Some ramblings about the climate change debate

Reading up for my previous post about the Amazon rainforest and climate change, I was again reminded of the fact that the global climate change debate seems to evolve into a battle with two fronts. Let there be no doubt about it: global climate change is a fact. A vast majority of scientists - people who are trained to disagree, you could say ;-) have arrived at the conclusion that there is substantial evidence for dramatic changes going on in our climate. So why would there be a two-fronted battle?

Of course, on the one side you have your nay-sayers, sceptics and those who would rather believe in global conspiracies than in scientifically documented reports. These people will always be present in some number and typically also with some sort of agenda. Apart from the "conspiracy theorists", these people would say "it is only natural" or "there have always been ups and downs, nothing to worry". The more interesting fraction will claim that there is some degree of change in our environment, but that it is due to some hitherto unknown phenomenon, or due to some factors which have been downplayed so far.

Depending on the level of their conviction, on their underlying motivation and their agenda, it will be hard if not impossible to argue with some of these nay-sayers and come to some consensus. As in every argument where the stakes are high, you have to expect that you simply cannot reach a consensus with some part of your opposition.

So what about the other front of the battle? That is the truly surprising and truly frustrating element of the ongoing debate, as I see it: everybody and their dog seem to have become "global climate experts", and they appear with bold statements in the media and in the public debate. Unfortunately, many of these self-proclaimed or media-acclaimed "experts" and "scientific writers" and "environmental activists" do not have more than the most basic training in natural sciences, let alone ecology, geophysics or climatology.

It does not take long to select a few examples:

• the "polar ice cap" - so many statements about the status of the "polar ice" do not bother to discriminate between sea ice and glacial ice. Melting sea ice is linked with rising sea levels (hello, Archimedes!), retreating glaciers are linked to retreating pack ice distribution, the link between the "global conveyor belt" i.e. the oceans' deep-water circulation, and sea ice formation and distribution is strangely under-represented. Surprisingly many people do not even mention the fundamental differences between the "Arctic ice cap" - an ice-covered ocean - and the "Antarctic ice cap" - an ice-covered continent. Nor do they realize that even Arctic and Antarctic sea ice are affected by very different dynamics, and the "ice shelves" are by many believed to consist of sea ice, simply because shelf ice floats on the sea.

• "save the rainforest" - true, rainforests perform vital tasks in filtering water, releasing oxygen, and storing carbon. In fact, all forests on Earth perform these services to some degree. But tropical rainforests are not such great "carbon sinks" as many claim: they do not store any more carbon than is contained in their biomass, and they deposit almost nothing. That is the great tragedy of tropical deforestation: the soil that is converted into agricultural use is often so poor that it does not even serve as proper pasture. The one point where tropical rainforests do excel above temperate forests (which are much more important as carbon sinks, in that they deposit much more in their soil) is biological diversity. And unfortunately, the preservation of biological diversity is still regarded as a luxury rather than as a necessity.

• "glaciers as climate change thermometers" - how many examples of collapsing glacier fronts have been in the press, on Greenpeace campaigns, or on television programs? Common for all of them is a profound misunderstanding of glaciers acting as thermometers. True, glaciers are affected by air temperature, and they are also retreating in many locations all over the world. But to claim that air temperature alone is the driving factor of glacier extent is ignoring all the other factors that together make up the specific mass balance and dynamics of a glacier, like size, precipitation received, altitude, proximity to the sea, underlying bedrock etc. pp.

Also, in many cases reports claim that the status "before" the onset of climate change was "natural", while the current status "after" climate change is not. But where is the original extent, the reference line against which we should compare current levels? And how would such a reference be meaningful?

There are a number of other examples where some "experts" among the "supporters" as well as the "sceptics" are mixing up facts, misunderstanding or misinterpreting them. And this is the truly puzzling part of this: if somebody without proper medical training makes a bold diagnosis on a patient, very few people would be inclined to take this very seriously. But in ecology, geophysics, or oceanography, there seems to be a much lower threshold. Why?

So this is where I see the second "front" in the "battle" over climate change: the so-called "experts" (of both parties) who got it wrong. In between these two fronts, between the sceptics and the unqualified "experts" are the scientists and campaigners who actually know what they are talking about. The doctors who actually know how to diagnose a patient, if you like.

To stick with this metaphor, these doctors now have to deal with some opponents who claim that the patient is not sick at all (or that the patient is going to be all right, not to worry) while some other "doctors" enter the scene stating false diagnoses with great conviction.

Unfortunately, many of the unqualified "experts" are found among the supporters of climate change and in the conservation movement. Not only will many of these well-meaning but ill-informed "experts" react with hostility when challenged by scientists, they also play in the hands of the sceptics in a formidable way.

The great tragedy of this debate is that the ones to blame for all this confusion and especially for the existence of "experts" who got it wrong, are the scientists themselves. If the natural science education in the schools as well as the public outreach and communication of science to the public had been more thorough and more serious, I doubt that we would have this problem. Scientists will have to become and train better teachers, and they will have to become and train better science communicators.