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The blue line is the control, and for the orange line the SST in all land points (i.e. where CL>0 CL LSM>0.5) has been replaced by 321.35. The plots show SST, surface temperature, sensible and latent heat fluxes in this point. There is a dramatic heat flux during the 2nd timestep. Interestingly enough, the gridpoint next to this point doesn't show any response to an SST change:
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The thing that puzzles me is that the value of SST over land shouldn't play any role. There is no value for missing/undefined in GRIB, therefore there must be some value for the SST even over land in the initial conditions which is usually never updated during a simulation and constant over time. The IFS documentation Part IV Section 8.2.1 clearly states: "A mixture of land and water (ocean/inland water) tiles is not allowed, i.e. a grid box is either is either 100% land or 100% sea." Thus, any value of SST shouldn't be used anywhere in the surface scheme where CL>0 CL LSM>0.5. However, my tests that change SST over land points tell something else.
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