Space-based Mitigation of Global Warming with a Planetary Sunshade - Limit global warming to 1.5º and reduce the risks from climate tipping points
- Paper ID
75031
- author
- company
Planetary Sunshade Foundation; Institute of Space Systems, University of Stuttgart; DLR (German Aerospace Center)
- country
Germany
- year
2023
- abstract
{\bf The climate crisis is now and getting worse fast: } \begin{itemize}\item The trajectory of emissions under best-case scenarios still points toward unacceptable warming, with unknown tipping points and removing gigatons of carbon from the atmosphere is a massive project. \end{itemize} \begin{itemize}\item Probably by 2030 the world will cross 1.5º of global warming \end{itemize} These points are {\bf uncontroversial climate science}, and they lead us to the question: What would space-based mitigation of global warming look like? Here we present the best {\bf technical and climate science understanding} of the problem. \begin{itemize}\item The energy imbalance caused by greenhouse gas emissions are known, and commonly measured as a watts per square meter effect. \end{itemize} \begin{itemize}\item Science analysis shows that a certain sized reflector in space, stationed at the Sun Earth Lagrange 1 point, would limit watts per square meter reaching the earth at a predictable rate, thus reducing global warming.\end{itemize} \begin{itemize}\item Technical concepts have been analyzed showing the feasibility of a planetary sunshade, a rough technical roadmap is defined, and overall costs are to be analyzed in detail.\end{itemize} \begin{itemize}\item The overall CO2 equivalent life cycle emissions of the Planetary Sunshade need to be minimized by using a green launch system and producing most of the material outside the Earth biosphere. Limiting warming to 1.5º eliminates substantial climate destruction and risk of tipping points\end{itemize} {\bf What should governments do as they learn about the possible solution of a space-based Sunshade?} \begin{itemize}\item From a climate political standpoint, global thinking is changing fast to even consider interventions such as stratospheric aerosol injection. These conversations should be informed by our best understanding of the Sunshade option. \end{itemize} \begin{itemize}\item From a space policy standpoint we recommend pushing for active climate protection with a Sunshade; just doing climate crisis observation from space will not be enough.\end{itemize} \begin{itemize}\item We can manage climate overshoot risks and keep temperatures at 1.5º while we transition to a zero-carbon economy and remove gigatons of GHGs from the atmosphere. \end{itemize} While preventing the earth from crossing 1.5º is not possible by 2030, a sunshade could be constructed {\bf reducing time of overshoot before then returning to globally-agreed upon safer temperatures}. We will present the technological roadmap necessary to achieve the Paris Temperature Goal of 1.5º global warming and the Montreal Convention on International Trade in Endangered Species of Wild Fauna and Flora.