Kathy Andrykowski, age 12, of Milwaukee, Wisconsin, for her question:

Is there really plant life in the clouds?

Now and then, somebody reports a shower of baby frogs. Some scientists suspect that this may be possible, though chances are the reports are highly exaggerated. However, weather experts are certain that microscopic forms of both plant and animal life are quite common in certain clouds. Many are spores and other dormant cells. But recent research suggests that some  cloud populations may actually thrive and multiply during their high flying vacations.

When we observe the billowy pillows of a thunderhead, we prepare for a deluge accompanied by rumbling sound effects and vivid flashes of lightning. To a cloud physicist, this cloud is a cumulonimbus governed by dynamic weather forces. Chances are, he also speculates that it may support an airborne system of ecology. Recent evidence suggests that this may indeed be true and at the present time researchers are busy probing to prove the theory true or false.

To qualify as an ecosystem, an environment must support an assortment of living, thriving and multiplying populations. We know that spores, pollens and other life forms are wafted aloft by updrafts and exist high above the ground. In the dormant stage they do not qualify in an airborne ecology, even though they arouse and continue their life cycles when returned to the earth.

Now other microorganisms have been found in the clouds and researchers sugp_est that a cumulonimbus could support a thriving ecosystem. Sample cloud populations include fungi, microscopic plants, and midget members of the animal world. Some have life cycles with no dormant phase. If they do form an airborne ecology, the cloud must provide its tenants with moisture, nutrients and sunshine.

We know that it provides moisture which may tend to condense on microorganisms. It provides sunshine, softened by a hazy mist that also filters out harsh ultraviolet radiation. It also contains gaseous molecules of such basic nutrients as oxygen and carbon dioxide, methane and other hydrocarbons, heavier nutrients, including phosphorous and potassium, are hoisted aloft on particles of dust.  It seems likely that a cloud could support a thriving ecology, at least for a while. But the life span of a thunderhead lasts only a few hours and not many clouds exist longer than two or three days. However, many midget organisms live on midget time schedules. Many clouds exist long enough for certain algae to complete several cell divisions. If they do indeed thrive in a thunderhead, many of them parachute down with the falling raindrops    and continue life on the ground.

This fascinating investigation was triggered by rain bearing vitamins and other substances created only by living things. It seemed possible that these biochemicals are created in the clouds. If this proves to be true, the mysterious activities of cloud populations may help us to solve some of our atmospheric pollution problems.