The greenhouse effect, global warming, and climate change are terms used to describe different aspects of the warming of the Earth's atmosphere. Our concern must be that human activity alters the composition of the atmosphere rapidly in ways that could bring on profound changes in our climate. Most of the human race is found in Africa, Asia, and Latin America -- the Third World nations. Yet, three quarters of the greenhouse gases are generated by North America, Europe, and the Pacific Rim which houses only twenty percent of the World's population. The Third World will be the first to be overwhelmed though many of these countries contribute little to the global warming.

The greenhouse effect is the natural process by which certain gases in atmosphere allow the sun's radiation to pass through to the earth. Without the greenhouse effect, heat would quickly radiate back into space leaving the planet with a temperature close to zero degrees Fahrenheit. Water vapor and traces of carbon dioxide act like an insulating blanket. Without this action, the greenhouse effect would build indefinitely and irreversibly.

Greenhouse gases trap the infrared heat reflected from the sun-warmed earth and redirect much of it back to Earth's surface, somewhat like panels of a greenhouse. Molecules of carbon dioxide, methane, water vapor, and other gases are highly sensitive to infrared energy. The warming effect of the other greenhouse gases mentioned is expected eventually to equal, if not exceed that of carbon dioxide.

Global warming means a rapid change and rapid change means the end of familiar places. Familiar trees will vanish and creatures will scatter. Weakened marshes will be drowned, beaches will disappear, and streams will dry up. Storms and floods will eat the land from our homes so places will cease to exist. Nature can no longer be protected and preserved. A legacy will be left to our children of only nature's bones to pick from and will justify contempt for the selfish generations before them.

Early human societies experienced a cold climate, a glacier or ice age extending until about ten thousand years ago. Before that the earth was ice-free and far warmer than today. A medieval warm epoch occurred between years 800 AD and 1250 AD in which the global temperature was similar to today, soon followed by the "little" ice age from 1550 AD to 1850 AD. Around 1900 AD the Earth swung into a natural warming trend, the seven warmest years being: 1990, 1988, 1981, 1987, 1983, 1980, and 1989.

The temperature of earth is determined by the balance between the rate at which sunlight reaches the earth's surface and the rate at which the warmed earth sends infrared radiation back into space. It does not respond in a smooth and gradual way but in sharp jumps. Linked with the Earth's other components, the oceans, soil, sheets of polar ice, the flow of energy from the sun, and the web of life, the atmosphere has always acted as a green house.

The interplay and balance of the biosphere, oceans, rock, air, and ice of Earth has kept conditions congenial for life for billions of years. Though significantly altered by human actions, the atmosphere appears unchanging, presenting a paradox, in constant flux yet remarkably predictable. A global temperature increase would have a profound effect on our climate, altering weather patterns and affecting air and ocean circulation.

The formation of the ozone layer millions of years ago enabled life to leave the protection of the sea. A stratospheric ozone layer protects life by shielding the earth. Ozone is defined as a layer that effectively absorbs the destructive energy of the sun's ultraviolet radiation. The action of sunlight on oxygen molecules constantly creates this ozone. This ozone is thickest and lowest over the poles and reaches its maximum altitude in the high stratosphere over the tropics where most of it is produced. Now this layer is being sapped by synthetic chemicals manufactured by man, one of the species that resulted from life's first emigrant ashore.

Over time, chlorine atoms from relatively few decomposed chlorofluorocarbons (CFC's) can destroy more stratospheric ozone than the sun can create. The ozone produced on earth cannot be used to replenish the layer in the stratosphere, having a limited life span before combining into other chemical substances. Ground-level ozone qualifies as a greenhouse gas and is very toxic. It is formed by the action of sunlight on nitrogen oxide and hydrocarbon pollutants (smog) emitted primarily by cars and trucks.

The depletion of ozone layer increases the amount of ultraviolet radiation (UV) reaching the earth. This has potential effects on human health, leaving people risking skin cancer, cataracts, and alterations of their immune system. The ozone and acid rain on the ground level, simultaneously causes destruction of the primary filter of UV light.

