摘要
Continuous emissions of anthropogenic greenhouse gases(GHGs)and aerosols in the last 160 years have resulted in an increasing trend of global mean surface temperatures(GMSTs).Due to interactions with natural variability,rates of the combined anthropogenically and naturally induced warming trends are characterized by significant slowdowns and speedups on decadal timescales.Here,by analyzing observed and model-simulated data,we investigate how the duration of these episodes will change with different strengths of GHG and aerosol forcing.We found that the duration of warming slowdowns can be more than 30 yr with a slower rate of anthropogenic emissions but would shorten to about 5 yr with a higher one.This duration reduction depends on both the magnitude of the climate response to anthropogenic forcing and the strength of the internal variability.Moreover,the warming slowdowns can still occur even towards the end of this century under high emissions scenarios but with significantly shortened duration.
基金
the National Key Research and Development Program of China(2016YFA0602100 and 2018YFE0109600)
Regional and Global Model Analysis(RGMA)component of the Earth and Environmental System Modeling Program of the U.S.Department of Energy’s Office of Biological&Environmental Research(BER)via National Science Foundation(IA 1844590)
National Center for Atmospheric Research,which is a major facility sponsored by the National Science Foundation under Cooperative Agreement(1852977)。