By Roskam, John
Review - Institute of Public Affairs , Vol. 62, No. 4
Turning up the heat on climate change alarmists John Roskam reviews: Climate: The Counter Consensus By Prof. Bob Carter (Stacey International, 2010, 200 pages)
In February this year, Penny Wong, the then climate change minister said: ?Globally, 14 of the 15 warmest years on record occurred between 1995 and 2009' and she argued that the Bureau of Meteorology had concluded that ?2009 was the second hottest year in Australia on record and ended our hottest decade. In Australia, each decade since the 1940s has been warmer than the last.'
It is claims such as these that provide the justification for Australia putting a ?price on carbon' to reduce our emissions of carbon dioxide. However, as Professor Bob Carter explains, what Penny Wong said might be true, but in the debate about climate change the minister's claims are meaningless. As Carter says ?Minister Wong's statement, and others like it, are scientifically trivial and appear to be deliberately intended to mislead. In reality it is no more significant that 14 of the last 15 years are the warmest since instrumental records began than it is that the hottest days of each year cluster around and shortly after midsummer's day.'
That's because we only have about 150 years of accurate, instrument-measured, temperature records. In the context of the history of the earth's climate what's occurred in the last few decades is not unusual. In the nineteenth and twentieth centuries temperatures increased following the ?Little Ice Age', successive phases of which lasted from roughly 1350 to 1860. The Little Ice Age followed the ?Mediaeval Warm Period' of 800 to 1000 AD. Reconstructed temperatures for the Mediaeval Warm Period are based upon proxy data such as tree ring analysis and various geochemical measurements, which imply that at many localities temperatures then were as warm or warmer than those of today. Similarly, during the ?Holocene climatic optimum' of several thousand years ago, temperatures were a degree or so warmer than they are now; during the last interglacial period 125,000 years ago temperatures were approximately two degrees warmer than now; and six million years ago, temperatures were about two to three degrees warmer than now.
None of this was mentioned by Penny Wong. Nor did she mention that it is likely that global temperatures peaked in 1998 and started declining in 2002. The new minister for climate change, Greg Combet, hasn't taken the trouble to talk about any of this either.
As we find out from Climate: The Counter Consensus there's lots of other things we haven't been told by those politicians who believe that humans are causing potentially catastrophic global warming and that therefore drastic action must be taken.
While the politicians are constantly telling the public ?the science is settled' and there's a ?consensus', they have never dared inform the public of the basic facts of climate change. Thankfully it's an omission rectified by Professor Carter.
Carbon dioxide, water vapour, methane, nitrous oxides, and ozone are called ?greenhouse' gases because they absorb heat and warm the atmosphere. Without greenhouse gases the temperature of the earth's atmosphere would be about minus 19°C. The proportionate impact of each of the greenhouse gases on atmospheric warming is approximately as follows: 78 per cent from water vapour, 20 per cent from carbon dioxide, and 2 per cent from the other gases. Of the carbon dioxide in the atmosphere, up to 5 per cent is the result of burning fossil fuels. What this translates into is that 0.45 per cent of the greenhouse warming in a particular year is the result of human activity. Or expressed in another way, 99.55 per cent of the greenhouse effect has nothing to do with carbon dioxide emissions caused by humans. It's widely acknowledged that partly as a result of human activity atmospheric carbon dioxide levels have increased, but as Carter points out the impact of this increase is disputed. …