Things Are Heating Up: The Threat of Global Warming
by Teresa Nelson

The verdict is in—we're getting warmer. What for years has been a debate among scientists, politicians, and large corporations has now become a fact—one that affects all of us, not just those wrangling scientists, politicians and executives of corporations. A recently released report from a United Nations-sponsored group known as the Intergovernmental Panel on Climate Change (IPCC) states that "The increase in temperature in the 20th century is likely (66-90% chance) to have been the largest of any century during the past 1,000 years" (Albritton 2). The panel consists of 2500 scientists from around the world and most of them participated in, or contributed to, the research compiled in this report. The result is an estimated average rise of just over 1°F (0.6°C) in the surface temperature of the Earth. On the surface, this change seems too small to matter, but the predictions based on this tiny rise are very dramatic and alarming.

The National Research Council, which is the United States National Academies of Science research institute, released a separate report early this year corroborating the climb in surface temperature; this council was established by the U.S. Congress to advise the government on scientific and technological issues. Serious environmental implications are being predicted if we should ignore these findings and continue down the current destructive road we're traveling. Unfortunately for the United States and the world, it appears President Bush is leading the parade down this destructive road. In 1997 world leaders from 160 countries gathered in Kyoto, Japan and signed the Kyoto Protocol, which requires "industrial nations to reduce their greenhouse emissions to an average of 5.2% below 1990 levels between the years 2008 and 2012" (Linden 55). While representatives of the United States signed the Protocol, President Bush has refused to ratify it, declaring it dead. Because of the necessity of finding and producing alternative, cleaner fuel sources and transportation, the companies most affected by these new laws and requirements would be those connected to the oil and automobile industries. Being from Texas, a state that relies heavily upon the income generated by the oil industry, President Bush is reluctant to force those industries to comply with the stringent guidelines put forth by the Kyoto Protocol. In the Time magazine article, "A Climate of Despair," Jeffrey Kluger asserts that the United States is the largest contributor of air pollutants in the world; even though just four percent of the world population resides in the U.S., we produce twenty-five percent of the air pollutants (30). With that amount of responsibility toward fueling the polluted condition the world is now in, the other countries that agreed with Kyoto feel moving forward without the United States would be futile—and grossly unjust. Cleaning the air of its pollutants and changing industries to prevent or reduce the amount of pollutants expelled into the atmosphere will be costly. The United States is the richest country in the world—and the heaviest polluter—yet chooses not to participate in the cleanup. In President Bush's defense, it appears he is trying to control expenses. In addition to the cleanup and retooling expenses, a billion-dollar fund is to be established by 2005 to help developing countries limit their emissions, a cost to the U.S. of about 250 million dollars ("New Climate"). Consequently, the wrangling has now shifted from the debate over whether global warming exists to become a debate over who is most responsible and liable for the cleanup and prevention expenses.

Meanwhile, as the politicians continue their posturing, politicking, and procrastinating, the fact remains that the world is heating up and there will be dire consequences to face if this climb in temperature is not curbed soon. These consequences will not only be faced by us, but by the people who will be paying most heavily: our children, grandchildren, and the generations to follow—as well as all inhabitants of all ecological systems. The predictions are made for the next 100 years, and they range in seriousness from drought which will cause fires, famine, and a sharp rise in heat-related deaths, to severe flooding with entire islands and coastal lowland areas disappearing, resulting in all the inhabitants fleeing their homes and becoming environmental refugees. Global warming is a fact, endorsed by a majority of scientists around the world; the industrial and technical progress of the human population has played a major role in the acceleration of the destruction of our atmosphere. Because of the serious effect this will have on all the Earth's living species, we, as good stewards of the Earth and being accountable for our actions, are responsible for curbing this destructive trend and for doing all within our power to rectify the current dangerous situation.

Just what is Global Warming?

The weather is always a safe topic of conversation, discussed daily as a means of interacting with friends, acquaintances, and sometimes strangers. Even though we watch changes in the weather from day to day, rarely do we actually recognize major alterations in weather patterns. We don't notice those patterns until we step back and look at the larger picture, comparing current seasons with those we've experienced in the past. Even then, only by taking scientific measurements over very long periods of time can anyone begin to determine major changes in weather patterns, eventually leading to analyses of shifts in global conditions and predictions of possible consequences.

Instrumental records of temperatures have been compiled since 1861. In analyzing these records, as well as data taken from ice core readings and other recorded observations through the centuries, the IPCC concludes, "Concentrations of atmospheric greenhouse gases and their radiative forcing have continued to increase as a result of human activities" (Albritton 7). Greenhouse gases are always present in our atmosphere and create what is commonly known as the Greenhouse Effect. In his book, Global Warming, Andrew Revkin tells of the French mathematician, Jean-Baptiste-Joseph Fourier, who in 1827 first compared the Earth to a "glass vessel." Fourier made the observation that the air around the Earth lets in sunlight without allowing all the resulting warmth to escape from the atmosphere, thereby keeping us cozy. The basic physics are summed up very succinctly by Revkin:

Most of the sun's energy travels to Earth as visible light. The sunlight enters the atmosphere and warms things up—particularly things that are dark in color and thus absorb a lot of light, things such as plants, soil, and the oceans. Surfaces warmed by the sun then begin to shed that accumulated energy. The greenhouse gases act like an insulating blanket. Without the greenhouse effect, heat energy would quickly radiate back into space from the Earth's surface, leaving the planet with a temperature close to 0°F (-18°C), instead of the present comfortable average of 59°F (15°C). (63-66)

This aptly describes conditions in a greenhouse where sunlight is transformed into heat as it passes through the glass panels of the house, and is then trapped inside by those very same glass panels to be absorbed by the interior contents of the greenhouse. Revkin equates these panels of glass in the greenhouse effect scenario to certain gases present in the atmosphere; even though nearly 99% of the atmosphere consists of oxygen and nitrogen, gases which have no heat-trapping abilities, the trace gases which insulate our planet are extremely efficient in doing so, and therefore are susceptible to minor variances in the amounts present (62-63). These variations in concentrations of the trace gases in turn produce serious consequences in ecosystems on Earth.

The gases responsible for our insulation include carbon dioxide, methane, nitrous oxide, and a recent man-made addition, chlorofluorocarbons. Carbon dioxide (CO2) is the most serious greenhouse gas because of its abundance in the atmosphere and the rate at which it is growing in concentration. Beginning as early as the mid-1700s, the time of the American Revolution, changes in lifestyles began as the world headed toward the Industrial Revolution. Forests in Europe fell and became fuel as man discovered new uses for heat in the production of necessities such as cloth and tools (71). In addition to using wood as fuel, Gale E. Christianson notes in his historical account of global warming, Greenhouse, that the major source of heat in European households was charcoal.

The charcoal was prepared by piling wood into stacks, covering it with earth or turf, then setting it afire. During combustion, the volatile compounds in the wood pass off as vapors while the remaining carbon is converted into charcoal. By weight, charcoal gives more heat than wood. (42)

Wood eventually became scarce near cities and very expensive to transport from the country; as a result, alternative sources of fuel were sought, and eventually coal replaced the use of wood (43). With fewer trees to filter the CO2 from the air, the concentration began to increase. As coal replaced wood and combustion engines were invented to increase productivity, even more CO2 was deposited into the atmosphere, and at a faster rate than ever before. By 1900, "The concentration of CO2 in the atmosphere was already approaching 300 parts per million and steadily rising" (Revkin 71-72). Today the concentration of CO2 in our atmosphere is more than 360 parts per million (ppm) and has increased about 1.5 ppm per year for the last twenty years. Consequently, according to today's scientific calculations, "About three-quarters of the…emissions of CO2 to the atmosphere during the past 20 years is due to fossil fuel burning. The rest is predominantly due to land-use change, especially deforestation" (Albritton 7). As rain forests fall, so too does nature's ability to filter CO2 from the atmosphere and replace it with precious oxygen.

A second very serious culprit gas in the global warming scenario is a class of chlorofluorocarbons or CFC's. They are man-made gases and were invented by Thomas Midgely, Jr., in 1930, the same inventor who discovered that adding lead (another air pollutant) to gasoline eliminated the knocking in automobile engines. Working for General Motors' Frigidaire division as a chemist, Midgely was assigned the task of finding a replacement for the ammonia and sulphur dioxide, very toxic chemicals which circulated in the coils of refrigeration units. He invented freon, which, at that time, was thought to be "a purely synthetic substance that lasted for centuries and had no known adverse effects" (98). Today, freon is used as a refrigerant in air conditioners around the world; cars, homes, apartment complexes, office buildings, shopping centers, and large hotels all contribute to the greenhouse effect worldwide when chlorofluorocarbons are released into the atmosphere as air conditioners maintain consistently cool temperatures. Not only do CFC's take part in exacerbating the greenhouse conditions; they are the same substances which attack the Earth's protective ozone layer in the stratosphere, and have created a hole which now allows the sun's dangerous ultraviolet rays to enter our atmosphere, causing damage to plant and animal species. "Although CFCs exist in the atmosphere in minute levels—measured in parts per trillion—each molecule has more than 12,000 times the heat-trapping potential of a molecule of carbon dioxide" (99). There has been a curbing of the use and production of CFC's since 1970 due to legislation that restricts the manufacturing and selling of products containing these gases; however, there is still a growth of five percent of the amount released into the air each year.

Methane and nitrous oxide are two additional primary greenhouse gases responsible for causing a rise in the Earth's temperature; however, they aren't as prevalent as carbon dioxide, nor as destructive and long-lasting as chlorofluorocarbons. Nitrous oxide is created by soil microbes and seeps from the earth into the atmosphere; the addition of nitrate fertilizers to farmlands and the practice of tilling the soil accelerate the cycle of the creation and release of the gas. Methane, also known as natural gas or swamp gas, is 20-30 times more efficient at trapping heat than carbon dioxide. It's found in peat bogs, rice paddies, landfills, and, surprisingly, in the guts of cattle. This gas helps break down the food taken into the cows' stomachs; but in the process, each cow belches methane into the atmosphere about twice a minute. As the human population has grown, so too has the livestock population. In addition, scientists are realizing that a cycle is developing from global warming in which more methane is being released as permafrost thaws; normally the gas lies trapped in the frozen ground, but those areas are showing signs of thawing, allowing the trapped methane to escape (Revkin 95).

Even though we can't see or smell them, the increase of these greenhouse gases has serious consequences for all inhabitants of Earth. We are now beginning to feel and see the results, and because of this we must find ways of counteracting the effects and controlling the amounts of gases we knowingly emit into the atmosphere.

The Heat is On!

The IPCC has stated that the 1990s was the warmest decade since 1861 when records were first kept, with 1998 the hottest year (Albritton 2). Before that, 1997 had been the warmest year on record, but the summer of 1988 was most memorable to many. The hole in the ozone layer had been discovered three years earlier, prompting an agreement known as the Montreal Protocol in September of 1987. By the following June, temperatures were soaring, raising havoc across the United States. The Midwest suffered through the worst drought since the 1930s dust bowl conditions with yields of crops reduced thirty to forty percent. In Los Angeles 400 electrical transformers exploded in one day due to the strain of cooling the residents from the 110° heat. While we suffered through unending heat waves, tropical areas of the world were enduring catastrophic flooding, causing refugee situations, which in turn resulted in epidemics of cholera and dysentery. "Nationwide, 2,000 daily temperature records were set, while an estimated 10,000 ‘excess' deaths were linked to heat stress" (Christianson 196-97). These unusual conditions resemble very closely the predictions being made for the next century with the advent and acceleration of global warming.

Although 1°F (0.6°C) appears to be a minor rise in temperature, there is evidence that a shift of merely nine degrees ended the last Ice Age (Lemonick, "Life" 26). The Earth has fluctuated for millions of years between ice ages and extreme warming trends, but this is the first major shift in which humankind is involved—not just as an observer or an innocent bystander, but as a catalyst. The IPCC has determined that humans are contributing to the greenhouse effect by adding pollutants to the air through the combustion of fossil fuels (Albritton 2). Carl Sagan, the late astronomer and biologist, describes in his book, Billions and Billions, just how fossil fuels were made by nature:

Three hundred million years ago the Earth was covered by vast swamps. When the ferns, horsetails and club mosses died, they were buried in muck. Ages passed; the remains were carried down underground and there transformed by slow stages into a hard organic solid that we call coal. In other locales and epochs, immense numbers of one-celled plants and animals died, sank to the sea floor, and were covered by sediment. Simmering for ages, their remains were…converted to buried organic liquids that we call petroleum and natural gas. (117)

In addition to retrieving and burning those fossil fuels, humans are introducing other greenhouse gases into the atmosphere as a result of their daily activities. Through efforts of scientists around the world, the measurements, especially in the Northern Hemisphere indicate a rise in surface temperature, not only of maximum temperatures, but also of minimum temperatures (Albritton 2). These warmer minimum temperatures are causing less freezing and shorter freeze seasons, resulting in less snow pack in areas, glacier reduction, and longer growing seasons. While these longer growing seasons sound like a benefit, without the snow pack to feed irrigation supplies, there is not enough water to sustain the crops through their harvest. In addition, with a longer season, the plants flower and produce fruit earlier, disrupting the cycles of pollinating species which depend upon them as a food source; if the birds and bees have not emerged or migrated back to the area, pollination of the crops is limited, resulting in less fruit, vegetables, and grains.

The ecological balance is upset by the longer seasons, causing stress to species, possibly leading to extinction. In a ten-year study, scientists have determined a link between the decline in 200 species of amphibians, about twenty of which have gone extinct, and global warming. El Niño's warming cycles and the decrease in the snow and rain in Oregon's Cascade Mountains have caused a lack of water in the last ten years, which stresses the embryos, increasing the mortality rate from a normal twelve percent to a dangerous eighty percent. Joseph Kiesecker, lead author of the study states, "Altered precipitation patterns resulted in lower levels of water in ponds and lakes, where amphibians lay their eggs. Around the early 1990s, we started to see 80 to 100 percent mortality" (qtd. in Higgins). Without the balance that now exists in nature, many species must adapt to survive. Many plants rely upon freezing temperatures for specific lengths of time during the winter to encourage germination and growth in the spring. Without these freezing temperatures, the plants suffer stunted growth, reducing their production of food supplies.

Two studies, one done using satellite data and one using earthbound data, have established that growing seasons have recently lengthened. The first study was conducted by Ranga Myneni of Boston University; the results indicated that between 1981 and 1991, spring began eight days earlier and fall ended four days later than in previous decades. Annette Menzel and Peter Fabian of the University of Munich determined through their analysis of spring and fall events that the European growing season lengthened by eleven days between 1959 and 1993. As a consequence of these longer warm periods, some species of birds are laying eggs earlier, sometimes in response to earlier leafing of plants which, in turn, can cause insects to emerge earlier (Pavelitz). Simply stated, the lengthening of the growing season is warmer weather for longer periods and freezing weather for shorter periods.

The adaptability of species when their ecosystems become warmer than normal is the concern of scientists and researchers throughout the world. The executive summary of the Pew Center's report, "Ecosystems & Global Climate Change," expresses concern for the adaptations required of species in changing ecosystems due to the predicted 1°-4°C (1.8°-7.2°F) rise in temperature in this century.

Species have shifted their distributions in the past in response to changing climates; however, estimates of the rate of warming suggest that it may occur relatively quickly, some 10 times faster than the warming at the end of the recent glacial maximum…It is likely that some species will be unable to move at these high rates and hence may gradually die out as climate conditions become increasingly unsuitable. The more rapid the rate of climate change, the greater the potential for this filtering effect. (Ecosystems)

While most animal species have the mobility to move freely from one habitat to another, plants and trees do not relocate as easily. As the habitats warm, the general trend is to move northward to cooler areas; but trees cannot climb mountains, nor can they easily disperse their seeds farther up the mountain side. While the temperature on a mountain is one factor determining the location of the timberline, it isn't the only factor; in the higher areas, the soil is usually less fertile and rockier, with steeper inclines, making the establishment and survival of trees precarious at best. The U.S. Environmental Protection Agency predicts that forests could shift by 200 miles northward if the projected 2°C (3.6°F) rise in temperature becomes fact. If the temperature climb is slow, the northern edges of the forests would become warm enough for the trees as the southern edges became too inhospitable to support them. But, even at the projected rate, the forest species would need to migrate two miles every year ("Global Warming"). Because of the current rise in temperature of the Earth's surface, species already show signs of adapting, as in the case of the birds, and of going extinct, as in the case of the amphibians; and without any curbing of greenhouse gas production, there is little doubt that it will get even warmer, causing further adaptations and extinctions.

The disease-bearing insects, known as vector insects, are expected not just to adapt, but to flourish in the warmer temperatures; they are, in fact, expected to migrate farther north than their current habitats in equatorial and subequatorial climates. Since 1990, the hottest decade on record, the incidence of locally-transmitted malaria, carried by mosquitos, has increased across the U.S.; until then, through the efforts of national mosquito control programs, malaria was restricted to a few cases annually in California. This disease has also returned to southern Europe, Korea, and the former Soviet Union. Dr. Paul Epstein, associate director of the Center for Health and the Global Environment at Harvard medical School states, "Some [computer] models project that by the end of the 21st century, ongoing warming will have enlarged the zone of potential malaria transmission from an area containing 45 percent of the world's population to an area containing about 60 percent" (Epstein). The World Health Organization estimates the number of people currently suffering with malaria to be between 300 and 500 million; two million, mostly children, die as a result of this disease each year (Christianson 240).

In addition to vector-borne diseases, waterborne diseases are a further concern to scientists and health organizations. Flooding contaminates drinking water, causing illness in those who are exposed to the bacteria and parasites, either by ingesting them directly or through poisoned fish and shellfish. Droughts deplete water supplies and concentrate contaminants that otherwise would be diluted in larger bodies of water; clean water is crucial to health in normal conditions, but especially so in stressful conditions caused by flooding or drought. With vigilance and health programs in place to handle outbreaks of diseases normally found in warmer climates, the outcome might be controllable. However, with the ability to travel across the world in a matter of hours, parasites, insects, and bacteria are easily spread. Technologically advanced societies will be able to respond quickly to combat outbreaks, but what about poorer, third-world countries? They are currently unable to provide adequate medical help in the form of nursing, vaccinations, and medicine for populations already suffering with numerous illnesses; they will be hard-pressed to handle further outbreaks of diseases—some of which they have never before encountered.

Glaciers are Melting, Icebergs are Calving, and the Seas are Rising

As the world has been heating, the glaciers have been retreating. Once again, the IPCC reports, "There has been a widespread retreat of mountain glaciers in nonpolar regions during the 20th century" (Albritton 4). Glaciologist Keith Echelmeyer has spent the last eight years assessing the health of approximately ninety glaciers from northern Alaska down into the Cascade Mountains in Washington. To remain healthy, a glacier must accumulate at least the same amount of snow in winter months that it loses during the warm summer months. But, according to Echelmeyer's data, ninety percent of the glaciers he studies are losing more surface bulk than they're gaining each year; at this point, this data points to warmer temperatures as one important reason for the glaciers' decline (Monasterksy 31). Elsewhere on Earth, other countries are experiencing reduction of glacier mass as well. "Scientists agree that because of steadily rising global temperatures more than half the ice in alpine glaciers has melted since 1850 and 100 glaciers have disappeared altogether" (Lynas). In Europe's case, as the Alps have lost their glaciers, Europeans have lost revenue because of shorter skiing seasons, forcing residents of alpine villages to reassess their economic situations. In addition, with thawing comes further danger in the form of landslides. Permafrost has held boulders and earth in place for centuries; once the glaciers are gone, the permafrost thaws, loosening the rocks, boulders and debris (Lynas). As the glaciers retreat, the alpine species are advancing in their place. Where once was just ice and snow, flowers, trees, rodents, and insects are beginning to appear, building new habitats in these recently opened areas. When the trees and alpine species have nowhere to climb to escape the heat, we can hope they'll evolve or adapt to the warmer temperatures.

While mountain glaciers contain six percent of the world's ice, the Greenland and Antarctica ice sheets contain ninety percent of the world's freshwater supply; the possibility of those vast sheets of ice melting and filling the seas with fresh water has researchers concerned. It has been suggested that global warming is playing an important role in the reduction of two Antarctic ice shelves, causing ice to break off or calve and drift in the ocean. Within the past fifty years, the Antarctic temperatures have increased by about 4.5°C (39°F), causing a total loss of ice mass of about 7,000 square kilometers from the two shelves within that time period. In 1998 alone, a total of 3,000 square kilometers was lost from the ice shelves surrounding Antarctica. Says David Vaughn, a researcher with the Ice and Climate Division of the British Antarctic Survey, "Within a few years, much of the Wilkins ice shelf will likely be gone" (qtd in Hall).

On the opposite side of the world, polar ice is disappearing. Analysis from submarines' sonar data ice depth measurements throughout the Arctic Ocean from the late 1950s indicates a consistent decline in the thickness of sea ice of more than forty percent. Harvard oceanographer James McCarthy and paleontologist for the American Museum of Natural History Malcolm McKenna traveled on a Russian ice breaker last summer to the North Pole to view the ice; however, substantially less ice was found than in previous summers. Instead of the traditional pounding of thick ice sheets hitting the hull of the ship, they experienced gentle cruising through water and thin sheets of ice as they reached the North Pole, located in a large pool of water (McCarthy). It was a shock reported around the world and became known as the "polar ice pack that wasn't there" (Hudson 60). Not only at the North Pole itself, but also throughout the entire region, McCarthy and McKenna encountered very thin and sparse ice. The authors speculate on the role global warming has played in these conditions:

All scenarios for future climate indicate that warming from increasing concentrations of greenhouse gases will inexorably lead to reduced summer ice in the Arctic Ocean…Loss of ice at the North Pole is symbolic—like the loss of a signature species in a particular region—of profound change in the order of nature…What else is at risk in this system? (McCarthy)

Of course, all species that live in the Arctic are at risk simply because, as is true everywhere on Earth, nothing lives in isolation—all species are interdependent. In addition, because melting ice and glaciers feed rising seas, humans around the entire world are affected, or soon will be.

Indeed, the latest reports indicate the seas are rising—by approximately two millimeters a year over the past few decades. Along with melting ice, increasing temperatures of the water also contribute to the rising oceans; as the water warms, it increases in volume, a process known as thermal expansion. Further complicating the situation is the inability to accurately measure the oceans' depths. Plate tectonics, the moving and colliding of the plates in the Earth's crust, contribute to the difficulty of measuring the oceans' depths as they buckle and shift. In addition, land masses are still in the process of post glacial rebound—the land is springing upward after being released from the crush from the most recent ice age's massive glaciers. As a result of all this shifting and moving, it appears the water is rising in some areas due to plate tectonics and falling in others where post glacial rebound is occurring. Even though there is constant movement of the earth, geophysicists can calculate these changes in land mass and are able to compute approximate measurements of tidal change, in this case the rise of two millimeters per year (Schneider).

The U.S. Environmental Protection Agency states, "Sea level is rising more rapidly along the U.S. coast than worldwide. Studies by EPA and others have estimated that along the Gulf and Atlantic coasts, a one foot (30cm) rise in sea level is likely by 2050 and could occur as soon as 2025" ("Global Warming"). In the past century the total rise in sea level is nine inches worldwide; at this point in time, forty-six million people live in areas that are prone to flooding during storms (Shute 48). As the sea level rises, additional people are at risk, as land masses disappear under encroaching waters, taking homes along with them. Islands and third-world coastal countries are especially vulnerable to the threat of flooding, resulting in the elimination of clean water supplies and sanitary conditions, and enabling diseases to proliferate. Thermal expansion, melting ice and snow from glaciers and ice shelves, and unusual amounts of precipitation caused by warmer temperatures are current factors in the rising sea level and recent flooding conditions in lower-lying areas around the world.

As the sea level rises, dry lands will be destroyed when the water pushes beyond its normal limits. In the U.S., cities such as Boston, New York, Miami, New Orleans, and parts of Texas and California are extremely vulnerable because of their locations in low, flood-prone areas. "Including both the wetlands and dry land that would be lost to the sea, a two foot rise in sea level would eliminate approximately 10,000 square miles of land, an area equal to the combined size of Massachusetts and Delaware" ("Global Warming"). The rise in sea level caused by melting ice and increased precipitation is expected to cause hazardous conditions such as the destruction of wetlands, the erosion of beaches, the demolition of homes within reach of the water, and the increase of salinity of rivers and ground water.

The flip side of flooding is prolonged drought—a condition being predicted for temperate areas. "By 2015, three billion people will be living in areas without enough water" (Shute 50). Desert areas will increase in size as the drying expands those locations; downriver settlements will be the last to receive precious water, if there is any left after upriver cities and towns have pulled their share from the rivers. It is predicted that wars could erupt in the Middle East where water is an extremely precious commodity in those arid countries (50). Drying conditions are often accompanied by wildfires; last year alone saw seven million acres burned in the western United States at a cost of $1.65 billion (48). There is no doubt, drying conditions will change much of our world. Food crops will be a crucial factor in ensuring survival of people across the planet—and irrigating crops in a dry world will be a challenge. Predictions indicate that droughts will indeed be one more disaster for us to contend with; perhaps if plants cannot adapt to the warmer, drier temperatures, we can adapt to new food crops.

Heating the Greenhouse or Cooling a Continent?

Until recent years, there was doubt that the ocean temperatures were actually rising; the water pulls the heat from the air and the currents carry it through their systems, making it difficult to measure temperature fluctuations. Sidney Levitus of the National Oceanographic Data Center explains that the heat stored in ocean waters eventually returns to the atmosphere and, though delayed, this heat contributes to the greenhouse effect. "The oceans really are the memory of Earth's climate" (qtd in Simpson). The warmer water temperatures are affecting ocean species; one such victim is coral, suffering a deadly condition known as coral bleaching. The structure of coral consists of numerous tiny animals or polyps living together in large colonies; coral is normally pink, green, or golden brown because of algae living within the cylinder of each tiny polyp—along with other creatures that depend upon the coral for their existence. But in areas of the Caribbean and along the coasts of Central and South American countries, the coral is turning a dazzling white—the lethal result of warming ocean temperatures. When the water temperature rises above 32°C (89°F), the algae disappear, leaving the bleached skeleton of dead coral behind (Christianson 213-14). As the temperatures of land and air rise, so, too, does the temperature of the oceans. In 1998, El Niño, a cyclic weather phenomenon which produced warming seas, spiked the ocean's temperature, causing a global outbreak of coral bleaching. "The U.S. State Department's Coral Reef Task Force reported that the unprecedented 1998 global bleachings were a direct result of climate change caused by the burning of fossil fuels" (Helvarg). Coral bleaching is also occurring along the Great Barrier Reef near Australia, causing scientists, researchers, and environmentalists to be further concerned for the safety and preservation of coral species around the world.

A further dilemma in global warming is caused by a circulation process within oceans known as a convection current. The Sea of Japan is currently experiencing a slowing of the current within its depths.

In winter, oxygen-rich surface water in the Sea of Japan becomes colder than the water below and sinks, taking oxygen with it. The oxygen encourages the growth of bacteria that break down organic matter falling to the sea bed. At the same time, the current brings inorganic matter up from the depths, which plant plankton feed on. (Hadfield)

When first measured in the 1930s, the effects of this current reached a depth of more than 2,500 meters; today, warmer winter surface temperatures have weakened the convection current to the point that it reaches a depth of just a few hundred meters. Depriving the lower depths of oxygen will choke the life out of the plankton—the foundation of the oceans' food chain—which will, in turn, lead to the starvation and elimination of species higher on the chain (Hadfield). An additional consequence of stalled convection currents is further warming of the oceans' surface temperatures, causing accelerating the greenhouse effect. Scientists at Scripps Institution of Oceanography at the University of California, San Diego, report evidence that tides within the ocean drive changes in climate by bringing cold water to the surface through vertical mixing, thereby cooling the atmosphere. "Weak tides lead to less cold water mixing and result in warmer periods on Earth" ("New Research").

While in some cases the lack of vertical mixing is expected to lead to further warming, there are also predictions of a possible ice age in Europe due to the slowing or stopping of another convection current—one on the other side of the globe. The North Atlantic Drift brings warm surface water from the Gulf of Mexico northward to Europe and sends the cooler deep water back. Because of freshwater entering the Arctic Ocean from melting ice, the salt content is diluted (Edwards). As a result of this dilution, "Major ocean currents like the Gulf Stream could slow or even stop and so would their warming effects on northern regions . . . Global warming could, paradoxically, throw the planet into another ice age" (Lemonick, "Life" 29). Fresh water is lighter and less dense, therefore it does not sink, but instead stays on the surface, interrupting the vertical circulation of the current. The pull created by this sinking of colder water is slowing and could stop the warm Gulf water from reaching northern areas such as western Europe (Linden 56).

It has happened before. Roughly 12,000 years ago, at the end of the last Ice Age, a natural warming sent freshwater from melting glaciers flowing out of the St. Lawrence River into the North Atlantic, all but shutting down the Gulf Stream and plunging Europe into a 1,300 year deep freeze…Scientists fear that the rapid melting of sea ice could cause the same catastrophe again. (56)

Pennsylvania State University geophysicist Richard Alley fears the effects this time would be much greater with lower northern temperatures and, because colder air is dryer air, there would be more extensive droughts, both in severity and length, than any in recorded history. Although careful not to claim it would be the end of humanity, he readily agrees it would be extremely uncomfortable for us. Another scientist, Yale archaeologist Harvey Weiss, has studied the effects of climate in human history and states that it is changes in precipitation, not temperature, that cause civilizations to suffer (56). It seems a paradox that an increase in temperatures could be the cause of an ice age, but we've only to look to history to realize it can happen. Bleached and dead coral is the first warning sign that something is amiss in the oceans of the world; the possibility of losing plankton, the base of the underwater food chain, should be considered a second warning—enough to force us to review our practices before that food chain actually begins to disappear.

The Falling Forests

Even before the Industrial Revolution in the 1800s, humankind has been very cavalier about trees, considering them to be a valuable asset in nearly every situation. But we have been razing the land of its forests at an alarming rate. Old growth timber has become endangered because of the needs of big businesses. And rain forests are the latest victims. Gale Christianson neatly describes a rain forest in his book, Greenhouse, allowing us to visualize the beauty and complexity, along with the significant importance of these endangered areas.

Paradoxically, these massive ecosystems exist in what biologists term "wet deserts." Swathed in clouds of their own making, which limit the number of sunshine hours to between four and six per day, the many-layered trees prevent more than half of all the rainfall from ever reaching the forest floor. That which does falls on extremely poor soil whose few nutrients are quickly washed away into the streams and rivers in the valley floors. In evolutionary response, the dense root systems of the trees are concentrated in the uppermost soil layers, where they feed on the remaining 0.1 percent of the nutrients released by decomposing matter…Yet a typical swath of forest measuring four miles square contains a staggering number of individual species: 1,500 flowering plants, 750 trees, 125 mammals, 150 butterflies, 100 reptiles, 60 amphibians, and an estimated 50,000 different insects, most of which hatch, mature, reproduce, and live out their brief lives in the canopy overhead. (187)

Tropical rain forests are found in India, Thailand, Laos, Nepal, Sri Lanka, the Philippines, Vietnam, and of course, the Amazonian countries in South America. The deforestation in Brazil is done to make way for ranchers; the forest is burned, releasing more carbon dioxide into the atmosphere, not only through the burning process, but also by removing forever a natural vehicle for cleaning the air.

Whether logging trees from northwest areas of the United States to be cut into lumber or burning tropical forests to make room for farmers and ranchers, the destruction of these carbon sinks is dangerous for all of us in the long-term. A carbon sink is an area on Earth that absorbs and stores carbon dioxide, cleaning the air in the process. Oceans are carbon sinks, cycling the carbon that falls from the air down to the ocean floor. Because trees pull carbon from the air, they are considered carbon sinks as well. Christianson also writes of a remote area of Tasmania in which an ancient stand of Huon pines have been discovered; they are showing signs of accelerated growth because of the increase of CO2 in the atmosphere. He states that the predictions of CO2 fostering plant growth "May, in fact, be stimulating the replication of Earth's biomass. This is good news when one considers that locked inside the branches, trunk, and leaves of the average tree is a ton of CO2" (215). Perhaps other species of trees on this planet don't live the 700 years that Huon pines are known to survive, but all trees gather and store carbon, improving the quality of our world simply by living.

These current shifting conditions in land, seas, and ecosystems are just the beginning of the consequences of global warming; even though the human circumstances which contribute to global warming began near the middle of the last century, we are only now seeing actual consequences of this process other than simply the amount of particles in the atmosphere. It is small irony that the advances of mankind which began this warming process have resulted in technology that can predict the future of global warming conditions—computers.

Are We Heading for a Meltdown?

Although the Earth's temperatures have fluctuated throughout history—ancient and recent—neither previous warming periods nor ice ages were ever caused by humans' abilities to harness its energy. Michael D. Lemonick of Time magazine explains in the article "Life in the Greenhouse" how the IPCC uses elaborate computer programs to produce models that simulate present and future conditions on Earth due to global warming:

IPCC scientists fed a wide range of scenarios involving varying estimates of population and economic growth, changes in technology and other factors into computers. That process gave them about 35 estimates, ranging from 6 billion to 35 billion tons, of how much excess carbon dioxide will enter the atmosphere. Then they loaded those estimates into the even larger more powerful computer programs that attempt to model the planet's climate. Because no one climate model is considered definitive, they used seven different versions, which yielded 235 independent predictions of global temperature increase. That's where the range of 2.5°F to 10.4°F (1.4°C to 5.8°C) comes from. (27)

Although computer models have been criticized in the past for providing incomplete data to do adequate simulations, technology has advanced sufficiently to enable scientists to factor in all the greenhouse gases' abilities to trap heat, the effect of volcanic dust from eruptions and other emissions, and the variations in the sun's energy (28). Because of their ability to so accurately simulate climates around the world, the predictions of risks and hazardous conditions these latest programs have brought forth now have the world's attention.

However, there is still one scenario even computers have difficulty simulating—the effect clouds will have on the warming trend. As the temperatures increase, more clouds will be formed through accelerated evaporation from ocean waters. Billowy cumulous clouds actually reflect heat back into space, not allowing it to reach the planet, thereby keeping us cool; however, high, wispy cirrus clouds allow the sun's energy to enter the atmosphere, but then trap it there, bouncing the heat back to Earth. It's difficult to predict which type of cloud will be produced through the evaporation process (Lemonick, "Life" 28). In addition to that uncertainty, there is the debate over whether warmer temperatures will form more clouds covering the polar caps, causing an increase in snowfall. With the modest rise in temperature at this point, there has not been an increase in precipitation; in fact, most recent reports are of melting ice and calving glaciers, rather than additional snow.

Regardless of the presence of greenhouse gases, the Earth absorbs a consistent amount of energy from the sun and reflects a consistent amount back into space; however, it's the efficiency of those greenhouse gases that has trapped more heat in our atmosphere and increased the surface temperatures. More evaporation occurs as the temperature rises, causing more precipitation. But precipitation will not increase consistently across the globe; the rate of evaporation and the atmospheric circulations will determine the distribution of the precipitation. Water from the ground level evaporates, and is moved across the planet to be dispersed elsewhere. Because of the climatic changes on the Earth's surface, the weather patterns that move the precipitation will also change. It is predicted that southern areas will become drier while northern areas will become wetter. "In addition, not only will a warmer world be likely to have more precipitation, but the average precipitation event is likely to be heavier" (Karl). Computer models have given us a glimpse into the future, and because of this, we now have information which can help us survive future catastrophes caused by the warming temperatures. It is important to differentiate between impending disaster and that which will take 100 years, however—and to remember that these predictions are based on the facts as we know them to be at this moment in time. This information is invaluable for allowing us not only to be prepared for an uncertain future, but also to begin stopping the causes of these conditions.

A Silver Lining?

Although the computer models that have enabled the scientists and researchers to make these predictions about wilder weather, disappearing species, migrating plants, animals and insects, flooding, drought, and devastating diseases are not perfect, they are the best we've got—and most of the resulting scenarios are unfavorable. However, they do predict a few positive results from global warming. One such result is an increase in plant growth due to the added carbon dioxide in the atmosphere. Plants depend upon the CO2 for their energy, generating nitrogen in the process of turning the carbon dioxide into oxygen; they would respond to increased amounts of CO2 by growing faster. Combined with the longer growing seasons predicted for northern climates, this is good news (Christianson 251-52). According to the subsection titled "Agriculture & Global Climate Change" in the report generated by the Pew Center for Global Climate Change,

Temperature increases can have both positive and negative effects on crop yields, with the difference depending in part on location and on the magnitude of the increase…Evidence also suggests positive crop yield effects for mild to moderate temperature increases such as 2°C to 3°C (3.6°F to 5.4°F). However, once average global temperatures rise beyond about 4°C (7.2°F), yields begin to fall. ("Pew")

As stated before, warmer weather brings with it new insects to northern climates, possibly causing crop infestation unseen in those areas before. Because semi-arid areas are predicted to become drier and wet areas are predicted to experience increased rainfall—and all are predicted to experience more extreme climatic events—agriculture around the world will undergo many difficulties, challenges, and changes.

Inasmuch as the effects of clouds are difficult to predict with current models, one proposed outcome could be considered positive in the midst of all the negative scenarios. A rise in warmth means an increase in evaporation, which leads to more clouds and more rainfall; at the extreme northern and southern regions of the planet, the result would be more snowfall. Bright, white snow reflects heat before it can be absorbed into the Earth, possibly reducing the acceleration of global warming in those areas. More thick, moisture-bearing clouds would also help reduce the amount of sunlight reaching the Earth, thereby reducing the amount of heat in the air (Lemonick, "Life" 28).

As with many things in this world, one side benefit of warmer temperatures will be gained at a substantial cost. The number of people who die as a result of cold temperatures and freezing weather will decrease. Today, approximately 1,000 lives are claimed each year in the United States due to cold weather conditions. "However, the EPA reports that for every individual death attributable to cold, two others will die because of exposure to high temperatures" (Christianson 251). Warm climates are more heavily populated than cold climates, and often by populations with fewer medical facilities available to help alleviate the hardships caused by extreme heat. This benefit is actually a double-edged sword, causing more harm in the long-term than advantages.

Science is still working diligently to refine the models so that we all may be better prepared for the coming consequences—positive and negative. If there is a silver lining to the issue of global warming, it is very thin. While increased plant growth will help filter more CO2 from the atmosphere, it is likely to be too little, too late. An increase in clouds and a decrease in deaths from cold conditions both come at a cost: more rain for already flooding areas and more deaths from the effects of increased heat. In considering the numerous disadvantages of global warming, these positive effects are extremely expensive, with the cost being tallied in human lives and endangered species.

The Nonbelievers

Very few claims to dispute this predicted warming trend or to discredit the data that substantiates it are being made by scientists. However, there are a few outspoken researchers claiming the situation is not as serious as the public is being led to believe. One such person is John Christy, a professor of atmospheric science at the University of Alabama; paradoxically, he is also a member of the IPCC and coauthored the report released early this year stating there is warming and it is of vast importance to correct. Christy is concerned with how poor nations will survive if fossil fuels are restricted or taxed beyond their ability to purchase; these nations rely heavily on fossil fuels for their existence. He claims the measuring devices are flawed and, to prove it, did his own research, analyzing data from satellites which measured the temperature of the lower troposphere (the five miles of atmosphere directly above the Earth's surface). While Christy, along with his colleague Roy Spencer, were eventually presented an award by the American Meteorological Society for "fundamentally advancing our ability to monitor climate" (qtd. in Royte 71), he is disappointed that his conclusions are not being used in reports analyzing global warming by organizations and research groups. Instead of warning against burning fossil fuels, Christy "Contends that the best thing for third-world countries that burn wood for fuel and heat is to build coal-fired power plants. ‘Cheap and accessible energy means better and longer lives. It means scientific and societal advances; it enhances health and security'" (72). While there are flaws in some of the measuring devices for temperature changes, they can't all be wrong. John Christy is concerned that human lives will suffer because of policies that may be adopted in an effort to curb global warming, he does not address the issue of lost lives due to massive flooding as a result of rising seas. He is very certain of his own conclusions, yet does not acknowledge the rise in ocean temperature, the slowing of convection currents, or the devastating droughts and floods already being experienced by third-world countries.

A second scientist of note, Richard S. Lindzen, professor of meteorology at the Massachusetts Institute of Technology, also claims there is insufficient evidence of global warming. In his Regulation article, "Global Warming: The origin and Nature of the Alleged Scientific Consensus," Lindzen contends that the computer models are unable to correctly determine what will happen when and if the CO2 deposits in our atmosphere double. He also makes the claim that funding issues is the reason scientists are supporting each other in proposing global warming as a fact. The science of climatology lost funding in the early 1990s and Lindzen asserts that by providing the possibility of an impending catastrophe, climatology scientists are able to justify investment by interest groups in further research. The sponsor of Regulation is The Cato Institute, which analyzes business and government policies; as a contributor, Lindzen is questioning the unintended consequences of policies that could be adopted as a fact. Because this article was published back in 1992, many of the computer models he refers to were inadequate at predicting the future scenarios connected to the increase of CO2 in our atmosphere and the greenhouse effect. As with John Christy, Richard Lindzen is a scientist who is concentrating diligently on his own contribution to the science of climatology and meteorology without acknowledging there might be another viewpoint. Or there might be disastrous consequences that result in loss of lives. Perhaps Mr. Christy and Mr. Lindzen are more interested in being right in their own conclusions than in the world's populations that are even now battling the consequences of global warming. What is disturbing about Mr. Lindzen's article is a lack of sources for the information he included.

John Christy and Richard Lindzen are not the only nonbelievers; there are numerous scientists, government officials and businessmen who dispute global warming as a fact and feel the scenarios and predictions are exaggerated. But it is not easy to find objective viewpoints containing rebuttals to the existence of the greenhouse effect and global warming. Most often, those who do contribute their opinion have ignored addressing the conditions of the late 1990s and have avoided proposing their own scenarios. Even though science is based on proving proposed theories to be false, there should be a sense of responsibility by those disputing these climate-change theories toward informing the world's population of alternative scenarios. If these people are so sure the proposed theories are incorrect, then what is their solution? Those in Bangledesh who are experiencing devastating flooding more often today than in past years deserve to know why they are suffering. Merely stating it's not happening when physical conditions suggest otherwise is not enough. Those who dispute proposed theories of global warming need to also become part of the solution and move away from causing further problems by casting doubt on scientific data.

Preventing that Meltdown

Based on reports in the media and various scientific predictions, it appears the future of our world is all doom and gloom—and that the Earth will self-destruct soon if we don't stop burning fossil fuels immediately. While it would be extremely beneficial to our health and the health of the Earth if we could stop contributing to the greenhouse gases today, it is just not possible. Our world depends upon the energy provided by fossil fuels; in addition, many countries are economically dependent upon the revenues those fuels provide them. As an example, the Organization of Petroleum Exporting Countries (OPEC) are opposed to the stringent reductions in the usage of fossil fuels which are proposed by the Kyoto Protocol because their entire economy is firmly based in the exportation of petroleum products (Sagan 161).

What is extremely difficult for most nations to acknowledge is that the world has become a global economy; travel worldwide is an everyday occurrence and boundaries between countries are easier to cross. No longer is America the independent nation that can cut itself off from the world simply because other countries' politics aren't to the liking of its leaders, as was the case in 1776. We are proud of that heritage, but times have changed in those 200-odd years and the world is a much different place. We are now more dependent upon other countries because our economies now intertwine due to the importing and exporting of goods globally. European nations have taken the first step toward becoming united economically by establishing the European Union, complete with a single form of currency, the Euro dollar, thus making it easier to do business between nations. Likewise, the Kyoto Protocol was one of the first steps in recognizing that in the major issue of global warming, we are in this world together—all nations. Consequently, it is the responsibility of all nations to acknowledge that global warming is a fact and that all countries will need to participate in reducing the usage of fossil fuels if we are to curb the gas emissions and prevent a meltdown. Carl Sagan summed up the situation nicely:

CO2 molecules, being brainless, are unable to understand the profound idea of national sovereignty. They're just blown by the wind. If they're produced in one place, they can wind up in any other place. The planet is a unit. Whatever the ideological and cultural differences, the nations of the world must work together; otherwise, there will be no solution to greenhouse warming and the other global environmental problems. We are all in this greenhouse together. (161)

While we wait and watch the politicians debate and posture over what looks to us to be unimportant details in relation to the consequences of global warming, the carbon dioxide continues to build in the atmosphere, lengthening the time it will take to turn around this out-of-control scenario. Each gas molecule stays in the atmosphere for decades, with each CFC molecule lasting a century or more (Christianson 147); this will result in a very gradual decline when we finally begin to slow the emission of those gases, making it imperative that we begin immediately. There are alternatives and solutions to the rapid growth of the greenhouse effect, but significant changes will require major efforts for all humanity.

Experiments are being conducted in laboratories around the world in attempts to discover and develop viable alternatives to burning fossil fuel resources, which will eventually result in a restructuring of methods to produce energy. DaimlerChrysler has developed a car that emits only water vapor from the tail pipe, while NASA's Ames Research Center is working on producing superefficient wind-power turbines; scientists in Japan are developing cheaply-produced solar cells that could "turn every house into its own electricity supplier" (Lemonick, "How To" 61). Fuel cells, invented in the 1800s, have been refined and reduced to fit in cars; through mixing hydrogen and oxygen, the car produces water and its own electricity which fuels it. These cars are expected to be available to consumers by 2004. Of course, solar panels have been used by consumers and businesses alike since the energy crunch of the 1970s. The super-thin solar cells being developed today will be inexpensive to install and more efficient than their present-day cousins (61-63).

Ideally, every factory, building, home and vehicle would have its own clean, renewable power source, eliminating oil wells, coal mines, power plants and power lines—and all the environmental disruption they cause. For now, though, the world has a more urgent mission: to stop the planet from overheating, and do it in a hurry. Thanks to the fuel cell cars and more advanced wind turbines and solar cells that are close to fruition, the global warming challenge seems a little less daunting than it did just a few years ago. (63)

In addition to large corporations developing new technology to replace fossil fuel as an energy source, we as consumers must begin to do our part, taking responsibility and becoming part of the solution instead of the problem. Supporting government representatives who support curbing greenhouse gas emissions is the first step in controlling contributions to global warming. Further conservation efforts on an individual level is a second step. "Americans put out an average of 20,000 lbs. of carbon dioxide (CO2) a year" ("What You" 39). We can improve our health through cleaner air and our pocketbooks through lowering energy bills by implementing personal conservation efforts. The Environmental Defense and World Wildlife Fund suggest the following actions:

• Carpool, walk, bike, or use mass transit whenever possible; the average CO2 reduction would be twenty pounds for each gallon of gas saved.
• Choose a fuel-efficient car that averages 30 miles per gallon of gasoline; the average annual CO2 reduction would be 2,500 pounds if the new car gets 10 miles per gallon more than your old one.
• Plant trees around your house and paint your house a dark color if you live in a cold climate or a light color if you live in a warm climate; the average annual CO2 reduction is about 5,000 pounds.
• Have your utility company do an energy audit of your home to find inefficiencies; the potential CO2 reduction is thousands of pounds per year.
• Set your water heater at 120°F or lower; the average annual CO2 reduction is 500 pounds for every 10°F adjustment.
• Wrap your water heater in an insulating blanket if it is more than five years old; the average annual CO2 reduction is up to 1,000 pounds.
• Install low-flow shower heads; the average annual CO2 reduction is up to 300 pounds.
• Replace worn out appliances with energy-efficient models; the average CO2 reduction for replacing a refrigerator is 3,000 pounds.
• Insulate all your walls and ceilings; the average annual CO2 reduction is up to 2,000 pounds.
• Caulk and weatherstrip around doors and windows; the average annual CO2 reduction is up to 1,000 pounds.
• Make sure the coolant in your car's air-conditioner is recycled whenever it is serviced; the equivalent CO2 reduction is thousands of pounds.
• Buy minimally packaged goods and reusable products and recycle everything possible; the average annual CO2 reduction is 1,000 pounds for just 25% less garbage.
• Set up a recycling program at your workplace; the average CO2 reduction is four pounds for every one pound of office paper that is recycled ("What You" 39).

Though these efforts may seem small in comparison to the enormity of the global warming issue and the predicted consequences, we can make a difference if enough people choose to participate in conservation efforts. By initiating our own programs, we can prove to our legislators that this is a crisis they need to help solve.

Patience is necessary—we must bear in mind that the final objective, a reversal of the increase in temperatures, may not be experienced in our lifetime. However, we will see a reduction of the CO2 emission output if we begin controlling the usage of fossil fuels today. As Carl Sagan points out, "Even if we stopped all CO2 and other emissions tomorrow, the greenhouse effects would continue to build at least until the end of the next century. This is a powerful reason to mistrust the ‘wait-and-see' approach to the problem—it may be profoundly dangerous" (145). Using fossil fuels more efficiently will allow us to begin weaning ourselves off them. Phasing in solar power, wind power, and hydrogen fuel technologies at a reasonable pace will ensure governments and businesses the ability to respond in a time frame that allows them to cut their dependence on fossil fuels while remaining profitable. Nothing can stop further warming immediately—the gases which are leading to the warming of the next fifty years were spewed into the air fifty years ago—but we must begin by making the commitment to change the effects on the atmosphere of the following fifty years. We cannot afford to continue to adopt this short-term foresight or we will all be suffering profoundly in the long-term.

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