Posts Tagged: albedo

This week’s top climate science links

Dive right in:

  • Will 2010 be the hottest year on record? – it all depends on which data source you choose: GISTEMP (likely) or HadCRU (about as likely as not).
  • Climate change is leaving us with extra space junk – Even the space junk is trying to tell us we’re changing the climate. One more independent line of evidence to add to the pile, how many do we need?!
  • Black Carbon’s Grey Areas – A brilliant, must-read article on black carbon. Who would have thought it has such broad geopolitical implications? Worth the effort. It’s conclusions: 1. Stop throwing cook-stoves at the problem. 2. Target diesel. 3. Be very careful about comparing black carbon with carbon dioxide.
  • Ocean acidification – still happening.
  • Arctic climate may be more sensitive to warming than thought – “Our findings indicate that CO2 levels of approximately 400 parts per million are sufficient to produce mean annual temperatures in the High Arctic of approximately 0 degrees Celsius (32 degrees F) [19 degrees Celsius warmer than today!],” Ballantyne said. “As temperatures approach 0 degrees Celsius, it becomes exceedingly difficult to maintain permanent sea and glacial ice in the Arctic. Thus current levels of CO2 in the atmosphere of approximately 390 parts per million may be approaching a tipping point for irreversible ice-free conditions in the Arctic.”
  • Network Rail study to assess impact of climate change – eco-stealth taxes are being used to… strengthen our vulnerable rail network, oh.
  • Troubling ice melt in East Antarctica – it’s losing mass, which is not good. – “It’s too early to know what the ice loss in East Antarctica really means, says Isabella Velicogna, a remote-sensing specialist at NASA’s Jet Propulsion Laboratory in Pasadena, California. “What is important is to see what’s generating the mass loss,” she says. Reductions in snowfall, for example, might reflect short-term weather cycles that could reverse at any time. But thinning caused by accelerating glaciers—as seen in West Antarctica—would warrant concern.”
  • Peru inventor ‘whitewashes’ peaks to slow glacier melt – In a remote corner of the Peruvian Andes, men in paint-daubed boilersuits diligently coat a mountain summit with whitewash in an experimental bid to recuperate the country’s melting glaciers. Peru’s Environment Minister Antonio Brack has said the World Bank’s 200,000 dollars in funding would be better spent on other “projects which would have more impact in mitigating climate change.” “It’s nonsense”, he commented bluntly last year.
  • Leakegate: A retraction – “It is an open question as to what impact these retractions and apologies have, but just as with technical comments on nonsense articles appearing a year after the damage was done, setting the record straight is a important for those people who will be looking at this at a later date, and gives some hope that the media can be held (a little) accountable for what they publish.”

And finally, on a slight tangent:

  • Ben Goldacre: Yeah well you can prove anything with science – “When presented with unwelcome scientific evidence, it seems, in a desperate bid to retain some consistency in their world view, people would rather conclude that science in general is broken. This is an interesting finding. But I’m not sure it makes me very happy.”

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!