GSL colleagues found a drift in SST in coupled forecasts done at C96 resolutions.
We identified this to be related to convection/cloud/radiation interaction - when suspended convective clouds are passed to the Xu-Randall cloud fraction and/or optical depth calculation we get this drift in SSTs in coupled simulations. The problem does not occur at C192, C384, C768 and C1152.
Solution
Add a namelist flag to control in which application this convection/cloud/radiation coupling should occur.
Description
GSL colleagues found a drift in SST in coupled forecasts done at C96 resolutions.
We identified this to be related to convection/cloud/radiation interaction - when suspended convective clouds are passed to the Xu-Randall cloud fraction and/or optical depth calculation we get this drift in SSTs in coupled simulations. The problem does not occur at C192, C384, C768 and C1152.
Solution
Add a namelist flag to control in which application this convection/cloud/radiation coupling should occur.