Friday, February 04, 2005
Strange weather - PSSST(KA) keeps head cool
Johann Hari put up a somewhat overheated (I'm on a roll! Har, har) column on impending catastrophical climate change. This after a new computer simulation suggested temperature increases of around a whopping eleven degrees celsius (as it is, the 11 degrees celsius number is the high end of a range whose low range is at a very modest 1.4 degrees celsius). Now, as a linguist by trade, I shouldn't really be commenting on issues like climate change. And I would have gladly kept my mouth shut, were it not for the fact that Greenpeace and other professional environmental lobbies want me, and everyone else, to have an opinion on climate change - preferably theirs. So I'll present my opinion.
First off, to enable the reader to form an accurate opinion about my objectivity, I should probably mention that some members of my family have owned shares in an oil company - but only a tiny number, and I think they may have sold them off by now. Furthermore, two of my uncles, my sister and my brother-in-law all happen to be bus drivers, providing me, of course, with a vested interest in the continuation of our fossil-fuel based economy. Oh, and my dissertation research on 17th century Finnish verbal syntax is funded by Exxon-Mobil.
The last sentence is a joke. But it does point me to a red herring used annoyingly often by environmentalists of the "shout-em-down" school of debate. As anyone with any basic schooling in the scientific method knows, in deliminating what is good research and what is crap, the funding sources of the individual scientist are as irrelevant as his religious or political convictions (they may become relevant once it is established that we are dealing with crap). Science consists in the transparent application of methods to a given subject - which should be repeatable and therefore controllable - in which factors like the identity of the scientist have no meaning. Only in the bizarre twilight zone of Postmodernist "Science Studies" and some such manure are political preconceptions and values irretrievably thought to colour the results of research.
So when Johann Hari claims that:
So I talked to dozens of distinguished climatologists seeking confirmation - and I have to tell you: it's not good news. They all agreed: the sceptics have no more scientific credibility than the people who insisted for decades that there was no relationship between smoking and lung cancer. There is legitimate dispute about the extent of climate change, but - as one climatologist told me off the record - "find me a scientist who denies the link between the actions of man and the changes in the climate, and I'll find you money from the oil, gas and energy companies."
He has been told something irrelevant, regardless whether it is true or not (as it probably is not).
My apologies for banging on about this - but there is a point here. There seems to me to be a strange prejudice that privately funded research - and particularly by commercial outfits from Monsanto or the tobacco companies - is crap by definition, whereas state-funded research is, of course, a selfless search for truth. I think there is no reason at all to assume such a thing. At root is a naive supposition that the private sector is only interested in misleading the public (as opposed to, say, the government, which as we all know, is always interested in the truth). To wit, they would not be particularly successful capitalists if that were true.
And as an ultimate example of the independence of funding sources and scientific results, I might mention that a fair share of Noam Chomsky's research has been funded by... the Pentagon. And it is not invalidated by that fact at all.
But I was going to give you my opinion on climate change:
1) Surface temperatures seem to have been warming over the last few decades. But even that is not the whole story: satellite records seem to indicate a far slighter warming, whereas observations from weather balloons even indicate a slight cooling.. The satellite records have been criticized on the grounds, if I recall, that slight changes in the height of their orbits caused anomalous readings. However, the surface temperature records suffer from such uncertain factors as quality of maintenance of individual weather stations and environmental changes (if the area around a weather station got urbanized during the last few decades, you will notice this in temperature records).
2) The climate has always been changing - with high temperatures around 800-1300 (the colonization of Greenland!), low temperatures during the "Little Ice Age" from 1400-1800, and a gradual rise since then. More here. During the last century, however, temperatures have been falling from about 1940 to well into the 1970s. This probably contributed to the Allies winning the Second World War: German troops went into the Soviet Union in 1941 way too lightly dressed and were confronted with an unusually cold winter. Needless to say, this does not correspond with a drop in atmospheric CO2.
These variations in climate over the past millenium have recently been ignored in a model - the so called "hockeystick" - which basically suggested a steadily cooling climate until a dramatic rise in temperatures at the end of the 20th century. Critique on this model here.
3) Atmospheric rise in CO2 is far from the only factor acting on climate change: there are many, and they typically interreact (a rise in CO2 could unleash mechanisms that strengthen temperature increase, or that dampen it). There seems to be a fascinating correlation between temperature (in this case, mean Northern Hemisphere temperature) and the length of solar cycles which does seem to fit in well with the 1940-1970 cooling and subsequent warming - but the causal mechanisms that could underly such a correlation are, as I know, not really known. More about that here and here.
4) Most of the predictions of warming are based on computer models, which are about as good as the data fed into it. In climate change, this seems to me to be a problem - as the number of variables involved is very high and some of them (remember the sunspot cycles) poorly understood.
5) I think there is no basis at all for Johann Hari's alarmism. Human influence on the climate probably precedes the industrial revolution by more than ten millenia, as Philip Stott points out:
Secondly, do humans influence climate? Again, the answer is: 'Of course they do.' Hominids and humans have been affecting climate since they first manipulated fire to alter landscapes at least 750,000 years ago, but possibly as far back as two million years. Recent research has further implicated the development of agriculture, around 10,000 years ago, as an important human factor. Humans influence climate in many ways, through altering the albedo (the reflectivity) of the surface of the Earth, through changing the energy balance of the Earth, by emitting particles and aerosols, as well as by those hoary old favourites, industrial emissions.
Here we encounter the second major difference between the science and the myth. In fact, human influences on climate are multi-factorial. Unfortunately, we know precious little about most of them. My own instinct is that our ability to change the reflectivity of the Earth's surface will, in the end, prove to have been far more important than industrial emissions. After all, if Lex Luthor covered the Tibetan High Plateau with black plastic sheeting, even Superman might have problems dealing with the monsoons.
I strongly doubt future climate change to be any more catastrophic than the past. A new ice age is probably waiting in the wings at some point in the future, though.
6) Mick Hume has a good column on the issue of consensus in science and the "all climate change deniers are in the pay of Exxon-Mobil" crap, and mentions a pretty shocking government-funded advertisement:
The most shocking advert today is the one about the apocalyptic dangers of climate change from the government-funded Carbon Trust. Unlike the other two ads it has not provoked public controversy, but to my mind its message is as crude as a Tory pig or an amphibian flasher.
The Carbon Trust advert on television begins with an actor playing Robert Oppenheimer, “father of the A-bomb”. The portentous voiceover tells us: “One man has been where we all are today. When he saw what he had done, he said, ‘I am become the destroyer of worlds’ (cue shot of atomic explosion). Now we all have to face up to what we’ve done. Our climate is changing . . . ”
Patronizing and despicable. It's not important, but it's even misquoted. Oppenheimer, in fact, quoted a passage from the Bhagavad Gita: I am death, the destroyer of worlds. He wasn't saying that he (Oppenheimer) was Death, but that a personified atom bomb was death.
7) Finally, here I found a quote that Johann Hari should perhaps take to heart:
"Journalists often confuse science with philosophy," says Steve Ross, a professor at Columbia's Graduate School of Journalism. "Whether you believe global warming is happening now or is centuries away has less to do with science--we don't really know--than our own personal philosophy regarding political and environmental issues," he explains.