Climate debate heats up

Too much space was spent on global warming in the May-June 2002 issue. The editorial points out how little we know about global climate change. The authors also say that global climate change will occur in longer periods than 50 to 100 years. Faced with that uncertainty they propose we should “emphasize measures that reduce the apparent driving forces behind global climate change.” The “scientists” pushing the global warming idea never seem to consider factors such as increased output of energy from the sun or subtle changes in the earth's orbit. They concentrate on activities of man as the driving force. The earth has been much colder (glaciers) and warmer than it currently is. Industrial mankind wasn't around for those changes. I suggest we recognize that global climate change occurs but science hasn't yet discovered all of the possible causes and certainly can't interpret the interactions of all the possible causes.

Bryan Weare (“Global climate change will affect air, water in California,” Cal Ag 56(3):89-96) responds:

The reader states that scientists “never seem to consider factors such as increased output of energy from the sun or subtle changes in the earth's orbit.” This is incorrect. The Hadley model, as well as many others, has taken into account our best understanding of solar output changes over the time frame of decades to centuries. Solar orbital changes work only on much longer times of many thousands of years.

Second, the reader notes that the earth's climate has been colder and warmer than it currently is, and that these changes occurred long before industrial mankind. Nothing in the review article suggests that climate change does not exist on longer glacial time scales. However, human activity is apparently leading to relatively large changes in climate at a rate much faster than has been seen in the recent geological past or is likely without human intervention. Of course climate is always changing. The important policy factor is whether or not the rate of change is exceeding our ability to accommodate it without large disruptions in our social and economic institutions.