Hysteresis of the El Niño-Southern Oscillation to CO2 forcing
Description
This is a carbon-removal dataset used to investigate the hysteresis of ENSO SST variability to CO2 forcing. It includes two experiments, namely, a present-day (PD) control and CO2 ramp-up and ramp-down experiments. The PD experiment is integrated for 900 years with a fixed CO2 concentration (1×CO2, 367 p.p.m.v.) in the present climate. The CO2 ramp-up and ramp-down experiment branches from the PD experiment at different phases of the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation to generate a total of 28 ensemble members. Each member is forced by the same time-varying CO2 forcing for 500 years, comprising a 1% increase per year in the CO2 concentration for 140 years until the concentration quadrupled (4×CO2, 1,468 p.p.m.v., ramp-up period); and a subsequent symmetric 1% decrease per year in CO2 concentration for another 140 years until it returned to the initial level (1×CO2, 367 p.p.m.v., ramp-down period), and a fixed CO2 concentration for the remaining 220 years (1×CO2, 367 p.p.m.v., restoring period).