THE GOOD EARTH

Harvesting Earth's Resources

Introduction

Why should we care about the harvesting of Earth's resources? Think of your daily routine. You probably wake up to the sound of your alarm clock, flip on the light, shower, brush those pearly whites, dress, do the hair, have your morning coffee, hop in the Ferrari and zoom off to wherever the day takes you. At this point you have already used immense amounts of natural resources. None of these processes, in the way that you know them, would have been possible without the materials that the Earth provides us with. The supply of these resources has the ability to impose strict limits on society, and humanity as a whole. Will the growth of the human population be stunted by the availabilty, or lack thereof, of natural resources? Although it's not an immediate threat, our reserves are finite and depletion is inevitable. These resources did not appear overnight. A year's supply of oil for the United States alone takes Mother Nature one million years to make The time to take this into consideration is now. The way we harvest and conserve Earth's resources today has great bearing on the way we will live in the future. Now, what kinds of life-sustaining resources does Earth provide us with, anyway?

Energy is required and relied upon for all of our daily activities.

The Goods

What is a resource? Before continuing a discussion about specific resources, their availability, importance, and so forth it is important to define exactly what a resource is. Resource is a term which refers to the source in its entirety. This includes those portions which cannot now, nor ever, be extracted from the Earth for human use. On the other hand, the term reserve is used to define those portions of resources which are extractable with the technological and economical capabilites currently available. Thus, only certain portions of resources are actually reserves. No matter how much of a resource is available, it is obviously the part that is obtainable that is of use to us. Reserves, then, are our primary interest. It is our reserve supply that has the most bearing on our every day lives, and that impose limits upon us.

The Air That We Breathe: Atmospheric Oxygen

Without the atmosphere that it has, the Earth would not be capable of supporting life. It's that simple. Is there life on Mars? No. There's no atmosphere. Is there life on Jupiter? No. You just try to breathe there. Is there life on Earth? Life, yes. Intelligent, we may never know.

Our modern day atmosphere is comprised mostly of gases, primarily nitrogen (78%), and oxygen (21%), the other 1% being random gases and particles, such as carbon dioxide, water vapor, and dust. The oxygen is what's responsible for all the chemical reactions that take place on Earth, most importantly plant and animal respiration. In our atmosphere, there is a delicate balance between oxygen and carbon dioxide which is biologically maintained. The percentage of oxygen is due to the presence of plants and the process of photosynthesis, while the carbon dioxide is a product of animal respiration.

The atmosphere hasn't always been so breather-friendly. In the beginning, the primitive atmosphere contained carbon dioxide, nitrogen, and other gases. Then plants came along, and the compostion of the atmosphere changed as oxygen began to accumulate as a result of, you guessed it, photosynthesis.

At the rate we're going, the atmosphere won't always be so breather-friendly. With large-scale deforestation (discussed further in the chapter), the production of oxygen is decreased. Furthermore, within the past century, we humans have altered the chemical composition of the atmosphere by releasing large quantities of pollutants. In metropolitan Los Angeles alone, 9000 tons of smog are released daily. GASP!

They Keep Things Running: Fossil Fuels

Coal, petroleum, and natural gas constitute 95% of the world's energy needs. These three sources are called fossil fuels because they, like fossils, are preserved from past geological ages. However, these fossils aren't brachiosaurus footprints: they are ancient solar energy converted into combustible carbon-rich substances. Stored as heat from the sun in organic matter, they underwent biological processes and were then preserved and buried under the sediment of the Earth. Now, 200 million years later, we can uncover these reserves and use them to run our cars, homes, and power plants.



Fossil fuels such as coal are not only non-renewable, they also generate harmful pollutants.

And two eyes made out of... : Coal

Coal is a very desirable resource due to its abundance: its reserves remain substantially large. This, of course, is a relative term to the scarce levels of other fossil fuels. It is expected that widespread availability will continue, but only until about the year 2200- well within most of our lifetimes.

Coal deposits come from plant material that lived in prehistoric swamps found along low-lying coastal plains. The majority of coal reserves are found in the United States and The Russian Federation. However, there are many factors that make it less attractive than the other major fossil fuels. First, it is an extremely bulky solid, making extraction, transportation and distribution difficult and costly. Secondly, it isn't very versatile. Lastly, and most importantly, it is damaging to the environment. The transformation of coal into usable energy causes many ill effects, most notably air pollution resulting from sulfur and nitrogen oxide biproducts. In areas where air pollution is severe, smog alerts and acid rainstorms are common.

What a natural... : Gas (and Petroleum)

Petroleum and natural gas are related hydrocarbons often found together in geological formations. Both are excellent sources of energy with numerous positive characteristics. Each contain large concentrations of chemically converted solar energy per unit of mass. Another plus is that they are easy to handle and transport.



Pipes carrying oil will stand empty and obsolete when our reserve supply is depleted.

