Getting Climate Worries into Perspective

Here's a bit from a very nice essay by MIT's atmospheric physcist and lead author of IPCC's Chapter 7, 'Physical Climate Processes and Feedbacks', Richard Lindzen. He is telling people to not fall for the doom-and-gloom hysteria about climate change being pushed by the climate modeling community:

The notion of a static, unchanging climate is foreign to the history of the earth or any other planet with a fluid envelope. The fact that the developed world went into hysterics over changes in global mean temperature anomaly of a few tenths of a degree will astound future generations. Such hysteria simply represents the scientific illiteracy of much of the public, the susceptibility of the public to the substitution of repetition for truth, and the exploitation of these weaknesses by politicians, environmental promoters, and, after 20 years of media drum beating, many others as well. Climate is always changing. We have had ice ages and warmer periods when alligators were found in Spitzbergen. Ice ages have occurred in a hundred thousand year cycle for the last 700 thousand years, and there have been previous periods that appear to have been warmer than the present despite CO2 levels being lower than they are now. More recently, we have had the medieval warm period and the little ice age. During the latter, alpine glaciers advanced to the chagrin of overrun villages. Since the beginning of the 19th Century these glaciers have been retreating. Frankly, we don’t fully understand either the advance or the retreat.

For small changes in climate associated with tenths of a degree, there is no need for any external cause. The earth is never exactly in equilibrium. The motions of the massive oceans where heat is moved between deep layers and the surface provides variability on time scales from years to centuries. Recent work (Tsonis et al, 2007), suggests that this variability is enough to account for all climate change since the 19th Century.

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Climate alarmists respond that some of the hottest years on record have occurred during the past decade. Given that we are in a relatively warm period, this is not surprising, but it says nothing about trends.

Given that the evidence (and I have noted only a few of many pieces of evidence) strongly implies that anthropogenic warming has been greatly exaggerated, the basis for alarm due to such warming is similarly diminished. However, a really important point is that the case for alarm would still be weak even if anthropogenic global warming were significant. Polar bears, arctic summer sea ice, regional droughts and floods, coral bleaching, hurricanes, alpine glaciers, malaria, etc. etc. all depend not on some global average of surface temperature anomaly, but on a huge number of regional variables including temperature, humidity, cloud cover, precipitation, and direction and magnitude of wind. The state of the ocean is also often crucial. Our ability to forecast any of these over periods beyond a few days is minimal (a leading modeler refers to it as essentially guesswork). Yet, each catastrophic forecast depends on each of these being in a specific range. The odds of any specific catastrophe actually occurring are almost zero. This was equally true for earlier forecasts of famine for the 1980's, global cooling in the 1970's, Y2K and many others.

So relax. Don't let the Chicken Little's worry you. The world will go on. There is no ultimate catastrophe lurking around the corner.