Based on the IAP RAS climate model (CM), an estimation of geoengineering impact on characteristics of climate and carbon cycle is performed. In the model, geoengineering is applied for 2020-2070 to mitigate climate warming developing under aggressive anthropogenic scenario RCP 8.5. Assuming that horizontal distribution of stratospheric sulphates is homogeneous, complete mitigation of this warming suppresses precipitation and is accompanied by regional anomalies of temperature. Geoengineering impact on budget of short-wave radiation at the surface and fraction of diffuse radiation in this budget depends strongly on season. Geoengineering mitigation suppresses gross primary production of terrestrial vegetation and respective carbon stock, especially in Siberian boreal forest. In this, total terrestrial gross primary production during 2060-2070 is diminished by 17 PgCЧr-1 and total carbon stock in terrestrial vegetation is reduced by 33 PgC. At the same time, mitigation of globally averaged warming leads to increased rather than to depleted soil carbon stock in the 21st century. Differences in total soil carbon stock between the simulations with and without geoengineering may be as large as 97 PgC during this century. This leads to the slow-down of CO2 build up in the atmosphere. This slow-down amounts 52 ppmv in the end of the 21st century. However, the latter does not affect markedly climatic efficiency of geoengineering.
geoengineering, stratospheric aerosols, carbon cycle, climate, IAP RAS CM