Petroleum is very versatile and can be changed into different forms for different purposes. It is pumped out of the ground in the form of crude oil, a gooey, dark liquid composed of many different chemical compounds. Oil refineries convert it into useful materials such as kerosene, gasoline, propane, motor oil, road tar, and plastics. The consumption of petroleum doubled from 1948 to 1970. If this pattern continues with a 100% increase every 22 years, 660 years from now we will be using the same amount of petroleum per year as there is water in the oceans.

Natural methane gas is easy to use because it can be pumped directly from the production source to the site of consumption. Present in oil wells heated above 150 degrees Celsius during burial, it floats above the heavier liquid petroleum. It can also, in some instances, be trapped in its own seperate reservoir. Since it releases virtually no pollutants when burned, natural gas is becoming more and more popular as pollution laws become stricter.




Natural gas resources and reserves for the United States



United States energy consumption 1949-1989

H₂O Plus: Water

Water covers 71% of the Earth's surface, which is evidenced by the huge amount of blue on a globe. The oceans are the prime reservoir, comprising 97% of the world's water. Of the remaining 3%, which is fresh water, the majority is frozen in the ice caps of Antarctica and Greenland. The amount of available fresh water sets limits on the population of certain areas, and on the Earth as a whole. Although it is a renewable resource, the process, as any other, takes much time. As far as we are concerned, it is in finite supply. In 1993, 26 countries with a total population of 230 million people fell into the "water-scarce" category. By 2001, estimates indicate that 11 African countries, 400 million people, will be deprived of water.

Water can be used to generate hydropower. Although this type of energy is not yet fully developed, even at full capacity, it would only be able to provide about 5 percent of the energy needed in the world. Hydropower involves the use of hydroelectric dams, which must be built on rivers. These can create many damaging side effects, causing harm to the river and its inhabitants by offsetting the balance and the flow of nature.



Water sustains life. No water, no life. We must conserve and stop contaminating this precious supply. Any questions?

This Ore That: Ores

Ore deposits are any natural material sufficiently enriched in one or more elements; usually minerals or metals. They are divided up into four groups based on their uses. The first and most valuable group is metals, such as copper, iron, and aluminum. Their products can be seen everywhere from batteries and buildings to airplanes and soda cans. The second group is industrial minerals, such as lime (a concrete binding component of cement), and ash, an alkaline used in chemical processes. The third group is construction materials, like sand, gravel, and stone. These are used primarily as concrete fillers. Fossil fuels, discussed earlier in the chapter, are the fourth class of ores, called energy minerals.

When mined, ore reserves are depleted very rapidly, for they are an unrenewable resource. There are many methods by which deposits are formed, the most common of which are hydrothermal processes and crystal settling. In hydrothermal processes, veins of minerals or metals are formed when sheet-like deposits precipitated by hot water solutions that fill fractures in the earth or deposit near igneous regions. Crystal settling occurs when mineral particles in a cooling magma chamber crystallize and sink to the bottom.

Ore extraction is a complex, and often dirty process. It is first dug up, then crushed and chemically seperated from surrounding materials. Large piles of waste rock are left and allowed to erode into water supplies, harming aquatic habitats. Mining also ruins landscapes by contributing to deforestation, air and water pollution. Such pollution endangers the lives of all populations in the environment. The growth rate of plants is slowed, causing the growth rate of the entire food chain to decrease. The people who live and work by these mining sites are plagued with lung and skin cancer as a result of harmful biproducts.

Bertle and Anaconda, Montana comprise an area of 10 square miles of mines and mills. Waste piles from these sites are an average of 50 feet in height, equivalent to that of a five story building. Toxins from these wastes have seeped 150 kilometers downstream. Partial cleanup alone is estimated to cost as much as hundreds of millions of dollars; an exhorbitant price for an exhorbitant mess.



Sources of pollution in the United States

What wood you say? : Wood

Wood was the first energy source used by people, other than food products. It served as the primary fuel source in heating homes (caves and houses), cooking and running factories until about 200 years ago. Wood has a comparatively low heat content per unit of mass and collection involves a lot of labor. Furthermore, the trees and forests around the globe, as a result of mass deforestation, are rapidly disappearing at an alarming rate of 17 million hectares per year; an area about half the size of Finland. This not only limits our ability to use wood as energy; it also takes away from our oxygen supply and natural habitat.



Our beautiful forests are disappearing at a rapid rate.

No Alternative: Where do we go from here?

So, your world is crashing down all around you. Your resources are being depleted, your atmosphere is being polluted, and you feel trapped. What shall you do? You can get yourself clean, you can have a good meal, and you can do whatever you feel at the Y-M-C-A. You can dig a hole and put your head in it. You can plan a mass exodus to the moon. Feasible, yes. Reasonable, no. Now what? There is a rapidly expanding global market for competitively priced, clean, "green" energy services that don't pollute or destroy natural resources.

What are these "green" energy services, you ask? Here's the lowdown.

