But we do know with high certainty that human activities are already changing climate. The high-confidence attribution of even the very small amount of warming already experienced to partly human causes, is really a key recent step forward in the science whose importance is often underappreciated by lay observers. The amount of warming experienced so far is of course very small, but together with the inertia of the climate system, it tells us with high confidence that if we continue on our current path climate change will be much much larger in the future. In fact, we do know quite a bit (even if not everything) about the feedbacks, and the part we don’t know could just as easily make things worse as make them better.

As my colleague Dan Schrag writes in a Boston globe op-ed posted here on the thread about Congressional hearings,

“In public lectures, I show pictures of what would
happen to Florida and the Gulf Coast if half the
Greenland Ice Sheet melted, asking people to
imagine abandoning New Orleans and Miami. I tell
people that, unless we take action to reduce
emissions, the question is not whether this is
going to occur, but when.”

This is largely the nature of the remaining uncertainties we face: not if, but when. I can understand why you might want to latch onto the appealing hope that somehow negative feedbacks, a la Dick Lindzen’s high atmosphere water vapor feedback of 20 years ago, will rescue us. But the science has advanced a lot in the last decade or two, and it just doesn’t look like it is in the cards. Continuing to hold onto the “feedback rescue” scenario in the face of what we now know is a little like the Bush administration saying that it is going to win in Iraq: fond hope, but little basis in reality.

Best,
Scott

Does James Hansen or anyone else think it won’t be “a different world” in 2100 compared to 2000, even if there was no climate change at all?

Virtually all people in 1900 would never have seen electricity, an automobile, or an asphalt road, let alone radio, TV, air conditioning, a computer, the Internet, a mall, a microwave, etc. etc.

And the changes from 2000 to 2100 are likely to absolutely dwarf the changes from 1900 to 2000. Human-machine cyborgs (or even no bodies at all). Immortality. Sufficient wealth that no one need ever work a day in their life.

To think that it wouldn’t be absolutely trivial in such a world to produce whatever CO2 concentration was desired doesn’t show much appreciation for humans’ (or successors) ability to manipulate the environment.

It could, but nobody knows that, because of feedback unknowns. Sometimes people too close to the work can’t see the forest from the trees.

Plus, returning to the temperature trajectory from the MWP peak to the LIA valley when anthropogenic effects potentially started making a difference could be more of a detriment.

What is optimum? The temperature when the Luddites were demonstrating? How about the average over the last hundred thousand years? Maybe what has typically been described as the Holocene Maximum, aka the Climatic Optimum?

I think we’re talking about different things here. My questions are informed by a recent development in tech policy that’s perhaps better as a separate post.

What I was thinking when talking about addressing political implications is to say that certain policy recommendations or research conclusions would have particular political implications or have a particular political impact (group x or Senator y would oppose implementing something or disagree with the conclusion).

I think (and could very well be wrong) that suggesting a political impact of a research conclusion isn’t necessarily the same thing as advocating a political position from the strength of a research conclusion. In my mind, the former is adding a degree of analysis to the problem, the latter is working the wrong side of the is/ought problem.

I think the connection Ryan raised between the broader impacts criteria and scientists considering political implications is interesting. Personally (and perhaps colored from my having at most one foot in academe), I think researchers at least acknowledging broader impacts (whether societal or political) shows a level of self-awareness that would be encouraging. The care that must be taken is to talk in terms of possibilities rather than requirements. Saying that these things could happen is different from saying that they will, should or must.

And no, none of this will help us get at Gore’s intent with his remarks, but it still raises useful issues.

1. For a modern-day Man in the Iron Mask, Hansen sure gets around, and in front of a lot of microphones.

2. If Gore truly believes what he says, then he will not allow democratic politics to interfere with his mission. If activist-scientists can persuade the public to accede to his and their policy leadership, so much the better. If not, then democratic politics must be sacked because saving the Earth is inestimably more important than preserving democracy.

