Thanks to Luke Walker for alerting us to this story. Luke asks if this is controversial fiddling or good science?
Graphic courtesy of NOAA
GREENHOUSE GASES LIKELY DROVE NEAR-RECORD U.S. WARMTH IN 2006
Greenhouse gases likely accounted for more than half of the widespread warmth across the continental United States last year, according to a new study by four scientists at NOAA’s Earth System Research Lab in Boulder, Colo. Last year’s average temperature was the second highest since record-keeping began in 1895. The team found that it was very unlikely that the 2006 El Niño played any role, though other natural factors likely contributed to the unusual warmth. The findings will appear September 5 in the Geophysical Research Letters, a publication of the American Geophysical Union.
The NOAA team also found that the probability of U.S. temperatures breaking a record in 2006 had increased 15-fold compared to pre-industrial times because of greenhouse gas increases in Earth’s atmosphere.
Preliminary data available last January led NOAA to place 2006 as the warmest year on record. In May, NOAA changed the 2006 ranking to second warmest after updated statistics showed the year was 0.08 degree F cooler than 1998.
The annual average temperature in 2006 was 2.1 degrees F above the 20th Century average and marked the ninth consecutive year of above-normal U.S. temperatures. Each of the contiguous 48 states reported above-normal annual temperatures and, for the majority of states, 2006 ranked among the 10 hottest years since 1895.
“We wanted to find out whether it was pure coincidence that the two warmest years on record both coincided with El Niño events,” says lead author Martin Hoerling of NOAA/ESRL. “We decided to quantify the impact of El Niño and compare it to the human influence on temperatures through greenhouse gases.” El Niño is a warming of the surface of the east tropical Pacific Ocean.
Using data from 10 past El Niño events observed since 1965, the authors examined the impact of El Niño on average annual U.S. surface temperatures. They found a slight cooling across the country. To overcome uncertainties inherent in the data analysis, the team also studied the El Niño influence using two atmospheric climate models. The scientists conducted two sets of 50-year simulations of U.S. climate, with and without the influence of El Niño sea-surface warming. They again found a slight cooling across the nation when El Niño was present.
To assess the role of greenhouse gases in the 2006 warmth, the NOAA team analyzed 42 simulations of Earth’s climate from 18 climate models provided for the latest assessment by the Intergovernmental Panel on Climate Change. The models included greenhouse gas emissions and airborne particles in Earth’s atmosphere since the late 19th century and computed their influence on average temperatures through 2006. The results of the analysis showed that greenhouse gases produced warmth over the entire United States in the model projections, much like the warming pattern that was observed last year across the country.
For a final check, the scientists compared the observed 2006 pattern of abnormal surface temperatures to the projected effects of greenhouse-gas warming and El Niño temperature responses. The U.S. temperature pattern of widespread warming was completely inconsistent with the pattern expected from El Niño, but it closely matched the expected effects of greenhouse warming.
When average annual temperature in the United States broke records in 1998, a powerful El Niño was affecting climate around the globe. Scientists widely attributed the unusual warmth in the United States to the influence of the ongoing El Niño.
“That attribution was not confirmed at the time,” says Hoerling. “Now we have the capability, on the spatial scale of the United States, to better distinguish natural climate variations from climate changes caused by humans.”
The authors also estimate that there is a 16 percent chance that 2007 will bring record-breaking warmth.
CNN’s take on the story is here:
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
New Scientist is also running it:
http://www.newscientist.com/blog/environment/2007/08/el-nio-not-responsible-for-us-heatwave.html
El Nino not responsible for US heatwave
This is hot off the presses – a new study shows that human emissions of greenhouse gases made it 15 times more likely that the US would see record-breaking temperatures in 2006.
In the event, temperatures were not the hottest, but the second-hottest since records began in 1895. The hottest year ever was 1998, which was also marked by a powerful El Niño. Scientists have widely attributed the record-breaking temperatures to El Niño.
So when data revealed that 2006, also an El Niño year, was the second-warmest year ever, Martin Hoerling at NOAA in Colorado and his colleagues decided it was time to find out if this was mere coincidence, or if El Niño was responsible for the warmth.
Looking at data from 10 El Niño events since 1965, they found that El Niño tends to cool US temperatures slightly – not warm them. CONTINUES .. ..
That explains the mass exodus of “Okies” here in California. Cause when they get that record heat on the panhandle peoples just got to move.(sarcasm)
{Note – Although in 1934 my grandmother Bessie and her husband Jed were in reality, [not the make believe statistics of the NOAA], forced to bundle up my mother and aunts and make the trek to Califoria – driven out by a decade of drought and dust storms.}
Other notable events of 2006:
25,700 deaths in the UK (must have been the fever)
http://www.guardian.co.uk/medicine/story/0,,1933677,00.html
Al Gore visits Australia.
http://motls.blogspot.com/2006/11/record-cold-in-australia.html
70% fewer hurricanes despite NOAA warming and el Nino
http://motls.blogspot.com/2006/12/weak-2006-hurricane-season.html
I live in the southeastern U.S. Decades ago, the radio stations would have contests to predict when the temperature would first hit 100° F. Then years and years went by when it never went that high, so the contests stopped. Now, this year, for the first time in ages, it did reach 100 and did so for nine straight days. Does that prove global warming? If it does, someone needs to explain the intervening cooler decades. I’m sure that global warming is responsible for global cooling, too, as those folks have to have a no-lose situation.
