Some Views of IPCC WGII Contributors That You Won’t Read About in the News

April 18th, 2007

Posted by: Roger Pielke, Jr.

I was surprised to read in E&E News today a news story on yesterday’s hearing held by the House Science Committee suggesting that the take-home message was that adaptation would be difficult, hence mitigation should be preferred (for subscribers here is the full story). My reading of the written testimony suggested a very different message, and not one I’ve seen in the media. Below are some relevant excerpts from IPCC WG II authors who testified yesterday (emphasis added). I know both and respect their views.


Roger Pulwarty (PDF)

Climate is one factor among many that produce changes in our environment. Demographic, socio-economic and technological changes may play a more important role in most time horizons and regions. In the 2050s, differences in the population projections of the four scenarios contained in the IPCC Special Report on Emission Scenarios show that population size could have a greater impact on people living in water-stressed river basins (defined as basins with per-capita water resources of less than 1000 m3/year) than differences in emissions scenarios. As the number of people and attendant demands in already stressed river basins increase, even small changes in natural or anthropogenic climate can trigger large impacts on water resources.

Adaptation is unavoidable because climate is always varying even if changes in variability are amplified or dampened by anthropogenic warming. In the near term, adaptation will be necessary to meet the challenge of impacts to which we are already committed. There are significant barriers to implementing adaptation in complex settings. These barriers include both the inability of natural systems to adapt at the rate and magnitude of climate change, as well as technological, financial, cognitive and behavioral, social and cultural constraints. There are also significant knowledge gaps for adaptation, as well as impediments to flows of knowledge and information relevant for decision makers. In addition, the scale at which reliable information is produced (i.e. global) does not always match with what is needed for adaptation decisions (i.e. watershed and local). New planning processes are attempting to overcome these barriers at local, regional and national levels in both developing and developed countries.

Shardul Agrawala (PDF)

The costs of both mitigation and adaptation are predominantly local and near term. Meanwhile, the climate related benefits of mitigation are predominantly global and long-term, but not immediate. Owing to lag times in the climate system, the benefits of current mitigation efforts will hardly be noticeable for several decades. The benefits of adaptation are more immediate, but primarily local, and over the short to medium term.

Given these differences between mitigation and adaptation, climate policy is not about making a choice between adapting to and mitigating climate change. Even the most stringent mitigation efforts cannot avoid further impacts of climate change in the next few decades, which makes adaptation essential, particularly in addressing near term impacts. On the other hand, unmitigated climate change would, in the long term exceed the capacity of natural, managed, and human systems to adapt.

4 Responses to “Some Views of IPCC WGII Contributors That You Won’t Read About in the News”

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  1. Lab Lemming Says:

    So is the idea of using carbon pricing (tax or credits) to pay for adaptation not on anyone’s agenda? Have there been any realistic, tractable conservative solutions to climate change suggested?

    Just wondering.
    -LL

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  3. Simon Donner Says:

    Straw man aside here, the use of those quotes, especially the first highlighted line from Dr. Agrawala, is a bit disingenuous. The message “that adaptation would be difficult, hence mitigation should be preferred” obviously depends on the time frame. Of course, the effects of mitigation won’t be felt for some time. And of course, some adaptation is necessary, as there has already been some warming and some further warming is unavoidable given the aforementioned lags.

    Adaptation by social and ecological systems to this committed warming, or to warming under a stabilization at a doubling of CO2 scenario, is clearly more plausible and more affordable than adaptation to a 3-4 C warming. A ‘preference’ for mitigation now simply recognizes that actions today dictate the emissions path, and whether we’ll face the unenviable and for many impossible task of adapting to a 3-4 C warming. Dr. Agrawala’s final sentence should be highlighted: without mitigation now, adaptation may become impossible

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  5. Mark Bahner Says:

    “Adaptation by social and ecological systems to this committed warming, or to warming under a stabilization at a doubling of CO2 scenario, is clearly more plausible and more affordable than adaptation to a 3-4 C warming.”

    I don’t understand. The IPCC AR4 “best” estimate of warming from a doubling of CO2 ***is*** 3 degrees Celsius.

    So if 3 deg C is the IPCC’s best estimate of the warming from a doubling of CO2, how can adaptation to stabilization at a doubling of CO2 be “clearly more plausible and affordable” than adaptation to 3 deg C warming?

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  7. Roger Pielke, Jr. Says:

    Simon- Thanks for your comments. had the E&E article said anything remotely as nuanced as you did it’d be a different story:

    “Of course, the effects of mitigation won’t be felt for some time. And of course, some adaptation is necessary, as there has already been some warming and some further warming is unavoidable given the aforementioned lags.”

    It said nothing of the sort. Thanks!