Polar ice cap gone by 2030?
July's huge drop in Arctic sea ice extent continued into August 2007, according to figures released this week by the National Snow and Ice Data Center. August 2007 sea ice extent plunged 31% compared to the average from 1979-2000. As of September 4, 2007, the sea ice extent was a full 17% below the record minimum that occurred on September 20-21, 2005. Although the rate of melting is starting to slow down as the days grow shorter, more melting is expected this month.

The difference in sea ice extent between August 1979 (the beginning of the data record) and August 2007 was a startling 37%. University of Illinois Polar Research Group presented similar estimates this week. They measure sea ice area--not extent. Sea ice area does not include all the long, narrow cracks in the ice, and so the numbers for sea ice area are different (lower) than for sea ice extent. Their sea ice area estimate for September 5, 2007 (Figure 1) was 42% less than for the same date 28 years ago.



Figure 1. Comparison of sea ice area on September 5, 1979 and September 5, 2007. Sea ice area in early September has declined 42% in the 28 years since 1979. Image credit: University of Illinois Polar Research Group.

An ice-free Arctic in just 23 years?
None of our computer climate models predicted that such a huge loss in Arctic ice would occur so soon. Up until this year, the prevailing view among climate scientists was that an ice-free Arctic ocean would occur in the 2070-2100 time frame. The official word on climate change, the February 2007 report from the U.N.-sponsored Intergovernmental Panel on Climate Change (IPCC), warned that without drastic changes in greenhouse gas emissions, Arctic sea ice will "almost entirely" disappear by the end of the century. This projection is now being radically revised. Earlier this year, I blogged about a new study that predicted abrupt losses of Arctic sea ice were possible as early as 2015, and that we could see an ice-free Arctic Ocean as early as 2040. Well, the Arctic Ocean has suffered one of the abrupt losses this study warned about--eight years earlier than this most radical study suggested. It is highly probable that a complete loss of summer Arctic sea ice will occur far earlier than any scientist or computer model predicted. In an interview published yesterday in The Guardian Dr. Mark Serreze, and Arctic ice expert with the National Snow and Ice Data Center, said: "If you asked me a couple of years ago when the Arctic could lose all of its ice, then I would have said 2100, or 2070 maybe. But now I think that 2030 is a reasonable estimate. It seems that the Arctic is going to be a very different place within our lifetimes, and certainly within our children's lifetimes." While natural fluctuations in wind and ocean circulation are partly to blame for this loss of sea ice, human-caused global warming is primarily to blame. In the words of Dr. Serreze: "The rules are starting to change and what's changing the rules is the input of greenhouse gases. This year puts the exclamation mark on a series of record lows that tell us something is happening."

The implications

The melting of the Arctic sea ice will not raise ocean levels appreciably, since the ice is made up of frozen sea water that is floating in the ocean. Sea ice melt does contribute slightly to sea level rise, since the fresh melt water is less dense than the salty ocean water it displaces. According to Robert Grumbine's sea level FAQ, if all the world's sea ice melted, it would contribute to about 4 millimeters of global sea level rise. This is a tiny figure compared to the 20 feet of sea level rise locked up in the ice of the Greenland ice sheet, which is on land.

The biggest concern about Arctic sea ice loss is the warmer average temperatures it will bring to the Arctic in coming years. Instead of white, reflective ice, we will now have dark, sunlight-absorbing water at the pole, leading to a large increase in average temperature. Warmer temperatures will accelerate the melting of the Greenland ice sheet, which holds enough water to raise sea level 20 feet. The official word on climate, the 2007 IPCC report, predicted only a 0.6-1.9 foot sea level rise by 2100, due to melting of the Greenland ice sheet and other factors. I believe these estimates will need to be revised sharply upwards in light of the unexpectedly high Arctic sea ice loss this summer.

One more point--global warming skeptics often criticize using computer model climate predictions as a basis for policy decisions. These models are too uncertain, they say. Well, the uncertainty goes both way--sometimes the models will underestimate climate change. We should have learned this lesson when the ozone hole opened up--another case where the models failed to predict a major climate change. The atmosphere is not the well-behaved, predictable entity the models try to approximate it as. The atmosphere is wild, chaotic, incredibly complex, and prone to sudden unexpected shifts. By pumping large amounts of greenhouse gases into the air, we have destabilized the climate and pushed the atmosphere into a new state it has never been in before. We can expect many more surprises that the models will not predict. Some of these may be pleasant surprises, but I am expecting mostly nasty surprises.

