Saturday, May 29, 2010

Mitigation vs adaptation: a question of prudence

For some time there has been a debate concerning the best response to the climate disruption human actions are currently causing. Should we try to minimise or even prevent the disruption (known as mitigation) or should we simple prepare for the changes and make adjustments as they arise (adaptation)? In other words, are we aiming for prevention or cure?

A good answer was given in a recent interview by John Holdren, science advisor to US President Obama:
“Mitigation alone won’t work because the climate is already changing. We’re already experiencing impacts from that. Nothing we can do in the mitigation domain can stop it overnight. And so a mitigation-only strategy would be insanity.

"Adaptation alone won’t work. Adaptation alone won’t work because adaptation gets more difficult, more expensive, and less effective the larger are the changes in climate to which we are trying to adapt. If you live on an island that is one meter above sea level and the sea level goes up two meters, adaptation is no longer the question. You are dealing with evacuation.

"Clearly what we need is enough mitigation to limit changes in climate to a level with which adaptation can largely cope.”
The question is whether we have the political and social will to do enough of the former in sufficient time to make the latter actually achievable.

Crucial in this is the role of the somewhat overlooked virtue of prudence, wise consideration of the future. Whether our political and economic systems are designed to encourage this virtue in our leaders remains to be seen.


byron smith said...

The interview also has a good four point summary of where the US administration understands the science to be at.

Gordon Cheng said...

Speaking of the science, the Royal Society seems to think it's a bit less settled than it was a couple of years ago.

Who would have thought? ;-)

Gordon Cheng said...

From the article, a quote from the Society's president:

Science is organised scepticism and the consensus must shift in light of the evidence.


byron smith said...

Absolutely - wait until they actually bring out the document and we'll see what it says, rather than what journalists expect it might say.

Here's part of the article Gordon mentioned.
Lord Martin Rees, President of the Royal Society, admitted that the case for man-made global warming has been exaggerated in the past.
He emphasised that the basic science remains sound but agreed to issue guidance so that it better reflects the uncertainties.
”Climate change is a hugely important issue but the public debate has all too often been clouded by exaggeration and misleading information," he said. "We aim to provide the public with a clear indication of what is known about the climate system, what we think we know about it and, just as importantly, the aspects we still do not understand very well."

Lord Rees said the new guide has been planned for some time but was given "added impetus by concerns raised by a small group of fellows".
"Nothing in recent developments has changed or weakened the underpinning science of climate change. In the current environment we believe this new guide will be very timely. Lots of people are asking questions, indeed even within the Fellowship of the Society there are differing views. Our guide will be based on expert views backed up by sound scientific evidence," he said.
That all sounds pretty good. Things have been exaggerated in both directions, though it is interesting to note who has been exaggerating and who is willing to correct their claims and/or shift their position when new information comes to light. There is so much confusion in the public about where there is still uncertainty (e.g. in the precise degree of climate sensitivity, the nature of dynamical ice flows and especially in the possible social and political responses) and where there is broad agreement (that the climate is changing, that anthropogenic GHGs are the primary forcing, that feedback mechanisms amplify the effects of this forcing, that even the most optimistic assumptions are still worrying and the worst deeply disturbing).

While we wait for the Royal Society to update their publication, we can read the latest report from the US National Research Council. Here is their conclusion: "Climate change is occurring, is caused largely by human activities, and poses significant risks for — and in many cases is already affecting — a broad range of human and natural systems". It bases that conclusion on "a strong, credible body of evidence, based on multiple lines of research [...] While much remains to be learned, the core phenomenon, scientific questions, and hypotheses have been examined thoroughly and have stood firm in the face of serious scientific debate and careful evaluation of alternative explanations."

byron smith said...

And here is the original source, which the Telegraph didn't bother to link to. The Telegraph piece makes it sound like they interviewed Rees, rather than just re-hashing the news page of the RS.

byron smith said...

A phrase I've heard numerous people use recently: we need to adapt to changes that are unavoidable and avoid changes that are unadaptable. That neatly puts Holdren's point.