Climate Engineering: Worth the Risk?

By Ashley Chang, Genetics ’15

Researchers at the GEOMAR Helmhotltz Centre for Ocean Research Kiel are studying the long-term effects of “climate engineering” methods that could help to preserve the climate and protect from rising temperatures. This winter every part of the world except the eastern United States reported record breaking high temperatures. Although political agreements have been made to reducing greenhouse gas emissions, the effects may be too slow as levels of CO2 and other greenhouse gases continue to rise. This is especially important as populous countries, such as China and India, become increasingly industrialized and consequentially raise their greenhouse gas emissions. Previous studies done on alternative climate engineering options  have considered the climate under varying conditions and thus have not been comparable. In contrast, the study hosted at GEOMAR used the same basic Earth system and predicted changes for all of the possible solutions. They chose to test five common climate engineering techniques: the reduction of incoming solar radiation, afforestation of large desert areas in North Africa and Australia, and three techniques to increase oceanic carbon dioxide uptake. Afforestation is the establishment of a forest where there were previously no trees, in contrast to reforestation, which involves planting trees in areas that have been clear-cut.

Unfortunately, only the continuous reduction of solar radiation was successful at keeping temperatures from rising significantly. Suggested large-scale means of accomplishing this are atmospheric aerosols or mirrors in space. Other options, such as afforestation, actually led to higher temperatures because the Earth would become darker and could hold more heat. The researchers suggested that whether any of these methods are feasible could easily become insignificant if there is no political agreement. For example, in 50 years if the sun’s rays are no longer blocked, climate change would occur much more rapidly and with devastating consequences as organisms will not be able to adapt. Overall, research is not close enough to a solution for how to reverse climate change, and we are left with reducing our own greenhouse gas production.

Journal Reference:

David P. Keller, Ellias Y. Feng, Andreas Oschlies. Potential climate engineering effectiveness and side effects during a high carbon dioxide-emission scenario. Nature Communications, 2014; 5 DOI: 10.1038/ncomms4304

Photography Yuriy Kulik / Fotolia