Arctic Sea Ice Summer Melt Wrap-Up: 2007 Shatters All Previous Record Lows
02 October 2007
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| Time series plot of 2007 summer sea ice extent in context with other years. 2007, shown in solid blue, is far below the previous record year of 2005, shown as a dashed line; September 2007 was 36% below where we would expect to be in an average year, shown in solid gray. Click to enlarge. |
Arctic sea ice during the 2007 melt season plummeted to the lowest levels since satellite measurements began in 1979, according to the National Snow and Ice Data Center (NSIDC) at the University of Colorado at Boulder.
The average sea ice extent for the month of September was 4.28 million square kilometers (1.65 million square miles), the lowest September on record. This low shatters the previous record for the month—5.57 million square kilometers in September 2005—by 23%.
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| September ice extent from 1979 to 2007 shows an obvious decline. The September rate of sea ice decline since 1979 is now approximately 10 percent per decade, or 72,000 square kilometers (28,000 square miles) per year. Click to enlarge. |
At the end of the melt season, September 2007 sea ice was 39 percent below the long-term average from 1979 to 2000. If ship and aircraft records from before the satellite era are taken into account, sea ice may have fallen by as much as 50% from the 1950s. The September rate of sea ice decline since 1979 is now approximately 10% per decade, or 72,000 square kilometers (28,000 square miles) per year.
Arctic sea ice has long been recognized as a sensitive climate indicator.
Computer projections have consistently shown that as global temperatures rise, the sea ice cover will begin to shrink. While a number of natural factors have certainly contributed to the overall decline in sea ice, the effects of greenhouse warming are now coming through loud and clear.
—Mark Serreze, NSIDC Senior Scientist
One factor that contributed to this fall’s extreme decline was that the ice was entering the melt season in an already weakened state. Another factor that conspired to accelerate the ice loss this summer was an unusual atmospheric pattern, with persistent high atmospheric pressures over the central Arctic Ocean and lower pressures over Siberia. The scientists noted that skies were fairly clear under the high-pressure cell, promoting strong melt. At the same time, the pattern of winds pumped warm air into the region. While the warm winds fostered further melt, they also helped push ice away from the Siberian shore.
While the decline of the ice started out fairly slowly in spring and early summer, it accelerated rapidly in July. By mid-August, we had already shattered all previous records for ice extent.
—Walt Meier, NSIDC Research Scientist
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| This animation shows two aspects of sea ice change: First, it shows that as the years unfold, September sea ice is gradually dwindling. Second, it shows that even compared to the very lowest years on record, 2007 sea ice has visibly declined. On the right is the average extent in September 2007. On the left is an animation that shows September sea ice extent, beginning with 1979 and ending with 2006. Open animation in new window. |
Arctic sea ice receded so much that the fabled Northwest Passage completely opened for the first time in human memory. Explorers and other seafarers had long recognized that this passage, through the straits of the Canadian Arctic Archipelago, represented a potential shortcut from the Pacific to the Atlantic. Roald Amundsen began the first successful navigation of the route starting in 1903. It took his group two-and-a-half years to leapfrog through narrow passages of open water, with their ship locked in the frozen ice through two cold, dark winters. More recently, icebreakers and ice-strengthened ships have on occasion traversed the normally ice-choked route. However, by the end of the 2007 melt season, a standard ocean-going vessel could have sailed smoothly through. On the other hand, the Northern Sea Route, a shortcut along the Eurasian coast that is often at least partially open, was completely blocked by a band of ice this year.
In addition to the record-breaking retreat of sea ice, NSIDC scientists also noted that the date of the lowest sea ice extent, or the absolute minimum, has shifted to later in the year. This year, the five-day running minimum occurred on September 16, 2007; from 1979 to 2000, the minimum usually occurred on September 12.
What we’ve seen this year fits the profile of lengthening melt seasons, which is no surprise. As the system warms up, spring melt will tend to come earlier and autumn freezing will begin later.
