Essay on GLOBAL WARMING – Fact or Fiction
June 26, 2010 neoenglish CSS and PMS
Introduction to Global Warming:
Greenhouse warming has existed for quite some time, arguably since Earth was first formed. Greenhouse gases, or gases conducive to the greenhouse effect, act like a blanket or the panes of glass in a greenhouse’s walls; they reflect the heat the earth would radiate into space back down towards the earth, holding it in. You see, the balance of heat on earth is maintained by different processes. Solar radiation approaches the earth, and clouds and the atmosphere reflect some of it back into space.
More radiation is absorbed by the atmosphere, clouds, and the surface of the earth. Then the earth radiates the heat back as infrared radiation. To maintain a certain, constant temperature, the rate that Earth emits energy into space must equal the rate it absorbs the sun’s energy. The greenhouse effect’s refusal to allow a certain amount of this terrestrial radiation to pass keeps the Earth’s average surface temperature at about 60°F (15°C). If there were no greenhouse gases in the atmosphere, most of the heat radiated by the Earth’s surface would be lost directly to outer space, and the planet’s temperature would be 0°F (-18°C), too cold for most forms of life (Greenhouse).
There are several atmospheric gases that act as greenhouse gases (GHGs). The most infamous is carbon dioxide, which is emitted through the respiration of humans and animals, the burning of fossil fuel, deforestation, and other changes in land use. Carbon dioxide is the main focus of many greenhouse gas sanctions, since it is the greenhouse gas that has most been released into the atmosphere. However, some other gases may have a greater effect upon climate than CO2. If one examines research into the possible warming effect of other GHGs relative to CO2, one finds that over a 100-year period, there are gases present in far smaller amounts that have a much more concentrated effect. Methane, a gas produced by livestock (flatulence), oil and gas production, coal mining, solid waste, and wet rice agriculture, has 11 times more warming potential per volume than CO2 (Science), or 25 times more per molecule (Clarkson). Nitrous oxide, produced mainly in connection with current agricultural practices, has 270 times more warming potential per volume over this period than CO2 (Science). Chlorofluorocarbons (CFCs), the gases used as refrigerants and in aerosol spray dispensers that were banned some time back due to their ozone depletion potential, have 3400-7100 times more warming potential per volume than CO2 (Science). Hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), the CFC substitutes, have a slightly smaller warming potential at 1200-1600 times larger per volume than CO2 (Science).
And so, as one might infer, studies are showing that additions of GHGs may cause the earth to get warmer than it naturally would. This is what is referred to as anthropogenic (human-caused) global warming. Many times, the terms global warming and climate change are used interchangeably. (We will do the same, for continuity’s sake.) But, this is not correct and the concepts are different. Climate change includes precipitation, wind patterns, and temperature. It also refers to the whole climate, not just weather conditions of one place. Global warming is an indication of climate change. It is an example of a climate change that has the atmosphere’s average temperature increase. Earth has experienced much warming and much cooling throughout its history. There is a great deal of debate as to whether or not the earth is experiencing a globally warming climate change and, if it is, whether the underlying causes are man-made or natural. Different research has given different results.
However, even when greenhouse gases were arguably at a stable level, before the onset of the Industrial Revolution, Earth’s climate tended to fluctuate widely. A period from 5,000 to 3,000 BC (when civilization began) is called the Climatic Optimum and another period from 900 – 1200 AD is called the Little Climatic Optimum or the Medieval Climatic Optimum, both so named for their unusually warm temperatures. Likewise, a period from 1550 to 1850 is known as the Little Ice Age for its unusually cold temperatures (Pidwirny). At this time, glaciers in southern Norway reached their greatest extent in 9000 years (Keigwin). With such large variations possible, it is difficult to know where the next natural fluctuation could take us. Perhaps those who find that global climate is warming are simply measuring a natural fluctuation. Or perhaps a natural fluctuation is masking the real effect of GHGs on the globe.
