UKESM1 simulations in support of the CS-N0W programme

The UK Earth System Model (UKESM1) has been used to produce two simulations for the Climate Services for a Net Zero Resilient World (CS-N0W) research programme. The first simulation ("no overshoot" or NO) was designed to fix global-mean annual-mean surface temperature to 1.5C above pre-Industrial levels from 2010-2100, and the second simulation ("very high overshoot" or VHO) was a scenario where global-mean annual-mean surface temperature was allowed to rise above 1.5C during the century but return to 1.5C by 2100. Four ensemble members were run for each scenario.

These are based on the UKESM1-0-LL model. Forcings followed the SSP2-4.5 Shared Socio-economic Pathway, except for chemistry and aerosol emissions which followed SSP1-1.9. CO2 and N2O concentrations were calculated used the TIMES Integrated Assessment Model at University College London (TIAM-UCL) model, which was also used to calculated CH4 for the NO simulation. CH4 in the VHO simuation used SSP1-1.9.