Sunday, May 01, 2005


Climate "sensitivity" is the change in surface temperature expected for each additional Watt of energy that is re-radiated onto the earth's surface and lower atmosphere by slight changes in the greenhouse effect. The main cause of these changes in the greenhouse effect, of course, is the increasing levels of atmospheric carbon dioxide caused by the combustion of fossil fuels. You would think that it would be big news when Hansen-the guy who started all this mess with his incendiary 1988 congressional testimony-lowers his estimate for the sensitivity to two-thirds of the value he used back then.

Hansen's most recent figure, just published in Sciencexpress, is that the surface temperature ultimately changes 0.67?C per Watt per square meter (W/m2). In 1988 he said it was a full degree, and in 2001 he lowered it to 0.75. The lower the climate sensitivity, the less that the global temperature will rise in the future (given the same amount atmospheric carbon dioxide) and the lower the threat of catastrophic climate change.

But the greenhouse emissions are also much lower than people expected. The standard modeling technique raises the carbon dioxide concentration of the atmosphere 1% per year, but the actual rate of increase for the last three decades has been around 0.45% per year. And, despite scary news stories, there's little evidence for any sharp upward change. There was a lot of press when the 2003 concentration of atmospheric carbon dioxide rose considerably, and virtually no coverage when it was balanced out by much smaller changes in 2004. The United Nations Intergovernmental Panel on Climate Change (IPCC) assumes an average change of roughly 0.65% per year in carbon dioxide, or 41% greater than the observed, very constant rate.....

These are big changes and should be big news, but it is apparent that those who report on these matters may be far from a hand calculator. Hint to taxpayers, who fund over $4 billion per year in climate change research (at least that's what's in the proposed budget): all of these calculations are pretty much unnecessary. It is already become well established over the course of the past 35 years or so that the rate of global average temperature rise is a remarkably constant 0.17ºC. That would give right around 0.8ºC additional warming to 2050. In his new work, Hansen is really just doing what any rational scientist would do: adjusting the sensitivity for what has been observed in the real world....

In climate science, we really have only two tools: computer models and observations. And it is clear, when the two are combined, that future warming is going to be at the low end of the wild projections that have been made by the IPCC. What Hansen has done is really nothing more than this, lending more evidence to what we already pretty much know. The rate of future temperature rise will be modest, as will be the accompanying climate impacts. Some will be positive, some will be negative, but they will all be at the low end.

More here


If logic ever gets through to them

"Over the next ten years, I predict, the mainstream of the environmental movement will reverse its opinion and activism in four major areas: population growth, urbani-zation, genetically engineered organisms, and nuclear power. Reversals of this sort have occurred before. Wildfire went from universal menace in mid-20th century to honored natural force and forestry tool now, from "Only you can prevent forest fires!" to let-burn policies and prescribed fires for understory management. The structure of such reversals reveals a hidden strength in the environmental movement and explains why it is likely to keep on growing in influence from decade to decade and perhaps century to century.

The success of the environmental movement is driven by two powerful forces-romanticism and science-that are often in opposition. The romantics identify with natural systems; the scientists study natural systems. The romantics are moralistic, rebellious against the perceived dominant power, and combative against any who appear to stray from the true path. They hate to admit mistakes or change direction. The scientists are ethicalistic, rebellious against any perceived dominant paradigm, and combative against each other. For them, admitting mistakes is what science is.

There are a great many more environmental romantics than there are scientists. That's fortunate, since their inspiration means that most people in developed socie-ties see themselves as environmentalists. But it also means that scientific perceptions are always a minority view, easily ignored, suppressed, or demonized if they don't fit the consensus story line.