Geothermal Energy

Geothermal energy is a renewable, economical heat source from deep in the Earth. Ground water is heated by magma to form hydrothermal resources, which are naturally occurring hot water and steam reservoirs. The steam from these pockets is used to run a turbine engine, which generates electricity. As of now, it is restricted to areas where we have such activity, such as Iceland. Elsewhere, this form of energy is produced at great cost: as the heated water is extracted, hollow underground pockets are left, leading to changes in pressure and eventually, a disastrous collapse. The number of hydrothermal resources will increase as better technology is developed, and if the government catches on.

Nuclear Energy

Nuclear energy is another form of economical, renewable, non-polluting energy. There are two ways of harnessing this energy. First is the process of nuclear fission, or splitting atoms. U235, an isotope of uranium, is bombarded with neutrons and splits from the impact. This division releases immense amounts of heat energy, which can be used to change water into steam, driving a steam turbine, generating electricity. Second is nuclear fusion, or merging atoms. In this process, the nuclei of light elements combine to form heavier nuclei, producing tremendous amounts of energy and doing the same as above.

A useful reactor of this kind has yet to be developed. A site in Texas was proposed, but it was deemed impractical; a huge underground area is needed for such a reactor.

Although it's "non-polluting", nuclear energy does have its negatives: radioactive waste products. Irradiated uranium fuel from commercial nuclear power plants is among the most dangerous radioactive wastes. 30 tons of this stuff is discharged annually from one reactor alone. Total waste generation from all nuclear reactors operating worldwide will exceed 450,00 tons before the middle of the next century.

Nuclear energy will gain importance as fossil fuels become more expensive and alternative energy sources are not developed, but without proper waste disposal methods, the costs far outweigh the benefits.

Solar Energy

Let there be light! Solar energy is our most important constant energy source. Clean and reliable (the Sun won't be burning out for a while), it can be used to generate heat and electricity. Solar energy is harnessed and concentrated into panels, converted into electricity, and distributed.

This process, though environmentally sound, is quite expensive. Generating 1,000 gigawatt-hours of electricity per year, for example, requires 100 workers in a nuclear power plant, but 248 in a solar thermal facility. Another con is that this renewable energy source is not suited to the 24-hour-a-day baseload operation of today's coal and nuclear plants.



Solar powererd cars like these compete in the Winston Solar Challenge race.

Biomass

Biomass is the energy obtained by using plants and plant products, such as paper, wood, and charcoal as fuel. If the use of this energy source were to increase by 50 percent in the next ten years, more than 70,000 new jobs would be created, and there would be a worldwide increase in agriculture, fabricated metal products and the retail trade; big-time economic gains.

More than half of the household trash in the United States and Canada is paper, which can be used as fuel. An electrical generator that operates solely on trash can generate 550 megawatts, enough to light the homes of more than 50,000 families annually.

Wind Power

Wind turbines use advanced technologies to produce electricity for homes, businesses, and utilities, using the same principles of hydroelectric energy (see H2O Plus).

The windmill sure has come a long way. In 1990, 13,000 wind generators produced 1000 megawatts of electricity, about the output of a large nuclear reactor. Labor costs are high for wind power; 540 workers are needed to operate a wind farm.



Wind turbines like this one in California are being tested and used as possible alternatives for energy sources.

Nature has provided us with many different resources which our society has come to rely on. This dependence has placed a strain on the environment. Our massive consumption of these resources has left us with little choice but to be more efficient in our usage so as not to waste the little we have left. With the exponential growth of the world's population and constant technological advancements, demands for energy are increasing daily.

With improved efficiency of buildings, appliances, factories, vehicles, and other energy-drainers, assessments indicate that more than a trillion dollars per decade could be saved. There would also be a substantial reduction in environmental pollution. Conservation should be our goal. As Gifford Pichot, the "Father of Conservation" said:

The first great fact about conservationism is that it stands for development...

Conservation does mean provision for the future, but it means also and first of all the recognition of the right of the present generation to the fullest necessary use of all the resources with which this [world] is abundantly blessed. Conservation demands the welfare of this generation first, and afterward the welfare of the generations to follow...

So when you wake up tomorrow morning, consider cutting the shower short, letting your hair dry naturally, even biking to wherever the day takes you. The Earth, and your kids, will thank you.

Brown, Lester R. et el. State of the World. New York: W.W. Norton, 1992.

Buttel, Frederick and Craig Humphrey. Environment, Energy & Society. Belmont: Wadsworth, 1982.

Committee on Resources and Man. Resources and Man. San Francisco: Freeman, 1969.

Ehrlich, Anne H. and Paul R. Ehrlich. Population/ Resources/ Environment. 2nd ed. San Francisco: Freeman, 1972.

Humblin, W. Kenneth. Earth's Dynamic Systems. 6th ed. New York: Macmillan, 1992.

Web Sites

http://solstice.crest.org/

http://www.nrel.gov/data/pix