Reelin’ in the year

The International Polar Year (IPY) 2007-8 formally draws to a close today, and when today arrives in Geneva there will be a press conference to mark the release of a summary report, The State of Polar Research [PDF], which covers some of the preliminary findings. [BBC report here]. In the run up to this event, there’s been a blizzard (…sorry) of stories from the teams working at both ends of the world, and they make fascinating reading. From huge pools of freshwater building up in the Arctic Ocean to new mountain ranges as big as the Alps under Antarctica, methane plumes off Siberia and the death knell for summer sea ice in the Arctic, there’s a lot to cover…

A general overview of the Arctic studies over the IPY, given the headline Arctic sea ice will probably not recover finishes with this sobering paragraph:

Our main conclusions so far indicates that there is a very low probability that Arctic sea ice will ever recover. […] The entire Arctic system is evolving to a new super interglacial stage seasonally ice free, and this will have profound consequences for all the elements of the Arctic cryosphere, marine and terrestrial ecosystems and human activities. Both the atmosphere and the ocean circulation and stratification (ventilation) will also be affected. This raises a critical set of issues, with many important implications potentially able to speed up melting of the Greenland ice sheet, accelerating the rise in sea levels and slowing down the world ocean conveyor belt (THC). That would also have a lot of consequences on the ocean carbon sink (Bates et al. 2006) and ocean acidification. Permafrost melting could also accelerate during rapid Arctic sea-ice loss due to an amplification of Arctic land warming 3.5 times greater than secular 21st century climate trends, as pointed out recently by Lawrence et al. (2008). This permafrost evolution would have important consequences and strong impacts on large carbon reservoirs and methane releases, either in the ocean and/or on land.

This nicely encapsulates the big story — that Arctic warming is not just unfortunate for a few polar bears, it has consequences for the whole world. It’s especially bad news for Greenland ice sheet. NASA’s Earth Observatory reports that summer 2008 brought a record melt season for the far North of the island. Over at Yale’s e360, they explore the impacts of Arctic warming in an interview with Julienne Stroeve, who has been working on some of the climate and atmosphere responses to sea ice reductions.

So if you take that [summer sea ice] away you just start warming up the planet even more. And, we certainly would expect that to have an effect on atmospheric circulation around the planet, but exactly how that is going to manifest still remains quite unclear. The research on that is still very much in its infancy. But certainly, everything is connected, so when you change one component of the planet, the rest of the system is going to have to respond.

For a good overview of the work done in the Arctic over the IPY, The integrated Arctic Ocean Observing System (iAOOS) in 2008 report [PDF] covers everything — including fascinating insights on the gear being used (check out the Deepglider (p35); it can dive to 6km and travel 10,000km over 1.5 years before its batteries run down). There’s a lot of oceanographical detail, and plenty on ice, but the ecosystem section is also very interesting — particularly a sequence of maps showing the shift in zooplankton ecosystems around northwest Europe. In the 1960s and 70s warm temperate species just barely reached the tip of Cornwall — now they are found all the way round Ireland and Northwest Scotland, up to the Faeroes and beyond. You can also read about the voyage of the Yakov Smirnitsky, and see their maps of methane plumes in the seas over the Siberian shelf.

With more melting of ice and permafrost, the Arctic Ocean is experiencing significantly increased inflows of fresh water. This has been pooling in the central Arctic, but IPY research now suggests that the ocean is primed to dump a lot of low salinity water into the North Atlantic through the Fram Strait (between Greenland and Svalbard). The researchers are concerned that this could have an effect on deepwater formation in the region, which is one of the prime drivers of the global thermohaline circulation.

Down south, the most dramatic recent news is the mapping of the Gamburtsev Mountains in East Antarctica. Discovered by Russian scientists in the 1950s, little was known beyond the existence of a few peaks under 2.5 miles of ice. The Guardian reports:

“When we went out to the ice, we knew there was a potentially elevated region there, but we had no idea what it looked like,” said Fausto Ferraccioli, a geophysicist at the British Antarctic Survey who led the UK team within the international mapping project. “We now see that this mountain-range is the size of the Alps, but it looks like them too — it has all these fresh-looking peaks and valleys.”

Researchers constructed a map that revealed a mountain range at least 800km long and up to 400km wide, covering an area the same size as the Euopean Alps, at more than 200,000 square kilometres. Their survey also showed peaks of 3,000m above sea level and valleys down to 1,000m below sea level. The highest peak in the Alps, Mont Blanc, rises more than 4,800m above sea level but the valleys in this area are typically just 500m deep.

The “new” mountain range poses a challenge to geologists because it is located in the centre of a plate, and seemingly not built by the plate collisions responsible for both Alps, the Andes, Rockies and Himalaya. It might also be the place that where the Antarctic ice sheet began to grow, 35 million years ago. More at NatureNews (grab it before it disappears behind a paywall).

Of course politicians have to get in on the act, and a bunch of environment ministers have visited the Norwegian Troll research station earlier this week to learn about IPY efforts on the continent. Bad weather delayed their flight down south from Capetown, and the politicians were treated to talks by IPCC head Rajendra Pachauri and Lord (Nick) Stern. The latter was on gloomy form, telling his elite audience:

[…]if negotiators falter, if emissions reductions are not made soon and deep, the severe climate shifts and sea-level rises projected by scientists would be “disastrous.”

It would “transform where people can live,” Stern said. “People would move on a massive scale. Hundreds of millions, probably billions of people would have to move if you talk about 4-, 5-, 6-degree increases” – 7 to 10 degrees Fahrenheit. And that would mean extended global conflict, “because there’s no way the world can handle that kind of population move in the time period in which it would take place.”

Thanks Nick, that’s cheered me up no end. [Also at BBC]

There’s a huge amount of material to be published over the coming year based on IPY work, but one thing is already clear: the effort to work out what’s going on in the global cryosphere has to continue. We can’t afford to wait another 50 years for another IPY. By 2057-8 there might be little ice left to study…

(I’ll update this post with a link to the IPY overview report when it’s available.)

[Steely Dan]