| In this master thesis a brief linear model was established through examining the quantitative relationship between global warming and radiative forcing change. In addition, the global annual mean temperature in the near 50 years was predicted using this model.In the preface, the global climate change after the industrial revolution was summarized, which indicated that golbal surface-troposphere system was warming remarkably during the past 40 years.In Chapter 1, a detailed thorough review on global warming was presented. First, the definition of radiative forcing was introduced, and its principles were summarized. Second, the global energy budget model was briefly described. The comprehensive review for factors (natural and human-generated) that might introduce global climate change, including solar irradiance, well-mixed greenhouse gases, land use change, ice melting and permafrost thaw, aerosol and other natural factors like volcanic eruptions, etc, leaded to the conclusion that 1) well-mixed greenhouse gases, ice melting and permafrost thaw would give positive radiative forcings; 2) land use change and aerosol would give negative radiative forcings; 3)solar irradiance carried a 11-year-periodicity change with little variety both in and between periodses; and 4) very little or uncertain radiative forcings in other natural factors and no detail was make out. At the end of this chapter, the consequences that may happen after global climate change were summarized.In chapter 2, research methods were described. In this research, factors that may cause global climate change were mainly taken in to consideration, such as solar irradiance, well-mixed greenhouse gases, planet albedo (or surface reflection properties of the earth), fuel consumption, aerosol and the earth's long wave radiation, etc. First the canonical official data were investigated, and then converted to 1880-relatived radiative forcings by different formulae. After all the forcings being summed up annually, net radiative forcings were obtained. A linear model was established by examining the quantitative relationship between global mean temperature and net radiative forcing.In chapter 3, the global mean tempeture change and the data of various factors that were mentioned in chapter 2 were analyzed, and graphs for each factor were ploted. Then graphs for radiative forcings were ploted accordingly. Through summing all the radiative forcings up, net annual radiative forcings were obtained and graphs for them were ploted. By examining the changes of global temperature and net radiative forcing between 1885 and 1955, a simplified linear model were established. Based on our model, 1 Wm-2 net radiative forcing would lead to 0.72℃increase of the global temperature.In chapter 4, we modified the model by comparing the recorded global mean temperature of 1956-2000 with the data predicted by our model. The modified model indicated that 1 wm-2 net radiative forcing would account for 0.67°C global warming.In chapter 5, future global mean temperature change was predicted by using the modified model. The mean value of future global temperature was simulated with the predicted changes of factors. The result indicated that in the future 50 years, the earth would warm up by 0.6℃.In chapter 6, the rationale of the model is discussed, and the pros and cons were proposed. Generally, if positive feedback is considered into this model, the global temperature would increase to a much more extreme extent in the future 50 years.
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