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Is Global warming a real threat? Or just an exaggeration
Global warming refers to an increase in average temperature of the earth's surface, atmosphere and oceans. Research indicates that global warming phenomenon is greatly contributed by man's activities. In 1986 a team of scientist from eleven countries including the United States of America issued a report warning the world that human activities such as production of energy by burning fossil fuels, use of automobiles and deforestation could lead to arise in global temperatures due to green house effect that comes as a result of these activities. Green house effect can be defined as a warming process that comes as a result of high levels of heat-trapping gases (green house gases) such carbon dioxide, water vapor and oxides of nitrogen such as nitrous oxide and nitrogen dioxide. Normally the solar energy that reaches the earth is absorbed by the oceans and the earth surface and most of it is radiated back into space. When small concentration of water vapor and green house gases such as carbon dioxide are present in the atmosphere, they absorb this radiated energy and consequently convert it to heat which they can either retain or reflect it back to the earth's surface. This trapped heat results in formation of a blanket of warm air around the earth and moderates the climate patterns and global temperature trends (Maslin, 2007).
The argument by scientist in 1980s that human activities could lead to lead to increase in global temperature as a result of green house effect was based on the theory proposed by a Swedish chemist Svante Arrhenius, who in 1896 hypothesized that, burning of coal and other fossil based fuels produced a lot of carbon dioxide that could trap heat and lead to increase in global temperatures. This global warming theory never captured the world attention until 1988 when James Hansen, an atmospheric scientist, gave a testimony before the U.S. senate committee that pollutants produced by human activities were causing the global temperatures to increase rapidly. He also warned that if this trend continued; the world would face disastrous climatic change that will negatively affect the environment and human survival (Moore, 1996).
Most climatic and environmental researchers were unconvinced and cynical about Hansen's warning initially. The levels of carbon dioxide in the atmosphere had increased by 30 % since mid 1700s when industrial revolution begun. The global temperatures had also increased by one degree Fahrenheit (F) during the twentieth century- a figure which is considered the largest increase of any century during the past millennium. Many climatologists attributed the one degree change in global temperature to natural variability of the planet's weather. They did not consider industrial revolution as a cause of the temperature trends that were being experienced (Maslin, 2007).
Things started changing when further researches were carried out and data that supported the global theory that had been proposed by Arrhenius started mounting. For instance in 1995, an intergovernmental panel on climate change (IPCC), united nation subcommittee that comprised of over 2000 environmental scientist emphasized that human activities such as industrialization were partly responsible for the increasing global temperatures. This panel also predicted that by the year 2100, if the trend continues, the levels of carbon dioxide in the atmosphere will double and consequently cause temperatures to rise from 2 to 10.4 degrees Fahrenheit (F). Analysts warned that such levels of global temperature would lead to many catastrophic consequences that will adversely hurt human health and survival. These warnings included high incidences of floods, heat waves, drought, economic crises, infectious diseases, hurricanes, wild fires and storm-related deaths. Many of these warnings have so far been long-established.
For instance, the weather of 1990s was considered the hottest on record. Also in January 1998, storm ice left four million people without power in northern England. Other catastrophic incidences that happened during this year included: the rainforests that were destroyed by wild fire in Mexico and Brazil and the summer that was characterized by killer heat waves in Texas, Middle East and India (Spencer, 2000). The year that followed set a record of drought in Mid - Atlantic States and the heat wave that followed in the Midwest and north eastern U.S claimed 271 lives. It is also during the year 1999 that a super a super cyclone in eastern India claimed 10,000 people. Some climatologists have maintained that the harsh weather that was experienced in the 1990s cannot necessarily be connected to high levels of green house gases or an increase on global temperatures (Falkowski, 2003).
How serious is global warming?