—Ted Scambos, NSIDC Senior Scientist
Changes in sea ice extent, timing, ice thickness, and seasonal fluctuations are already having an impact on the people, plants, and animals that live in the Arctic. NSIDC scientists monitor and study Arctic sea ice year round, analyzing satellite data and seeking to understand the regional changes and complex feedbacks that we are seeing.
he sea ice cover is in a downward spiral and may have passed the point of no return. As the years go by, we are losing more and more ice in summer, and growing back less and less ice in winter. We may well see an ice-free Arctic Ocean in summer within our lifetimes. The implications for global climate, as well as Arctic animals and people, are disturbing.
—Mark Serreze
Resources:
Meier, W.N., J. Stroeve, and F. Fetterer, 2007. “Whither Arctic sea ice? A clear signal of decline regionally, seasonally and extending beyond the satellite record,” Ann. Glaciol., vol. 46, pp. 428-434.
Serreze, M.C., M.M. Holland, and J. Stroeve, 2007. “Perspectives on the Arctic’s shrinking sea-ice cover”, Science, vol. 315, pp. 1533-1536, doi: 10.1126/science.1139426.
Stroeve J., M.M. Holland, W. Meier, T. Scambos, and M. Serreze, 2007. “Arctic sea ice decline: Faster than forecast”, Geophys. Res. Lett., vol. 34, L09501, doi: 10.1029/2007GL029703.
The only good thing about news like this is that it hopefully will open the eyes of the non-scientists so that they also can see that we have a problem that is real and serious.
In fact it is more than serious. It is life threatening of epic proportions.
The problem is that Global Warming will very soon increase temperature to the point where it will start to warm the oceans so that they in turn will release their gigantic reservoirs of trapped methane. This will lead to a runaway greenhouse effect that is bad news for everybody. It has happened several times before in the history of earth and each time the consequences were massive extinction of life. All kind of species will be hit; ocean life and land life.
For those who care I found a really good source on the Global Warming potential of oceanic methane. Bruce Buffett and David Archer. University of Chicago. They should be some of the most regarded and most knowledgeable scientist in the field. This paper is good reading and really is the “smoking gun” on Global Warming see http://geosci.uchicago.edu/~archer/reprints/buffett.2004.clathrates.pdf.
I quote their article “Preferred values for these parameters are taken from previous studies of both passive and active margins, yielding a global estimate of 3*10^18 g of carbon (3000 Gton C) in clathrate and 2*10^18 g (2000 Gton C) in methane bubbles. The predicted methane inventory decreases by 85% in response to 3 degree C of warming.”
To be sure, this is 5000 billion tons of pure carbon which translates into I believe about 10000 billion tons of CO2. For comparison this is 12.5 times the current level of CO2 in our atmosphere. It only takes 3 degree C increase in the global temperature to release most of it. In other words, the current global warming of now 0.7 degree Celsius only needs to increase some 2.3 degrees more to make that happen. The UN climate panel IPCC project is already predicting an increase of temperature by 1.1 to 6.4 °C (2.0 to 11.5 °F) between 1990 and 2100. And we have seen several times how they keep underestimating the real effects.
This is indeed bad. In a few decades the climate will be warm enough to warm the oceans so that they will release the ocean methane in a matter of a few hundred years more and then the planet will be about 10 degrees C warmer at equator and some 30-40 degrees C hotter at the poles. They will melt and the sea will rise about 70 meters (200 feet) as a consequence. The result is that 90-99% of all life on the planet will die out because they cannot adapt. Will humans die out? It is not going to be easy to survive for sure and I do not think present day technology will help many people to survive. I think we will survive with much better technology and those who can’t do that will die. But why make the whole planet ugly with very few species left etc?
We certainly live in a world of almost utter ignorance and lack of foresight. I hope these are the reasons that our leaders do nothing of any importance to stop Global Warming. I hope it is not just the cynical “hey we live great now and who cares about future generations we will be dead anyway when they start to suffer”.
Do something wherever you live and whatever your abilities. We need to focus all of our resources to fight this problem or there will be no future the next millions of years for most life on this planet.
More info here. http://en.wikipedia.org/wiki/Clathrate_gun_hypothesis
Posted by: Henrik | 02 October 2007 at 02:57 AM
The regression curve does indeed show a significant downward trend in arctic sea ice cover, but on past form 2007 is a wild aberration. The reasons for this are still unclear, it could be a freak phenomenon or an early indication that a linear regression will soon no longer be accurate enough.