Jeff Masters - Weather Underground

Buy land in Hattieville! (nice beach soon come)

Please post one acre parcel price when lots become available!

I'll be 80 years old then and probably won't care much about any of this.
I have to believe that living through the population bomb era and the atomic bomb era, all those other end of the world scenarios, I'm a little skeptical.

Speaking of the end of the world a friend had the most realistic idea I've heard to date.
The planet will survive all we can do to it, what will happen eventually is that the Earth will lower its habitability to make us go away and then restore itself to a glorious state, minus the infestation of human life.

Trying to say we are just a "blip", elbert?

I would agree.

Have you ever heard of the Baloney Detection Kit
Be suspicious of people saying "scientist say"
Wherever possible there must be independent confirmation of the facts
* Encourage substantive debate on the evidence by knowledgeable proponents of all points of view.
* Arguments from authority carry little weight (in science there are no "authorities").
* Spin more than one hypothesis - don't simply run with the first idea that caught your fancy.
* Try not to get overly attached to a hypothesis just because it's yours.
* Quantify, wherever possible.
* If there is a chain of argument every link in the chain must work.
if there are two hypothesis that explain the data equally well choose the simpler.
Most of the time it comes out Baloney
but I think its blip for us

Elbert, I agree with your friend. We aren't killing the planet, we're only killing ourselves. At the rate we're going we'll be successful sooner rather than later.

Totally agree, the planet will survive and as far as the evolutionary chain goes we are but just a blip (unless we choose to be otherwise.)

Humans are nothing but a 'Boil on the ass of Mother Nature'
She has the elimination process started already. Aids is a good example.
When She has had enough she will purge herself of humanity.
And, I hate to admit it but, the human race deserves it.

ITS INTERESTING TO SCAN THE WEB FOR ARTICLES FROM THE 1970'S PROCLAIMING THE COMING OF THE NEXT ICE AGE: EVEN MORE INTERESTING TO NOTE THAT SOME OF THE GLOBAL WARMING PROPONENTS OF TODAY HAVE SWITCHED THEIR ANTICIPATED TEMPERATURE EXTREMES OVER THE LAST 30 OR SO YEARS, BUT STILL BLAME THE SAME PEOPLE (BIG BUSINESS, OIL COMPANIES, REPUBLICANS, ETC)FOR WHATEVER DIRE CLIMATIC STATE THEY ARE PREDICTING NEXT

I don't understand global warming nay-sayers. If we all live a more environmentally friendly lifestyle and it turns out the whole thing was a hoax, we'll still have a cleaner planet as a result. What's the problem with that?

Nothing.

I AGREE TOTALLY BIG MIKE: I FULLY ADVOCATE PERSONAL RESPONSABILITY, NOT JUST FROM AN ENVIRONMENTAL STANDPOINT, BUT IN ALL AREAS OF ONE'S LIFE. THE LESS GOVERMENT INTERVENTION I HAVE REGARDING WHAT I EAT, DRINK, SMOKE AND DO, THE HAPPIER I'LL BE, BUT I DO GET A LITTLE ANNOYED WHEN I GET LECTURED TO BY SOMEONE WHO DRIVES THEIR PRIUS TO THE AIRPORT BEFORE BOARDING A PRIVATE JET, WHILE BUYING "CARBON CREDITS" FROM A COMPANY THAT THEY OWN......

I would love to see hybrid cars and even more what it would do to shake up world economy.
To bad the world can't tool around in golf carts like we do.

