I’d like to highlight a really useful information document put together by Dr Brett Parris, Chief Economist & Manager, Climate & Natural Resources Team, World Vision Australia. It’s entitled “Responses to Questions & Objections on Climate Change” and has been through some heavy revisions (currently on v3). He has also developed a scenario modeller (see below).
The climate sceptics FAQ is pretty comprehensive, running to 68 pages (PDF document here) and is well referenced. There is also a web-based html version here for convenient online browsing and cut-and-paste. Previous versions of this FAQ have been fine-tuned on the basis of iterative advice from a range of climate scientists and specialists in related disciplines, and so the content is both rigorous and reflective of the evidence-based scientific literature. I commend it to those who are interested in concise answers to a range of commonly asked sceptical questions on anthropogenic global warming.
The review covers 21 commonly raised arguments (click on number to goto):
1. The IPCC is a political body and its reports are scientifically unreliable
2. Science is not about consensus – Galileo was ridiculed by the authorities and the scientific establishment
3. There’s no consensus – 31,000 scientists signed a petition denying the link between greenhouse gas emissions and climate change
4. We should wait until there is more evidence before reducing greenhouse gas emissions.
5. Climate change has been happening throughout geological and human history. What is happening now is not outside the bounds of natural climatic variability.
6. Because what is happening now is within the realms of natural variability, we can’t say that humans are contributing to climate change.
7. Because what is happening now is within the realms of natural variability, it is not something to worry about. Species have always adapted.
8. It was warmer during medieval times
9. Climate models are unreliable
10. There was a consensus among climate scientists in the 1970s that we would soon be heading into another ice age
11. Global warming ended around 1998 anyway – it’s been cooling since then.
12. Our best strategy is simply to adapt to climate change.
13. CO2 exists only in very low concentrations in the atmosphere, therefore it cannot have significant effects.
14. CO2 is a weak greenhouse gas. Doubling of CO2 from its pre-industrial levels of 280 ppm to 560 ppm would only bring warming of about 1ºC.
15. CO2 is not a pollutant – it is completely natural and essential for life.
16. Any warming is the Sun’s fault.
17. Climate change is due to the effects of cosmic rays.
18. Lack of warming in the tropical troposphere (lower atmosphere) proves anthropogenic global warming is a myth.
19. Coming out of the ice ages, the changes in CO2 happened after the warming began, so CO2 doesn’t affect atmospheric temperatures.
20. Antarctica is cooling, so that proves the global climate isn’t warming.
21. Action on climate change would ruin our economies.
Brett’s paper grew out of his work at both Monash University and at World Vision, where his focus on the current impacts and future projections of climate change in developing countries. The interested reader is referred to the reference list and the ‘Useful Resources’ section at the end for more comprehensive websites and other materials and listing of sources. Constructive comments or suggestions for improvements can be sent directly to Brett.
I don’t expect this material to change the minds of trenchant denialists (who are immune to evidence and logic, however well presented). But for the vast majority of undecided people who might be curious about these issues but not willing to make a judgement until they know more, or for those honestly confused about what has been adequately explained by climate science versus what is too uncertain, this is a really useful resource. It is also a good place to send your sceptical friends and colleagues — at least as a starting point for whetting their intellectual appetite to learn more (or, as a quick answer to blog comments).
Usefully, Brett has also put together a simple web-based tool called the Climate Scenarios Model (written in Java/NetLogo), which generates likely climate impacts from a given amount of warming above pre-industrial levels. The impacts for different temperatures are taken from the IPCC (2007) report of Working Group II and the UK Stern Report. It has an easy-to-use interface, and is a really neat educational tool. Go try it out.
Let me say, well done Brett on a sterling public communication service.