What a beat up. NOAA picks a warm year and gives us a graphic showing above normal temperatures. Gosh, what else would the damned thing show?
What we don’t see is the map showing those parts of the USA that had the highest mean annual temp on record. And then how about showing the 1934 map so we can compare the two?
He hasn’t read it. Comments on the analysis = 0.0
Exerpt from The Worst Hard Time by Timothy Egan
Pg 150-152
On, May 9, 1934, a flock of whirlwinds started up in the northern prairies, in the Dakotas and eastern Montana, where people had fled the homesteads two decades earlier. The sun at midmorning turned orange and looked swollen. The sky seemed as if it were matted by a window screen.
The next day, a mass of dust-filled clouds marched east, picking up strength as they found the jet stream winds, moving toward the population centers. By the time this black front hit Illinois and Ohio, the formations had merged into what looked to pilots like a solid block of airborne dirt. Planes had to fly fifteen thousand feet to get above it, and when they finally topped out at their ceiling, the pilots described the storm in apocalyptic terms. Carrying three tons of dust for every American alive, the formation moved over the Midwest. It covered Chicago at night, dumping an estimated six thousand tons, the dust slinking down walls as if every home and every office had sprung a leak. By morning, the dust fell like snow over Boston and Scranton, and then New York slipped under partial darkness. Now the storm was measured at 1,800 miles wide, a great rectangle of dust from the Great Plains to the Atlantic, weighing 350 million tons. In Manhattan, streeetlights came on at midday and cars used their headlights to drive. A sunny day, which had dawned cloudless, fell under a haze like that of a partial eclipse. From the observatory at the top if the Empire State Building, people looked into a soup unlike anything ever seen in midtown. They could not see the city below or Central Park to the north. An off-white film covered the ledge. People coughed, rushed into hospitals and doctors, offices asking for emergency help to clear their eyes. The harbor turned gray, the dust floating on the surface. The grass of the parks and the tulips rising to break the Depression fog were coated in fine sand. From Governors Island, visibility was so bad a person could not see the boats just beyond the shore. Baseball players said they had trouble tracking fly balls.
Reporters rushed out to query the experts. “I spent my youth in the south, where such occurrences are more common, but I didn’t remember one in which the dust was carried so high,” said a New York meteorologist, Dr. James H. Scarr. “I can’t say I like this air. It cuts off all my free breathing.”
The pyrheliometer, an odd-looking instrument that resembled something vaguely futuristic with an art deco touch, measured sunlight at 50 percent — that is, only half the ultraviolet rays of a normal sunny spring day made it to the city.
New York was a dirty city in 1934, the air clogged with auto exhaust and the effluents of thousands of small shops, factories, bakeries, and apartments. The air could be so hazardous that people with respitory problems were advised to move out to the Western desert for life. On a typical day, the dust measured 227 particles per square millimeter — not a good reading for someone with health problems. But on May 11, the dust measured 619 particles per square millimeter. It got inside as well. In the NBC radio studios, air filters were changed hourly. A professor from New York University, Dr. E. E. Free, calculated that on the seventeenth floor of the Flatiron Building on Fifth Avenue, the thickness of the dust was about forty tons per cubic mile, which meant all of New York City was under the weight of 1,320 tons.
New Yorkers did not like this monstrous visitor from the heartland. They had heard reports about blowing homesteads and had seen a few newsreels, but it was a world away, far beyond the Hudson River. On May 11, the orphaned land of the Great Plains came to the doorstep of the nation’s premier city. For five hours, the cloud dumped dirt over New York. Commerce came to a standstill. The captain of a cargo ship, the Deutschland, delayed coming into anchor because he was not sure what had happened. The outline of the Statue of Liberty was barely visible, and it wore a coat of light gray topsoil. The Deuschland’s skipper said it reminded him of the Cape Verde Islands, where the sands of the Sahara blew out to sea.
“HUGE DUST CLOUD BLOWS 1,500 MILES, DIMS CITY 5 HOURS”
That was the New York Times headline the next day. The paper called it “the greatest dust storm in United States history.”
So you were saying 2006 was warmer then 1998?
Or was it cooler?
Whatever.
I think I get it now.
When 1934 is declared the hottest year on record in the USA, one must remember that the United States are only a small part of the earth surface area.
But when 2006 is declared the second hottest (to 1998) in the USA, this is a reliable indication of a global trend.
Attributing more than half the USA warmth to “other natural factors”, of course, is left up to computer models provided by the IPCC.