CHEVROLET HAS A FLEET OF 200 HYDROGEN CELL POWERED EQUINOX'S IS SERVICE IN 3 MAJOR CITY'S IN THE USA...THEY APPEAR VERY PROMISING, AND SHOULD BE AVAILABLE IN 2010/11 IF THE INFO THEY GAVE US AT LAST YEARS DEALER MEETINGS STAYS ON TRACK.
THE BIGGEST PROBLEM WITH THE CURRENT HYBRIDS IS THAT THE STATS THEY GIVE FOR MPG ARE TOTALLY UNREALISTIC, AS THEY SWITCH FROM GAS TO ELECTRIC POWER AND TOYOTA HAS RECENTLY HAD TO RE LABEL THE MILEAGE ESTIMATES THEIR PRIUS MODELS.
THE CURRENT YEAR MODEL SUBURBANS, TAHOES AVALANCHES AND SILVERADO TRUCKS, AS WELL AS SOME CAR MODELS HAVE AN 8 CYLINDER ENGINE THAT RETARDS TO 4 CYLINDERS AT HIGHWAY SPEEDS, BUT GOES BACK TO 8 CYLINDERS FOR PASSING ETC.
I GET 22-23 MPG FROM A FULL SIZE CREW CAB TRUCK, WHICH IS A BIG IMPROVEMENT OVER PREVIOUS MODELS: WHEN YOU LIVE (AS WE DO) 32 MILES FROM TOWN, AND HAVE SEVERAL HORSES TO CARE FOR, A TRUCK IS A WORK VEHICLE, NOT A LUXURY ITEM, SO ITS GOOD TO SEE PROGRESS MADE BY ALL THE WORLDS AUTO MAKERS, EVEN THOUGH IS LONG OVERDUE

It's always interesting to read 'facts' on climate change. No doubt about it that we are seeing climate change but to blame everything on CO2 !!!. Before you shoot me for saying so..consider these few snippits.
1. The biggest greenhouse gas is water vapour. (BTW..hydrogen based engine produces more water vapour than a gas engine)
2. Deforestaation is another word for removing a CO2 sponge.
3. Greenhouse gas affects have been blamed for reducing the effects of pollution...isn't that a good thing??
4. Greenland ice is melting..true..but they forget to mention that Antartic ice is getting thicker. (not the ice shelf...the land ice).
5. All glaciers are melting. But we only monitor 5-10% of the worlds glaciers. Of the missing 90% some are actually growing.

I doubt very much there is such a thing as a scientist who understands..the media of course have it all worked out!!

Strangly enough the same scientists predicting global warning also say it will cause currents to shift and cause a cooling of the artic and hello next ice age....complicated stuff eh.
Sounds to me just like the cycles the planet has gone through before. A simplistic view..maybe....But I read an official scientic release (ok..it was in the paper)a few days ago that 1/3 of greenhous gases is methane and most of the worlds methane production comes form the backsides of pigs and cows....The brilliant enviromentalist answer was that we stop eating meat so we won't need cattle!! My answer would be for everyone to own a cow, plumb its butt into the house and cut my natural gas bill...:)

The bottom line..cut polution, smog etc, curb the use of limited resources, try out new technologies so you can guage whether its actually a good idea and walk the talk if you are really concerned....otherwise get on with life and adapt to changes which are going to happen regardless of what we do. (unless of course we turn the lights off..retire to our caves, freeze in winter, grow trees instead of food and shoot all the cows...:)


I grow my owm veg as much as possible, compost all waste, use solar panels to cut my electricity bills and drive a V8 extended cab on 85% ethenol...but I'm buggered if I'm going to give up steak and pork ribs. BTW... it snowed today...global warming???

Wonder how many Ford Expeditions Al will buy with his money?

http://www.theage.com.au/news/national/p...9881602765.html

mmmm. I know what I'm having for lunch!

Kyoto is a total crock of sh*t. The countries signing Kyoto have INCREASED their carbon output since ratification. If Gore's hub-bub about Kyoto is that the U.S. simply look good, fine. Otherwise shut up already!

Hear! hear!

http://www.youtube.com/watch?v=oZrhG2iT3H0

Is that the Amboy Dukes doing back up?
cute

Love IT..... He can't sing any better than he can speak....

Oh boy love the inspirations caption at the end!

FAILURE
When your best just is'nt good enough
Or
When you just are'nt good enough

My eye-sight is going with my mind, waist, hair and all my other old good parts.....

Amen

might be the Perth Amboy Dukes, elbert!

