Tag: Arctic

Sugar coated iceberg

Polarbear.jpg Prognostications on the fate of the Arctic sea ice this boreal summer are coming in thick and fast. The National Snow and Ice Data Centre in the US has updated its summer news page with the latest data and some projections of what might happen:

Spring has arrived in the Arctic. After peaking at 15.21 million square kilometers (5.87 million square miles) in the second week of March, Arctic sea ice extent has declined through the month of April. April extent has not fallen below the lowest April extent on record, but it is still below the long-term average. Taken together, an assessment of the available evidence, detailed below, points to another extreme September sea ice minimum. Could the North Pole be ice free this melt season? Given that this region is currently covered with first-year ice, that seems quite possible.

Most striking are the estimates of this summer’s likely minimum based on the melting rates observed over the last 25 years.

Icepredict0805.png

“To avoid beating the September 2007 record low, more than 50% of this year’s first-year ice would have to survive; this has only happened once in the last 25 years, in 1996.”

Meanwhile, Andy Revkin at the New York Times has been asking sea ice researchers for their views. You can read their replies in the comments to his post. A number of well-known names are backing a new record, including BIll Chapman, the researcher responsible for the excellent Cryosphere Today site (I want to get an iPhone so that I can try out the special graphics CT provides), who writes:

The two wild cards remaining would be (1) how thick is this first-year ice and (2) will it be warm enough to melt the first-year ice this summer? Since temperatures over the central Arctic were normal to above normal this past winter and spring, I don’t think the thickness will be too great. The key will be June temperatures and cloud cover in the central Arctic. Given relatively clear conditions and an early to average start to the melt of the central Arctic, the albedo will lower and the process will be in motion to easily melt that first year ice. In fact, the only thing that could prevent a record would be a colder than average summer – especially early summer. Given recent history and our penchant for burning fossil fuels, I’d consider this somewhat unlikely.

I say the odds favor a new NH record minimum – put my money there.

My money’s already there… Good to know I’m backing the form horse, even if I would rather lose.

Cool for cats

FishThe second climate forecast for the next decade has been published [Advancing decadal-scale climate prediction in the North Atlantic sector, Keenlyside et al, Nature, behind a firewall but available here], and the world’s media – and a fair number of blogs – have jumped all over its suggestion that there might be some regional cooling over the next decade. Richard Black at the BBC headlined his piece “Next decade ‘may see no warming'” , the New York Times‘ Andy Revkin settled for “In a New Climate Model, Short-Term Cooling in a Warmer World”, which becomes “Next decade may see no warming” at frogblog and “Global Warming on hold until 2015 claim Germans” at Kiwiblog. So what’s going on? Is global warming really on hold?

Continue reading “Cool for cats”

Skating away (on the thin ice of a new day)

Mar-2008-Ice-Age.jpg A new forecast for this summer’s Arctic sea ice melt suggests that there’s a 60% chance that this year’s minimum will set a new record. Work by researchers at the University of Colorado’s Center for Astrodynamics Research shows that the current ice is much thinner than usual:

“The current Arctic ice cover is thinner and younger than at any previous time in our recorded history, and this sets the stage for rapid melt and a new record low,” said Research Associate Sheldon Drobot, who leads CCAR’s Arctic Regional Ice Forecasting System group in CU-Boulder’s aerospace engineering sciences department. Overall, 63 percent of the Arctic ice cover is younger than average, and only 2 percent is older than average, according to Drobot.

The image above shows the age of the current ice cover compared to average for this time of year (you can click on the image to see a larger version). Yellow is the same as average, red is younger. For the bigger picture, visit the Arctic Ice Forecasting System pages at UC.

This has prompted me to increase my sea ice bet with William “Stoat” Connolley by £10 to £30 (plus a signed copy of Hot Topic). With the seasonal melt speeding up, the race is on…

[Hat-tip to Eli Rabett]

It’s a gas, gas, gas

arcticmethane.jpg It’s not good news. The USA’s National Oceanic and Atmospheric Administration (NOAA) has produced its annual report on greenhouse gas levels in the atmosphere, and carbon dioxide concentration continues its accelerated growth. And there are signs that methane levels are beginning to rise, after a decade of remaining more or less static. The BBC reports:

NOAA figures show CO2 concentrations rising by 2.4 parts per million (ppm) from 2006 to 2007. By comparison, the average annual increase between 1979 and 2007 was 1.65ppm.

The methane rise is worrying because it’s a very powerful greenhouse gas (23 times as effective at trapping heat as CO2), and there are a number of positive feedbacks that could come into play as the planet warms. From the NOAA release:

Rapidly growing industrialization in Asia and rising wetland emissions in the Arctic and tropics are the most likely causes of the recent methane increase, said scientist Ed Dlugokencky from NOAA’s Earth System Research Laboratory. ”We’re on the lookout for the first sign of a methane release from thawing Arctic permafrost,” said Dlugokencky. “It’s too soon to tell whether last year’s spike in emissions includes the start of such a trend.”

Permafrost is one thing, methane hydrates are another. Sometimes called burning ice, methane hydrates (aka clathrates) are a mixture of ice and methane that exist in large quantities on the sea floor – and there are particularly large amounts in the shallow Arctic seas north of Russia and Siberia (more info at Climate Progress). At the recent European Geophysical Union conference in Vienna, a Russian scientist discussed the issue. From SpiegelOnline:

In the permafrost bottom of the 200-meter-deep sea [off the northern coast of Siberia], enormous stores of gas hydrates lie dormant in mighty frozen layers of sediment. The carbon content of the ice-and-methane mixture here is estimated at 540 billion tons. “This submarine hydrate was considered stable until now,” says the Russian biogeochemist Natalia Shakhova, currently a guest scientist at the University of Alaska in Fairbanks who is also a member of the Pacific Institute of Geography at the Russian Academy of Sciences in Vladivostok.

The permafrost has grown porous, says Shakhova, and already the shelf sea has become “a source of methane passing into the atmosphere.” The Russian scientists have estimated what might happen when this Siberian permafrost-seal thaws completely and all the stored gas escapes. They believe the methane content of the planet’s atmosphere would increase twelvefold. “The result would be catastrophic global warming,” say the scientists.

The SpeigeOnline article is worth reading in full. Shakova’s observations of methane emissions hint at an explanation for the increase in global atmospheric methane. If that’s the case – and its too early to say for sure – then we may be seeing the beginnings of one of the most worrying of the positive carbon cycle feedbacks – one that could potentially make anything we do to cut CO2 emissions the equivalent of pissing in the wind.

[Hat tip for the Spiegel piece to No Right Turn – I’m frankly amazed the EGU paper hasn’t had much more coverage in the world’s media.]

[Update for the interested: The EGU abstract for Shakhova’s paper is here [PDF]. Here’s the last few words:

“…we consider release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time. That may cause ~ 12-times increase of modern atmospheric methane burden with consequent catastrophic greenhouse warming.”

“Abrupt release at any time”. That’s truly alarming.]

“The Arctic ice is back to normal.” Yeah, right. #2


This latest New Scientist video accompanies a news item headlined “North Pole could be ice free in 2008“, and shows multi-year ice moving out of the Arctic over winter.

“The set-up for this summer is disturbing,” says Mark Serreze, of the US National Snow and Ice Data Center (NSIDC). A number of factors have this year led to most of the Arctic ice being thin and vulnerable as it enters its summer melting season.”

Also of interest in the video: look at the large cracks in the thicker ice north of Canada.