Climate Change Today: Not a Natural Cycle

One of the arguments that many climate science deniers use to deny that modern climate change is a man-made problem is to characterize it as just a natural cycle. That argument helps maintain the veneer climate science deniers need to reject or downplay climate change as a serious problem. In a short article, Climate Clincher, Scientific American summarized a paper published in July showing that current climate change is not part of a natural cycle.

Researchers analyzed 210 data sets of various ways to measure temperatures such as lake sediments and glacier ice for the last 2000 years. The results show that the current warming is unlike every past period of warming and cooling because all data sets show warming now everywhere on Earth. In past warming or cooling periods, there were always some indicators showing warming and some showing cooling. The current data shows only warming almost everywhere on Earth’s surface with few areas of cooling. That is unprecedented for the last 2000 years. It constitutes evidence that this period of warming is not part of a natural cycle.

Despite the Climate Clincher title, this data is unlikely to change many, if any, climate science denier minds. This topic is impervious to evidence or logic for people inclined to reject the political implications of anthropogenic climate change. Just as satellite data analysis showed warming to a high degree of confidence changed few or no minds, this new analysis is unlikely to make any noticeable difference in terms of government attitudes or policy. That data showed there is only about a 1-in-3.5 million chance (a ‘five sigma’ level of confidence) that the warming currently observed is due to random chance instead of human activity. That standard of confidence is what physicists require to accept as real a fundamental new finding such as the Higgs boson.

This new data analysis will not turn out to be a climate clincher for people who deny climate science. Nonetheless, for people with the moral courage to actually face reality for what it is, it doesn't hurt to have another bit of evidence that climate science is not making a huge mistake.