An essay concerning our weather.

Mike Keefe drew a cartoon in the Denver Post that perfectly portrays a prevailing attitude toward our rogue weather. The cartoonist shows a man pointing at a calendar and yelling at the thunder clouds (or God?): "What? You having trouble with the small print? The calendar says it's spring, dammit!" It makes me wonder who's really having trouble with the small print.

When was the last time any of us has truly reflected on what drives our weather? Our atmosphere is the product of more than four billion years of ongoing evolution - geologic as well as biologic. It's a tenuous veil of gases that lays upon the surface of our planet, like the finest silk upon your skin. This veil has a most interesting structure, which I want to describe.

Our atmosphere is composed almost totally of nitrogen and oxygen. Interwoven into this medium is a gossamerthin admixture of everything else: thousands of different compounds which can be grouped into almost 200 distinct families. Combined, these compounds make up less than one percent of our atmosphere's volume. Most of this volume is made up of inert compounds and noble gases, so called because they don't react with their surroundings very much, if at all. Within this matrix of nonreactive molecules is another, yet thinner community of reactive compounds. By volume, these reactive elements consist of around 0.036 percent or 360 parts per million parts of the sky. This is where the action is. These chemicals are always reacting with each other: they combine, split up, mutate, affect neighboring molecules, change characteristics - and they do this at nonstop hypervelocities. This is the scaffolding over which energy, moisture, and heat perform their weather ballet.

Back to the small print in our current weather story. What's new is that, over the past 100-plus years, humanity has been injecting a third category of ingredients: humanmade and human-generated. By volume, this new genre consists mainly of substances already present in the atmosphere, only now they're being unleashed in unfathomable quantities; they belong to the reactive families. Then there are the exotic varietals. Creations of science and industry, they make up a small but usually highly reactive percentage. Most of these compounds are totally new to the atmosphere. All told, society has been injecting millions upon millions upon millions of tons of these gases and particulates into our atmosphere at an ever-increasing rate, so much so that the very composition of our atmosphere - the weave of our atmospheric veil - has been significantly altered.

This is of interest because our atmosphere is in actuality a heat engine. Its matrix of gaseous and particulate components are the valves and pistons. This engine is driven by the sun's energetic rays. The result is our weather: the global distribution of energy, heat, and moisture. The small print is that each compound we've introduced interacts with the sun's energy according to its own unique thermo-hygroscopic-chemical profile. It seems that recent weather fluctuations are nothing more than a physical reflection of how we treat our biosphere.

Remember all those silly environmentalists whining about pollution, global warming, and all that? It isn't all delusions! Scientists have been discovering and recording these changes since the end of World War II. For the past 30 years, satellites have been visually recording the stains, rips, and acid burns that we are inflicting upon the veil of our atmosphere. The increasingly sophisticated information they gather continues to have ominous implications for the future as well as the present.

Why be surprised when weather continues to become more chaotic? Admittedly, no one can accurately predict how weather will change. But who can deny that it will continue to change, and at an accelerated rate? Maybe we're the ones who should be reading the small print: humanity's usage of this Earth, Gaia, is like any other economic agreement. Sooner or later you have to pay the piper; sooner or later you pay the consequences. We can kid ourselves, but we can't fool Mother Nature.

Peter Miesler is a freelance writer from Denver, Colorado. This cartoon originally appeared in the May 26, 1995, Denver Post and is reprinted with permission.