Global Warming and Greenhouse Gases :: Environment Environmental Pollution Preservation

Global Warming and Greenhouse Gases    With all the talk about the global warming and climate change, including international debates focused on the viability of reduced gaseous emissions, one centrally-important consideration often gets ignored. It turns out that the greenhouse gases that contribute to warming the earth constitute only about 1 percent of all gaseous atmospheric material. And if one considers only the subset of these gaseous molecules whose concentrations are thought to be altered by human activities, their atmospheric contribution drops to well below 1 percent. In the past 50 years we have begun to realize that these additions to our atmosphere, which come primarily from fossil fuel burning, will likely have significant impacts on human and ecosystem health and welfare. Simply put, these ''new'' gases, despite their low relative concentrations, have and will continue to demand our attention from political and economic points-of-view. Remarkably, albeit so small in percentage terms, greenhouse gases are critical to our maintenance of a planetary atmosphere conducive for life. Recognizing how such a minute portion of our atmosphere affects humans so significantly is a first step towards understanding why seemingly small quantities matter and likely a requisite step for living in a sustainable way. (Quantities are small in relative percentage terms, but in net emission terms, the U.S., alone, emitted a staggering 89 billion pound of CO2-equivalent greenhouse gas in 1998!) Probably the resource most taken for granted in this world is the air, particularly the oxygen that we breathe. Most of us could last several weeks without food and a few days without water, but very few of us can survive for more than minute or so without air. Both humans and animals need a constant supply of oxygen or our bodies shut down. Thankfully, the atmosphere is plentiful with this resource. Currently, the oxygen (chemically, O2) that we require takes up nearly 21 percent (by volume) of the air that we breathe; most of what we breathe in is nitrogen (N2, dominant to the tune of 78 percent) which, strangely enough, has little known purpose ingested into the body in gaseous form. Now while this vital resource is found in relative abundance, other essential gaseous resources are much less common.