The Coastal Post - May 1999

New Effects of Ozone Loss; The List Keeps Growing

By Jim Scanlon

The ozone layer is usually described as "the Earth's protective shield that stops harmful ultraviolet radiation from the sun from reaching the surface of the earth." Although we are bombarded with information on ozone loss we rarely receive any information on increases in "harmful" ultraviolet radiation and zero about actual present day harmful effects. Does this sound scientific, or even minimally reasonable?

To make matters worse, ozone does many other things in our stratosphere which are consistently reported in specialized scientific publications, but never make it into the general public consciousness.

Last year scientists at Goddard Institute at Columbia University caused a stir in the scientific community when they published a thoughtful study in Nature Magazine, connecting the sporadic massive ozone losses over the Arctic in the 1990s, with structural changes in the atmosphere brought on by "global warming." Their work prolonged the period of maximum danger from increased ultraviolet radiation by forty years, yet there was little to no mention of it in the general media.

One would have expected that the connection of massive ozone loss and delayed recovery with CO2 emissions would have affected the conference in Kyoto on limiting these emissions but strangely, it did not.

One would also have expected that the Managers of the Montreal Protocol might have taken note of the problem and stepped up efforts to limit the production of ozone depleting substances still being manufactured or to begin considering destruction of stocks of these substances. They have revised the treaty several time, but, this year-nothing!

What, to the Coastal Post is most alarming about the Goddard study is that it describes changes in the actual structure of the atmosphere-the way giant air masses rise and descend, the way rivers of air move about the planet as having taken place-not in 2050 but-yesterday, now! This does seem like something important.

So far there have been three peer reviewed specialized studies by recognized experts from prestigious institutions supporting and strengthening the study. It's as if scientific commentators are holding their breath.

It is not as if the temperature of a building has been raised a little on some floors and cooled a little on others, but as if the ventilation system that was there was taken apart, reassembled and was operating differently! If this happened in reality, the Building and Health Departments would want to know what was going on.

Now, on April 8, 1999, the same Goddard Institute scientists (with two new authors) published another study, this time in Science Magazine, demonstrating the vital importance of ozone in the transfer of small increases in energy from the sun from the upper atmosphere to the lower atmosphere and thus changing climate on the surface.

And or course, if there is less ozone to trigger the transfer, there is less energy transferred and so, the climate changes.

Our sun has a well defined cycle of 11 years, but at it's maximum output of energy, the increase is just 1 percent, which doesn't seem to affect the earth's climate very much. But 10-20 percent of the solar increase is in the ultraviolet and ozone adsorbs ultraviolet very efficiently. Additionally, because of the tilt of our planet and the shape of our orbit, the Southern Hemisphere is a little closer to the sun during its summer and receives a little more energy from the sun than the North.

One can see how this study connects with the previous study by the way the authors connect the adsorption of solar energy in the upper stratosphere by ozone which alters stratosphere winds which affect planetary waves which transfer heat on massive scales down to the lower atmosphere.

Last year the authors proposed that increases in strength of stratospheric winds as a result of "global warming" prevented planetary waves from warming the Arctic as efficiently as they had in the past, allowing for colder temperatures for longer periods, which allowed clouds to form which make possible highly efficient chemical reactions that activate chlorine which destroys ozone catastrophically.

What the Goddard scientists seem to be saying is that the reason why the Springtime Arctic Ozone Hole does not happen every year is influence by variations in ultraviolet radiation during the Solar Cycle which affects ozone (which we are changing) which affects stratospheric winds, which affect planetary waves, which affect weather patterns that affect temperature which affects ozone which affects ultraviolet.

It is a complex change. Are they right? Who knows? The changes have occurred and they offer a plausible explanation for the observed changes. Are they on to something hot? It would seem so from the number of papers and discussion on "Planetary Waves" now appearing.

No one at the Coastal Post is incapable of evaluating the complex detailed statistical analysis involved in the latest paper, but the conclusion seems obvious, changes are occurring, even if they are being ignored.

The Southern Hemisphere is worse off. Last year's Antarctic Springtime Ozone Hole, which used to end at the end of October, lasted till almost Christmas and ozone levels were lower than normal during the summer and fall of the Southern Hemisphere. There was abundant ozone over the Arctic this spring and last, but the three years before that were low, with losses almost as great as over Antarctica.

During my visits to South America I found people generally more concerned about climate change which has serious consequences for their economies dependent on agriculture. I spoke recently with a friend who lives along the Straight of Magellan who said there were not too many problems with ultraviolet this fall despite low ozone levels because of unusually heavy cloud cover. But, the weather was out of sequence with unusually strong winds out of season.

Chile is again experiencing a sever drought with less snow being deposited over the Andes. There are presently power black outs for lack of snow melt runoff for hydroelectric power generation

As the above studies suggest, these changes may be interrelated. We live in, after all, just one world and we don't seem to be taking good care of it.

Coastal Post Home Page