Seasons Arriving, On Average, Two Days Earlier Than Normal, Along With Peak Hot & Cold Days - Nature

[hatrack]

WASHINGTON (Reuters) - Looking forward to spring? The good news is that it is coming two days earlier on average, but so are summer, autumn and winter, researchers said on Wednesday. They found that on average, the hottest day of the year in temperate regions has moved forward by just under two days, and so has the coldest day of the year.

While the consequences of this shift are not clear, it is worrying, Alexander Stine of the University of California, Berkeley and colleagues said. "All of the seasons are coming earlier. They are both hotter and they are earlier," Stine said in a telephone interview.

The effect can be seen in both the northern and southern hemispheres, said Stine, whose team studied more than 100 years of temperature data to tease out the pattern. Writing in the journal Nature, Stine and colleagues said the effect is related to global warming and is very likely to be caused by humans. The shift in seasons is unsettling because none of the climate change computer models predict this, Stine said.

EDIT

This pattern suggests the planet has lost something that helps draw out the process. "The land is putting up less resistance to what the sun is telling it to do," Stine said. There may be a loss of moisture in the soil, or some other factor like pollution, he said. "If the way the Earth is responding to the sun is changing, we'd like to know that," Stine said. "There is a concern that we may be missing some important processes."

EDIT

http://www.reuters.com/article/environmentNews/idUSTRE50K6JC20090121?feedType=RSS&feedName=environmentNews

[amitten]

1. But at last, Obama's here to help. I do believe it will usher in a

new era of worldwide compliance with updated emissions rules.

Time will tell.

[hatrack]

3. I'd like to think so myself, but in the immortal words of Corporal Hudson . . .

"I dunno man, this is a big fucking signal!"

[amitten]

5. There have been big signals for the last twenty years, ignored.

Yes, it does make one panic.

But let's just look ahead to the work that will now surely get done. It won't get done in time to restore the normalcy we grew up with. But it will get done in time to stop major worldwide devastation. It's the best we can hope for now.

[Orrex]

2. I blame Daylight Savings

Damn you, Ben Franklin! Damn you!

[LiberalEsto]

4. My allergies are arriving sooner

It used to be that my tree pollen allergies wouldn't start acting up until early February.
Today is January 22, and I'm already wheezing.

[OKIsItJustMe]

6. University Press Release-"…the shift appears to be related, …, to a particular pattern of winds…"

http://www.berkeley.edu/news/media/releases/2009/01/21_seasons.shtml

Summer peak, winter low temperatures now arrive 2 days earlier

By Robert Sanders, Media Relations | 21 January 2009

BERKELEY — Not only has the average global temperature increased in the past 50 years, but the hottest day of the year has shifted nearly two days earlier, according to a new study by scientists from the University of California, Berkeley, and Harvard University.

Just as human-generated greenhouse gases appear to the be the cause of global warming, human activity may also be the cause of the shift in the cycle of seasons, according to Alexander R. Stine, a graduate student in UC Berkeley's Department of Earth and Planetary Science and first author of the report.

"We see 100 years where there is a very natural pattern of variability, and then we see a large departure from that pattern at the same time as global mean temperatures start increasing, which makes us suspect that there's a human role here," he said.

Although the cause of this seasonal shift - which has occurred over land, but not the ocean - is unclear, the researchers say the shift appears to be related, in part, to a particular pattern of winds that also has been changing over the same time period. This pattern of atmospheric circulation, known as the Northern Annular Mode, is the most important wind pattern for controlling why one winter in the Northern Hemisphere is different from another. The researchers found that the mode also is important in controlling the arrival of the seasons each year.

…