In October last year, on the eve of Russia's ratification of the Kyoto Protocol, Greenpeace climate campaigner Steve Sawyer proposed a toast to the Russian Parliament. Kyoto was about to become a reality. The end of a hard-fought, eight-year campaign was near.
Greenpeace campaigners may celebrate again today (February 16, 2005), as the agreement becomes legally binding. Industrialised countries that have ratified the Protocol will be required to reduce their emission of greenhouse gases by an average of 5.2 per cent during the first implementation period -- between 2008 and 2012.
It is my assessment that global temperatures will start to cool some time soon -- but for mostly unrelated reasons. Indeed there has never been a period in the earth's long history when climate was constant.
Let me explain. The Kyoto Protocol is intended to reduce what has been a dramatic increase in carbon dioxide levels since the 1960s. Interestingly, however, while carbon dioxide levels have been rising the expected corresponding dramatic increase in global temperatures has not occurred. Temperatures have increased on average by only 0.6°C since the late 19th Century. The all-Australian mean temperature for 2004 was only 0.45°C above the Bureau of Meteorology (BOM) long term average.
It has been wrong to assume that temperatures would dramatically increase because carbon dioxide levels were rising. The historical correlation between atmospheric carbon dioxide levels and temperature is not particularly good.
Most of the recent global increase in carbon dioxide levels has occurred since the 1960s. Temperatures have increased over this period but also jump around from year to year. During 1974, for example, it was on average nearly a degree colder than the Bureau of Meteorology long term average. 1976 and 1984 were also cold years. Temperatures were increasing during the early 1900s when carbon dioxide levels were much lower. Temperature then started to fall in the 1940s while carbon dioxide levels continued to rise.
Volcanic eruptions and sun spot activity correlate more closely with changes in the earth's temperature, than do carbon dioxide levels. Furthermore, ice core data indicate that dramatic changes in temperature generally precede, rather than follow, changes in atmospheric carbon dioxide levels.
Temperatures increase during interglacial warm periods and then typically drop dramatically with the onset of an ice age. Trends in the long term geological record -- ice and sediment core data from the last 400,000 years -- suggest we may be nearing the end of the current interglacial warm period which has lasted about 10,000 years. This is about as long as interglacial warm periods tend to last.
It is a misconception to believe that stabilising carbon dioxide levels will stabilise temperature. The extent of the climate change misinformation should be of concern, particularly to climate scientists who know that public perception about climate does not correlate well with reality. But few scientists speak out.
Indeed many scientists play up the concept of human-induced climate change on the basis it can't be bad for the environment or their research funding. Climate change research has become an industry -- worth billions of dollars -- with the public being continually told how bad it could be based on "what if" scenario models. The recent On Line Opinion article by Greenpeace made much of them. These "what if" models, however, are not forecasts.
Hurricane expert Dr Chris Landsea recently resigned from the United Nations Intergovernmental Panel on Climate Change (IPCC) because those managing the information were not respecting the evidence. In particular public announcements were being made by a research leader suggesting that there had been an increase in extreme weather events, when the evidence showed quite the contrary.
There is often reference to an increase in insurance claims as a consequence of more hurricanes in the US. Yet both the number and intensity of hurricanes, as measured by the National Weather Service Tropical Predictor Center in Florida, show a reduction not an increase since the 1940s. For example, during the 1940s and 1950s, 23 and 18 hurricanes (respectively) hit the US with 8 and 9 of these hurricanes (respectively) classified as severe. During the 1980s and 1990s 16 and 14 hurricanes (respectively) hit the US with 6 and 5 of these hurricanes (respectively) classified as severe.
Interestingly there has also been a slight decrease in the number of cyclones occurring in the Australian region.
The increase in insurance claims is real, but actually attributable to a dramatic increase in the number of people living by the sea and building more expensive homes in these more hurricane and cyclone prone areas, rather than an increase in the number or severity of extreme weather events.
I am not suggesting that we shouldn't do something about the real increase in carbon dioxide emissions from the burning of fossil fuels. But I also think something should be done about the extent of the misinformation, much of it spread in the name of doing the right thing by the environment. We may live in the information age and all be concerned about the environment and climate change, but our level of concern is only exceeded by our ignorance of the dynamic nature of climate.
So Kyoto is now legally binding, and we may at last be able to see a reduction in global carbon dioxide emission. But this will not stop climate change. As surely as night follows day, and winter follows autumn, there will be another ice age.
Our governments would do well to put some time and resources aside to think and plan for this. A dramatic drop in temperature will be felt a lot harder by the world's fauna and flora than the average 0.6°C global temperature increase that has occurred over the last 150 years. Here perhaps is a new campaign for Greenpeace -- how to protect biodiversity from the next ice-age?
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