A reliably ice-free passage through the arctic would be a good thing, but the price for it could prove steep: in addition to a more rapid rise in sea levels, we could see changes in atmospheric circulation patterns in the Northern Hemisphere. Our assumption has always been that such changes in climate happen very slowly, over the course of many decades or centuries. What if this time, they were to happen much faster, in the span of just one generation? Could our global economy and social structures cope?
Posted by: Rafael Seidl | 02 October 2007 at 03:36 AM
I don't think 90-99% of all life will die out, the climate change from the last ice age didn't kill off that many animals and plants, (just the big mammals and that was probably the human's fault) previous ice ages to warm ages did not kill off anything close to that many animals, if anything humans will directly kill of most of the life on the planet to make way for farm land. Humans will easily survive of course millions of refugees from countries that will be underwater will have to be dealt with.
Posted by: | 02 October 2007 at 06:26 AM
Claims that 90-99% of life will die out is pretty premature and alarmist. However, the point is well taken. During 'natural' ice ages, species had many, many generations too adapt. Now they do not.
Climate change isn't really the problem, the SPEED of the climate change is what's gonna get us.
Posted by: tato | 02 October 2007 at 06:51 AM
Its not the amount of chnge in temerature but the speed at which it could happen. Evolution does not happen in a few year time span. It takes generations of creatures to adapt. Look to bacteria and virus to see how long it takes to adapt. How many million generations of bacteria did it take before they began to be resistant to penicillan?
The concern of climate scientists and biologists alike is not as much as the amount of temperature change as it is how quickly it may happen. And keep in mind that it truly is climate change... it does not mean that everywhere gets warmer all year round. The midwest USA may become more arid and warm, while the SW USA may become tropical climate. Northern Europe may find itself a tundra, and central Africa may become the breadbowl of the world. Who knows? And that friends is what scars the hell out of the scientific community. Where doinf full scale climate experimentation with an closed system that we just happen to live in. Probably not a good idea.
Posted by: Eric S | 02 October 2007 at 07:02 AM
Climate change cycles happened many times before. What may make this one different seems to be the faster rate of change + possible deeper swing.
Of course since earth never had 7 billion inhabitants before, the adverse effects on human population will be multiplied.
How will current cold weather countries like Canada, Russia, Argentina, Greenland, northern Europe etc deal with 100 +++ million new migrants? Will Alberta be able to accommodate 10 million talibans to accellerate oil extraction from tar sands and liberate remaining (reduced) farm land areas for food production? etc.
At the current increasing rate of change, when are we going to start feeling or seeing the effects? Will it be as soon as 2050 or 2100?
We live about 200 Km north of North Pole USA (Plattsburg NY) and the climate has changed a lot in the last 50 years. Many months are already 3C and 4C above average. Wine grapes are doing much better than 10 years ago. McIntosh apples have problems dealing with longer, warmer growing seasons. Ski resorts have to deal with much shorter seasons etc. Are those early signs?
Posted by: Harvey D | 02 October 2007 at 07:47 AM
The Arctic sea ice is at all-time record low, and Antarctic sea ice is at all-time record high. The problem is that all-time record spans for only 28 years, which is nothing.
“Northwest Passage completely opened for the first time in human memory.” The guys are pathological liars, which is customary among AGW "scientists". Arctic sea ice was receding quite substantially in 1920-40s, which culminated in one-season return voyage through NW Passage by RCMP sergeant Henry Larsen in 1943, on 88-ton wooden schooner St Roch, propelled by sail and 300hp engine.
The biggest vessel to navigate NW passage was 150 000 ton US reinforced tanker Manhattan in 1969. On return voyage she holed the hull, and attempts to haul Alaskan oil to East bound US was abandoned for good. Only very naive person (like US politicians) could fantasize that once in couple of years two-three weeks ice opening in extremely treacherous waters could be of value to commercial shipping.
Military, research, and even lately tourist vessels (Google North West Passage tours) navigate NW passage occasionally, like US submarine Seadragon in 1960.