Global Warming: Big Questions, Big Research
As mentioned previously, there is a great debate over whether or not humans are causing global warming. Some activists and researchers have resorted to name-calling or accusing the opposing side of having “sold out” to one special interest or another. As mentioned previously, we have attempted to cut away the personal attacks between the opposing sides, search for the kernel of truth (or logic, where truth cannot be discerned), and get down to the heart of the matter.
In order to properly read any of the reports or research on global climate change, one must keep in mind that nothing (or almost nothing) is certain. Everything has a certain degree of uncertainty, a certain flavor of the unknown. There really is no conclusive evidence of global warming, and many scientists in favor of the global warming hypothesis say that it will be a decade or more before it is possible to develop any substantial evidence. As an anonymous senior climate modeler has said about global warming, “The more you learn, the more you understand that you don’t understand very much” (Kerr – Greenhouse Forecasting). Global climate is by nature always fluctuating, and that only adds to the confusion about anthropogenic global warming. If there were an anthropogenic global warming, we couldn’t be sure what temperature we were supposed to be at, as climate shifts are a natural part of life on Earth. Compounding that confusion is natural variability, which is always working to confuse researchers just as they come close to attributing a perceived change in average temperature to some external factor, such as atmospheric composition (GHGs) or solar variation. One reason for this variability is the long adjustment time of the oceans’ heat storage and current systems. It is estimated to take several hundred years for water to circulate from the deepest portions of the oceans back to the surface. This means that if, for example, a pool of extra cold water is singled out and stored in the depths by some freak mechanism, it could stay there a century or two before resurfacing and producing a local, cool climate change (Clarkson, North, and Schmandt).
Since no one can create another Earth (let alone one that behaves exactly like ours) and perform atmosphere-altering experiments on it, we are left with the alternative of theorizing based on observations. In other words, the only way we can purport to know anything about what might be changing in our climate is by playing with data, such as records of temperature, borehole measurements, etc., and seeing what scenarios the data will agree with.
Most of the body of global warming theory is based on computerized climate models called global circulation models or GCMs, for they are almost the only tools global warming researchers have. GCMs are difficult to make as making them properly involves a deep-rooted understanding of the way the atmosphere works and how its actions are interconnected with other planetary bodies, such as the oceans or the terrestrial biosphere. But our understanding of the inner workings of the atmosphere and the ways it relates to other planetary bodies is not very good. Renowned NASA climate modeler James Hansen, the man whose summer 1988 congressional testimony kicked off the climate change debate, states in the Proceedings of the National Academy of Sciences: “The forcings [outside factors] that drive long-term climate change are not known with an accuracy sufficient to define future climate changes.” One of the fundamental illustrations of chaos, the butterfly effect, displays the interconnectedness of the atmosphere system when it states that a butterfly fluttering through the air in China could cause rain in New York the following spring.
GCMs are made by formulating mathematical descriptions of the interrelationships between the atmosphere/ocean/biosphere/cryosphere system and conducting numerical experiments. They certainly are unable to form a mathematical description based on the kind of interconnections, or feedbacks, that the butterfly effect would suggest. Indeed, Michael Schlesinger, modeler at the University of Illinois, Urbana-Champaign, tells us that “in the climate system, there are 14 orders of magnitude, from the planetary scale–which is 40 million meters–down to the scale of one of the little aerosol particles on which water vapor can change phase to a liquid [cloud particle]–which is a fraction of a millionth of a millimeter.” Of these 14 orders of magnitude, only the two largest (the planetary scale and the scale of weather disturbances) can currently be included in models. Schlesinger notes that, to include the third order of magnitude (the scale of thunderstorms, at about 50 km resolution) a computer a thousand times faster would be necessary, “a teraflops machine that maybe we’ll have in 5 years.” Including all orders of magnitude would require 1036-1037 times more computing power (Kerr – Greenhouse Forecasting).
