Equilibrium climate sensitivity in light of observations over the warming hiatus
Artikel i vetenskaplig tidskrift, 2015

A key uncertainty in projecting future climate change is the magnitude of equilibrium climate sensitivity (ECS), that is, the eventual increase in global annual average surface temperature in response to a doubling of atmospheric CO2 concentration. The lower bound of the likely range for ECS given in the IPCC Fifth Assessment Report (AR5; refs 1,2) was revised downwards to 1.5 degrees C, from 2 degrees C in its previous report(3), mainly as an effect of considering observations over the warming hiatus-the period of slowdown of global average temperature increase since the early 2000s. Here we analyse how estimates of ECS change as observations accumulate over time and estimate the contribution of potential causes to the hiatus. We find that including observations over the hiatus reduces the most likely value for ECS from 2.8 degrees C to 2.5 degrees C, but that the lower bound of the 90% range remains stable around 2 degrees C. We also find that the hiatus is primarily attributable to El Nino/Southern Oscillation-related variability and reduced solar forcing.

Författare

Daniel Johansson

Chalmers, Energi och miljö, Fysisk resursteori

Brian O'Neill

National Center for Atmospheric Research

Claudia Tebaldi

National Center for Atmospheric Research

Olle Häggström

Göteborgs universitet

Chalmers, Matematiska vetenskaper, matematisk statistik

Nature Climate Change

1758-678X (ISSN) 1758-6798 (eISSN)

Vol. 5 5 449-453

Ämneskategorier

Meteorologi och atmosfärforskning

Miljövetenskap

DOI

10.1038/nclimate2573

Mer information

Skapat

2017-10-08