Abstracts Earth and Environmental Sciences

Trajectory Optimization of a Planetary Sunshade

by Filippo (author) Oggionni

A planetary sunshade is a large, reflecting disk built to shield the Earth from a small fraction of solar irradiance, partly compensating global warming caused by greenhouse gas emissions. As a specific form of solar geoengineering, the sunshade is an emergency solution that would be implemented to prevent catastrophic climate change, while working towards the net-zero emission goal. In this paper, a dynamic sunshade is proposed. Such a system is capable of not only reducing the global mean surface temperature anomaly, but also minimizing regional climate changes by tailoring the sunshade's motion according to climate requirements. A sunshade orbiting in the vicinity of the Sun-Earth L1 point is able to reduce the global mean surface temperature from 16.39°C (scenario with 680 ppm of atmospheric CO2) to 14.13°C until equilibrium is reached. It also reduces the polar mean surface temperature by more than 2°C with respect to a scenario without sunshade. Aerospace Engineering