Global Warming: Act Now
Global Warming: Act Now
Global warming is one of the toughest environmental challenges today, and it threatens the health of people, wildlife, and economics around the world. According to the United States Environmental Protection Agency, the problem is mainly carbon dioxide and other fossil fuels. These fuels, like water vapor, methane, nitrous oxide, and ozone, are then collected like a blanket in the atmosphere. Energy from the sun is supposed to drive earth’s weather and climate and heat the earth’s surface, and in turn the earth radiates energy back into space. When the atmospheric greenhouse gases trap some of the outgoing energy, the heat is retained somewhat like the glass panels of a greenhouse. As a result, the planet becomes warmer. In fact, 2002 was the second warmest year on record, right behind 1998, and just ahead of 2001 (EPA). Although earth temperatures fluctuate naturally, warming over the past fifty years is the fastest in history and experts believe that the trend is accelerating. Scientists are working day and night to come up with ways and means to diffuse this problem, and many of them have been successful. The problem is that people do not seem to be interested in solving the problem. The knowledge of how to fix the problem is available, but the will to solve it is not.
It had previously been thought that global warming was a problem that started during the 20th century, but new research has led to new conclusions. Ruddiman (2005) reported that recent experiments had shown that concentrations of carbon dioxide began rising about 8,000 years ago. Around 3,000 years later, methane levels also began climbing. Both carbon dioxide and methane are heat trapping gases that contribute to the global warming problem. It is thought that human activity related to farming, primarily agricultural deforestation and crop irrigation, could have helped spike the methane and carbon dioxide levels in the earth.
Based on new studies by the Environmental Protection Agency (2002), the additional release of carbon dioxide by human activities has changed tremendously over the last hundred years. Fossil fuels are burned to heat homes and businesses, and power factories are responsible for about 98% of U.S. carbon dioxide emissions, 24% of methane emissions, and 18% of nitrous oxide emissions. Increased agriculture, deforestation, landfills, industrial production, and mining also contribute a significant share of emissions. In 1997, the Unites States emitted about one fifth of total global greenhouse gases (EPA). Global warming means more air pollution and problems with water supplies as precipitation patterns change, as well as huge threats to various ecosystems, such as the Amazon and glaciers.
In studies conducted by the Natural Resources Defense Council (N.R.D.C.) and reported by Gnanadesikan (2005), average temperatures have already risen, as well as the frequency of heat waves. According to the N.R.D.C., most of the United States has already warmed, in some areas by as much as four degrees. The last three five-year periods are the three warmest on record. Many places in North America had their hottest seasons or days in the 1990s. Another major threat of global warming could be droughts and wildfires.
The E.P.A. (2002) declared that another major threat of global warming could be deadly heat waves and the spread of diseases. More frequent and more intensive heat waves could result in more heat-related deaths. These conditions could also worsen local air quality problems already afflicting more than 80 million Americans. Global warming is expected to increase the potential geographic range and strength of tropical diseases as well. More than 250 people died as a result of an intense heat wave that gripped most of the eastern two-thirds of the United States in 1999. Disease-carrying mosquitoes are spreading as climate shifts allow them to survive in formerly inhospitable areas. Mosquitoes that can carry dengue fever viruses were previously limited to elevations of 3,300 feet but recently appeared at 7,200 feet in the Andes Mountains of Colombia. Malaria has also been detected in higher-elevation areas in Indonesia. Higher sea level is another major consequence of global warming. Current rates of sea-level rise are expected to increase as a result both of thermal expansion of the oceans and of partial melting of mountain glaciers and the Antarctic and Greenland ice caps. Consequences include loss of coastal wetlands and barrier islands, and a greater risk of flooding in coastal communities. Low-lying areas, such as the coastal region along the Gulf of Mexico, are especially vulnerable. The current pace of sea level rise is three times the historical rate and appears to be accelerating. Global sea level has already risen by four to eight inches in the past century. Scientists’ best estimate is that sea level will rise by an additional nineteen