Sunday, November 10, 2013

Typhoon Haiyan - Climate Change or Not?

Typhoon Haiyan's death toll may reach a staggering 10,000, which in population-adjusted numbers would be over 32,000 if it happened in the United States -- eleven 9/11s.

The usual suspects are working hard on their spin. HotWhopper has a good discussion of Anthony Watts' callousness, and then there's this jewel from Bjorn Lomborg;

https://twitter.com/BjornLomborg/status/399499537502310400

That's right -- it's immoral to think about how 10,000 deaths might have been prevented, this time or in the future, unless you think about it the way Bjorn Lomborg does. Wow.

Bill McKibben seems more restrained, twittering what's happening in the Phillipines but not directly linking it to climate change.

Andrew Freedman at Climate Central has a pretty good discussion of the storm from the perspective of a few hurricane researchers, and what the future might bring. 
Hurricane researchers contacted by Climate Central said Haiyan is an example of the type of extreme storm that may become more frequent as the climate continues to warm. But there is more consensus about the stormier future than there is about the present. The researchers also urged caution in attributing Haiyan’s strength to global warming, given the lack of evidence that manmade global warming has had any detectable influence on Western Pacific typhoons, let alone tropical cyclones in general (an umbrella term that includes typhoons and hurricanes).
The Guardian has a good article too, saying "a record seven typhoons developed across the west Pacific during October...."

It seems to me science just cannot yet quickly assess whether an extreme event is related to cliamte change or not -- it takes a lot of work afterward, and the verdict isn't always intuitively obvious. Mostly I say that based on the BAMS supplement "Explaining Extreme Events of 2012 from a Climate Perspective" published this September. They looked at 19 notable events that happened in 2012 from across the globe, and concluded that "approximately half the analyses found some evidence that anthropogenically caused climate change was a contributing factor to the extreme event examined...."

A great deal of scientific analysis went in to each event, and it seems difficult to guess beforehand which events had a link to climate change and which didn't. The central U.S. drought was not caused by climate change, they concluded, though it was made more severe because higher temperatures increase evaporation which decreases water availability. 

But a severe drought in the Iberian Peninsula did seem "partially driven" by climate change. The heavy rainfall over eastern Australia in March 2012 was found to be caused by "unforced internal climate variability." And so on. 

Global warming immediately comes up in the discussion of all these events. But careful analysis -- and only careful analysis -- that looks deeply at the event and its climatological context finds that only some of them were linked to global warming, and then only after a lot of work.

But to the extent that manmade climate change was a contributing factor to about half of the 2012 events, and there will doubtless be more in the future (even if we don't know which they will be), there is still a very good (some would even say moral) argument to be made for mitigation and not just adaptation. 

3 comments:

Dan Pangburn said...

Carbon dioxide change has never had a significant influence on climate and never will. Find out what actually has driven average global temperature at http://danpangburn.blogspot.com/

Chris_Winter said...

Dan:

Please post a note here when you win your Nobel Prize for disproving what 97% of scientists throughout the world believe about CO2 and its effects on IR emissions.

Chris_Winter said...

As far as I can tell, Bjorn Lomborg feels everything is immoral as a reason for cutting CO2.