Posted by: Andrey | 02 October 2007 at 08:13 AM
Lowest levels in satellite-collected-data human memory, that is. When I was a child, there were pictures in the papers of the USS Polaris submarine on the surface in the open waters of the Arctic Ocean in the 1950's. Ice was notably scarce then, too.
A lot of the arctic ice has melted and the sea level in the Maldives has fallen, not risen. Maybe things aren't as simple or disastrous as some would like you to think.
Posted by: Arthur | 02 October 2007 at 09:52 AM
@Andrew:
Please read more than the first sentence of a paragraph before you post. Instead of taking 1 sentence out of it's context, I'll post the entire paragraph for you:
Arctic sea ice receded so much that the fabled Northwest Passage completely opened for the first time in human memory. Explorers and other seafarers had long recognized that this passage, through the straits of the Canadian Arctic Archipelago, represented a potential shortcut from the Pacific to the Atlantic. Roald Amundsen began the first successful navigation of the route starting in 1903. It took his group two-and-a-half years to leapfrog through narrow passages of open water, with their ship locked in the frozen ice through two cold, dark winters. More recently, icebreakers and ice-strengthened ships have on occasion traversed the normally ice-choked route. However, by the end of the 2007 melt season, a standard ocean-going vessel could have sailed smoothly through. On the other hand, the Northern Sea Route, a shortcut along the Eurasian coast that is often at least partially open, was completely blocked by a band of ice this year.
They recognize exactly what you're saying in your post, that other vessels have successfully navigated the northwestern passage. They also explain exactly what they mean by completely:
a standard ocean-going vessel could have sailed smoothly through
Note two words: "standard" and "smoothly", this does of course not apply to the 1969 attempt of the reinforced tanker Manhattan that you mention in your post. Neither to the other expeditions that took sometimes years to complete the voyage.
So they're not pathological liars. You should read more accurately.
Posted by: Anne | 02 October 2007 at 10:20 AM
And is it anything close to true to say "Antarctic sea ice is at all-time record high"? Antarctic ice sheets have broke off and disappeared over the last decade.
Posted by: Jim G. | 02 October 2007 at 11:08 AM
I've answered my own question:
http://www.dailytech.com/Antarctic+Ice+Levels+Hit+Record+High/article8871.htm
Posted by: Jim G. | 02 October 2007 at 11:24 AM
This whole "problem" could be solved if Al Gore would just make a visit to the Arctic - the well-documented "Gore Effect" would freeze the Arctic solid!
Posted by: Matthew | 02 October 2007 at 11:39 AM
While as the sea ice melting may be due to anthropogenic causes, we have so little data on previous ice coverage that it's hard to say what is the norm. There is anecdotal evidence that the northwest passage has been open a number of times in the last several hundred years.
Posted by: ROBBMOSS | 02 October 2007 at 12:59 PM
The idea that SH ice may grow in some areas is fairly old idea and may be a consequence of global warming.
http://www.nasa.gov/centers/goddard/news/topstory/2005/sea_ice.html
as this page illustrates. It is also occuring in the the center of Greenland, but it should be noted that the edges are breaking off more extensively as well. New Zealand is getting more wary of iceburgs for instance.
Countries are already staking claim to various parts of the artic shelf for exploration/exploitation. The russians recently did some extensive studies to bloister their own claims. We are entering a newer more tense geo/politcal period over the arctic and it's not only because our technology has improved to the point where we can take advantage of the area but because the area is becoming more ameloriative to our probings.
We are already experiencing a holocence species suppression/extinction event. Many species are endangered from the way we use the environment. I don't know if global warming will push the environment into a Permian extinction scenario (I doubt it) but even if it doesn't, the global warming we already do is not helping things out.
http://en.wikipedia.org/wiki/Holocene_extinction_event
As for dailytech??? I would take anything Mr. Asher says with a grain of salt. As an example, he likes comparing the cost of production of nuclear energy to the LCOE of solar. Two obviously different things. As well, he dismissed DOE studies on the cost of solar (15-22c) for that of a website called solarbuzz(27c) on the grounds that DOE numbers were "hypothetical". Such argumentative stubborness to anything contrary to his opinions makes anything he has to say suspect.
