write a short note about AGW
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theory has been proposed that human activity over about the last 150 years has caused a significant rise in Earth’s average temperature. The mechanism claimed is based on an increased greenhouse effect caused by anthropogenic increases in CO2 from burning of fossil fuels, deforestation, cement manufacture, and also from increases in CH4 from farm animals and other causes. The present versions of the theory also include a positive feedback effect due to the increased temperature causing an increase in water vapor, which amplifies the effect. The combined result are used to claim that unless the anthropogenic increases of CO2 are slowed down or even made to decrease, there will be a continuing rapid increase in global temperature, massive melting of ice caps, flooding, pestilence, etc.
In order to support a theory, specific predictions need to be made that are based on the claims of the theory, and the predictions then need to happen. While the occurrence of the predicted events is not proof positive of a theory, they increase the believability of the claims. However, if the predictions are not observed, this tends to indicate the theory is flawed or even wrong. Some predictions are absolute in nature. Einstein’s prediction of the bending of light by the Sun is such a case. It either would or would not bend, and this was considered a critical test of the validity of his theory of general relativity. It did bend the predicted amount, and supported his theory.
Many predictions however are less easily supported. For example weather forecasting often does a good job in the very short term but over increasing time does a poor job. This is due to the complexity of the numerous nonlinear components. This complexity has been described in chaos theory by what is called the butterfly effect. Any effect that depends on numerous factors, some of which are nonlinear in effect, is nearly impossible to use to make long-range predictions. However, for some reason, the present predictions of “Climate Change” are considered by the AGW supporters to be more reliable than even short-term weather forecasting. While some overall trends can be reasonably made based on looking at past historical trends, and some computational models can suggest some suggested trends due to specific forcing factors, nevertheless, the long term predicted result has not been shown to be valid. Like any respectable theory, specific predictions need to be made, and then shown to happen, before the AGW models can have any claim to reasonable validity.
The AGW computational models do make several specific predictions. Since the time scale for checking the result of the predictions is small, and since local weather can vary enough on the short time scale to confuse the longer time scale prediction, allowances for these shorter lasting events have to be made when examining predictions. Nevertheless, if the actual data results do not significantly support the theory, it must be reconsidered or even rejected as it stands.
The main predictions from the AGW models are:
The average Earth’s temperature will increase at a rate of 0.20C to 0.60C per decade at least to 2100, and will continue to climb after that if the CO2continues to be produced by human activity at current predicted rates.
The increasing temperature will cause increased water evaporation, which is the cause for the positive feedback needed to reach the high temperatures.
The temperature at lower latitudes (especially tropical regions) will increase more in the lower Troposphere at moderate altitudes than near the surface.
The greatest near surface temperature increases will occur at the higher latitudes.
The increasing temperature at higher latitudes will cause significant Antarctic and Greenland ice melt. These combined with ocean expansion due to warming will cause significant ocean rise and flooding.
A temperature drop in the lower Stratosphere will accompany the temperature increase near the surface. The shape of the trend down in the Stratosphere should be close to a mirror reflection of the near surface trend up.
The present CO2 level is high and increasing
In order to support a theory, specific predictions need to be made that are based on the claims of the theory, and the predictions then need to happen. While the occurrence of the predicted events is not proof positive of a theory, they increase the believability of the claims. However, if the predictions are not observed, this tends to indicate the theory is flawed or even wrong. Some predictions are absolute in nature. Einstein’s prediction of the bending of light by the Sun is such a case. It either would or would not bend, and this was considered a critical test of the validity of his theory of general relativity. It did bend the predicted amount, and supported his theory.
Many predictions however are less easily supported. For example weather forecasting often does a good job in the very short term but over increasing time does a poor job. This is due to the complexity of the numerous nonlinear components. This complexity has been described in chaos theory by what is called the butterfly effect. Any effect that depends on numerous factors, some of which are nonlinear in effect, is nearly impossible to use to make long-range predictions. However, for some reason, the present predictions of “Climate Change” are considered by the AGW supporters to be more reliable than even short-term weather forecasting. While some overall trends can be reasonably made based on looking at past historical trends, and some computational models can suggest some suggested trends due to specific forcing factors, nevertheless, the long term predicted result has not been shown to be valid. Like any respectable theory, specific predictions need to be made, and then shown to happen, before the AGW models can have any claim to reasonable validity.
The AGW computational models do make several specific predictions. Since the time scale for checking the result of the predictions is small, and since local weather can vary enough on the short time scale to confuse the longer time scale prediction, allowances for these shorter lasting events have to be made when examining predictions. Nevertheless, if the actual data results do not significantly support the theory, it must be reconsidered or even rejected as it stands.
The main predictions from the AGW models are:
The average Earth’s temperature will increase at a rate of 0.20C to 0.60C per decade at least to 2100, and will continue to climb after that if the CO2continues to be produced by human activity at current predicted rates.
The increasing temperature will cause increased water evaporation, which is the cause for the positive feedback needed to reach the high temperatures.
The temperature at lower latitudes (especially tropical regions) will increase more in the lower Troposphere at moderate altitudes than near the surface.
The greatest near surface temperature increases will occur at the higher latitudes.
The increasing temperature at higher latitudes will cause significant Antarctic and Greenland ice melt. These combined with ocean expansion due to warming will cause significant ocean rise and flooding.
A temperature drop in the lower Stratosphere will accompany the temperature increase near the surface. The shape of the trend down in the Stratosphere should be close to a mirror reflection of the near surface trend up.
The present CO2 level is high and increasing
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