new record minimum of Arctic sea ice extent was set on August 24, 2012. The four lowest values of Arctic sea ice have been observed since 2007. Source: Japan Aerospace Exploration Agency, Earth Observation Research Center.

1). Record Arctic Ice Loss. As I said, less ice reflecting means more water absorbing. We used to say the Arctic might be ice free by the middle of the century. Now scientists are saying it may happen as early as 2015. That's in three years, people. The ice is melting this year at an unprecedented rate, and if we have another warm winter, it won't be replenished. This could tip the scales for a lot of larger climate changes to come. A comprehensive article in the Wall Street Journal on September 7 summarized "...the six lowest Arctic sea ice levels on record all occurred in the past six years." more

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