Most of us talk about it, complain about it and cuss the government for not fixing it. And I agree with most of the opinions and comments made here on the subject. After all, the governments of the world have proved over and over again that they are incapable of managing money, at any level, and are totally incapable of stratigic planning, at any level, which would resolve the problems we face with energy, health, global warming, national security, ETC,ETc. Example; National security consists of having people take their shoes off at airports and building a fence across Texas.

IT’S (THE YOUTUBE SONG) BY PAUL SHANKLIN, WHO DOES MOST OF THE PARODY’S ON THE RUSH LIMBAUGH SHOW: THE JESSIE JACKSON AND AL SHARPTON ONES ARE GREAT, AS ARE THE ELVIS "IN THE GHETTO", AND JOHN EDWARDS "BRECK GIRL" BUT NOTHING COMPARES TO THE CLINTON SPOOFS. LINK AT www.rushlimbaugh.com OR www.paulshanklin.com TO BUY OR DOWNLOAD

http://www.youtube.com/watch?v=7P0HV7uAXx8

tread carefully there, pugwash. Rush is a dirty word hereabouts!

ITS OK RYKAT, I BUY CARBON CREDITS WHENEVER I LISTEN......

3 hours a day, 5 days a week.....that means I gotta plant 365,000 trees this year if I wanna keep listenin?

Just curious, Pugwash. What is the significance of "pugwash"? I have pugs, and the idea of washing them is not my favorite thing to contemplate, hence my curiousity.

To the person wishing that we could all tool around in golf carts.....think about how that electricity is produced to power said cart.....burning fossil fuels thus adding to the carbon output.

too bad they dont make golf carts powered by coal. that'd be fun stinkin' up the whole town and of course all the golf courses then one could dump the ashes in the ocean - proper disposal of course!
oops gotta go havent outputted enough carbon yet today!

Your methane output seems fairly healthy today.

One should get so close to be aware!

I think Belize has gone Hydro with the electricity. Lots from Mexico but The new Hydro project started up now with hopes of less purchesed from Mexico.

HEY BOBBER,
CAPTAIN PUGWASH WAS A CARTOON PIRATE IN AN OLD ENGLISH KIDS PROGRAM IN THE 60'S. HE WAS THE FEARLESS LEADER OF MASTER MATE, TOM THE CABIN BOY, WILLY AND BARNABUS AS THEY BATTLED CUT-THROAT JAKE FOR MASTERY OF THE SEAS. MY WIFE ANOUNCED THAT STANDING AT THE HELM OF MY BOAT AS IT SAT ON A TRAILER BEHIND MY HOUSE IN UTAH "YOU LOOK LIKE CAPTAIN PUGWASH" AND SHE WHISTLES THE THEME TUNE WHENEVER I GO OUT TO DO ANY WORK ON IT (THE BOAT)
http://en.wikipedia.org/wiki/Captain_Pugwash

Arctic sea ice begins to re-freeze
This summer's dramatic loss of Arctic sea ice peaked on September 15, and the polar ice cap is finally beginning to re-freeze, according to a press release http://nsidc.org/news/press/2007_seaiceminimum/20071001_pressrelease.html
issued by the National Snow and Ice Data Center on October 1. Extent of the September polar sea ice fell 39%, compared to the 1979-2000 average. To put this loss in perspective, in one year we lost as much ice as we lost during the previous 28 years. Summertime Arctic sea ice is now at 50% of what it was in the 1950s (Figure 1). One may look at at graph and wonder, but what about sea ice loss in other seasons? It hasn't been nearly so severe. True, but it is the summer ice we care most about, since summer is when the thick, multi-year ice melts, which can then precondition the Arctic for much greater ice loss in future years. As sea ice melts in response to rising temperatures, more of the dark ocean is exposed, allowing it to absorb more of the sun's energy. This further increases air temperatures, ocean temperatures, and ice melt in a process know as the "ice-albedo feedback" (albedo means how much sunlight a surface reflects). There is an excellent chance that the summer of 2007 will be remembered as the "tipping point" for Arctic sea ice, when an irreversible ice-albedo feedback process firmly established itself.



