Air

Air is our most essential requirement for life. Without food or water, we may last a few days, but minus air, we expire within mere minutes. We are born into life with our first crying gasp, and our final exhalation is death’s sentinel. Given its vital importance, it is no wonder air has been considered by cultures the world over as one of the most sacred basic elements of the universe. The ancient Greeks believed that Khaos, the goddess of primordial air, was the origin of all existence. In Hinduism and ancient yogic traditions, Vayu (breath) is the key to purification and ultimate nirvana. In China, air is associated with chi, the very essence of life itself.

Modern Earth’s life-giving, oxygen-rich atmosphere is unique among known planetary bodies. Our nearest neighbors, Mars and Venus, have atmospheres largely comprised of carbon dioxide, methane gas and sulfur dioxide, and our own Earth once swirled beneath a similar blanket of gasses formed from the eruptions of ancient volcanoes.

As the earth cooled and oceans formed, anaerobic (oxygen free) conditions and a volatile atmosphere set the stage for the development of complex amino acids and primitive life forms. The earliest life forms were blue green algae or cyanobacteria, primitive prokaryotes (cells without nuclei) that live in oxygen free environments. As cyanobacteria photosynthesized, they converted atmospheric carbon dioxide and water into carbohydrates and oxygen. Eventually, earth’s oceans and atmosphere filled up with oxygen creating the conditions necessary for complex organisms to evolve.

The contemporary atmosphere is maintained by an intricate web of reactions between plants, other living organisms and the mineral compounds of the Earth’s crust. Like Baby Bear’s porridge, the atmosphere is delicately maintained in an equilibrium that is just right for life. Plants and algae absorb carbon dioxide from the atmosphere, combine it with water and a spark of sunshine and create carbohydrates and oxygen. The carbohydrates produced by plants are the basis of all the food webs on Earth, and the oxygen they produce is the vital constituent of the air we breathe. The freshness and revitalizing quality of the air in a forest is due to the higher concentrations of oxygen produced within the leaves of the multitudes of plants within the forest ecosystem.

Until humans began to dramatically alter the natural condition, Earth was completely covered in a mantle of vegetation. The vast quantity of plants competing for carbon dioxide and exhaling oxygen created the oxygen rich, climactically-stable atmosphere we enjoy today.

With the industrial revolution, humans began to slowly but surely alter the delicate balance of air on Earth. Anthropogenic burning of fossil fuels such as coal and gas now releases about 27 Gigatons of carbon dioxide into the atmosphere each year. The burning of coal releases sulfurous compounds and heavy metals into the atmosphere. The tail pipes of our cars add nitrous oxides, ozone, carbon monoxide, particulates and other volatile organic chemicals. Factories, refineries and industry supply a veritable stew of different emissions.

The effects of the incessant contamination of the atmosphere are not benign. Acid rain threatens forests and aquatic ecosystems. Chronic respiratory diseases such as asthma are at an all time high. Mercury and heavy metals contaminate fisheries stocks and threaten human health, and the alteration of the delicate balance of gasses in our atmosphere threatens to destabilize our climate.

At the same time we are pumping pollutants into the air, we are undermining the integrity of the natural systems that have the ability to undo our impacts. Half of Earth’s precious forests have now been lost (1), and all of Earth’s oxygen producing vegetation communities are being undermined by human activities.

Trees are cut down in the rainforest to clear land for cattle and to harvest lumber for homes. Millennia old forests are reduced to toilet paper. Mangrove forests and sea grass beds in the ocean are dredged and scraped clean of vegetation to make marinas for luxury yachts and waterfront homes. The tundra is decimated in the interests of the coveted black gold elixir. All of these activities result in goods for consumers to buy, and a few lucky capitalists get rich.

But, the old growth temperate forests, tropical rainforests, coastal mangrove forests, sea grass beds, savannahs, tundra and all the other plant communities of the Earth are much more than the monetary sum of their resource values. Clean, oxygen rich air does not have a market value. Apart from the new and trendy oxygen bars springing up in smog cloaked metropolises, the capitalist markets have yet to find a way to package and sell the commodity. Like many things of real value, our atmosphere is truly priceless. Without it, all else is definitely meaningless.

Yet we continue to blindly destroy the ecosystems of the earth to harvest resources and line our pockets with dollars that have a worth nature cannot utilize to make more air. While we are chomping on our fast food hamburgers harvested from the rainforest, enjoying the sterile waterfront view from our luxury homes and wiping our butts with venerable trees, we will literally be choking on the excess of our shortsighted stupidity.

References
1- Speth, J.G., 2008. The Bridge at the Edge of the World. Yale University Press, New Haven, CT (Kindle edition, location 122-25).

Further Reading
http://eesc.columbia.edu/courses/ees/climate/lectures/earth.html
http://www.ux1.eiu.edu/~cfjps/1400/atmos_origin.html
http://www.pacificislandtravel.com/nature_gallery/atmosphere.html