Take population growth. For 50 years, the demographers in charge of human population projections for the United Nations released hard numbers that substantiated environmentalists' greatest fears about indefinite exponential population increase. For a while, those projections proved fairly accurate. However, in the 1990s, the U.N. started taking a closer look at fertility patterns, and in 2002, it adopted a new theory that shocked many demographers: human population is leveling off rapidly, even precipitously, in developed countries, with the rest of the world soon to follow. Most environmentalists still haven't got the word. Worldwide, birthrates are in free fall. Around one-third of countries now have birthrates below replacement level (2.1 children per woman) and sinking. Nowhere does the downward trend show signs of leveling off. Nations already in a birth dearth crisis include Japan, Italy, Spain, Germany, and Russia-whose population is now in absolute decline and is expected to be 30 percent lower by 2050. On every part of every continent and in every culture (even Mormon), birthrates are headed down. They reach replacement level and keep on dropping. It turns out that population decrease accelerates downward just as fiercely as population increase accelerated upward, for the same reason. Any variation from the 2.1 rate compounds over time.

That's great news for environmentalists (or it will be when finally noticed), but they need to recognize what caused the turnaround. The world population growth rate actually peaked at 2 percent way back in 1968, the very year my old teacher Paul Ehrlich published The Population Bomb. The world's women didn't suddenly have fewer kids because of his book, though. They had fewer kids because they moved to town. Cities are population sinks-always have been. Although more children are an asset in the countryside, they're a liability in the city. A global tipping point in urbanization is what stopped the population explosion. As of this year, 50 percent of the world's population lives in cities, with 61 percent expected by 2030. In 1800 it was 3 percent; in 1900 it was 14 percent.

Along with rethinking cities, environmentalists will need to rethink biotechnology. One area of biotech with huge promise and some drawbacks is genetic engineering, so far violently rejected by the environmental movement. That rejection is, I think, a mistake. Why was water fluoridization rejected by the political right and "frankenfood" by the political left? The answer, I suspect, is that fluoridization came from government and genetically modified (GM) crops from corporations. If the origins had been reversed-as they could have been-the positions would be reversed, too.

Ignore the origin and look at the technology on its own terms. (This will be easier with the emergence of "open source" genetic engineering, which could work around restrictive corporate patents.) What is its net effect on the environment? GM crops are more efficient, giving higher yield on less land with less use of pesticides and herbicides. That's why the Amish, the most technology-suspicious group in America (and the best farmers), have enthusiastically adopted GM crops.

There has yet to be a public debate among environmentalists about genetic engineering. Most of the scare stories that go around (Monarch caterpillars harmed by GM pollen!) have as much substance as urban legends about toxic rat urine on Coke can lids. Solid research is seldom reported widely, partly because no news is not news. A number of leading biologists in the U.S. are also leading environmentalists. I've asked them how worried they are about genetically engineered organisms. Their answer is "Not much," because they know from their own work how robust wild ecologies are in defending against new genes, no matter how exotic. They don't say so in public because they feel that entering the GM debate would strain relations with allies and would distract from their main focus, which is to research and defend biodiversity.....

Can climate change be slowed and catastrophe avoided? They can to the degree that humanity influences climate dynamics. The primary cause of global climate change is our burning of fossil fuels for energy. So everything must be done to increase energy efficiency and decarbonize energy production. Kyoto accords, radical conservation in energy transmission and use, wind energy, solar energy, passive solar, hydroelectric energy, biomass, the whole gamut. But add them all up and it's still only a fraction of enough. Massive carbon "sequestration" (extraction) from the atmosphere, perhaps via biotech, is a widely held hope, but it's just a hope. The only technology ready to fill the gap and stop the carbon dioxide loading of the atmosphere is nuclear power.

Nuclear certainly has problems-accidents, waste storage, high construction costs, and the possible use of its fuel in weapons. It also has advantages besides the overwhelming one of being atmospherically clean. The industry is mature, with a half-century of experience and ever improved engineering behind it. Problematic early reactors like the ones at Three Mile Island and Chernobyl can be supplanted by new, smaller-scale, meltdown-proof reactors like the ones that use the pebble-bed design. Nuclear power plants are very high yield, with low-cost fuel. Finally, they offer the best avenue to a "hydrogen economy," combining high energy and high heat in one place for optimal hydrogen generation......

Within the environmental movement, scientists are the radical minority leading the way. They are already transforming the perspective on urbanization and population growth. But their radicalism and leadership will have to increase if humanity is to harness green biotech and step up to its responsibilities for the global climate. The romantics are right, after all: we are indi-visible from the earth's natural systems

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Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is to promote themselves as wiser and better than everyone else, truth regardless.

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