Some researchers have pointed out that the predictions that were made by IPCC's about the phenomenon of global warming were highly founded on computer-based climatic stimulations which have so far proved not to be dependable. This argument seem to be valid because it has been found out that global temperatures taken on ground, from weather balloons and from satellites disagree with the projections of computer-based stimulations. For instance, the warming trend of the lower troposphere has been recorded and the data is contrary to predictions by climatic stimulators that indicated troposphere warming should have already taken place due to high levels of carbon dioxide in the atmosphere. Although it is agreed among scientists that global warming is a reality, skeptical scientists assert that the unreliability of the IPCC's predictions poses serious doubts about the likely severity of global warming (Catesson, 2007).Want an expert to write a paper for you Talk to an operator now
Environmentalists have argued that if the trend of global warming continues unchecked, it will threaten even the world's most diverse natural areas. The habitat is at risk and a strong correlation between species loss in globally significant terrestrial ecosystems and global warming in the near future is very strong. This is because global warming is likely to lead to a change of habitat to many species hence resulting to extinction because many species will not be able to move fast enough to new habitats to survive. Global Warming poses a disastrous danger of extinction for species in one-fifth of the world's most prone area especially the poles where the polar bears are at a great risk of extinction. Many ecosystems in the United States are at risk, a fact that has been greatly contributed to global warming.
For instance if has been argued that if global warming continue scaling up, it may ruin the shrub and woodland areas that stretch from southern California to san Francisco(Falkowski, 2003). Other areas in the United States that are likely to be worst hit include; Sierra Nevada Mountains, prairies in the northern heart of the United States, Sonoran- Baja deserts across the southwestern united states and Klamath Siskiyou forest that is situated near California-Oregon border. Some of the prone areas in other parts of the world that are likely to be devastated by the effects of global warming include the Ural mountain and Daurian steppe of Mongolia and Russia, the Canadian low arctic tundra, southwestern Australia, the Tera-Duar savannah of north eastern India and Flanbos of South Africa and many others.
Global temperatures are expected to continue rising as human activities continue to generate more carbon dioxide, methane, nitrous oxide and other green house gases. It is because of this that most parts of the United States are projected to experience and increase in average temperature. The effect of climatic changes, that is; whether it will be beneficial or harmful will depend on the region and time and also the ability of different societal and environmental systems to acclimatize or get by the change (Falkowski, 2003).
The world mountainous regions form habitat to more than eight million people, also this regions are the major source to major rivers in the world. Runoff in these regions is greatly affected by temperature thus suggesting a very strong correlation between global warming and floods in the lowlands. According to researches that have been carried out, floods have occurred more regularly in the latest years than in the past and they have predicted that global warming will result in such floods occurring even more often in the future. Researchers have further predicted that if the global temperatures continue to increase at the rate of two degrees Celsius, the large floods that used to occur after every century will occur up to five times more often. Despite these predictions, there has been lack of scientific agreement on the effect of temperature deviation and floods (Allamano, 2009).
Researches indicate that alpine glaciers of the world are losing mass at a very high rate a fact that many scientists have correlated with increased global heat. This trend is likely to continue if global warming is not controlled. Glaciers in the alpine region are of great significance because they act as buffers. The glaciers store water during the rainy season and during the dry season the melt water helps to maintain river systems. It is estimated that 1.5 to 2 billion people in America (Andes and Rocky mountains), Asia (Himalayan region) and in Europe (Alps) depend on river systems with glaciers inside their catchment areas. Glacier retreat has been rapid worldwide since 1850 and has led to scarcity of water for irrigation, domestic use and for animals and plants. Studies for instance indicate that Boulder glacier in North America retreated 450 m between1987 and 2005 (U.S environmental protection Agency2007). This is an alarming trend that is if continues will compromise the survival of human being and all organisms that depend on water from this sources.
Over the next century environmental professionals and researchers are predicting that the effect of global warming will persist at a constant inclined graph. Scientists further believe that if this trend continues the global temperature will increase between 2 and 9 degree Fahrenheit in 2050. Climatic models indicate that if the global temperature increase at an average of 3 degrees Fahrenheit, the temperature at the arctic region will rise by seven degrees. Consequently oceans throughout the world will become full as a result of melt ice or glacier. This will cause the levels of the oceans to rise by at least 7 feet. As temperature will continue to scale up, the oceans will evaporate at an abnormal rate thus more rains will be experienced. This heavy rainfall will hit vulnerable parts of the world for instance subtropical regions leading to enormous floods and monsoons. Predictions also indicate that global warming will be associated with some benefits. For instance the northern parts of the world, the warmer temperatures will lead to more rainfall and thus longer growing season that will bring to an end food shortage (Falkowski, 2003). Other studies indicate that global warming will lead to reduced agriculture yields in many parts of the world and diseases like malaria will return to area where they had been extinguished earlier (Catesson 2007).
