Sea ice in the Arctic continues its record decline, thanks to unusually cloud-free conditions and above-average temperatures. For August 21, the National Snow and Ice Data Center estimated that fully one third of the Arctic ice cap was missing, compared to the average levels observed on that date from 1979-2000. Sea ice extent was 4.92 million square kilometers on August 21, and the 1979-2000 average for the date was about 7.3 million square kilometers. Arctic sea ice has fallen below the record low absolute minimum of 4.92 million square kilometers set in 2005 by about 8%, with another 3-5 weeks of the melting season still remaining. Reliable records of sea ice coverage go back to 1979.
Figure 1. Extent of the polar sea ice on August 21, compared to the average for the date from the 1979-2000 period (pink line). Image credit: National Snow and Ice Data Center.
With one third of the Arctic ice cap already gone, and another month of melting to go, we need to consider what effect this will have on weather, climate, and sea level rise. Well, we don't need to worry about sea level rise, since the polar sea ice is already in the ocean, and won't appreciably change sea level when it melts. However, the remarkable melting of the ice cap will likely lead to unusual weather patterns this fall and winter. The lack of sea ice will put much more heat and moisture into the polar atmosphere, affecting the path of the jet stream and the resultant storm tracks. Expect a much-delayed arrival of winter to the Northern Hemisphere again this year, which may lead to further accelerated melting of the ice cap in future years.
Last week, I remarked that the most recent images from the North Pole webcam show plenty of melt water and rainy conditions near the Pole. It turns out that was misleading, since the webcam is on a ship that was headed towards the pole, but had not reached it. There have been rainy conditions at the Pole this summer, and there is some open water there, but this is not uncommon in summer. Shifting ice frequently opens up leads (cracks) with open sea water at the Pole. It was one of these open leads that British swimmer Lewis Gordon Pugh swam in for 18 minutes this July to draw attention to global climate change.
Figure 2. Total rainfall from August 10-22 as estimated by NASA's TRMM satellite.
Midwest flooding
To get an idea of the magnitude of the flooding that has hit the Midwestern U.S. during the past ten days, take a look at the total amount of rain from August 10-22 (Figure 2). We can blame Tropical Storm Erin for the rain in Texas and Oklahoma (up to 11 inches), and for the nine flooding deaths that occurred in those states. However, the unbelievable rain amounts in excess of 20 inches in Minnesota and Wisconsin were primarily due to a frontal system--with the help of some copious moisture pumped northwards by the counter-clockwise circulation around Erin while it spun over Oklahoma.
Tropical update
There are no threat areas in the Atlantic to discuss. Two of our four reliable forecast models, the NOGAPS and ECMWF, are predicting that a tropical depression could form off the coast of Nicaragua on Sunday. The models forecast that this system would move inland over Nicaragua and Honduras by Monday.
I'll have an update on Saturday morning.
Jeff Masters
Bulldozer trying to clear sand and debris from Norman Manley Highway(Airport Road)
The flood is over, now the cleanup
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Nevermind...I found the 'Weather Stickers' on WU =)
Also, in the south, Greenland is acutally green in the summer, and probably would have been more so in the Vikings time.
We need a vigorous wave or SFC ow to watch, because this GW discussion is a beating.
Like watching water wiggle.
i put you down has a no vote for now be come i was not sure what your vote was
"I remarked that the most recent images from the North Pole webcam show plenty of melt water and rainy conditions near the Pole. It turns out that was misleading, since the webcam is on a ship that was headed towards the pole, but had not reached it."
Umm, that's not misleading, that's just plain wrong. If a non-global-warming person had posted a picture of massive ice from Antarctica and claimed it was the North Pole, you'd be crying foul.
Yes, it was wrong...but he corrected his statement. I remember looking at the photos and thinking they didnt seem stationary...but then I realized I didnt know anything about the North Pole and didnt question. At least he came out and told the truth, which some people never do.
Oh, and as for Antarctic ice, no statistical significant change in the ice has been found to this point. As said earlier, we do not have a long enough record to truely make a statement about it. All we do know is that has increased recently.
I dont even live near the coast.. hell my home sits at 1443 feet above sealevel... yet I have GO bags, well bins, already set for my family and I even included the pets in those bins.
NOAA radios.. one in each room, including bathroom, plus one in each vehicle.
I am one of the few folks that does it right, yes there are many many out there that do the same but looking at the whole picture we are the small minority.
