I have to deliver a lecture next week in Minnesota on Catholic social thought on the environment ( a topic dear to me). Checking the weather reports for that area, I have noticed a high unseasonal warmth. But I know, of course, that climate is not weather. We can have overall global warming or cooling yet find, during a warming or cooling period, unseasonal opposite effects in some parts of the globe. Clearly, getting clear on climatology takes some careful parsing of data.
I turned to the excellent book by Michael Mann, The Hockey Stick and the Climate Wars: Dispatches from the Front Lines (Columbia University Press, 2012) for some illumination about the conflicting claims about global warming. Mann is a renowned climatologist at Pennsylvania State University. He is the one who coined the famous metaphor about global warming, the hockey stick. Using proxy data to chart temperature fluxes across a thousand year period, Mann likened the recent, late twentieth century rise in global temperature to a hockey stick, with a rough equivalent handle which showed mainly stability, giving rise, then, to a sharp rise in termperature like the blade of the hockey stick. By proxy data, Mann points to evidence from tree rings, ice bores, lake and ocean sediment and coral reefs to find indications of temperature over time.
Mann knows well that these proxy data must cover the entire globe. For, it is perfectly possible for parts of the globe to be heating while others have cooler than usual weather, for a net stability. He has also very carefully followed the data about solar intensity and volcano eruptions ( the latter lead to short term cooling in temperature). In point of fact, given the trajectory of these last two items, the earth's temperature should be cooling now rather than heating up. The decade of the 1990's, as it turns out, however, was the warmest decade in six centuries. Climate skeptics vigorously attacked the image of the hockey stick rise in temperature as a "fluke" in statistical reasoning rather than any indication of true data.
Reading Mann's book, I was puzzled that anyone would really be in denial about climate change. In truth, one might be skeptical about one or other policy proposal to deal with global warming( e.g., carbon tax versus cap and trade schemes; varying forms of alternative non-fossil fuel energy etc.; resort to nucclear power). But denial that global warming is, in fact, occurring and brings with it possible catastrophic consequences in species depletion, sea level rises etc. seems totally unwarranted. Why then is there so much of it ? It turns out that there are strong vested interests ( fossil fuel companies and their lobbies; anyone who is a libertarian against any increase in governmental regulations) who want to deny the scientific evidence. As Mann notes, skepticism ( something science should engage in, precisely in order to clarify data and get the facts right) is not the same as denialism.
As Mann notes: "As both the climate wars and the hockey stick battle continued, it was increasingly unclear that any amount of evidence or additional work would satisfy the critics. After all, the attacks against the hockey stick fundamentally, as we have seen, were not really about the work itself. They were part and parcel--forgive the pun-- of a proxy war against the science and its icons being fought by, or at least often funded by, powerful vested interests who found the scientific evidence for climate change inconvenient for political, financial or philosophical reasons." Of course, ignoring the scientific evidence of global warming will be more than just inconvenient for future generations. Ignoring the evidence could have catastrophic implications.
Denialists tend to make the following six points: (1) CO2 is not actually increasing. (But we can confidently measure the increase of CO2 in the atmosphere from the start of the Industrial Revolution from 280 parts per million to the present 392p.p.m.!); ( 2) Even if CO2 is increasing, the increase has no impact on the climate since there is no convincing evidence of warming ( Despite three of the years in the past decade being the warmest in centuries; despite glacier melting; despite droughts and extreme weather storms!); (3) Even if there is warming, it is due to natural causes. Mann rather carefully sifts through possible natural causes of climate shifts ( El Nino and La Nina effects, volcano activity, solar intensity). They can not explain the climate rise. In fact, they should be yielding a slight global cooling but are not! (4) Even if the warming cannot be explained by natural causes, the human impact is small and the impact of continued green house gas emisions will be minor. (Not if the sea level rises predicted occur. We are on present course to increase--if we go on the pattern we are going-- to 450ppm of CO2 by the mid twenty-first century which almost all climatologists see as a potential tipping point with quite serious ecological consequences; (5) Even if the current and projected future human effects on earth's climate are not negligible, the changes are generally going to be good for us. This reminds me of remarks friends from Cleveland, experiencing an unseasonably warm winter, made: " If this is global warming, I want more of it." Some areas ( Canada, Russia) will benefit from global warming with longer growing seasons for wheat etc. But calculations are that global warming will be a global net loss for Africa, the South West of the United States, many parts of Latin America and Australia and, overall, globally a net loss; ( 6) Whether or not the changes are going to be good for us, humans are very adept at adapting to changes; besides, it is too late to do anying about it and/or a technological fix is bound to come along when we really need it. Actually, we really need it now! Some of the projected tipping points leave little room for any easy technological fix!
What I found most interesting in Mann's book was the concerted effort by climate deniers (such as the Hearland Institute; the George Marshall Institue; foundations financed by the Koch brothers; Exxon-Mobil, The Scaife Foundation--almost all through fossil fuel money) to orchestrate media campaigns ( even harsh political near persecution of climate scientists) sowing doubt. These manufacturers of doubt ( acting much similar to those who poked fun at the evidence of health harm from tobacco had done earlier) seem to be following advice given by Frank Lutz to Republicans in 2002 that the science of global warming might undermine their programs if they did not sow systematic doubt about the scientific uncertainty of global warming.
Mann is illuminating about the so-called' climate gate' scandal' when hacked e-mails from the server of the Center for Climate Research at the University of East Anglia were made public (often in a distorting edited fashion). They came out right before the UN meeting on climate in Copenhagen. Two terms, in particular, were lifted up: 'Trick' which the climate deniers claimed meant a devious trick but from the whole content of the e-mail meant "a clever and helpful heuristic device for dealing with proxy data on temperature." A second canard had to do with a phrase, "hide the deline." Again, the deniers saw something devious in the phrase when, in point of fact, it really meant : be careful about accounting for tree ring data from higher latitutdes after 1960 because the influence of other forms of pollution might suggest, actually temperature deline. Hide or do not put too much value on data known to be faulty on other grounds.
Mann has been subjected to almost systematic probing by various Republican led congressional investigations (and one by Ken Cuccinelli, the Attorney General of Virginia) demanding time-consuming and extensive provision of e-mails, research papers etc. The plot line seems to be: pick off the leading scientists, harass them, that way others will be deterred. But the tactic has backfired and prominent scientific groups and editorials in The Washington Post and The New York Times began to compare the actions of Representative Darrel Issa and Senators Inhofe and Vitter or Cuccinelli as a kind of McCarthyism against science. As Mann argues it: "The scientific community and those seeking to communicate its message are greatly outmatched by a massive disinformation campagn funded by powerful vested interests driven by a single goal. That gloal is to thwart efforts to regulate carbon emissions-- a necessary step if we are to stabilize gas concentration below dangerous levels."
John A. Coleman, S.J.