According to outcomes from researches, the Polar Regions are projected to be the worst hit by global warming. The Polar Regions includes the arctic in the northern hemisphere and Antarctic in the southern hemisphere. The arctic region consists of frozen ocean surrounded by land that is a habitat to more than four million people. This region includes some or all the territories of eight nations including the U.S. On the other hand, Antarctic which is uninhabited ice covered continent that is surrounded by ocean. Research by scientist indicate that arctic is expected to experience greatest rates of warming as compared to the rest of the world a fact they attribute to great reflective nature of ice as compared to the ocean or land (Spencer, 2000).
The arctic climate impact assessment (ACIA) report released in 2004 by scientist (IPCC, 2007) concluded that the average temperature in the arctic region have gone up by almost twice the rate in the past few decades when compared to the rest of the world. The strong arctic warming is further supported by the extensive melting of glaciers and sea ice and increasing permafrost temperatures. This report indicates that these trends are expected to continue at an accelerated rate during this century because of the increasing levels of green house gases from increased human activities. The melting of glaciers is the major contributing factor to increasing sea level, and is considered to be a serious threat to those living at coastal lowlands. High levels of green house gases lead to acidification of ocean thus adversely affecting marine calcifies by making it very hard for these organisms to form protective shells. Also reduction in levels of sea ice has overwhelming consequences for the survival of polar-bears, ice-dependent seals and the local people who depend on these animals as a primary source of food (U.S Environment Protection Agency, 2007).
The ACIA report further indicated that the arctic impact will have far reaching effects in terms of biodiversity because migratory species depend on this area as feeding and breeding grounds. This report also assessed the proposed planting of trees in order to curb greenhouse effect. It was indicated that although increased number of trees will lead to reduction in the levels of carbon dioxide which is a major green house gas; the trees will also absorb more sunlight because the land surface will become darker and less reflective. This will again lead to warming in the arctic regions. Although the reduced sea ice has many detrimental effects, it is also associated with some positive aspects.
For instance some scientists argue that reduced sea ice will lead to increased accessibility of the resources in arctic regions and increased opportunities for shipping and probably offshore oil extraction (IPCC, 2007). Like the arctic, Antarctic region has also been experiencing effects that are greatly contributed to the climatic change in the region. Over the last century there has been warming trend in the Antarctic Peninsula whish has led to major retreat and reduction of ice shelves. Scientists argue that the melting of this ice shelves have little effect on the sea levels because; since they were initially floating their melting does not increase the sea level. Therefore melting of ice is likely to increase accessibility of the region without posing so much threat to survival (Spencer, 2000).
This phenomenon of global warming is even being seen by some optimistic researchers who argue that maintaining a warmer earth will give rise to lusher forests, reduced energy cost, increased food production and a much more improved human health. Contrary to this opinion many environmentalist and scientists fear that uncontrolled global warming would result in a striking increase in extreme weather that will consequently rip up regional population, bump up the spread infectious diseases and destabilize world economies (Catesson, 2007).
Therefore basing our argument on various scientific evidences such as melting of ice caps and glaciers; it is obvious that global warming is a real threat. It is increasingly becoming clear that increased human activities such as deforestation and burning of fossils are playing a big role in increasing global temperatures due to green house effect. Since these activities are projected to continue in the foreseeable future, the earth will continue warming. According to scientific evidence, global warming is associated with devastating effect such as increased levels of droughts, floods, melting of ice at arctic; therefore global warming if goes uncontrolled it going to be a big threat. Although some studies have argued the contrary, I think global warming is a real threat and not an exaggeration but the degree to which it is threatening life is subject to debate.