Reflections on a meeting about space-based solar geoengineering




  • In the past Space technologies seemed more plausible than atmospheric SRM
  • Today it is the opposite: space based is rarely mentioned or explicitly excluded and dismissed
  • Only 2% of solar geoeng discuss space based techs in detail
  • Space enthuiasts don't seem to be interested ... which is weird since they talk about terra forming mars, moving industry into space etc.
  • They brought space entrepreneurs / writers / experts with counterparts in geoengineering for a meeting
  • Technology is several decades out
    • Simplest: constant position screen at L1
      • Capturing 1% of radiation = counteract 50% of current warming = screen Area of Egypt (likely many times that)
      • Gathering asteroid dust near the L1?
      • Many ideas but they all need a first level of screening / alls seem implausible
      • There are techno paths for 1% screen by end of century
    • low earth orbit not practical: debris / flickering
  • Not an alternative to emissions reductions
  • Not a plausible short or mid term solution, but does come with advantages
    • More even cooling
    • Less governance issues?
    • ...