Optimal Control for the Process of Using Artificial Sulfate Aerosols for Mitigating Global Warming

Abstract

The optimal control problem for deliberate intervention in the Earth’s climate system with the aim of stabilizing the global surface temperature is considered. The deliberate action on the climate system is implemented via the controlled radiative disturbance created by artificial aerosols injected into the stratosphere. The controlled object is described by a two-component energy-balance model subject to radiative action caused by an increase in the concentration of greenhouse gases in the atmosphere. The human impact on the climate system is specified in accordance with Representative Concentration Pathway (RCP) scenarios, as well as with the scenario corresponding to a 1% increase in atmospheric carbon dioxide per year. The albedo of the artificial aerosol global layer represents the control variable. The optimal control and the corresponding phase trajectory of the climate system are obtained analytically using Pontryagin’s maximum principle. The approach discussed in this paper can be considered as a basis for developing scenarios for deliberate intervention in the climate system using various geoengineering methods.