Because GCMs are so hard to make, often they account for the same processes differently; two models may have two different mathematical descriptions of what effect clouds have on warming, for example. Processes with a resolu
Essay on GLOBAL WARMING – Fact or FictionJune 26, 2010 neoenglish CSS and PMSIntroduction to Global Warming:Greenhouse warming has existed for quite some time, arguably since Earth was first formed. Greenhouse gases, or gases conducive to the greenhouse effect, act like a blanket or the panes of glass in a greenhouse’s walls; they reflect the heat the earth would radiate into space back down towards the earth, holding it in. You see, the balance of heat on earth is maintained by different processes. Solar radiation approaches the earth, and clouds and the atmosphere reflect some of it back into space. More radiation is absorbed by the atmosphere, clouds, and the surface of the earth. Then the earth radiates the heat back as infrared radiation. To maintain a certain, constant temperature, the rate that Earth emits energy into space must equal the rate it absorbs the sun’s energy. The greenhouse effect’s refusal to allow a certain amount of this terrestrial radiation to pass keeps the Earth’s average surface temperature at about 60°F (15°C). If there were no greenhouse gases in the atmosphere, most of the heat radiated by the Earth’s surface would be lost directly to outer space, and the planet’s temperature would be 0°F (-18°C), too cold for most forms of life (Greenhouse). There are several atmospheric gases that act as greenhouse gases (GHGs). The most infamous is carbon dioxide, which is emitted through the respiration of humans and animals, the burning of fossil fuel, deforestation, and other changes in land use. Carbon dioxide is the main focus of many greenhouse gas sanctions, since it is the greenhouse gas that has most been released into the atmosphere. However, some other gases may have a greater effect upon climate than CO2. If one examines research into the possible warming effect of other GHGs relative to CO2, one finds that over a 100-year period, there are gases present in far smaller amounts that have a much more concentrated effect. Methane, a gas produced by livestock (flatulence), oil and gas production, coal mining, solid waste, and wet rice agriculture, has 11 times more warming potential per volume than CO2 (Science), or 25 times more per molecule (Clarkson). Nitrous oxide, produced mainly in connection with current agricultural practices, has 270 times more warming potential per volume over this period than CO2 (Science). Chlorofluorocarbons (CFCs), the gases used as refrigerants and in aerosol spray dispensers that were banned some time back due to their ozone depletion potential, have 3400-7100 times more warming potential per volume than CO2 (Science). Hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), the CFC substitutes, have a slightly smaller warming potential at 1200-1600 times larger per volume than CO2 (Science). And so, as one might infer, studies are showing that additions of GHGs may cause the earth to get warmer than it naturally would. This is what is referred to as anthropogenic (human-caused) global warming. Many times, the terms global warming and climate change are used interchangeably. (We will do the same, for continuity’s sake.) But, this is not correct and the concepts are different. Climate change includes precipitation, wind patterns, and temperature. It also refers to the whole climate, not just weather conditions of one place. Global warming is an indication of climate change. It is an example of a climate change that has the atmosphere’s average temperature increase. Earth has experienced much warming and much cooling throughout its history. There is a great deal of debate as to whether or not the earth is experiencing a globally warming climate change and, if it is, whether the underlying causes are man-made or natural. Different research has given different results. However, even when greenhouse gases were arguably at a stable level, before the onset of the Industrial Revolution, Earth’s climate tended to fluctuate widely. A period from 5,000 to 3,000 BC (when civilization began) is called the Climatic Optimum and another period from 900 – 1200 AD is called the Little Climatic Optimum or the Medieval Climatic Optimum, both so named for their unusually warm temperatures. Likewise, a period from 1550 to 1850 is known as the Little Ice Age for its unusually cold temperatures (Pidwirny). At this time, glaciers in southern Norway reached their greatest extent in 9000 years (Keigwin). With such large variations possible, it is difficult to know where the next natural fluctuation could take us. Perhaps those who find that global climate is warming are simply measuring a natural fluctuation. Or perhaps a natural fluctuation is masking the real effect of GHGs on the globe. Global Warming: Big Questions, Big ResearchAs mentioned previously, there is a great debate over whether or not humans are causing global warming. Some activists and researchers