I'm not a climate scientist per se, but I am a senior Australian scientist (biologist) with interests and expertise in environmental science. Reading Miranda Devine's piece ( ''Bring it on, Labor, pull that trigger'', August 15-16), it occurred to me that in the climate change debate there are serious misconceptions about the way science actually works. So let's shift the context from climate change to medicine.
Your health declines. You see 10 specialists and nine tell you that you have a serious, complex medical condition that requires surgery.
The 10th says you are fine and there is no need to do anything. You follow the advice of the 10th and do nothing for a year. Your health does not improve. You go back to see the specialists, and nine tell you that the condition is worse and you need the surgery urgently. The 10th still says you don't need to do anything and in fact argues that the condition is not real. What would you do?
This is exactly the state of play in climate science. The vast majority of specialists in the field say we have a major problem, that it is caused by humans, and it is probably getting worse. This is not the same as ''proof''. It is difficult if not impossible to ''prove'' complex environmental (or many other) scientific theories. Climate change science is not a high school geometry problem.
Instead what happens is that evidence is gathered that supports a theory, alternative explanations are considered and discounted on the evidence, and a consensus view emerges. As a consequence of this process the overall consensus on human-induced climate change is now quite strong among experts in the field. Thus comments by Senator Fielding or others of like mind who deny climate change, or the need for us to act, on the basis that ''the science is unproven'' or ''science does not work by consensus'' are misleading. They do not reflect how most science actually works.
I suspect my comments may actually be used to argue against the reality of climate change (''Senior scientist says climate change not proven!''). In response I go back to my parable. Your health or even your life is on the line and nine of 10 specialists propose a diagnosis and subsequent course of action. What would you do?
Professor Peter Steinberg Mosman