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Hey guys, I am in a scientific research class in which we have to pick a topic and study that one topic and become an expert on it for a semseter. In the process you have to write a 12 pages doublespaced paper and have a 15 minute presentation. My topic is Global Climate Change. What I have wrote so far is below. Please read it and if you have any corrections or objections, please let me know:
Chris D. Jackson
Mr. Augustin
Scientific Research
04 March 2005
Our Future In The Balance: Global Climate Change and Civilization
In an age of terrorism and war, we often forget about an issue that is vital not only to our lives now, but to the future of civilization—global climate change. Global climate change is the term that refers to the changing of the Earth's climate over all timescales and includes all the workings of climate. Changes in the global climate can be brought on by both nature and human activity. However, in recent years, research shows that human activity is not only a factor in the process, but in fact is the main spark plug in the hastening of change in our climate. The brunt of the blame can be attributed to our over dependency and consumption of fossil fuels such as coal and oil. The burning of these fuels result in the release of powerful greenhouse gases such as carbon dioxide, methane, and nitrous oxide which are all major players in global climate change. We simply cannot continue down the current path of self destruction. It is our duty as citizens of the world to step up to the plate and recognize this all important issue and take the necessary steps to fight this predicament before it is too late.
In order to stop the rapid acceleration of climate change, we must first be able to recognize just what it is that is making our climate change so quickly. Many scientists believe the greenhouse effect is responsible. The greenhouse effect is widely recognized as the process in which the atmosphere absorbs incoming solar radiation but blocks outgoing thermal radiation. If not for the greenhouse effect, the Earth's surface would be frozen. However, instead of just keeping the Earth thawed out, the greenhouse effect has dramatically increased the surface temperature of the Earth due to record numbers of powerful greenhouse gases that are being emitted into the atmosphere. The most common and most dangerous gas in our atmosphere is carbon dioxide (CO2). Over hundreds of millions years, carbon dioxide has has closely shadowed global temperatures. Carbon dioxide is the one gas that humans are adding to the atmosphere at alarming rates triggering an accelerated climate change. Whenever we burn oil, coal, gas, or wood, carbon dioxide is emitted into the atmosphere. Approximately half of the carbon dioxide that is released is soon absorbed by the oceans or animals or by increased plant photosynthesis. However, there is an accumulation that creates a yearly rise of about 0.4% in the gas's presence in the air. Ever since 1800, the atmospheric concentration of carbon dioxide has risen steadily from about 270 parts per million to a present day level of 370 parts per million—a level which is higher than any time in the past twenty million years. The second most abundant greenhouse gas emitted by human activity is methane (CO4). Although smaller in concentration than carbon dioxide, methane, molecule to molecule, is about 20 times more powerful than carbon dioxide. Methane is produced by the decomposition of organic matter such as the guts of ruminant (hoofed) animals, landfills, and rice patties. Production and distribution of natural gas, oil, and coal also are sources of methane. The atmospheric concentration of methane according to recent studies, is increasing at a level of about 0.6% per year and the concentration of about 1.7 parts per million. Concentrations of methane are now higher than at any time in the past 420,000 years. Despite being less in abundance and power than carbon dioxide and methane, other gases such as nitrous oxide, ozone, and chlorofluorocarbons each contribute marginally to climate change. A third contributing factor to global climate change is population growth. The startling increase in human population since the mid 1900's has been coincided with two other important trends--the fast rise of carbon dioxide levels and average global temperatures. As the population has grown from 2.5 billion in 1950 to 6.2 billion in 2002, people have gradually expended larger quantities of fossil fuels and took part in more environmentally destructive activities such as fossil fuel combustion and deforestation (as previously mentioned), which both lead to the warming of Earth's temperatures. A third factor in global climate change is the depletion of the ozone layer. The ozone layer defends all life on Earth from the dangerous effects of the Sun's rays. The ozone layer has been shrinking for many years now, however, recently, the depletion has become more evident. According to NASA, the ozone hole over Antarctica has grown to its largest size yet—three times the size of the United States. Just between the years of 1999 and 2000, over 60% of the ozone layer surrounding the Arctic Circle was lost. A smaller ozone layer lets more ultra violent rays into the troposphere, the Earth's lower atmosphere, which causes warming on the Earth's surface. A fourth factor in our changing climate is deforestation. As everyone knows, trees play a very important role in the our environment. They serve as the largest mechanism for removing carbon dioxide from the air and also help shade the earth's surface. An acre of trees have the ability to absorb ten times the carbon amount absorbed by an acre of crop land or grassland. Going even further in-depth, it is reported that one tree absorbs thirteen pounds of carbon each year and that one acre of trees absorbs 2.8 tons of carbon annually. However, when the trees are cut down, all of the carbon dioxide stored inside is released into the atmosphere. Each day 5,500 acres of forests are cut down and over 50 million acres are destroyed each year. The combination of the lack of absorption and shading that trees provide each year, contributes greatly to the overall climate change. A fifth and final factor in global climate change is a phenomenon called global dimming. Global dimming is the decline in the amount of sun reaching the Earth’s surface. Global dimming can be attributed to modifications in clouds and air pollution that hinder the sun's ability to penetrate. Experts believe that the compounding of rising levels of artificial aerosol particles in the atmosphere and added moisture are causing the cloud cover to coalesce. It is now thought that the results of global dimming have cloaked the effect of global warming, and that resolving global dimming may have a huge and previously unforeseen influence on temperatures and sea levels. Studies that include the effects of global dimming advocate that world temperatures may go up by 2° Celsius © by 2030, and could rise as much as 10° C by 2100. If these predictions hold true, the increases would trigger the melting of the Greenland icecap, significant diminishment in tropical rain forests, and a substantial rise in seal levels around the world.
