Is the climate response to CO2emissions path dependent?

摘要: [1] Recent studies with coupled climate-carbon cycle models suggest that global mean temperature change is proportional to cumulative CO2 emissions, independent of the timing those emissions. This finding has prompted suggestion climate stabilization targets, such as 2°C target adopted by Copenhagen Accord, can be expressed in terms Here we examine simulated response a range and regional variables same emissions (2500 PgC) released along different pathways using complex Earth system model. We find most surface largely pathway once cease, exception timescales centuries, ocean heat content thermosteric sea level rise. Peak responses many variables, temperature, precipitation ice, are also pathway, except for scenarios overshoot which require net removal from atmosphere. By contrast, peak atmospheric pH found dependent on pathway. conclude CO2mitigation framework based well suited limiting changes impact-relevant but less effective avoiding impacts directly associated CO2, whose rate