Good News for Nobel Laureates

Bob Foster

Remember the statement released on 7 December last in Oslo, at the centenary celebrations for the Nobel Peace Prize? It was edited by John C. Polyani of Canada (1986 Chemistry Prize), although it sounds rather like what the Swedish Royal Academy of Science has been saying recently. The 108 signatory Nobel Laureates (30 didn't sign) tell us that:

Never mind that over the last 20 years and more, almost all warming has been north of 30 ºN, with little or none in 'equatorial climates' or in the Southern Hemisphere. Never mind that Osama (long may he live in peace) was not 'poor'; although, as the seventeenth of 52 siblings, he may well have suffered from a lack of paternal quality-time when young. However, you can see why the Laureates are worried. When the UN's Intergovernmental Panel on Climate Change released its Third Assessment Report in 2000, the most-publicized conclusions were: an average global surface temperature increase of up to 5.8 degrees Celsius between 1990 and 2100, and (because warm water expands) resultant sea level rise up to 88 centimetres. Frightening!

Greenhouse warming is a phenomenon of the atmosphere. Human-caused emissions (for example, carbon dioxide from coal-fired power stations) supplement the dominant greenhouse gas, naturally-occurring water vapour, in the atmosphere---and thus intercept a little more of the heat leaving Earth. The lower atmosphere is supposed to warm as a result; and some of this extra warmth should then be redistributed back to the surface, rather than onward to Space. We call this consequent surface warming the 'greenhouse effect'.

But from 1979 we have satellite records; and the lower atmosphere has warmed only a third as fast as the surface. The simplest explanation is that for this 23 years, at least, most surface warming is not 'greenhouse effect' warming! Human-caused greenhouse warming appears confined to places like Alaska/Yukon, and particularly Siberia, under the very cold (and bone dry) high-pressure cells of winter. The result is a slightly longer growing-season---and stronger growth, too, because of a CO2-enriched atmosphere (think commercial greenhouses).

In Europe, the latest manifestations of a long-running ca 1500-year warm/cold cycle are the Roman Empire Warm Period, Dark Ages, Mediaeval Warm Period, and Little Ice Age. The last cold snap of the Little Ice Age was AD1800-20, with a warming trend since. Warmth is better.

Overprinted on this trend are marked warming from the 1920s, slight cooling from the 1940s, and renewed warming from the 1970s. In fact, the Great Pacific Climate Shift of 1976/77, with its sharp reduction in the upwelling of cold water in the NE Pacific, was the climatic event of the twentieth century. This remarkable warming step was followed by physical and biological changes far beyond the Pacific. The modest 0.6 ºC warming since measurements began in 1860 mostly looks like rebound from the Little Ice Age---overlain by shorter-term cyclicity. What drives these natural cycles? We don't really know; but I'll bet it's the Sun.

The UN's World Summit on Sustainable Development in Johannesburg discussed at length how to stabilize global climate. And in Mozambique on 1 September, PM Tony Blair said in support 'we can defeat climate change if we want to'. But all such efforts must fail; because, inevitably, climate will continue to fluctuate on many time-scales. Let me repeat: we can't stabilize climate. The same applies to extreme weather events: of course they will keep coming. Prevention is not on; and mitigation is the only plausible answer.

Vain attempts to stabilize climate by restricting emission of greenhouse gases will hurt us all economically, and the poor will suffer most. Instead of tilting at greenhouse windmills, the Summit might better follow the 'Skeptical Environmentalist' Bjørn Lomborg (New York Times, August 26). He wants it to concentrate on ways to 'provide every person in the world with access to basic health, education, family planning, and water and sanitation services'.

But, 0.6 ºC in the past is not the problem, surely---it is 5.8 ºC in the future. I bring good news. Ian Castles, Australian National University Visiting Fellow and former Australian Statistician, has teased-out the economic assumptions underpinning that menacing projection, and finds them extremely implausible.

IPCC invokes a worst-case 'storyline' incorporating a whole-world per-capita growth in goods and services of an unimaginable 35 times between 1990 and 2100---goodbye poverty, everyone will be rich! It then builds a scenario in which that growth is largely powered by coal; and, after calculating how much carbon dioxide might end up in the atmosphere as a consequence, applies the most sensitive of 7 numerical climate models to achieve its 5.8 ºC. This is just quantified arm-waving. For instance, the high-end scenario has world coal consumption growing 31% in 1990--2000. Actually, it fell slightly.

But IPPC gives a range for 2100, with its lowest-emission scenario yielding a rise of 1.4 ºC. The 'right' answer still could be bad, couldn't it? I have more good news. Ian Castles finds that the low-end projection is also extremely implausible. Here, although growth in the OECD is assumed to be modest, per-capita real-terms GDP grows 70 times in Asia (excluding Japan) in 1990--2100. Even for the rest of the developing world (Latin America, Africa and Middle East) it is nearly 30 times---and yet in 2002, this train is still at the station. The mother of all economic miracles gives context: Japan's twentieth century growth was below 20 times.

Come clean, IPCC! Tell people in Oslo and Johannesburg that neither end of the range you give for AD2100 has any plausible basis. Instead, concentrate on the here-and-now. For instance, 100 million people already live within 1 metre of mean sea level. Also, the UN's Arab Human Development Report 2002 tells us that in the 22 countries studied, half the women still can't read and write; and population is expected to increase from 280 to over 410 million by 2020. Finally, destruction of natural habitat continues apace, including in our own Queensland. With problems like these for Laureates to address, greenhouse will never be missed.