Wednesday, May 16, 2007


Global Warming is one of those topics that requires a discussion of “consensus”. This is what “most” scientists agree is correct regarding a particular topic. You may have heard that the consensus of the scientific community is that global warming (a rise in average temperature) is occurring and that human activity has some role in it. This does not mean that all scientists agree on this conclusion, as a blog post by a friend of mine shows.
“I have seen scientists who are otherwise reasonable people, drift right over the edge, and now I am completely fed up. Anthropogenic Global Warming is a hoax.”
Hawk is a legitimate scientist with a degree in nuclear engineering. He models space environments and radiation effects for NASA. To put it bluntly, he is a rocket scientist. To my knowledge, he has no conflict of interest or ulterior motive for disputing the scientific consensus that human activity is creating conditions that increase temperatures at the Earth’s surface. He cites computer models that indicate the amount of ice in Antarctica is actually increasing, not decreasing. There is every reason to think he honestly believes the scientific consensus on climate change to be wrong.

At the same time, NASA is releasing data from satellite observations that show a large mass of Antarctic ice recently melted away.

Scientific consensus is a changing beast. Scientists are constantly collecting and analyzing new information in an effort to build a more accurate description of the universe. Different scientists look at different data sources, and they don’t all necessarily have the same picture based on their information sources. The opinion of any one scientist on a particular matter can easily be wrong; that’s why scientists are so keen to see original data and methods included in published scientific papers. One of the basic principals of the scientific method is to repeat experiments to verify the results, checking each others' work.

Hawk is an extremely intelligent man, and far more knowledgeable than me in many fields. That said, his is not a climatologist, so he is not as prepared to validate a given climate model as someone specialized in that field. Furthermore, he is in the minority in the scientific community. One man’s dissent in a community of thousands is not grounds to ignore a potentially serious problem.

Hawk himself does not dispute the prediction that the Arctic Ocean may be completely ice-free in the summer within ten years, and his update to the article shows that the ice-growth model he cites has a limited scope. It shouldn’t surprise us to find ice accumulating in some areas, but that does not necessarily mean that the overall quantity of glacial ice in the world is increasing.

If most scientists agree that global warming is a matter of concern, it behooves us as a society to accept at least the possibility that our activities are changing the planet and consider what we can do to mitigate such changes. Future studies may show that the current concern is unwarranted, but a little caution now may save a lot of pain in the future, as well.

No comments: