In the early 1970s, the rise of environmentalism raised public doubts about the benefits of human activity for the planet and curiosity about climate turned into concern. In addition to the greenhouse effect, some scientists pointed out that human activity was putting dust and smog particles into the atmosphere, where they could block sunlight and cool the world. Moreover, analysis of weather statistics showed that a cooling trend had begun in the 1940s (Weart par. 6). The mass media were confused, sometimes predicting a globe with coastal areas flooded as the ice caps melted, sometimes warning of the prospect of a catastrophic new ice age. Study panels, first in the U.S. and then elsewhere, began to warn that one or another kind of future climate change might pose a severe threat, such as rising sea levels (par. 6). Research activity did accelerate, including huge data-gathering schemes that aet into action international communities of scientists (par. 6).
One unexpected discovery was that the level of certain other gases was rising, which would add to global warming. Some of these gases also degraded the atmosphere's protective ozone layer, and the news sparked public worries about the fragility of the atmosphere (par.7). In the late 1970s global temperatures had evidently begun to rise again. International panels of scientists began to warn that the world should take active steps to cut greenhouse gas emissions (par.7). Public concern finally focused on scientists' claims about the Earth's warming in the summer of 1988, the hottest on record. The many scientific uncertainties and the sheer complexity of climate made for intense political debate over what actions, if any, governments should take (par.8).
Scientists again intensified their research, organizing programs on an international scale. The world's governments created a panel to give the best possible advice, negotiated among thousands of officials and climate experts. Around the end of the century the panel managed to establish an agreement with little opposition (Global Warming par.4). However, Environmentalists and lawmakers spent the following years shouting at one another about whether the forecasts were true. Now that the serious debate has come to an end, “Global warming, even most skeptics have concluded, is the real deal, and human activity has been causing it” (Kluger, “Tipping Point” 35).
Without the greenhouse effect, however, life on Earth would not be possible. Energy from the sun is absorbed by the planet and radiated back out as heat. Atmospheric gases like carbon dioxide trap that heat and keep it from leaking into space. But, as humans pour ever increasing amounts of greenhouse gases into the atmosphere, more of the sun’s heat gets trapped, and the planet gets hotter. The amount of carbon dioxide in the atmosphere is climbing fast. Most of it comes from burning fuels for energy, such as gasoline in cars or coal for electricity.
“The U.S., with less than five percent of the world’s population, produces one quarter of all greenhouse gases” (Adams 38). About twenty percent of U.S. carbon dioxide comes from the burning of gasoline in internal-combustion engines of cars and light trucks (Global Warming: The Causes par. 4). Vehicles with poor gas mileage contribute the most to global warming—for each gallon of gas a vehicle consumes, twenty pounds of carbon dioxide are emitted into the air (par. 4). The United States is the largest consumer of oil, using 20.4 million barrels per day (par. 5). Senator Joseph Lieberman says, “If we can get three miles more per gallon from our cars, we’ll save one million barrels of oil a day, which is exactly what the (Artic National Wildlife) Refuge at its best in Alaska would produce” (qtd. in Global Warming: The Causes par. 5).
Deforestation, through cutting or burning, also wreaks havoc far beyond the affected area. It is the second principle cause of atmospheric carbon dioxide (par. 6). The fires release more carbon into the atmosphere, fewer plants survive to convey carbon dioxide into oxygen, and scorched soil absorbs more heat and retains less water, increasing droughts (Adams 38). Thirty-four million acres of trees are cut or burned each year. We are losing rainforests along with temperate forests. “The temperate forests of the world account for an absorption rate of two billion tons of carbon annually. In the forests of Siberia alone, the Earth is losing ten million acres per year” (Montaigne 35).
While carbon dioxide is the principle greenhouse gas, methane is second most important, only because there is less of it. It is more than twenty times as effective as carbon dioxide at trapping heat in the atmosphere (Kolbert 20). Levels of atmospheric methane have risen one hundred and forty-five percent in the last one hundred years (20). Methane is derived from sources such as rice paddies, bovine flatulence, bacteria in bogs and fossil fuel production. Most of the world’s rice paddies, and all of the rice in the U.S., are grown on flooded fields. “When fields are flooded, anaerobic conditions develop, organic matter in the soil decomposes, and methane is released into the atmosphere, primarily through the rice plants” (22).
Although most scientists believe global warming is the result of man-made pollution, there are those who believe that the Earth and other natural forces account for very little of the recent and rapid temperature changes.
Global climate and temperature cycles are the result of a complex interplay between a variety of causes. Because these cycles and events overlap, sometimes compounding one another, sometimes canceling one another out, it is inaccurate to imply a statistically significant trend in climate or temperature patterns from just a few years or a few decades of data. Unfortunately, a lot of disinformation about where Earth’s climate is heading is being propagated by “scientists” who use improper statistical methods, short-term temperature trends, or faulty computer models to make analytical and anecdotal projections about the significance of man-made influences to Earth’s climate. During the last one hundred years, there have been two general cycles of warming and cooling recorded in the U.S. We are currently in the second warming cycle. Overall, U.S. temperatures show no significant warming trend over the last one hundred years. This has been established but not publicized. (Global Warming par. 23-25)
Global warming or no global warming, the Earth is feeling the effect of rising global temperatures everywhere. Ice is shrinking, sea levels are rising, weather is worsening, and humans and animals have no time to adapt.
The snows of Kilimanjaro have melted more than eighty percent since 1812 (Glick 13). Glaciers in the Garhwal Himalaya in India are retreating so fast that researchers believe that most central and eastern Himalayan glaciers could disappear by 2035 (13). Artic sea ice has thinned significantly over the past half century, and its extent has declined by about ten percent in the last thirty years (14). NASA’s repeated laser altimeter readings show the edges of Greenland’s ice sheet shrinking (14). Massive ice fields, monstrous glaciers, and sea ice are disappearing fast.
When temperatures rise and ice melts, more water flows to the seas from glaciers and ice caps, and ocean water warms and expands in volume. This combination of effects has played the major role in raising average global sea levels between four and eight inches in the past hundred years (Adams 38). Every inch of sea-level rise could result in eight feel of horizontal retreat of sandy beach shorelines due to erosion (38). Also, when salt water intrudes into freshwater aquifers, it threatens sources of drinking water and makes raising crops difficult (39). “The Intergovernmental Panel on Climate Change projected in its 2001 report that sea level will rise anywhere between four and thirty five inches by the end of the century” (Glick 27). How much the sea will rise depends on how much carbon dioxide and other greenhouse gases we continue to emit. In Bangladesh, at just over three feet of rise, seventy million people could be displaced (27). Seventy-five percent of coastal Louisiana wetlands would be destroyed at just over one and a half feet (27). At even further risk of flooding are the low-lying South Sea Islands, which would flood with only a four inch rise in sea level (27).
For years environmentalists have warned that one of the first and most reliable signs of severe global warming would be an increase in the most violent storms, such as the recent hurricanes Rita and Katrina. Meteorologist Greg Holland says, “The odds have changed in favor of more intense storms and heavier rainfalls. These are not small changes. We’re talking about a very large change” (qtd. in “Global Warming: The Culprit” 43). Warmer air makes warmer oceans, which in turn drive hurricanes. The temperature causes the amount of water vapor in the air to increase, and that moisture helps feed storms. Another negative effect of global warming on the weather and climate is drought. Higher temperatures bake moisture out of the soil faster, causing dry regions, such as the Western U.S. and Africa, to suffer drought (Adams 39). “The percentage of Earth’s surface suffering drought has more than doubled since the 1970s” (41).
Ecosystems too are being bothered by global climate change. “This is the first instance in which humans appear to be accelerating the change, and warming could take place so quickly that species will not have the time to adapt and avoid extinction” (Montaigne 41). Different species react to climate change in different ways, and as a result, the natural cycles of co-dependent creatures—such as birds and the creatures they feed on, along with plants and the insects that pollinate them—may fall out of order, causing populations to decline (42). Marine life is taking a hard hit in the form of coral bleaching—a loss of nutritious algae that live in the coral caused by temperature increase (42). Reefs usually recover from bleaching incidents activated by short-term warming (42). However, rising average ocean temperatures are causing longer and more frequent bleaching episodes that are fatal to some corals, such as Australia’s Great Barrier Reef (42).
As the species causing all the problems, we’re suffering the destruction of our habitat too.
It’s a fair bet that global warming is going to lead to a rise in human sickness and death. But what form they will take is difficult to say. We can be pretty sure that as average temperatures climb, there will be more frequent and longer heat waves of the sort that contributed to the death of at least 20,000 Europeans in August 2003. (Gorman, 44)
Rising temperatures could—if rainfall and other conditions are right—result in larger mosquito populations at higher elevations in the tropics, which in turn would contribute to the spread of malaria, dengue, and other insect-caused infections (44). The World Health Organization (WHO) believes that even the smallest increases in average temperature that have occurred since the 1970s have begun to take a toll on life (44). Climate change is responsible for at least 150,000 extra deaths a year, a figure that is predicted to double by 2030 (45). Rising temperature also increases the amount of ground-level ozone; a major element of smog (45). Many studies have linked higher ozone levels to death rates from heart and lung illnesses resulting cities issueing smog alerts to warn those at risk to stay indoors. These alerts are expected to become more frequent and last for longer periods of time (45). Another predicted consequence of global warming is heavier downpours, leading to more floods. The instant danger is drowning, but the bigger issue is water quality (45). A heavy rainfall paved the way for the majority of waterborne-disease outbreaks in the U.S. over the past sixty years (Flannery 148).
The tricky thing about all those predictions is that you can’t point to any outbreak or any individual’s death and say, “This occurred because of climate change.” But we know that good public health relies on a long list of factors—the availability of doctors and nurses, effective medicines, clean water, proper sanitation—and that even today, millions of people die every year of what should be preventable diseases. With global warming, you can expect the death toll to be even higher. (Gorman 45)
“The climate of our past is our anchor for looking at the future,” says paleoclimatologist Cathy Whitlock (qtd. in “Now What?” 75). “If we can understand the past linkages between the ocean, atmosphere, and biosphere, and determine which parts were the really big players in past sudden change, then maybe we can better deal with future surprises.” Although Earth’s climate has yet to be fully understood, computer technology has made big steps in predicting what the weather will be like in the near future. The warming doesn’t mean that every place will suddenly become like Miami. Some areas, like the interior of the U.S., are likely to grow hotter and drier (Morell 75). Other areas, like China, Southeast Asia, and the western U.S., may get more precipitation but less snowfall (75). Sea levels around the world are projected to rise as the last of the glaciers melt. Intense hurricanes may occur more frequently and damage costal cities. Heat waves may become the summer norm (75). “We would need to get zero emissions to stabilize the carbon dioxide that’s already in the atmosphere. That’s not the path we, as societies, have chosen. Even if we were to stop carbon dioxide emissions now, we are committed to warming” (Kolbert 168). Taking into account the opposing argument that climate is changing of its own accord and humans have little to do with it, climate is still changing. In the end it’s going to be a very different world.
