Various geoengineering schemes show promise of reducing the impact of global climate change, but carry risks and limitations as well, according to a first-ever comprehensive assessment by researchers at the University of East Anglia.

Among the researchers’ findings:

• Enhancing carbon sinks around the globe could help bring down carbon dioxide levels, but only if done in conjunction with aggressive emissions mitigation … and not before 2100;
• Seeding the oceans with phosphorus shows greater long-term carbon sequestration potential than iron- or nitrogen-seeding schemes;
• Using space sunshades or pumping aerosols into the upper atmosphere have the greatest potential to dial down global warming by mid-century … but carry the greatest risks as well;
• Carbon sequestration by new forest growth or the use of bio-char could work more quickly to reduce global warming than could any ocean fertilisation strategy.

“The realisation that existing efforts to mitigate the effects of human-induced climate change are proving wholly ineffectual has fuelled a resurgence of interest in geoengineering,” said Tim Lenton, the study’s lead author. “We found that some geoengineering options could usefully complement mitigation, and together they could cool the climate, but geoengineering alone cannot solve the climate problem.”

Hmmm, and considering we’re not doing well at either just yet — mitigation or geoengineering — what’s that say for the state of the climate in years to come? Not much good, it seems.

Tags: geoengineering, global warming