Global streamflow and flood response to stratospheric aerosol geoengineering

摘要: Abstract. Flood risk is projected to increase under future warming climates due an enhanced hydrological cycle. Solar geoengineering known reduce precipitation and slow down the cycle may therefore be expected offset increased flood risk. We examine this hypothesis using streamflow river discharge responses Representative Concentration Pathway 4.5 (RCP4.5) Geoengineering Model Intercomparison Project (GeoMIP) G4 scenarios. Compared with RCP4.5, streamflow on western sides of Eurasia and North America G4, while eastern see a decrease. In Southern Hemisphere, northern parts landmasses have lower southern increases relative RCP4.5. We furthermore calculate changes in 30-, 50-, 100-year return periods relative historical (1960–1999) period RCP4.5 Similar spatial patterns are produced for each period, although those G4 closer values than RCP4.5. Hence, general, solar does appear reduce in most regions, but overall effects largely determined by this large-scale geographic pattern. Although stratospheric aerosol geoengineering ameliorates Amazon drying a weak increase soil moisture, decreased runoff leads an increased compared RCP4.5.