Ozone Anxiety
by Michael Hofferber
Copyright © 1992. All rights reserved.


The sun rose clear this morning and sparkling against snow-packed lanes and frosted mountains, so bright that it hurts the eyes.
   
It is a distant sun this time of year, cutting just a small arc across the southern sky. Some days it seems to hardly make an appearance, but when it does the brilliance is almost blinding.
   
Sunglasses were made for days such as this, and sunscreen to guard the skin. Sadly, the radiant glow from our heavenly neighbor, so welcome this time of year, is also deadly.
   
Frogs and salamanders are dying from too much sun, or at least that's what some herpetologists believe. All around the globe amphibians are disappearing, suddenly and unexpectedly, and there is evidence that a decay in the Earth's ozone layer may be causing the decline. 

"The Celebrated Jumping Frog of Calaveras County," a red-legged leaper common in the 1860s when Mark Twain wrote his famous story, is now gone, vanished from its namesake territory. In Colorado, tiger salamanders are becoming scarce. In Cameroon, the Goliath frog is nearly extinct. And in England, the common toad is now uncommon in many places.
   
Biologists' field studies report similar disappearances in South America, Australia, Europe and Asia. Amphibian populations are crashing.
.

Acid rain and industrial pollution are blamed in some places; drought has contributed in others. But even in theCascade Range of western Oregon, which has none of those problems, a population of Western toad that has been studied for 20 years is suddenly in deep trouble..
   
Could a depletion of the ozone layer, which absorbs ultraviolet light from the sun (UV-B radiation), be affecting these creatures? Although there's no hard evidence of cause and effect, it is known that the moist,soft-skinned amphibians and their eggs are vulnerable to increased radiation. They have no Vuarnets to slip on or Sun-blocker to protect their hides. If the UV-Bs get through to them, they die.
   
Since it was discovered in 1985, the hole in the ozone layer over Antarctica has been well publicized. And most of us accept the fact that chlorofluorocarbons (CFCs) used in refrigerators and aerosal cans are largely to blame.
   
What is not as well appreciated is the fact that the ozone layer is thinning all across the planet, and not just over the South Pole. It's 5 percent thinner overhead here in the U.S. than it was just 10 years ago, according to NASA scientists, and still shrinking.
   
If toads in Oregon have already felt the change, then it stands to reason that we are all endangered. Sensitive skins may suffer first, but none are safe. Anyone who works or plays out-of-doors has got to be concerned.
   
Who can feel comfortable when creatures that survived 250 million years -- outliving the dinosaurs and many other creatures -- are cashing it in all around us?


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