Climate & Environment

Solar Radiation Management (SRM)

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Definition

Solar radiation management refers to proposed large-scale interventions to reduce global temperatures by increasing Earth's reflectivity — most prominently stratospheric aerosol injection (releasing reflective particles into the upper atmosphere, mimicking volcanic cooling), marine cloud brightening and cirrus cloud thinning. Modelling suggests SRM could lower temperatures quickly and cheaply, but it would not stop ocean acidification, would alter regional climate and precipitation unevenly, and would require perpetual maintenance to avoid rapid rebound warming.

References

www.unep.orgBulk import source

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This reference provides supporting context for how “Solar Radiation Management (SRM)” is defined and used.

Overview

How it is used

The concept structures geoengineering governance debates (UNEP, Convention on Biological Diversity's de facto moratorium), research assessment programmes and discussions of solar geoengineering's distributive and security implications.

Why it matters

SRM is the contingency nobody wants and some fear will be needed; governing it before it is used may be among this century's hardest diplomatic tasks.