Welcome to Axe's Corner.  This year's special is on climate change, the science behind it, and why Senator Fielding is a terribly misinformed and misleading individual.

 

I've tried to put some convincing information on this page (or linked to this page). However, if you read this and are still not convinced, drop over to the forums and raise your objection, and we'll resolve that as well :).

 

We'll start with the reports from the UN Intergovernmental Panel on Climate Change (IPCC), an intergovernmental scientific body. The IPCC released a 2007 report which found that 11 of the last 12 years were rank among the 12 warmest years in the instrumental record of global surface temperature (a point that directly contradicts a statement made by Senator Fielding on SBS news on 23 June 2009). The report goes on to present a range of evidence which clearly indicate a rise in global surface temperatures and sea level, and a fall in northern hemisphere snow cover, particularly since the 1950s.

 

The report then looks into the causes of climate change, examining closely the role of human industrial activity. The report notes that atmospheric concentrations of Greenhouse Gases (GHGs, which include Carbon Dioxide, Methane, Nitrous Oxide, Hydrofluorocarbons, Perfluorocarbons and Sulphurhexafluoride) have increased by 70 per cent between 1970 and 2004. Further, levels of Carbon Dioxide, Methane and Nitrous Oxide have increased markedly as a result of human activity since around 1750, and now exceed pre-industrial values of these chemicals (taken from ice core samples spanning many thousands of years).

 

• Carbon Dioxide and Methane levels in 2005 far exceeded the natural range for these gases recorded over the last 650,000 years. The report goes on to note that Carbon Dioxide concentrations are due primarily to fossil-fuel use by humans, and that it is very likely that the increase in Methane is due to agricultural activity and fossil fuel use. The high Nitrous Oxide levels are due primarily to agricultural activity. In all three cases, the high concentrations are driven almost entirely by human activity. The chart, below (not from the report) shows estimated Carbon Dioxide levels in parts per million over the last 400,000 years - clearly, the current levels are unprecedented are far above other natural cyclical peaks shown on the chart.

 

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• The report notes that the observed increase in global average temperatures since 1950 is very likely due to the increase in GHGs because of human activity.

 

• It also notes that it is very likely that this warming has contributed to sea level rise since the 1950s.

 

The next point the report makes is that continued GHG emissions at or above current rates would cause further warming and induce many changes in the global climate system during the 21st century that would very likely be larger than those observed during the 20th century.

 

Some of the concerns raised by the report is that as the temperature warms, due to increased GHGs, the capacity of the ocean to absorb carbon dioxide diminishes, creating a feedback loop whereby for a given rate of emission, the concentration of Carbon Dioxide rises at an ever-increasing rate, nothing that the strength of this feedback loop is still not clear.

 

In regard to dealing with the issue, the report points out that both bottom-up and top-down studies indicate that there is high agreement and much evidence of substantial economic potential for the mitigation of global GHG emissions over the coming decades that could offset the projected growth of global emissions or reduce emissions below current levels. Mitigation is important, because many impacts of climate change can be reduced, delayed or avoided by mitigation. Mitigation efforts and investments over the next two to three decades will have a large impact on opportunities to achieve lower stabilisation levels (peak global temperature). Delayed emission reductions significantly constrain the opportunities to achieve lower stabilisation levels and increase the risk of more severe climate change impacts.

 

If you're not keen on the IPCC as a group of Scientists, then there's always the Royal Society, one of the world's oldest and most respected scientific bodies. They have on their site a handy "A guide to facts and fictions about climate change" (endorsed through peer-review and by the Council of the Royal Society). I highly recommend it as reading for anyone not yet convinced about climate change, but if you're not up to it, here's a handy summary of their points:

 

Misleading Argument 1: The IPCC has become too politicised and does not accurately reflect the wide range of views within the scientific community. The IPCC summary for policymakers does not adequately represent the scientific uncertainty.

Rebuttal: Statements of support for the IPCCs work have been provided by the science academies of Australia, Belgium, Brazil, Canada, the Caribbean, China, France, Germany, India, Indonesia, Ireland, Italy, Malaysia, New Zealand, Sweden and the UK. Further, the US National Academy of Sciences stated that “The IPCC’s conclusion that most of the observed warming of the last 50 years is likely to have been due to the increase in greenhouse gas concentrations accurately reflects the current thinking of the scientific community on this issue.”

 

Misleading arguments 2. Many scientists do not think that climate change is a problem. Some scientists have signed petitions stating that climate change is not a problem.

