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Handy or erect ?

December 18th, 2003

Talking of the Scientific American, the November issue has a very interesting article on the discovery of some early human fossils in (the former Soviet Republic of) Georgia, generally assigned to Homo erectus but having a lot of characteristics in common with the earlier Homo habilis. One scientist quoted in the story even uses the phrase “missing link”.

This should be a big problem for scientific creationists, who generally argue that fossils classified as Homo erectus are just Homo sapiens and that Homo habilis is an extinct ape.

But, as we’ve seen from the debate over global warming, it’s unlikely that the accumulation of evidence will change the minds of those whose commitment to a particular viewpoint wasn’t based on empirical evidence in the first place.

Update Bargarz has more.

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  1. Grant
    December 30th, 2003 at 03:56 | #1

    Ken,

    Quite right that you should be cynical, I should have written ‘the rate of growth has fallen’ and referenced to all GHG’s rather than just CO2. I do appreciate that this is somewhat different to ‘fallen’ although the accompanying graph does appear to imply a fall in the forcing effects.

    http://www.giss.nasa.gov/research/stories/20020114/

    A few quotes:-

    “The decrease is due in large part to cooperative international actions of the Montreal Protocol for the phase-out of ozone depleting gases,” said Dr. James Hansen of NASA’s Goddard Institute for Space Studies, New York. “But it is also due in part to slower growth of methane and carbon dioxide, for reasons that aren’t well understood and need more study.”

    “Another warming agent deserving special attention, according to the authors, is soot. Soot is a product of incomplete combustion. Diesel powered trucks and buses are primary sources of airborne soot in the United States. Even larger amounts of soot occur in developing countries. ”

    Note the last paragraph particularly. This is what happens when the developed countries export their older (and therfore more affordable) technologies to all the developing nations that ask for them. Export of the hardware is closely followed by export of the production work that the older technologies were originally used for. Which products are then imported by the developed countries since they offer a ‘cheapest supplier’ source. Such policies may be useful for re-distributing wealth but do little for global ecological issues as far as I can estimate. Still, they allow claims of emission reductions and allow a financial return on obsolete machinery.

    “Currently, technologies are within reach to reduce other global air pollutants, like methane, in ways that are cheaper and faster than reducing CO2. ”

    That is a statement that I can relate to and makes the point much better than I did (as should be expected).

    “….Over the next few decades, Hansen said, it is important to limit emissions of forcing agents other than CO2, to buy time until CO2 emissions can be better managed.”

    And it would also allow time to do the research with better measurements, more effective models and a greater knowledge of the benefit to debenefit balance available from enhanced levels of CO2.

    Logically we should consider what will happen when (perhaps if?) the supply of fossil based fuels does indeed decrease to the point of unusability for any practical purpose. The focus would automatically turn to whatever alternatives seemed possible with the technologies available at the time. Presumably these technologies would also be assessed for negative environmental impacts. If the fossil fuel supplies do indeed expire by around 2050 I can’t see that there would be much of a problem by 2100.

    “In a new study, James Hansen of NASA’s Goddard Institute for Space Studies and Makiko Sato of Columbia University found that the growth rate of climate forcings have slowed substantially from almost 5 Watts per square meter (W/m2) per century to about 3 W/m2 since their peak in 1980.”

    So, in effect, Hansen seems to be saying that there are many factors involved, some more immediately addressable than others;

    that the predicted temperature increase is at the lower end of the published figures but he feels the even so the effect might be worse than others have predicted for that level;

    that there is still a lot to understand.

    That’s fine by me. And this was his position 2 years ago.

    Not Hansen, but still GISS, this report adds to the debate.

    http://www.giss.nasa.gov/research/stories/20030320/

    “Since the late 1970s, the amount of solar radiation the sun emits, during times of quiet sunspot activity, has increased by nearly .05 percent per decade, according to a NASA funded study.

    “This trend is important because, if sustained over many decades, it could cause significant climate change,” said Richard Willson, a researcher affiliated with NASA’s Goddard Institute for Space Studies and Columbia University’s Earth Institute, New York.”

    Hansen has something on Ocean warming here;

    http://www.giss.nasa.gov/research/stories/20030903/

    and some more on soot here;

    http://www.giss.nasa.gov/research/stories/20031222/

    “The calculated global warming from soot in snow and ice, by itself in an 1880-2000 simulation, accounted for 25 percent of observed global warming. ”

    Here’s a thought.

    These days a lot of soot comes from diesel fuel usage. However diesel is considered better than petrol in ecological terms from an emissions perspective. People opposed to diesel were worried about the effect of particulates on health. So new diesel fuels with smaller particulates have been developed out of legal necessity. These have a less clogging effect on the lungs and so on. Very much less. The particlates are now small enough to pass through the membranes and enter the blood stream.

    Good move! Unintended consequences I suppose.

    However I assume that the volume of soot particle output is much the same, just more difficult to see. So presumably the affect on planet albedo is also about the same – or might it be worse by spreading further and more consistently?

    Grant

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