Posts Tagged: arctic

This week’s top climate science links

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This week’s top climate science links

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  • Climate Change: A Threat to Global Security. US & UK Defense agree. – “I am struck by how similar UK and U.S. thinking is on the national security implications of climate change. Our defense departments agree that the impact of climate change is likely to be most severe in areas where it coincides with other stresses, such as poverty, demographic growth, and resource shortages: areas through which much of the world’s trade already passes.”
  • A Superstorm for Global Warming Research – a terrible terrible piece from Der Spiegel, who are usually pretty good at science reporting. Two of the authors have previously written some very misleading and inaccurate articles on climate change. Watch this space for updates…
  • Visualizing Arctic Sea Ice Extent Trends – “If you find yourself asking “what about … or what happens when…”, it’s probably time to make another chart that directly addresses your new “compared to what” question. Don’t expect one chart to answer multiple questions.”
  • Arctic ice recovers from the great melt – Wow, a semi-decent piece by Jonathan Leake! Apart from wrongly attributing the recent ‘spurt’ in ice growth to the Arctic Oscillation (it was more likely just a response to changes in regional atmospheric circulation) it’s a measured and almost insightful piece… is something weighing on his mind perhaps?

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This week’s top climate science links

Dive right in:

Read more

This week’s climate links

Dive right in:

Read more

This week’s climate links

Dive right in:

Read more

Melting compost heaps and the permafrost precautionary principle 1

Thawing permafrost could inject enough carbon into the atmosphere to cook the planet. But nobody’s quite sure how fast it’s going to happen.

Permafrost is a giant cold-storage compost heap, stuffed full of frozen carbon. Just like you chucked out last night’s potato peelings, the planet has chucked out billions of tonnes of dead plants, trees, mammoths and, yes, polar bears, all of which is now happily interred under the Arctic wastes.

The difference is that while your compost heap ticks over at a nice warm temperature, breaking down the potato peelings into compost, the frozen ground which makes up permafrost stops that organic stew of Arctic flora and fauna from decomposing, safely locking up the carbon stored in it.

I say ‘safely locking up’ because from the point of view of creating human civilisation, permafrost has been pretty handy. While the permafrost has been permanently frozen, we’ve been busy ekeing out human life, discovering fire, developing agriculture, growing our population. While we’ve been busy nurturing the capabilities that ultimately allow the lucky few to participate in Britain’s Got Talent, the planet’s been watching our backs by keeping this massive store of carbon locked up under the frozen parts of the planet’s surface. Read more

July Arctic Sea Ice Outlook

The Arctic Sea Ice Outlook has just been updated for July. It”s based on a synthesis of 16 estimates which utilise a range of different projection methods. They note that there is “no indication that a return to historical levels will occur”.

Big surprise!

The full range of estimates range from 4.0-5.2 million square kilometers, the record low in 2007 was around 4.3 million square kilometres (2008 was 4.7). Most estimates therefore fall between the record lows in 2007 and 2008, although they do note that:

There appears to be about a 20% chance of reaching a new minimum in 2009.

Arctic Sea Ice Outlook (July)

On the flip-side, based on their estimates there is a 40% chance of sea-ice coverage being greater than 2008 levels. Even more interestingly, depending on which method you select, the chance of 2009 levels setting a new record is between 5-36%...

Picture 4

To quote from the summary:

The two lowest estimates, 4.0 and 4.2 million square kilometers, would represent a new record minimum. All estimates are well online casino below the 1979–2007 September climatological mean value of 6.7 million square kilometers. The uncertainty / error values, from those groups that provided them, are about 0.4 million square kilometers, thus many of the values essentially overlap.

Although the majority of the responses indicate either persistent conditions or a slight increase over the 2008 sea ice extent, there appears to be about a 20% chance of reaching a new minimum in 2009. The September 2009 extent, as we track it for the rest of the summer, will depend on several factors, including the dynamics of the relatively high levels of thin, first year ice; temperature and wind conditions; and sea level pressure.

The report confirms the importance of first-year ice (FYI):

Multi-year sea ice has been reduced to such low levels that the overall September sea ice extent is largely tied to the fate of the first-year sea ice, which appears thin or with low concentrations away from the central Arctic. Depending on August conditions, much of this first-year sea ice could either melt out by September or survive the summer as a vast expanse of thin sea ice.

Accounting for their low 4 million square kilometre estimate, Rignor et al commented that:

In comparison to 2007 and 2008, there is much more first year (FY) ice in the Beaufort and Chukchi Seas in 2009, which we expect to precondition thisarea for a more extensive retreat than in 2007 and 2008.

Place your bets in the comments below, the winner gets a free trip to the PIRC office in sunny Machynlleth, mid-Wales!

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