have resorted to name-calling or accusing the opposing side of having “sold out” to one special interest or another. As mentioned previously, we have attempted to cut away the personal attacks between the opposing sides, search for the kernel of truth (or logic, where truth cannot be discerned), and get down to the heart of the matter. In order to properly read any of the reports or research on global climate change, one must keep in mind that nothing (or almost nothing) is certain. Everything has a certain degree of uncertainty, a certain flavor of the unknown. There really is no conclusive evidence of global warming, and many scientists in favor of the global warming hypothesis say that it will be a decade or more before it is possible to develop any substantial evidence. As an anonymous senior climate modeler has said about global warming, “The more you learn, the more you understand that you don’t understand very much” (Kerr – Greenhouse Forecasting). Global climate is by nature always fluctuating, and that only adds to the confusion about anthropogenic global warming. If there were an anthropogenic global warming, we couldn’t be sure what temperature we were supposed to be at, as climate shifts are a natural part of life on Earth. Compounding that confusion is natural variability, which is always working to confuse researchers just as they come close to attributing a perceived change in average temperature to some external factor, such as atmospheric composition (GHGs) or solar variation. One reason for this variability is the long adjustment time of the oceans’ heat storage and current systems. It is estimated to take several hundred years for water to circulate from the deepest portions of the oceans back to the surface. This means that if, for example, a pool of extra cold water is singled out and stored in the depths by some freak mechanism, it could stay there a century or two before resurfacing and producing a local, cool climate change (Clarkson, North, and Schmandt). Since no one can create another Earth (let alone one that behaves exactly like ours) and perform atmosphere-altering experiments on it, we are left with the alternative of theorizing based on observations. In other words, the only way we can purport to know anything about what might be changing in our climate is by playing with data, such as records of temperature, borehole measurements, etc., and seeing what scenarios the data will agree with. Most of the body of global warming theory is based on computerized climate models called global circulation models or GCMs, for they are almost the only tools global warming researchers have. GCMs are difficult to make as making them properly involves a deep-rooted understanding of the way the atmosphere works and how its actions are interconnected with other planetary bodies, such as the oceans or the terrestrial biosphere. But our understanding of the inner workings of the atmosphere and the ways it relates to other planetary bodies is not very good. Renowned NASA climate modeler James Hansen, the man whose summer 1988 congressional testimony kicked off the climate change debate, states in the Proceedings of the National Academy of Sciences: “The forcings [outside factors] that drive long-term climate change are not known with an accuracy sufficient to define future climate changes.” One of the fundamental illustrations of chaos, the butterfly effect, displays the interconnectedness of the atmosphere system when it states that a butterfly fluttering through the air in China could cause rain in New York the following spring.
GCMs are made by formulating mathematical descriptions of the interrelationships between the atmosphere/ocean/biosphere/cryosphere system and conducting numerical experiments. They certainly are unable to form a mathematical description based on the kind of interconnections, or feedbacks, that the butterfly effect would suggest. Indeed, Michael Schlesinger, modeler at the University of Illinois, Urbana-Champaign, tells us that “in the climate system, there are 14 orders of magnitude, from the planetary scale–which is 40 million meters–down to the scale of one of the little aerosol particles on which water vapor can change phase to a liquid [cloud particle]–which is a fraction of a millionth of a millimeter.” Of these 14 orders of magnitude, only the two largest (the planetary scale and the scale of weather disturbances) can currently be included in models. Schlesinger notes that, to include the third order of magnitude (the scale of thunderstorms, at about 50 km resolution) a computer a thousand times faster would be necessary, “a teraflops machine that maybe we’ll have in 5 years.” Including all orders of magnitude would require 1036-1037 times more computing power (Kerr – Greenhouse Forecasting).
Because GCMs are so hard to make, often they account for the same processes differently; two models may have two different mathematical descriptions of what effect clouds have on warming, for example. Processes with a resolu
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