Post by Mech on Jul 17, 2007 6:54:17 GMT -5
The truth is, we can't ignore the sun
London Telegraph | July 16, 2007
David Whitehouse
According to the headlines last week, the sun is not to blame for recent global warming: mankind and fossil fuels are. So Al Gore is correct when he said, "the scientific data is in. There is no more debate."
Of that the evangelical BBC had no doubt. There was an air of triumphalism in its coverage of the report by the Royal Society.
It was perhaps a reaction to the BBC Trust's recent criticism of the Corporation's bias when reporting climate change: but sadly, it only proved the point made by the Trust.
The BBC was enthusiastically one-sided, sloppy and confused on its website, using concepts such as the sun's power, output and magnetic field incorrectly and interchangeably, as well as not including any criticism of the research.
But there is a deeper and more worrying issue. Last week's research is a simple piece of science and fundamentally flawed. Nobody looked beyond the hype; if they had, they would have reached a different conclusion.
The report argues that while the sun had a significant effect on climate during most of the 20th century, its influence is currently dwarfed by human effects. It says that all known solar influences since about 1990 are downward and because global temperature has increased since then, the sun is not responsible.
No. The research could prove the contrary. Using the global temperature data endorsed by the Inter-national Panel on Climate Change, one can reach a completely different conclusion.
Recently the United States' National Oceanographic and Atmospheric Administration said that 2006 was statistically indistinguishable from previous years.
Looking at annual global temperatures, it is apparent that the last decade shows no warming trend and recent successive annual global temperatures are well within each year's measurement errors. Statistically the world's temperature is flat.
The world certainly warmed between 1975 and 1998, but in the past 10 years it has not been increasing at the rate it did. No scientist could honestly look at global temperatures over the past decade and see a rising curve.
It is undisputed that the sun of the later part of the 20th century was behaving differently from that of the beginning. Its sunspot cycle is stronger and shorter and, technically speaking, its magnetic field leakage is weaker and its cosmic ray shielding effect stronger.
So we see that when the sun's activity was rising, the world warmed. When it peaked in activity in the late 1980s, within a few years global warming stalled. A coincid-ence, certainly: a connection, possibly.
My own view on the theory that greenhouse gases are driving climate change is that it is a good working hypothesis - but, because I have studied the sun, I am not completely convinced.
The sun is by far the single most powerful driving force on our climate, and the fact is we do not understand how it affects us as much as some think we do.
So look on the BBC and Al Gore with scepticism. A scientist's first allegiance should not be to computer models or political spin but to the data: that shows the science is not settled.