Other planets in the solar system illustrate the significance of the greenhouse effect. Venus has a dense atmosphere that is mainly carbon dioxide. Its sterile surface sizzles at eight hundred ninety degrees Fahrenheit. Mars has a thin atmosphere that has little greenhouse effect. Its average surface temperature is colder than that of Antarctica so what water exists is in a perpetual deep freeze. Earth literally and figuratively lies between these two extremes. Cloaked in an atmosphere with sufficient water vapor and carbon dioxide to retain some heat from the sun, its temperature lies comfortably in the range in which life can flourish.

In recent years, unnatural agents such as increased concentrations of carbon dioxide, nitrous oxide and other greenhouse gases are changing the atmosphere's natural thermal blanket. Many variables make predictions uncertain, such as increases in heat trapping gases. We only know that as the gases continue to accumulate in the atmosphere, the earth will continue to warm.

The atmosphere is supposed to do two things for humanity --maintain a constant chemical climate of oxygen, nitrogen and water vapor and help maintain the radiation balance. Michael Oppenheimer suggests these changes are going to effect every human being and every ecosystem on the face of the earth. The result may be a new mass extinction such as ended the era of dinosaurs.

The full extent of warming accompanying any level of greenhouse gases is only realized about forty years after its release into the atmosphere. The effects of a global warming over the next half century may cause rises in sea level, changes in winds and ocean currents, accumulation of ice and snow in polar ice caps, and frequent severe storms. Warmer oceans would spawn more frequent and stronger hurricanes and typhoons. The ocean slows down the rate of warming because heating the great mass of water takes very long time. Larger waves and storm surges would come on top of a higher mean sea level.

Variations in the range of disease bearing organisms and droughts affecting water availability and agriculture may occur. Changes in our woodlands, forests and other natural ecosystems, including forest fires, will cause an increased extinction of plant and animal species around the world. It is estimated that two to five percent of the planet's land surface burns each year, adding to the greenhouse effect.

Mankind is shifting the chemical balance bringing poisons into the atmosphere at unprecedented rates. These gases vary in their concentration, their ability to absorb heat, and their life span. Their concentration closely relates to changes in the Earth's surface temperature. Certain trace gases in the atmosphere absorb heat radiating from the Earth and emit some of it back to the surface, raising the temperature. Melting glaciers and ice sheets and thermal expansion of the upper layers of the ocean will cause the sea level to rise by one to three feet during the next century. To date, the global surface temperature has risen one degree Fahrenheit and could climb at a substantial clip of one-half to one degree per decade.

Most of the sun's energy travels to Earth as visible light, but some enters the atmosphere with the purpose of warming things up. Surfaces warmed by the sun then begin to shed that accumulated energy as heat. Air currents provide an important means for redistributing solar energy. The tropics absorb more solar energy than the polar regions.

Conversion and storage take place naturally when the sun heats the Earth's surface and evaporates water from the ocean. The warm air condenses into clouds and falls as rain or snow. The clouds and oceans bring about a warmer climate that leads to a cycle of increased evaporation and cloud cover. Clouds routinely cover about half of the Earth. They strongly influence our climate, both by trapping some of the planet's heat and by reflecting sun rays from their white tops. They both warm and cool the planet's surface: high clouds trap heat, low clouds reflect it. Thus, clouds exert a greenhouse effect of their own. Both the reflective effect and the greenhouse effect of clouds are largely compared with the greenhouse effect of carbon dioxide and other trace gases in the atmosphere.

Because of warm, moist air penetrating into the high altitudes, a doubling of atmospheric carbon dioxide or the equivalent can cause a one foot rise in the sea level. The ocean is an exhaustible magazine, adapted for many beneficial purposes and carrying twenty times the volume of water flowing through all the world's rivers. This system, which covers about three fourths of our planet, holds the greatest single climate feedback data. How changes in the ocean temperatures will affect its currents, and so our climate, cannot be predicted, yet what is predictable is that these changes strongly affect the blooms and die-offs of plankton and other sensitive marine species.

The largest effect on the coastline of Georgia, South Carolina, and Northern Florida is tide level. More frequent hurricanes will bring erosion, causing coastal dunes to disappear. With the dunes gone, higher sea levels will seep increased salinity into drinking water, river deltas and estuaries, and flooding of woodlands, cypress swamps, adjacent lowlands, and populated areas.

The ocean acts as a buffer for global climate change and as a sink for some carbon dioxide emissions. The world's oceans contain fifty times as much carbon dioxide as the atmosphere does, and they absorb more than they release. The role of the oceans in taking up or supplying atmospheric carbon dioxide is another key uncertainty to modeling greenhouse effects. It is up to a few trace gases, water vapor, carbon dioxide, and methane, to keep the planet cozy.