Rebuttal: In the journal Science in 2004, Oreskes published the results of a survey of 928 papers on climate change published in peer-reviewed journals between 1993 and 2003. She found that three-quarters of the papers either explicitly or implicitly accepted the view expressed in the IPCC 2001 report that human activities have had a major impact on climate change in the last 50 years, and none rejected it. Generally, "scientific reports" discrediting climate change are actually political lobbying funded by vested interest groups (such as oil producers).

 

Misleading arguments 3. There is little evidence that global warming is happening or, if it is happening, it is not very much. Some parts of the world are actually becoming cooler. Increased urbanisation could be responsible for much of the increase in observed temperatures. Satellite temperature records do not show any global warming. If there has been global warming recently, it would not even be a unique occurrence within the past 1000 years. Europe has been much warmer in the past.

Rebuttal: Few scientists dispute that the global average temperature has been rising for at least a century. The IPCC 2001 report concluded, based on worldwide measurements, that the average surface temperature of the Earth had risen by 0.6 centigrade degrees (+/-0.2°C) during the 20th century. The IPCC found that, in terms of the global average temperature, the 1990s were very likely (a 90-99% chance) to have been the warmest decade since records began in 1861, and that 1998 was the warmest year.

Furthermore, the increase in surface temperature during the 20th century in the Northern Hemisphere was likely (a chance of 66 to 90%) to have been greater than for any other century for the last 1000 years.

 

Misleading arguments 4. The Earth is getting hotter, but not because of emissions of greenhouse gases from human activities. Carbon dioxide makes up such a tiny fraction of the atmosphere that even if it doubled it would make little difference to the climate. Variations in the sun are more likely to be the cause of climate changing than increases in greenhouse gases.

The IPCC found that the dominant influences on climate change in the early part of the 20th century were likely to be a small increase in solar output and a decrease in average volcanic activity. However, such natural factors cannot explain the warming in the latter half of the 20th century, and the IPCC concluded that there is “new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities”. The report pointed out that natural factors on their own would have produced an overall drop in global average temperatures.

 

OK - if you've got this far, the responses in the document are getting a bit large to summarise. Take a look at the misleading arguments - if you believe these arguments, then fire up the Royal Society's Guide and read the appropriate response.

Misleading arguments 5. There is no reliable way of predicting how temperatures will change in the future. The climate is so complex that it is hard to predict what might happen. The IPCC’s climate scenarios are developed by economists not scientists and are often misleadingly presented as predictions or forecasts, when they are actually just scenarios – the most extreme of which are totally unrealistic The IPCC’s findings are dependent on models that are badly flawed. No climate model has been scientifically validated. The IPCC 2001 predictions showed a wider uncertainty range than that in earlier reports.

 

Misleading arguments 6. Scientists have been exaggerating the evidence by claiming that individual extreme weather events have been caused by climate change. The recent flooding in the UK in places like Boscastle and Carlisle would have happened anyway, and the frequency of hurricanes hitting the Caribbean and Atlantic coast of the United States is no different than in the past. Even if they appear to be more severe, this is only because more people are living in places that are affected by natural extreme weather events.

 

Misleading arguments 7. There is conflicting evidence about whether the ice at the poles is melting and, in fact, it is actually becoming thicker in Antarctica.

 

Misleading arguments 8. There is little evidence of a rise in sea level due to global warming. There is no correlation between rises in climate temperature and sea levels. There has been no consistent trend this century, with sea level rising in some places but not in others. Even if sea level is rising it has nothing to do with global warming and is actually due to the fact that southern England is sinking due to the bending of the Earth’s crust.

 

Misleading arguments 9. Even if climate change is occurring, it won’t be that dangerous. Abrupt climate change is just another scare story. While an atmospheric concentration for carbon dioxide of 550 parts per million has been proposed as a political target, there has been no scientific determination of “dangerous” levels of greenhouse gas concentrations.

 

Misleading arguments 10. There is no evidence that climate change will be bad for people. In fact, warmer weather will actually be good for those people who live in cold countries. Climate change may make some places like Russia warmer and more productive places to live. A warmer climate will be good for the UK’s economy, with more tourists and better wine-producing conditions. Increasing levels of carbon dioxide would produce a rise in plant productivity and crop yields. Surely we should let the benefits and costs of climate change even themselves out.

 

Misleading arguments 11. There are too many uncertainties about climate change and its impacts to justify taking action. It would be better to wait until we are more certain about climate change before acting.

 

Misleading arguments 12: The Kyoto Protocol is a waste of time because the United States will not ratify it. The emission reduction targets required under the Kyoto Protocol are“trivial” and would do no more than postpone global warming by six years. Implementing the Kyoto Protocol would be too costly. The trillions of dollars that would be wasted on the Kyoto Protocol should be spent on helping developing countries tackle poverty.

 

So, there ya go. Stay tuned for a link to a place to discuss these issues, very shortly.....