In the tropics the tropopause is much higher in altitude than in temperate regions. The reason is for this is that warm ocean surfaces cool by evaporation moving latent heat upwards where it heats the upper atmosphere through condensation. The lapse rate moves towards the moist lapse rate. The tropopause is where the lapse rate peters out because radiation from GHGs to space dominates over convection. The tropopause is much higher in the tropics because there is so much water vapour in the atmosphere that radiation can only dominate where H2O wavelengths are no longer opaque. Despite this the temperature at these heights is not less than in temperate zones and the radiation loss is significant. This shows how the troposphere lapse rate and height is defined by greenhouse gas concentrations. If you add more water vapour to the atmosphere the troposphere increases in height. This is a negative feedback because more H2O does not lead to enhanced surface warming. On the contrary surface temperatures are stabilised by evaporation

What then happens if you add more CO2 ? Essentially the same negative feedback must occur. The effective height for CO2 radiative cooling to space increases to an initially colder level so leading to a slight increase in forcing. This slight forcing at the surface must also lead to more evaporation from the ocean reducing the lapse rate and thereby increasing the temperature of the effective height for CO2 radiation to space. The result is a negative feedback counteracting the original CO2 forcing.

This same effect happens every day in the tropics as solar radiation increases around midday then so too does evaporation. This is a strong negative feedback keeping ocean temperatures below ~30 deg.C . Exactly the same effect must occur for CO2.

I have been away from the UK for 5 weeks in Australia and Vietnam. Even Darwin ocean temperatures are below 30c while the air approaches 100% relative humidity and 38 C during midday. It then rains most days cooling the surface. Extreme temperatures only occur in deserts where there are no evaporation sources. Otherwise the oceans stabilise temperatures on Earth.

Scary 5.5 meter crocodile on the Adelaide river just outside Darwin. Keeping cool for the last 50 million years!

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