New climate model promises to help avoid dangerous global warming

A new international study involving ANU has designed a new and simpler climate model that gives authorities a more precise picture of how humanity is tracking to avoid dangerous global warming this century. The Paris Climate Agreement set targets to restrict the rise in global temperatures to two degrees Celsius or less above pre-industrial levels by reducing carbon emissions. Co-researcher Professor Eelco Rohling from ANU said the uncertainties in climate models used by scientists today were too large to develop future carbon budgets that meet specific warming targets. "There is significant uncertainty in projecting the amount of carbon that can be emitted, in part due to the limited number of Earth system model simulations and their discrepancies with present-day observations," said Professor Rohling from the ANU Research School of Earth Sciences. "Our model narrows the uncertainty in global warming projections and reduces the range in equilibrium sensitivity of global temperatures to emissions." Professor Rohling said a warming target of 1.5 degrees above the pre-industrial level would require the total emitted carbon from the start of last year to be less than 195-205 petagrams of carbon. A petagram is one billion metric tonnes. "The two degree target is only likely if the emitted carbon remains less than 395 to 455 petagrams of carbon," Professor Rohling said.