Sensitivity of simulated climate to latitudinal distribution of solar insolation reduction in SRM geoengineering methods

A. Modak, G. Bala
2013 Atmospheric Chemistry and Physics Discussions  
Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion Abstract Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion Abstract Solar radiation management (SRM) geoengineering has been proposed as a potential option to counteract climate change. We perform a set of idealized geoengineering simulations to understand the global hydrological implications
more » ... ogical implications of varying the latitudinal distribution of solar insolation reduction in SRM methods. We find that for a fixed to-5 tal mass of sulfate aerosols (12.6 Mt of SO 4 ), relative to a uniform distribution which mitigates changes in global mean temperature, global mean radiative forcing is larger when aerosol concentration is maximum at the poles leading to a warmer global mean climate and consequently an intensified hydrological cycle. Opposite changes are simulated when aerosol concentration is maximized in the tropics. We obtain a range of 10 1 K in global mean temperature and 3 % in precipitation changes by varying the distribution pattern: this range is about 50 % of the climate change from a doubling of CO 2 . Hence, our study demonstrates that a range of global mean climate states, determined by the global mean radiative forcing, are possible for a fixed total amount of aerosols but with differing latitudinal distribution, highlighting the need for a careful evaluation of 15 SRM proposals. 20 2007). Their increase has the potential to cause long term climate change by altering the planetary radiation budget. To moderate future climate change and its impacts, several geoengineering proposals have been made recently. By definition, geoengineering is an intentional large-scale manipulation of the environment, particularly intended to counteract the undesired consequences of anthropogenic climate change 25 Abstract Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion
doi:10.5194/acpd-13-25387-2013 fatcat:bi5qllnrnvbzfa6m4ynt77gfwi