3. Public support for action on climate change is premised on each of the following assumptions about policy:

(a) WHAT “MUST BE DONE” IS NOT CLEARLY SPECIFIED. Support for action dissipates the clearer advocates are in specifying the nature and practical consequences of proposed action.

(b) IF IT COSTS A LOT TO ACCOMPLISH “WHAT MUST BE DONE,” SOMEONE ELSE WILL PAY FOR IT. Polls do not reveal willingness to pay on the part of the respondent. At best, they reveal the willingness of the respondent for someone else to pay.

(c) “WHAT MUST BE DONE” WILL NOT GET IN THE WAY OF MY STANDARD OF LIVING. Like recycling, people are willing to make token sacrifices in pursuit of environmental purposes. Few will accept a 40% reduction in their energy use.

Does anyone who follows Gore more closely know what specific policies he recommends, and whether those policies are commensurate with his characterization of the magnitude of the problem? Offline replies are welcome.

Hansen for his stating on television the absurd idea
that half the species on the planet could go extinct from CO2 warming.

Gore for indicating that glacial CO2 temperature
correlations are significant to current times when
well read scientists know that temperatures led CO2
and that it was more likely glacial circulation
than temperature which modulated CO2.

Back to your “deficit model” question: I am not familiar with the social science literature on this, and I am sure that there are insights there from which I would benefit, but I have no doubt that you are right that some scientists and politicians espouse a view of the relation between public understanding and policy action that is highly caricatured.

However, I think your question mostly misses the point:

You wrote:

“Do you really think that if the public really understood the complete details of the IPCC that they’d change their political views and behavior? Any evidence for this?”

The point is not that the public needs to understand the “complete details” or needs a more sophisticated knowledge base. I am concerned, at bottom, about two things in this arena:

(1) if the Pew poll is right, the public does not grasp the policy relevant science fundamentals: that human emissions are causing global warming now, that this problem will get much worse in the future, and that early and sustained abatement actions can substantially address the problem. The “complete details” do not matter nearly so much as these fundamentals. Here the science is compelling, and highly policy relevant. That there is some background natural climatic variation is true, but not very relevant to the policy. (the background variation does not constitute a trend towards, in Hansen’s memorable phrase, “a different world”; human climate change does).

(2) If the Pew poll is right, the public intensity of support for policy action on climate change, through broad, is shallow. This makes it a non-factor politically for those (like the current leadership) who want to do little or nothing. If the lack of intensity is attributable in part to confusions about the fundamentals (i.e. belief that climate change is mostly natural, or that the scientific community does not understand it very well), then it seems to me that a more widespread understanding of the fundamentals (not the details) could make a difference.

An issue of this magnitude needs more than broad support expressed in public opinion polls, it needs a campaign for action. There are many aspects of such a campaign, but one of them is surely a common perception that shared values are at risk. Global warming puts at risk environmental values that polls show are widely shared by the American public, but if Pew is right on point 1, the public is confused about the fact that changeable human activities are what is posing the risk.

Best,
Scott

Let me offer an unsolicited 2 cents on your question to Ryan.

If indeed Gore was encouraging scientists to discuss “political implications” of their research, then he was at the wrong meeting. He should instead be taking to political experts, not climate experts. In fact, he is far better positioned to discuss political implications than his audience was. While encouraging the politicization of science is not necessarily a bad thing (remembering that politics is how we get done the business of society), encouraging the AGU membership to politicize science is something that requires some care.

Thanks!

I agree with this. But what is it that qualifies a scientist to communicate political implications? The same might be asked in regard to “broader impacts” claims required of NSF grant applicants.

Gore did not get into specifics on this, so it is difficult to say that he “made the leap” as you suggest. Also, it’s difficult to intuit just what he means by “implications.” We often see arguments on this blog for the communication of policy options. How does this compare with the communication of political implications? we could certainly argue the semantics of this, but it wouldn’t give us further insight into just what Gore was calling for.