I have a climate change skeptic in my family who is a geoscientist. He recently sent me some work on the science of glaciation where ice core samples serve as bases for measuring climate shifts. Studies of oxygen-isotope variations suggest that we may have passed the maximum warmth in our current interglacial period. Glacial-interglacial periods tend to run about 100,000 years. We have been in an interglacial warming period since the last "ice age" and, some studies suggest, are now actually on the down-swing. From the perspective of geologic time, in other words, climate change doesn't look so bad and may not even be true, at least based in studies of glacial-interglacial cycles. Of course, understanding climate change is more complex than understanding glaciation itself.
Now, this is from someone who is not only a skeptic in terms of the science - which is generally a good thing in the sciences - but also on the political right. There's thus a further, political purpose in sending me the data writeup. And, as with most of this debate, I detect confusion.
Here's the question, and I think this is crucial to ask regarding the massive issue of climate change: what's the problem?
Here's how I answer this question. Climate change in itself - that is, the brute shift in climate, which has occurred for millions of years - is not a problem at all but a matter of scientific fact. Now, the facts can be disputed since scientific understanding of climate change possesses a fair degree of uncertainty and is obviously incomplete. Facts are disputed when different scientists come up with different data sets suggesting different explanations of what the overall climate is generally doing. They may also be in dispute when different scientists, analyzing the same data sets, develop different interpretations of what the data means. This is one level of the "problem" of climate change, and it is a perfectly appropriate one. A certain amount of skepticism is usually a good thing in science (and other endeavors) because, if nothing else, it can help to flesh out a more precise understanding of reality.
Climate change analysis and understanding obviously requires good science and some degree of consensus. It turns out that we're at that point and have been for some years. Scientific skepticism regarding climate change now involves matters of degree rather than matters of kind (and see the graphs I posted earlier here). There's much talk of "politicization" of climate change (see a review of Lomborg's new book here, for example), but this has less to do with the nature of the scientific consensus and more to do with various other interests interpreting the science for reasons outside of the science itself. Lomborg and others criticize people like Al Gore, the IPCC, and some environmental activists for sensationalizing the coming harms of climate change. Exxon-Mobile funds a political program designed to build a public perception of climate change as not an issue at all. And various politicians use the issue for their own needs. Further, some scientists themselves interpret the data through the lens of their own political, economic, and social values. Sometimes this can radically distort the science itself, although my own view is that value questions are never far-removed from questions of fact (actually, as a philosopher I question the whole distinction) because fact doesn't exist on its own but is always by its very nature interpreted through an epistemological and axiological background framework that is inherited and has little (or everything!) to do with the facts at hand.
This is largely how the "debate" over climate change takes place in the US public discourse. That is, a bunch of people driven by other political and economic concerns interpret the current state of scientific understanding in terms of their own short-term and short-sighted purposes and interests. Some do so wildly and deceitfully, while all do so to some extent. And these interests are often not the public's interests at all. My own view is that this kind of "politicization" is not a phenomenon of the right or of the left in particular, although the Bush administration's eight years of willful ignorance has put the ball in the right-wing court. Basically, politicization in this sense is a battle over self-interest, even if these self-interested entities seek to portray their cause as in the public interest (which is basic political maneuvering - make the particular appear to be universal).
What is the problem of climate change? It is political, as well as economic and moral. Again, the scientific understanding of climate change as a collection of hydro-meteorological phenomena - that there is a rapid warming trend - is not the problem in itself. The problem of climate change only arises as a problem when we look to the effects of climate change on human and nonhuman animal populations. Rising or receding sea levels, for example, are nothing in themselves but hydro-meteorological phenomena. They're only problematic when human populations live in low sea-level coastal areas and may find their lives uprooted, and their land and livelihoods are destroyed.
