There may be some serious scientists that doubt that global warming exists or has a human cause, but there may not be any that side with Singer on the ozone question. Who, for example, seriously thinks UV radiation doesn't cause skin cancer?
Sorry about the "shifting ground" confusion. Let's try to straighten it out.
Singer does NOT doubt that CERTAIN BANDS of ultraviolet radiation can cause skin cancer. Rather, he says argues that the chain of causation, beginning with increased CFC emissions, and ending with increased human skin cancer, is faulty.
There are 2 relevant bands of ultraviolet: UV-A and UV-B. UV-A causes "malignant melanoma", an often fatal form of skin cancer. UV-B causes the non-malignant form of cancer: i.e., you don't die from it.
Singer's points out that UV-A (the ultraviolet radiation which causes deadly cancer) is UTTERLY UNAFFECTED by ozone. The hole he pokes in the EPA argument for the Montreal Protocol is that:
* ozone depletion, if it were to occur, will not make more UV-A reach the earth's surface * if no more UV-A reaches the earth's surface, people won't be exposed to more of it and thus people WILL NOT die more often from skin cancer.
Hope this clears this up. This info should go into the [[ozone depletion]] article, if it's not there already.
Ed Poor