Posted by: aym | 02 October 2007 at 02:24 PM
...But what of the huge rise in sea level that was predicted? I'm not seeing it.
Don
Kansas City
Posted by: Don A. Gilmore | 02 October 2007 at 02:24 PM
Once I’ve read a theory that cooling/warming of polar regions occurs in counter phases: when Arctic is cooling, Antarctica is melting, and vise versa. The reason of this is multidecadal oscillations in ocean currents (and corresponding winds), which are the biggest supplier of heat to polar regions. Sun (and GHG effects) does not matter much in polar regions – surface is inclined too steep, path of solar light in atmosphere is much longer, and there is half year night – quite enough to freeze everything that melted in summer day.
Posted by: Andrey | 02 October 2007 at 04:49 PM
We have observational data going back to the late 1800s. This summer's sea ice extent has shrunk to about half of what it was. The margin of error is considerably higher pre 1950s, but it's not off so much that they misplaced half of the ice.
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.1900-2007.jpg
If you compare the Antarctic and Arctic sea ice anomalies, you can see that "near record" Antarctic extent doesn't mean much given that it's been bouncing around a flat trend for the entire record. The Arctic sea ice extent is another story.
Antarctic:
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.anom.south.jpg
Arctic:
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.anom.jpg
Posted by: cce | 02 October 2007 at 06:34 PM
Also, it's somewhat elementary but necessary to point out that melting sea ice does not contribute to sea level rise. It does, however, put increased pressure on Greenland's ice sheet, which does contribute to sea level rise.
Posted by: cce | 02 October 2007 at 06:38 PM
Cce:
Satellites measure total ice area, not ice extend as meteostations before. Also satellites count melted water ponds on the ice surface as open water, since such dramatic numbers of decreased sea ice. Satellite data is simply not compatible with previous records, especially before aerial ice reconessance began – about 60 years ago.
There is scientific evidence, that about 3000 years ago NW Passage was so dramatically free of ice, that bowhead whales routinely traveled from Pacific to Atlantic. It is not the case for current Arctic ice retreat, at least for now.
Posted by: Andrey | 02 October 2007 at 08:11 PM
Andrey, care to comment on Anne's post? Who is trying to fool who?
Posted by: marcus | 02 October 2007 at 09:29 PM
It is of cause difficult to say precisely how much extinction of life the current manmade Global Warming will cause. It will depend predominantly on the coming action or >lack of action< to fight manmade Global Warming.
It is a scientifically established fact that the >nature made< end Permian extinction event caused about 90-95% of all species to die out 250 million years ago. This was long before humans existed and even long before the dinosaurs ruled the Earth.
The killing period of the end Permian event lasted about 80000 years. In the first 40000 years it was caused by massive volcanic activity in an area known as the Siberian Trap that contains large natural reservoirs of oil and coal. Huge amounts of these fossils burned off because of the volcanic activity and that gradually caused a global warming effect of about 5 degrees Celsius. The remaining 40000 years of additional killing of life was caused by a further increase in the global temperature of also about 5 degrees Celsius brining the combined temperature increase to 10 degrees Celsius during the entire period of 80000 years. This additional warming of 5 degree Celsius was caused because the first 40000 years of global warming increased the ocean temperatures to the point where they started to release their otherwise trapped reservoirs of methane. This methane accumulates through millions of years as dead organic matter from the surface of the ocean rains down to the button of the ocean were it rot and create methane that is trapped because of the high water pressure.
The end Permian extinction event was bad, really bad. Unfortunately, there are two good reasons to suggest that extinction from manmade Global Warming will be much worse. The reasons are:
1) >Modern civilization< is much more effective with regard to finding and burning fossil fuels than any isolated prehistoric volcano activity or meteor impacts could possibly be. If there is a reservoir of fossil fuel anywhere on the planet humans are able to find it and burn it.
2) >SPEED<. This has already been pointed out by others. The end Permian event took only 80000 years and most species (apart from microbes and insects with short life cycles) did therefore not have enough time to adapt. This time humans will have burned off all of the fossil fuel on the entire planet in less than 300 years and we are already halfway into that process. As a result, this time the speed of manmade Global Warming will be much faster and therefore far more deadly.
