(disclaimer: I work in a climate group) Please do not do this :). Deserts are great for shedding heat into space (highly reflective in the visible, highly emi

(disclaimer: I work in a climate group) Please do not do this :). Deserts are great for shedding heat into space (highly reflective in the visible, highly emissive in the infrared, low moisture in the atmosphere). We had a theory (not yet published, so take it with a grain of salt) that desertification might buffer the radiative forcing effects of CO2. Unfortunately, when we analyzed the last 20 years of satellite data, the opposite is happening--people have been watering the desert like crazy, leading to a net reduction on the order of ~100-200,000km^2.