There is little doubt now that our planet is warming. Records from ice cores, which reveal levels of carbon dioxide in the atmosphere at a certain time, show clearly that with each passing year, the heat is rising. During the last century, temperatures around the world rose an average of 0.6° C with the rate of shift since 1976 at approximately three times that over the previous 100 years. In fact, nine of the ten hottest years on record have occurred in 1995 or later. (In order from 1-10: 1998, 2002, 2003, 2004, 2001, 1997, 1995, 1990, 1991, 1999) And according to a recently released NASA report, 2005 could become the hottest year on record due to a weak El Nino and large concentrations of human-made greenhouse gases being emitted into the atmosphere. In areas such as Sibera and Antarctica, temperatures have risen as much as 5° C—eight times faster than global averages. The dramatic increase in temperatures in these traditionally cold areas has led to the melting of permafrost, the buckling of roads, and the toppling of buildings. In Greenland, the ice cap is quickly loosing its thickness in coastal areas. Measurements show that Arctic sea ice has recently diminished by 250 million acres -- an area the size of California, Maryland and Texas combined. Studies also point out that Arctic sea ice has experienced a 40% reduction in its thickness within the past 30 years. The evidence of global climate change exceeds that just of the Arctic and Antarctica. Snow cover on the Earth's surface has decreased by 10% since the 1960's. Further, the yearly period in which lakes and rivers freeze over has decreased by two weeks. The world's glaciers and icecaps have also been disappearing at an alarming rate. For example, one of the world's most famous glaciers high atop Mount Kilimanjaro has lost 82% of its ice since 1912. In 1991, while hiking in the Alps on the border of Austria and Italy, explorers found the remains of Ötzi the Ice Man. What makes this discovery so significant is not the body of the Ice Man per se, which was greatly preserved by the ice, but how long it had been preserved under layers of ice. Tests results showed that Ötzi had been covered by ice for 5,300 years before his discovery in 1991, which further proves glaciers in present day are melting at a rate that hasn't been seen at any other time in history. The United States also is in danger of losing most of its precious glaciers. In Glacier National Park, Grinnell Glacier and Boulder Glacier have both lost 90% of their volume since 1850 and experts predict the glaciers will be completely gone within the next ten years. Although rising temperatures are a fundamental factor, glaciologists have found a very complicated, less obvious, cycle is at work. As the Pacific Ocean gets warmer, it creates troublesome El Nino climate patterns which occur more often and with more power. These climate patterns reduce precipitation, including new snows to renew glaciers around the world. Less snow also means glaciers become less white and more gray, which absorbs heat more. Then freshly unmasked rock walls serve as an oven to further speed melting. Whenever glaciers melt around the world, tons of melt water is dumped into oceans and seas daily. In the last century global sea levels rose by an average of 1-2 mm per year during and are projected to continue rising, with a predicted addition of 0.2-0.4 mm annually from melting glaciers. The rise in sea levels will affect a wide variety of areas which include coastal wetlands and lowlands, beaches and barrier islands, and ocean islands causing flooding, erosion, and saltwater invasion into aquifers and freshwater localities. An even more chilling thought to ponder is that half of the planet's inhabitants live within 50 miles of ocean coastlines. Even the average sea-level rise that was experienced throughout the 20th century led to widespread erosion and the loss of 100 sq km of wetlands annually in the US Mississippi River Delta. Presently in Trinidad and Tobago, as it is in many low-lying islands, beaches are diminishing several meters yearly and salinity levels have began to grow larger in coastal aquifers. Another example of the effects of global climate change is a more volatile climate. For instance, in 2004 alone Florida, the southeastern region of the United States, and the tropics was devastated by a series of powerful hurricanes within a small period of time. The cost was in the billions and in the case for the citizens of the tropics, the death toll was in the thousands. However, according to climatologists the worst is still to come. With the steady increase tropical sea surface temperatures stronger, more frequent, storms are expected. In fact, experts predict that an 80 year build-up of atmospheric carbon dioxide (CO2) at 1% per year, will lead leads to a one-half category increase in hurricane intensity and an 18% increase in precipitation close to the hurricane core. In this new era of volatile climate, it's not just powerful storms that we should worry about, but also the extreme heat waves such as the one in Europe in 2003. The killer heat wave ended up taking the lives of 60,000 Europeans. Many experts blame global warming for the heat wave saying that the changes in global sea temperatures that are taking place and unique conditions in the tropical area of the Indian Ocean were both factors in creating and maintaining settled air conditions over Europe. Even the recent tsunami that killed over 285,000 has been linked to global climate change. Environmentalists say that the steady rise in sea levels that are associated with warmer temperatures along with pollution and damage to coral reefs aided the strong wave as it crashed onto the coast of southeast Asia.
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