As far as I can see 95-99% extinction of all life on the planet as a result of uncontrolled manmade Global Warming is a conservative estimate. It is not the worst case scenario.
In fact I do not think that mass extinction of life is avoidable at this point in time but there is hope that it can be greatly minimized to perhaps 50% extinction of all life. It can be minimized if we mobilize a massive >will< to fight Global Warming using all available resources. The extinction of life from manmade Global Warming will be more severe the longer we wait to do anything serious about it. Serious is first to slow down CO2 emissions then to stop it entirely and finally to bring back the atmospheric CO2 level to its preindustrial level. This should be our objective in our war with Global Warming. That will take hundreds of years but we can do it if we have the > will< to do so. There is hope.
If we do not have the >will< then I guess mankind simply gets what it deserves. Who knows even in that dreadful case intelligent life may pop up once again million of years further down the road of evolution. They will get another chance to prove whether they are worthy of their special gift.
***
For an easy to read and reliable source on the end Permian extinction event I recommend this article by BBC. The conclusions and final explanations and given at the end of the article so it is important to read all of it. I have little hope a guy like Andrey is patient enough to read it through or even to check the source.
http://www.bbc.co.uk/science/horizon/2002/dayearthdied.shtml
For a source on the deposits of fossils at the Siberian Basin see
Peterson, J.A. and Clarke, J.W., 1991. Geology and Hydrocarbon Habitat of the West Siberian Basin, 32. American Association of Petroleum Geologists, Tulsa, Oklahoma, 93 pp.
Posted by: Henrik | 03 October 2007 at 05:07 AM
Marcus:
Northwest passage was open regularly in 19 and 20 century. Steam yacht of Amundsen and 150 hp schooner of Larsen (on first crossing) were too slow to make thousand miles of journey in one short navigation season, and have to spent one or two winters trapped in ice in harbors, where they hided from being crushed by moving ice fields in the open sea. At the spring they just can not free their vessels to reach open water.
Expeditions of Parry 1819-1920, Ross 1829-1833, Franklin 1845-1848, McLure 1850-1854 cleared most treacherous parts of the journey, but were unable to withstand next winter in Arctic. Passage was navigable, just their sail vessels were too slow. Otherwise from these expeditions, there is no “human memory” about NW Passage, because nomadic tribes sparsely populating these inhospitable lands do not keep record about state of the passage.
This facts is well known to everybody interested in the subject. “Northwest Passage completely opened for the first time in human memory” is a lie, and pretty dumb one.
Now, Google “Northwest first time”, and take a look how many headlines parroted this lie to the public.
Posted by: Andrey | 03 October 2007 at 07:35 AM
Henrik,
Interesting comments.
Are we smart enough to take all actions required to slow down climate warming enough to delay the next natural cycle?
If so, (or not too late) by how many years or centuries.
USA and Canada with 25 tonnes/GHG/per capita/yr have a very long way to go. Sweeden has only 8 tonnes and China about 3 tonnes.
The major polluters are right here and our Federal Administrations are not doing much.
Posted by: Harvey D | 03 October 2007 at 08:15 AM
Some posters see the evidence of more sea ice at Antarctica as >proof< that Global Warming is a myth. This is ridiculously misperceived. First of all, the local phenomena in the Antarctica (or the Arctic for that case) cannot be used to prove global phenomena. Andrey is repeating this mistake all the time in his arguments here and elsewhere. It is the overall global temperature that matters and this temperature is rising without any scientific doubt whatsoever. Secondly, the increase that is observed in Antarctica is small and statistically insignificant unlike the change that is observed in the Arctic which is large and statistically highly significant.
For a reliable source on the statistical significance of the Antarctic versus Arctic sea ice see
http://nsidc.org/seaice/characteristics/difference.html
Scroll down to the end of this web page and look at the table called “Summary of differences between Arctic and Antarctic sea ice characteristics”. Then read the colon called “Trend” and you will see the data on statistical significance.
Posted by: | 03 October 2007 at 08:35 AM
Forgot my ID
Posted by: Henrik | 03 October 2007 at 08:37 AM