Just like folks should have at least a flashlight and a multi tool in their cars instead of the cell to call AAA.
Also, DallasGumby - you got WUmail.
My personal GO bag in my truck even has a gas mask in it because I work in an industrial area with alot of toxic chemicals.
The coast has a greenish cast to it in the summer time - Lichen growing on the rocks.
In 1983, while on a research cruise in Antarctica, one of the projects was measurements of currents, salinity and Temp of the waters under the Ross Iceshelf. The lead Researcher Mr. Stanley S. Jacobs (Doherty Senior Research Scientist - LDEO-Ocean and Climate Physics - Earth Institute Affiliate: Lamont-Doherty Earth Observatory (LDEO) and I were talking about Ice melt. I remember the conversation because he made a statement that astounded me. He asked if I knew how long it took for the North American Ice coverage took to retreat from its greatest extent during the last Ice Age to about where it was in Canada in 1983. I guessed several 100 years – He smiled and said no, just about 75 years, one persons life time.
I have no data to back this up, but he had no reason to joke…
Also in 1984 and 92 or 93 the day time air temp in Jan/Feb just off the Ross Ice Shelf reach 40 deg F several times - we were outside with short sleave shirts
by the way, i didn't add astrophysicists to add credibility to what I said, though they would know more than me...but obviously not scientists studying these topics..
still learning and thank you all for information and directions to sites that help facilitate the learning....
NEAR 32N48W SW ALONG 29N57W THEN NW TO 30N61W BECOMING
STATIONARY CONTINUING ACROSS BERMUDA
well, that perks me up today!
thanks!
LOL, very vigirous.
Also, DallasGumby - you got WUmail.
Myles, back at you!
Just my .02 cents on GW-you can argue for it or against it, but I believe that we (the world) are pumping enormous amounts of toxic chemicals into the air/water/land....you just know that can't be good, so I do believe we must change our ways-look at the atmosphere-it's really a thin layer.
Almost no one on either side of the GW debate is arguing about "pumping enormous amounts of toxic chemicals". The debate is about carbon dioxide, hardly a toxic chemical.
jp it would be the same regardless. Ice even when its frozen displaces water. However it doesnt quite work that way with the icecaps themsleves.....when they melt water level rises. but in a glass it would be raised regradles. Now if you mean water level alon then it would be higher in the warm one(duh).
Where did you study physics? There might be a difference after the ice melted but it would be too small to measure with the naked eye
re: sea levels....i was told by 2 astrophysicists that the warming of the oceans will raise the levels...water expands as it warms..
"Why does water expand when it cools?
Water is peculiar. When most substances change from liquid to solid form, they shrink together, become denser, their molecules packed most closely together.
But when water changes from a sloshy liquid to solid ice, it expands, becomes less dense. Which is why ice floats to the top of your Coke, rather than sinking like a stone to the bottom.
At normal atmospheric pressure, molecules usually behave in predictable ways as their temperature changes. Molecules fly apart into a gas when heated, condense into a flowing liquid when cooled, and shrink into a frozen solid when chilled still further. The changes in state parallel changes in energy: from high energy to medium energy to barely jiggling."
austxanne, this is not a flame at you, but who are these two astrophysicist....exactly ???
Does this mean water expands when it warmed and expands when it cooled ??? How do it know ???
This then will finally solve and put to rest todays quandary of GW/Artic melting and flooding vs Antarctic ice expansion .
The answer.....it doesn't matter. Either way we're doomed. I...I...I g.g.g.guess. hmmmm.. Maybe some "scientist" here can clarify it for us. Too much for my little brain.
National Weather Service Denver Colorado
257 am MDT Friday Aug 23 2007
by Monday afternoon. Ridging aloft then rebuilds
westward across the Great Basin...resulting in a northwest flow pattern and
opening The Gates to more cooling from the north by the middle of
next week. Latest GFS showing decent front moving into eastern Colorado early
Wednesday with more noticeable cooling and chance of precipitation. Current grids
already refelct this so no changes needed on the out periods.
Area forecast discussion
National Weather Service Pueblo Colorado
355 am MDT Friday Aug 24 2007
GFS continues to indicated a substantial cold
front dropping south across the plains Tuesday night/Wed...with moist
upslope through 700 mb developing by Wednesday afternoon...along with
much cooler temperatures. Current grids have this scenario well
covered...with only minor adjustments made.
i dont no if this will play out right but if it dos this could shut down the gulf for any Tropical Weather Activity
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