Is There an Increasing Trend in Ultraviolet Radiation at the Earths Surface?
In spite of the fact that a downward ozone trend should result in an upward trend of UV, no such trend has ever been reported. In November 1993 two Canadian researchers, J.B> Kerr and C.T. McElroy, published a paper in Science claiming to have measured large upward trends of UV, as much as 35 percent per year for certain wavelengths. Their results were deemed suspicious since they showed no error bars or other measures of uncertainty. Indeed, a re-analysis of their data, also published in Science, showed that the “trend” was consistent with zero percent. The Kerr/McElroy paper created great excitement. Even though they no longer claim the existence of a trend, researchers in other fields continue to blame a UV trend for such things as the disappearance of frogs and the rise in melanoma skin cancers. Ignored is the undisputed fact that UV increases strongly as one approaches the equator; the feared 10% increase due to ozone thinningif it were to existwould correspond to a 60 mile move t