Figure 1. Arctic sea ice extent since 1900, as estimated from satellite and ship reports compiled by Walsh and Chapman (2001). Image credit: University of Illinois cryosphere group. http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.updated.jpg

Northwest Passage opens for the first time in recorded history
Long before the Panama and Suez Canals made commercial trading between the Atlantic and Pacific Oceans economically feasible, ships made the long and perilous trip around the African and South America continents. Explorers, traders, and world leaders looking for faster and less dangerous shipping routes to far-away areas of the world have long eyed two routes through the ice-choked Arctic Ocean--the fabled Northwest Passage, through the cold Arctic waters north of Canada, and the Northeast Passage, extending along the northern coast of Russia. The first recorded attempt to find and sail the Northwest Passage was in 1497, and ended in failure. The thick ice choking the waterways thwarted all attempts at passage for the next four centuries. Finally, in 1905, Roald Amundsen completed the first successful navigation of the Northwest Passage. It took his ship two-and-a-half years to navigate through narrow passages of open water, and his ship spent two cold, dark winters locked in the ice during the feat. More recently, icebreakers and ice-strengthened ships have on occasion battered their way through the ice-blocked route.



Figure 2. The Northwest Passage shipping route (red line) and Northeast Passage (green line) superimposed on an ice coverage map from August 22, 2007. The Northwest Passage was ice-free and navigable for 36 days between August 14 and September 18, 2007. The Northeast Passage was blocked by a narrow strip of ice most of the summer. Image credit: National Snow and Ice Data Center. http://nsidc.org/news/press/2007_seaiceminimum/20070810_index.html

Times are changing. In 2001, the Bering Strait, a key portion of both the Northwest and Northeast Passages, was completely ice free. This was followed in 2005 by record-breaking sea-ice melt in the Arctic, leading to the first ever recorded opening of the Northeast Passage. The fabled Northwest Passage remained closed in 2005. Arctic ice recovered a bit in 2006, and both passages remained closed. But the unprecedented melting during the summer of 2007 saw the Northwest Passage become ice-free and navigable along its entire length without the need for an icebreaker as of August 14, 2007. Remarkably, the Northwest Passage remained ice-free for 36 days, finally refreezing over a small section on September 19. The Northeast Passage was blocked by a narrow strip of ice all summer. However, this strip of ice thinned to just 30% coverage on September 25 and 26, making the Northeast Passage passable for ordinary ships on those days.

When is the last time the Northwest Passage was open?
We can be sure the Northwest Passage was never open from 1900 on, as we have detailed ice edge records from ships. It is very unlikely the Passage was open between 1497 and 1900, since this was a cold period in the northern latitudes known as "The Little Ice Age". Ships periodically attempted the Passage and were foiled during this period, and the native Inuit people have no historical tales of the Passage being navigable at any time in the past.

A good candidate for the last previous opening of the Northwest Passage was the period 5,000-7,000 years ago, when the Earth's orbital variations brought more sunlight to the Arctic in summer than at present. Prior to that, the Passage was probably open during the last inter-glacial period, 120,000 years ago. Temperatures then were 2-3 degrees Centigrade higher than present-day temperatures, and sea levels were 4-6 meters higher.

Final thoughts
If we have reached the tipping point for Arctic ice, what are the implications? I'll discuss this more in a future blog. Sea ice is very complicated, and it is not a sure thing that we have reached the tipping point. For more on the complexities of sea ice, read wunderblogger Dr. Ricky Rood's latest blog. http://www.wunderground.com/blog/RickyRood/comment.html?entrynum=45&tstamp=200710

NASA http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14572 has posted a beautiful satellite image of the Arctic ice cap at the September 15 2007 minimum, showing the open water of the Northwest Passage.

I thank Edalin Michael of the University of Michigan's School of Natural Resources and Robert Grumbine of NOAA's Sea Ice Group for their contributions to this blog.

References
Walsh, J.E and W.L.Chapman, 2001, "Twentieth-century sea ice variations from observational data" http://www.ingentaconnect.com/content/igsoc/agl/2001/00000033/00000001/art00071 , Annals of Glaciology, 33, Number 1, January 2001 , pp. 444-448

Jeff Masters