Using simple energy balance equation- but adding feebacks in now!
1) Assume that the total feedback is ~1.5 W m-2 per °C. How much are temperature responses increased relative to the case without feedbacks?
2) Including the result from #1 in your model, calculate the global mean temperature change that would eventually result from the current anthropogenic forcing (2.3 W m-2 from homework #2).
3) Calculate the global mean temperature change resulting from the eventual forcing due to current CO2 emissions (which is ~7.4 W m-2 in 2500).
4) Calculate the forcing that would lead to a global mean temperature increase of 2°C.
5) Assuming CO2 emissions are linearly related to long-term CO2 RF, then use the results from questions 3 and 4 to calculate what fraction of current CO2 emissions would lead to a global mean temperature increase of 2°C.