Tuesday, March 11, 2014

Geoengineering Ineffective Against Climate Change, Could Make Worse

By Charles Q. Choi, Live Science Contributor, Live Science

Current schemes to minimize the havoc caused by global warming by purposefully manipulating Earth's climate are likely to either be relatively useless or actually make things worse, researchers say in a new study.
The dramatic increase in carbon dioxide levels in the atmosphere since the Industrial Revolution is expected to cause rising global sea levels, more-extreme weather and other disruptions to regional and local climates. Carbon dioxide is a greenhouse gas that traps heat, so as levels of the gas rise, the planet overall warms.
In addition to efforts to reduce carbon dioxide emissions, some have suggested artificially manipulating the world's climate in a last-ditch effort to prevent catastrophic climate change. These strategies, considered radical in some circles, are known as geoengineering or climate engineering.
Many scientists have investigated and questioned how effective individual geoengineering methods could be. However, there have been few attempts to compare and contrast the various methods, which range from fertilizing the ocean so that marine organisms suck up excess carbon dioxide to shooting aerosols into the atmosphere to reflect some of the sun's incoming rays back into space. [8 Ways Global Warming is Already Changing the World]
Now, researchers using a 3D computer model of the Earth have tested the potential benefits and drawbacks of five different geoengineering technologies.
Will it work?
The scientists found that even when several technologies were combined, geoengineering would be unable to prevent average surface temperatures from rising more than 3.6 degrees Fahrenheit (2 degrees Celsius) above current temperatures by the year 2100. This is, the current limit that international negotiations are focused on. They were unable to do so even when each technology was deployed continuously and at scales as large as currently deemed possible. Read More