So, the problem of climate change is in its effects on human and animal populations. The question is clearly an economic one at this point. But it's also a moral question. That is, given that the negative effects of climate change are variable across countries and across different populations within countries, and given that the poor are affected disproportionately, are those in better conditions obligated to assist those who are and will be negatively affected? A powerful affirmative case can be and is made, although I won't go into it here for now. Any genuine assistance will involve massive financial, technological, and human resources. The question then centers on the degree of assistance by countries and organizations in a position to help. This in turn demands political will and political honesty. In other words, climate change in this sense is a problem of distributive and procedural justice. I'll have more to say about this later, but it is a problem of the distribution of resources, and a problem of the fairness of decision-making institutions. This is the basic problem of climate change.
Now, notice that nothing in this discussion thus far is connected to anthropogenic climate change. It can be established quite clearly, I think, that there is an obligation to assist the vulnerable through the development of mitigation and adaptation strategies without ever entering into discussion of anthropogenic climate change. And, of course, if climate change is anthropogenic - generated by human activity - then it's incumbent upon probably all of us, for the sake of ourselves and future generations, to change our practices. It is also possible to change our own activity.
The science on anthropogenic climate change is more disputed by scientists than climate change in general, but we've moved more recently towards a fairly strong scientific consensus even on the anthropogenic features. Yet, given the relatively higher degree of uncertainty, there is more to exploit politically. This is precisely what the Bush administration has done over the past seven years ("more research is needed"), but also in a context of Chinese industrialization and other geopolitical, economic considerations.
Here's the rub. If anthropogenic climate change is fully established and the physical processes (that is, greenhouse gas emissions) by which it occurs are clearer, then it is possible to determine historical responsibility for emissions levels. That responsibility, of course, falls largely on the US, the largest emitter in the world. And, before you complain, note what I wrote earlier,
China, today, is the second largest carbon dioxide emitter, but only if measured by absolute emissions for the country. Per capita emissions remain quite low (Americans are responsible for five times the CO2 emissions per capita), although they are rapidly rising as China's economy continues to boom and produce a mass-consumer class. Nevertheless, the vast majority of Chinese remain poor - poverty entails lower consumption, which entails less pollution, at least per capita.The issue of historical responsibility shifts the nature of the problem. As a matter of harm in which a few countries have benefited economically from GhG emissions while others have suffered and are largely not responsible, places a much different set of variable moral obligations on the issue of climate change. Countries like the US and China know that taking up these obligations entails serious changes to their own economies and/or lifestyles. Thus, national self-interest in the face of real harms to others becomes the problem of climate change.
But there are also different ways to look at responsibility for burden-sharing. Historical responsibility for emissions is one. But we can also use other approaches such as grandfathering (as with the Kyoto Protocol, tracing back to a baseline year of emissions), carbon intensity, and per capita emissions. Each of these approaches has different justifications and different interests involved. For example, a United States acting on its own interests is not about to use per capita emissions as a burden-sharing approach because Americans emit five times the carbon dioxide as China, for example.
If we're agreed that climate change exists (which scientists do), if we're also agreed that climate change is to a significant measure anthropogenic (which scientists increasingly do), and if the problem of climate change is in its effects on human and animal populations (which is basic to the problem), then the fact of variable effects hitting poor peoples in particular who are largely not responsible for the emissions, and the historical responsibility of the large industrialized nations, indicate that the problem of climate change is, yes, entirely moral and political.
UPDATE (9:44pm, 1/14):
See also, Escalating Ice Loss Found in Antarctica: Sheets Melting in an Area Once Thought to Be Unaffected by Global Warming
By the way, a blog called "Greenie Watch" (with the url, "antigreen") has linked to this post. Welcome, folks. But it's curious to me that the linking post is called "Cooling Coming?" This seems to me to confirm my point about people taking up climate claims for their own political purposes. My post is hardly about a cooling climate. I hope that you readers will take the time to read the entire post, rather than simply the first paragraph.
UPDATE - September 2009:
See Cheryl's excellent post here explaining how and why measuring climate change (or global warming) and understanding the problem go way past referring to one disputed indicator, such as glaciation.