Some scientists aboad the Canadian research icebreaker Amundsen are predicting that the North Pole may be ice-free for the first time in recorded history this summer. While this is not the same as saying the whole icecap will be gone, it does seem like the sort of thing likely to have symbolic resonance. At the very least, it becomes a bit harder to argue that no overall warming is taking place when huge chunks of the cryosphere start to vanish.
While there are good reasons to doubt whether this year will really see the pole bare, it is only really a matter of time:
[G]iven the rapid changes now evident in the Arctic, the ultimate fate of the North Pole—in fact, all permanent ice in the Arctic—may be all but assured. Almost all models have the Arctic completely ice free in the summer by 2100.
This raises some worrisome questions. If the sea ice is being lost at a greater rate than anticipated, is that likely to carry over to Greenland? If so, the optimistically low estimates for sea level rise published by the IPCC may prove grossly inaccurate.
Scary
CBC Newsworld Host Harry Forestell: Well, at the G8 Summit today, leaders endorsed a new plan to cut greenhouse gas emissions in half by 2050, and this time the United States and Russia are both on board. But almost as soon as the
announcement was made, environmentalists began criticizing it. That’s because the plan doesn’t set a base year, and it doesn’t have any interim goals. As well, it isn’t a binding agreement for a country. Many climate experts warn global temperatures will increase by a full 2 unless firm action is taken. Andrew Weaver is a Canada research chair in climate models and analysis at the University of Victoria. He joins me now. Andrew, good to see you. Why is this figure (inaudible) so crucial? It doesn’t seem like a lot.
climate scientist Andrew Weaver: It’s 2 prior to since pre-industrial times. So it’s really 1.3 further degrees. The reason why it’s coming out — emerging as a number to not avoid is because as the number of key thresholds beyond that
warming we pass, one of them, for example, is it’s thought that beyond 2 we commit Greenland to its inevitable demise, meaning we’re committing ourselves to 6 metres of sea level rise. Similarly in west Antarctica, there’s some thought we may be committing to 6 metres further sea level rise. Ecosystem extinction at around that temperature.
CBC Newsworld Host Harry Forestell: 2 becomes almost, to use the phrase, a tipping point.
climate scientist Andrew Weaver: It’s a slow extinction of these species,
but 2 is a target that we’re trying to avoid, yes.
CBC Newsworld Host Harry Forestell: How close to that target will this 50% cut that the G8 has committed to get us? How close to that target will it get us?
climate scientist Andrew Weaver: The key point about this is there’s nothing
between. Let’s suppose we take the tarsands in Alberta, for example, and we quadruple production over the next 20 years and then we actually move down towards our 50% reductions on. This isn’t a good thing because where 50% reductions actually starts to matter is if we start to reduce today. So the fact that we’re missing these interim targets is a real problem because we can keep going up before coming down.
CBC Newsworld Host Harry Forestell: So is this promise satisfactory if it means 50% reduction in greenhouse gas production from this point forward?
climate scientist Andrew Weaver: If it’s on the path towards carbon neutrality, this is a good agreement because what we do know from the international
community is that in order to stabilize our levels of greenhouse gases and, hence, global temperature at any value, we must move towards carbon neutrality eventually. So 50% is a good way on the way, but we’ve got to go down from here, not up, way up, and then down.
CBC Newsworld Host Harry Forestell: Sure. Would you say what the G8
leaders have agreed to today is maybe a good intention but still falls short of what’s needed?
climate scientist Andrew Weaver: I’ve been asked whether this is good news or bad news, and I think it’s neither. It’s sort of news but, come on, how are we going to get there? Enough aspirational targets. Enough making targets 50 years from now. There’s not a lot of credibility to a target that’s being made by politicians once they are long and buried in the ground. This is not something that
they will ever be held accountable for because every one of them will probably not be around then. Let’s get something closer.
Ice bet
Arctic sea ice declines sharply in August
Posted by Joseph Romm (Guest Contributor) at 6:35 PM on 12 Aug 2008
The National Snow and Ice Data Center reported Monday that in the first 10 days of August, Arctic sea ice extent declined one million kilometers. Sea ice is now disappearing on a daily basis nearly 50 percent faster than it typically does this time of year.
Is the Cryosphere Crying Wolf?
What Arctic sea-ice levels can tell us about global warming.
By Nina Shen Rastogi
Posted Tuesday, Feb. 10, 2009, at 7:01 AM ET