Why does RCP1.9 always fail to be solved in SSP2?

[wangyingying1227]

Hello, I have a question. Why does RCP1.9 always fail to be solved in SSP2? Increasing the number of model iterations and lowering the model accuracy have been tried

[wangyingying1227]

There are periods that model can't solve.

[Vapson]

I wonder if you have solved this problem?

[jayfuhrman]

Hi @wangyingying1227, @Vapson, which model periods are not solving? In SSP/SPA2, carbon pricing does not begin until 2040, which would likely make it infeasible to then return to 1.9 W/m2 under SSP2 technology and GDP growth assumptions which in turn inform constraints on negative emissions deployment. This was our finding for a SSP2-1.9 scenario without direct air capture available from our recent paper (in the supplementary information):

https://iopscience.iop.org/article/10.1088/1748-9326/ac2db0/meta