I would like to submit four questions to the debate on global warming:
Â
1. What caused the global warming that ended the last ice age approximately 12,000 years ago?
Â
2. What caused the short global warming episode less than a thousand years ago when the Norsemen grew crops in Greenland, which later became too cold to support it?
Â
3. I have heard from people who study such things that carbon dioxide is one of the more transparent gasses in the atmosphere, as shown by spectrographic measurements. How is it, then, that a small amount of relatively transparent gas can have such an overwhelming effect on the atmospheric temperature?
Â
4. Are the Earth’s weather systems adequately represented in the studies that have lead to the global warming scenarios that we read about in the media?
This article appears in May 7-14, 2009.