Anthony Watts has reposted an interesting article by Leonard Weinstein ScD that lends perspective when considering the assertions of the Anthropogenic Global Warming (AGW) lobby. Dr. Weinstein's paper is useful reading if you care to be better informed on the disputes raging in the scientific community and better understand the push back by scientists unconvinced that present changes in climate provide a rationale for the draconian changes in energy use and sources already disaffecting the third world. editorFollowing are some excerpts and a link to Dr. Weinstein's article:
It is not obvious what the ideal temperature and CO2 level should be for mankind. We tend to assume that the average of whatever has occurred in the recent past is the ideal level, since we have adjusted to that level, and changes from that level can cause disruptions in living conditions and activities. Significant temperature and CO2 increases in recent years have raised the issue of whether these were possibly related and were due to human activity, and whether this is a potentially significant problem.
The AGW proponents claim that the magnitude and level of the present global temperature, and the speed in which it increased, is unusually extreme and cannot be accounted for by natural variations. They claim the observed temperature increase is being caused by human activities...
In order to examine the AGW claims, temperature data is shown in figure 3 [go to linked article] from three widely separated sources. The data covers the last three thousand years. Conclusions from these curves are:
1. The temperature varied several times over the period by 1.5 degrees C to 2 degrees C for all three curves
2. Temperature variations occurred fairly rapidly, with typical time scales of 50 to 200 years
3. The rise rate over the last 150 years is not unusual compared to other rise rates
4. The present level of temperature is near the average for the curves shown for both Northern hemisphere cases, and below several previous peaks
5. The “Little Ice Age” and “Medieval Climate Optimum” show up in both Northern hemisphere cases
6. The present temperature is not unusually high for the Antarctic
go to Weinstein article