Ecosystems, which consist of soil or water, plants, and animals particularly suited to interact with and sustain each other, would be disrupted or destroyed by rapid changes in the environment. Those that cannot adapt quickly may be exterminated. For example, forests play an essential role in storing and recycling the earth's carbon. Trees are highly sensitive to small variations in temperature and precipitation and would be victims of excessive warming and droughts. Tropical rain forests, crucial reservoirs of biological diversity harboring a vast array of endangered species, are also in jeopardy. The woodlands would cease to provide nesting and wintering grounds for fowl, spawning and nursing areas for fish, and the natural treatment for waterborne and airborne pollution.

Another ecosystem, the wetlands, serve as a vital biological factory in supporting the diverse coastal species. If the seas rise and warm as a result of global warming, the habitat and food supplies of coastal species might also be threatened. Animals would encounter great difficulties finding new habitats in our developed country. Migratory species might no longer find the necessary environments (such as wetlands) on their routes and at the end of their journey. Many vulnerable species may face extinction.

As problems of unrestrained development occur, environmental degradation, resource depletion, and severe economic and public health consequences result. Drinking water sources become threatened, and valuable land erodes. The open space and farmland base is reduced, and we lose valuable wetlands. Increased warming will weaken mankind's health, leading to more strokes, heart attacks, and related diseases. Warmer air would also speed up chemical reactions producing urban smog, encouraging respiratory diseases and lung cancer.

Air pollution and acid rain also cause adverse effects on human health (resulting in lost workdays), kill wildlife, and cause corrosion of buildings and infrastructure. In changing the composition of the atmosphere, humans may produce a very rapid climate shift for all life on Earth. This means that hurricanes, blizzards, thunderstorm, cold spells, tornadoes, drenching rains, and blistering heat waves will play out a life/death drama across the land.

The Earth will become warmer and warmer for an indefinite period if greenhouse gases emissions continue at their present rate. The lag time between this air pollution and its irreversible effects requires immediate action. Even if the emissions of gases were reduced enough to stabilize them at today's levels, it would take the Earth's temperature decades to level off. Less air pollution will generally mean a slower growth of other greenhouse gases giving five direct benefits -- less carbon dioxide, carbon monoxide, sulfur dioxide, nitrogen oxides, and hydrogen carbons. These in turn produce three indirect benefits: less acid rain, tropospheric ozone, and methane.

One inexpensive method to slow warming is to plant fast-growing trees over large areas. Along with this, man should minimize deforestation. With global cooperation, this solution might be possible. Individuals can help by planting trees in towns, cities, and in the country. Trees provide benefits by holding soil, preventing runoffs, providing shade, windbreaks, habitats for wildlife, and shade buildings thereby reducing demand for air conditioning.

Global warming retardation can also be achieved by controlling the burning of fossil fuels. Instead of providing tax write-offs and rebates for clean energy use, the government currently gives fossil fuels subsidies and incentives. Slapping a levy onto the price of fossil fuels would discourage combustion and encourage efficient and renewable energy use. For example, a surcharge could be placed on coal and natural gas purchases, weighted for the amount of greenhouse gas each produces.

States should develop land use and transportation plans to limit air pollution and greenhouse gases. Adequate mass transit and environmentally benign regional planning are impossible without each other, and each makes the other easier to achieve. Government should also make investments in energy conservation tax-deductible. These should include weatherstripping, insulation, and other preventive measures.

Presently, the predominant clean energy replacements for fossil fuels are solar and nuclear energies. Both are virtually inexhaustible, and neither produces greenhouse gases. The down side is the costly technology required to harness them.

A major advantage of solar energy is that it creates no acid rain, no smog, and no hazardous radiation. Low-powered energy from sunlight comes in a form that is not transportable, cannot be stored directly, and is unavailable a great deal of the time. A purely solarized world would require energy-storage capacity as there is no place where solar energy is always available. Little land would be needed to capture the needed sunlight. An area slightly larger than the state of Nevada would be sufficient to meet present day fossil fuel needs if the sunlight was utilized at only ten percent efficiency. One could easily assemble this solar energy reservoir in a desert or scrub region anywhere around the world. Arid and unproductive land with a low value for other uses could be exploited. One day solar power will be the source and a desert country the exporter.

