As the impacts of climate change continue to mount up, there is increasing interest in radical intervention measures designed to keep a lid on rising global temperatures. Such measures are fraught with potential dangers and unintended consequences but there is no guarantee that one or another of them might still be attempted in the future. Increasing international interest in geoengineering as a potential strategy for mitigating climate change has created a pressing need to consider its impact before any potentially irreversible actions are taken.
The Natural Environment Research Council in the UK is funding four research projects aimed at understanding the potential consequences of solar radiation modification (SRM) being deployed in the real world.
SRM consists of methods to reflect some of the Sun’s radiation back into space instead of allowing it to reach and warm the earth.
One approach is stratospheric aerosol intervention in which particles such as sulfates are introduced into the upper atmosphere to reflect sunlight thereby producing a dimming effect. The idea is to mimic the effects of large volcanic eruptions, which naturally send sulfates into the atmosphere.
A second approach is marine cloud brightening, which increases the reflectivity of clouds over the ocean by spraying very small droplets of sea water into the air. The fine particles of sea salt enhance cloud condensation nuclei, producing more cloud droplets and making clouds more reflective.
The research aims to deliver independent risk analyses to inform policymakers about the potential environmental impacts of SRM.
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Scientists to model the impact of controlling Earth’s temperature by reflecting solar radiation
Photo, posted May 6, 2009, courtesy of Denys Zadorozhnyi via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio
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