ALBERT

Description: Limiting global warming to well below 2 °C is an imminent challenge for humanity. However even if this global target can be met, some regions are still likely to experience substantial warming relative to others. Using idealized global climate simulations we examine the potential of land management options in affecting regional climate, with a focus on crop albedo enhancement and irrigation (Climate-effective Land Management). The implementation is performed over all crop regions globally to provide an upper bound. We find that the implementation of both crop albedo enhancement and irrigation can reduce hot temperature extremes by more than 2 °C in North America, Eurasia and India over the 21 st century relative to a scenario without management application. The efficacy of crop albedo enhancement scales with the magnitude, where a cooling response exceeding 0.5 °C for hot temperature extremes was achieved with a large (i.e. ≥ 0.08) change in crop albedo. Regional differences were attributed to the surface energy balance response with temperature changes mostly explained by latent heat flux changes for irrigation and net shortwave radiation changes for crop albedo enhancement. However limitations do exist, where we identify warming over the winter months when climate-effective land management is temporarily suspended. This was associated with persistent cloud cover that enhances longwave warming. It cannot be confirmed if the magnitude of this feedback is reproducible in other climate models. Our results overall demonstrate that regional warming of hot extremes in our climate model can be partially mitigated when using an idealized treatment of Climate-effective Land Management.