Sunlight can be converted and stored in substances such as hydrogen, which reacts with oxygen to produce an electric current through a "fuel cell." Energy is released as a current, reacting to form water. Fuel cells are cheap to build, pollution-free, and highly efficient as devices for extracting energy from hydrogen. Although hydrogen ignites more easily than gasoline or gas, it is less dangerous in other respects. It is smokeless; its gas dissipates rapidly once released, and only hydrogen can deliver both the power density and the flexibility of fossil fuels.

Photovoltaics, wind power, biomass energy, and solar thermal generation can all play a part as well. The virtue of photovoltaic-hydrogen is that it is constructed from an endless clean energy source. Photovoltaics use direct conversion, eliminating the intermediate step of running a generator with a steam turbine. Photovoltaic cells are slivers of semiconductor mounted on metal, glass, or plastic offering simplicity and easy maintenance with few moving parts. Photovoltaics are here in commercial quantities ready to be used and will provide power at peak demand hours at optimum locations and elsewhere in the future. Two factors determine the high price of photovoltaic power: the efficiency with which a square foot of cells converts sunlight into electricity and the cost of producing that square foot. Progress will come either by improving efficiency or reducing the production costs per square foot, or both.

Wind power catches some of the sun's heat that keeps air in motion. Wind energy is one of the cheapest and cleanest renewable fuels. It's adaptable to many different uses and can be installed in short time. Thus, wind energy can easily respond to changing electrical needs. It is most economical in areas where the winds are fairly constant with speeds averaging twelve to fifteen miles per hour.

Solar and wind power have the fewest negative environmental impacts of any renewable technologies. Passive heating systems use the buildings themselves as collectors, storing heat in floors, walls, and other containers. Cooling is provided through simple mechanisms such as cross ventilation and shade. Active systems use materials like glass or aluminum as collectors. Fans or pumps carry the heat to storage systems.

We can look to the Earth for other energy alternatives. Biomass energy comes from agricultural wastes, forestry, and animals. Energy is provided through burning, fermentation, and the eventual conversion through anaerobic decay. When burned, cow dung, crop residue, and methanol distilled from wood release their stored solar energy. The CO2 that is released is at a lesser extent than fossil fuel burning. Methane from solid-waste landfills can be trapped and burned. Other sources of methane include anaerobic bacteria in rice paddies and bacteria in the digestive tracts of cattle. Earth's original natural removal process for methane is now partially blocked by carbon monoxide emissions from automobiles.

Tidal-energy dams utilize gravitational forces tying the earth, moon, and sun together. Geothermal systems tap remnant energy from the Earth's formation, extracting it from hot water, steam, or hot dry rock in the Earth's crust. It's many applications include space heating and cooling of homes, heat for industrial processes, and production of electricity. Geothermal energy is considered a renewable resource, but reservoirs can be exhausted if the rate of withdrawal is not managed with care.

Many people lack information on energy-saving options and/or cannot afford the initial cost. The contribution to replacing fossil fuels is small. Concern Inc. has produced a guidebook for the average American to help with step to take to improve his world. We can develop a comprehensive strategy, adopt a national energy policy encouraging efficiency and environmental protection, limit our use of fossil fuels, conserve energy, and use it more efficiently. We can develop and use renewable sources of energy in homes, our community, industry and transportation system. We can adopt sustainable agricultural practices, stop deforestation, demonstrate international leadership, and reduce the population explosion.

In just the past hundred years the atmospheric concentration of heat-trapping gases has risen twenty two percent. Higher CO2 levels will raise the world's average temperature up to possible eight degrees Fahrenheit. Automobiles and trucks consume more than sixty percent of the oil burned in the United States each day, adding hundreds of thousands of tons of carbon dioxide to the global greenhouse. All of that combustion, in power plants, automobiles, and factories, has transformed hundreds of billions of tons of ancient buried carbon into a great burst of carbon dioxide gas. Attempts to use alternative approaches, such as tying taxation to the costs caused by gasoline combustion, suffer from the lack of knowledge, particularly about global damage.

Perhaps the simplest steps a person can take to begin to counter the greenhouse effect is to re-establish a connection to the natural world. Start with basic act of taking a walk in the woods.