我在读这在realclimate.org上。在下面是我的问题。物理可以告诉你公司的辐射强迫<子> 2 < /订阅>,这是美元\小\ mathsf {5.35 ln (Cnew / Cpreindustrial)} $。这告诉你多少辐射强迫期望增加有限公司<子> 2 > < / sub(= $ \小\ mathsf {C_{新})}$在工业化前水平(C工业化前的,通常是280 ppm)。辐射强迫的这个公式提供了一个明确的答案。但是…有一个问题,然后出现变暖是什么与这个特定级别的辐射强迫。这个* *是一个实证问题,看着过去的波动的CO 2 <子> < /订阅>和温度有关。这是气候敏感性。有大量的研究,现在接受范围为1.5 - -4.5°C。 But there reason there is some disagreement about this is that it is an empirical question, not so much a physics one, right? Here's the realclimate piece: > Blockquote As the name suggests, climate sensitivity is an estimate of how sensitive the climate is to an increase in a radiative forcing. The climate sensitivity value tells us how much the planet will warm or cool in response to a given radiative forcing change. As you might guess, the temperature change is proportional to the change in the amount of energy reaching the Earth's surface (the radiative forcing), and the climate sensitivity is the coefficient of proportionality: dT = λ*dF Where 'dT' is the change in the Earth's average surface temperature, 'λ' is the climate sensitivity, usually with units in Kelvin or degrees Celsius per Watts per square meter (°C/[W/m2]), and 'dF' is the radiative forcing. So now to calculate the change in temperature, we just need to know the climate sensitivity. Studies have given a possible range of values of 2-4.5 °C warming for a doubling of CO2 (IPCC 2007). Using these values it's a simple task to put the climate sensitivity into the units we need, using the formulas above: λ = dT/dF = dT/(5.35 * ln[2])= [2 to 4.5 °C]/3.7 = 0.54 to 1.2 °C/(W/m2>/sup>) Using this range of possible climate sensitivity values, we can plug λ into the formulas above and calculate the expected temperature change. The atmospheric CO2 concentration as of 2010 is about 390 ppmv. This gives us the value for 'C', and for 'Co' we'll use the pre-industrial value of 280 ppmv. dT = λ*dF = λ * 5.35 * ln(390/280) = 1.8 * λ Plugging in our possible climate sensitivity values, this gives us an expected surface temperature change of about 1–2.2 °C of global warming, with a most likely value of 1.4 °C. However, this tells us the equilibrium temperature. In reality it takes a long time to heat up the oceans due to their thermal inertia. For this reason there is currently a planetary energy imbalance, and the surface has only warmed about 0.8 °C. In other words, even if we were to immediately stop adding CO2 to the atmosphere, the planet would warm another ~0.6 °C until it reached this new equilibrium state (confirmed by Hansen 2005). This is referred to as the 'warming in the pipeline'.
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