Climate Change Geoengineering Could Cause Droughts

A startling new report highlights how geoengineering technologies – designed to intentionally alter physical and/or biological elements of the Earth system – could actually heighten the chances of droughts occurring. 

The report appears in the current edition of the journal Science, and was co-authored by Gabriele Hegerl and Susan Solomon, representing Edinburgh University and (Colorado-based) NOAA – the National Oceanic and Atmospheric Administration – respectively.

Types of Geoengineering

Among the types of geoengineering proposed are ones involving vast mirrors that would redirect incoming solar radiation back towards the sun.  These, said the researchers, could trigger substantial weather pattern shifts like decreasing rainfall amounts.  On this basis, they called for rainfall assessments to be carried out in advance of any real progress being made towards developing geoengineering technologies, highlighting how: “if geo-engineering studies focus too heavily on warming, critical risks associated with such possible "cures" will not be evaluated appropriately.”

Geoengineering Climate Change

Hegerl and Solomon contested that there is more to global warming that simply higher temperatures, and transferred this argument across to idea of geoengineering climate change.  In doing this, they drew attention to cases of volcanic eruptions which, when they thrust dust into the air, stop solar radiation from being able to reach ground level, but which also influence rainfall significantly.  18 years ago, Mount Pinatubo erupted, and this prompted a drop in temperatures around the world, while drought levels went the other way. 

By comparing weather data for the period 1901-1999 with greenhouse gas emission data and a list of recent eruptions, date-by-date, Hegerl and Solomon discovered that there was an associable link between emissions and precipitation once a volcano had emitted its contents.  During the initial few weeks after the event, they said, levels of rainfall rose moderately, but soon fell way below their original level, and they added that the majority of modern-day climate forecasters didn’t put rainfall, emissions and eruptions into the
foreground as much as they should.

Geo-engineering, therefore, could generate depleted levels of localised rainfall and this, in turn, could put groups of people into conflict over the rights to water.

“Optimism about a geo-engineered 'easy way out' should be tempered by examination of currently observed climate changes”, the scientists warned, in conclusion.

See also:

Approval for Climate Change Geoengineering Research