Wednesday, March 29, 2006



Climate Change & Governance: Tuesday Morning

The first day of the Climate Change and Governance Conference focussed on the science. Here's a rundown of what was covered in the first session:

Professor Peter Barrett (VUW) spoke about the long-term climate record, as seen in the geological record. 65 million years ago, the Earth was 6-10 degrees warmer, and CO2 levels were significantly higher than pre-industrial levels. Since then, there has been a long-term cooling trend, mirroring and mirrored by a long-term decline in CO2. We now seem to be reversing that trend. Particular attention was paid to the record of the growth and shrinking of the Antarctic ice-cap, which fluctuates in the long-term according to the Milankovitch cycles, with CO2 tracking the change within a certain natural band. We are now well outside that natural band of fluctuations, with a CO2 level unprecedented for at least a million years. This is expected to produce climate change not seen since the age of dinosaurs.

Dr Dave Lowe (NIWA) spoke on the changing composition of the atmosphere and the atmospheric greenhouse gas record. He first talked about the Keeling curve - that lovely set of measurements of atmospheric CO2 from Mauna Loa - and then his own data collected over the last 30 years from Baring Head near Wellington. The upward trend in atmospheric CO2 concentration is consistent across multiple data sets and increasing; the long-term growth rate was a mere 0.5 ppm/year when measurements first started, and is now 2 ppm/year (with Baring Head showing 2.5). It tracks the increase in fossil fuel use, and isotope studies show that that is very definitely where the carbon is coming from. what's frightening is that fossil fuel use continues to increase at 2% a year.

Professor David Vaughan (British Antarctic Survey) talked on Antarctic de-glaciation and the global climate system, and particularly about the Antarctic Peninsula and West Antarctic ice shelf. While other parts of Antarctica are cooling and thickening, the Antarctic Peninsula has warmed significantly, and 87% of the glaciers in the area are in retreat - a change which does not seem to be part of any natural cycle according the geological record. More concerning, the West Antarctic ice sheet is thinning, and would need to thin only a little more in order to float free of the seafloor and break up, causing significant sea-level rise. Studies of the underlying geology show the areas this is likeliest to occur, and all they can do is watch. Vaughan made the point that while in the developed world sea-level rise will simply cost money (on flood defences, seawalls etc), in the developing world it will kill, as these societies simply lack the resources to cope with or protect against it.

That's all for now; maybe I'll post more later, when I've had a chance to digest it all.

8 comments:

I had been searching the web for a brief rundown of the conference and had so far failed to find anything, so thanks for providing us all with this.

It is all highly frightening stuff, based on decades of credible science. What makes it worse is that we know it's happening, but that so far we refuse to do anything about it. New Zealand is currently not helping at all with the scrapping of the carbon charge.

Posted by Peter Wilson : 3/29/2006 10:37:00 AM

I think I tracked down to source of climate change - climate change scientists flying all over the word to climate change conferences.

Posted by Anonymous : 3/29/2006 10:42:00 AM

anon,

I was given an amazing statistic six years ago when I lived in the USA: at any random time during the average day there are probably 100,000 people in the air flying over the USA, or to or from the USA.

Given that many business travellers fly several times a week, and I've known people who commute home for weekends by plane, and a population of a quarter billion, it seems believable but a bit high.

If anyone has hard data to prove, disprove or improve that 100,000 figure I'd be interested.

Posted by Icehawk : 3/29/2006 12:28:00 PM

I was meant to be at both days of the conference via a press pass from Aotearoa Indymedia, and was planning on doing some fairly in depth reporting from there, however life has got in the way and I have been far too busy to even attend the conference. I'm pretty gutted, as I was looking forward to it for a while...

Posted by Asher : 3/29/2006 01:58:00 PM

Oh the bright side, all the talks are being recorded and audio will be available in the near future.

Posted by Asher : 3/29/2006 03:46:00 PM

100,000 is only a couple of hundred full 747s... sounds reasonable to me.

A million year CO2 level increase is worrying when you consider that a mere 20,000 years ago sea level was more than a hundred meters lower than today. The potential sea level increase could easily be more than the developed world could handle. _Complete_ melting of the West Antarctic ice sheet alone would raise sea level by about 8 meters, and god know what that would do to the weather systems and the ice that makes up the other 70 meters or so of potential sea level increase. New Orleans is no more than 4 meters below sea level, and keeping that dry is apparently beyond the capabilities of the US.

Posted by Commie Mutant Traitor : 3/29/2006 04:06:00 PM

Anon: international air travel is indeed a growing source of CO2 emissions - but not in this case. The conference offset all its emissions, including those of flying its guests in from overseas, by buying credits from EBEX21.

Posted by Idiot/Savant : 3/29/2006 07:30:00 PM

Asher: I saw a couple of Inymedia people around, and I'm kicking myself for actually paying to attend rather than trying to scam a press pass as a blogger.

Maybe next time...

Posted by Idiot/Savant : 3/29/2006 07:34:00 PM