平特五不中

Dr.聽 Michael Winton joins us from the Geophysical Fluid Dynamics Laboratory of National Oceanic and Atmospheric Administration for his seminar titled聽Estimating and Using the Transient Climate Response. Refreshments will be served.

Abstract

We argue that the transient climate response (TCR) is the key sensitivity metric for determining the CO2 emissions compatible with the 2 degree global warming limit adopted by the UNFCCC. We make new best and upper-bound estimates of the TCR using an emergent relationship between the recent global warming trend and the TCR in the CMIP5 models. The spread between the best and upper-bound estimates is larger than for the CMIP5 models, a feature held in common with other estimates using recent observations. We develop a simple method for estimating the CO2 emissions compatible with a given warming. Allowable emissions are shown to vary more than inversely proportionally to TCR due to the effect of past CO2 emissions and future non-CO2 emissions. We use the method to evaluate a preliminary future global emissions estimate based on summing the national emissions submitted for the upcoming meeting of the UNFCCC.