Climate Engineering

I'm sure that you are all aware of the problem of climate change and carbon dioxide in the atmosphere. Well since the 1960's, scientists have been trying to come up with a way to manipulate the Earth's environment and counteract climate change using geo-engineering. In October 2011, scientists began developing an array of techniques to reduce or offset climate change driven by greenhouse gases. Carbon dioxide removal (CDR) is the removal of carbon dioxide from the atmosphere by addressing the root cause of climate change and rising carbon dioxide concentrations. This method has low uncertainties and low risks. Solar radiation management (SRM) looks at reflecting a small amount of the Sun's light and heat back into space, quickly, reducing some of the effects of climate change. However, it may create other problems and doesn't address the impacts of carbon dioxide. It acts by increasing the albedo of the atmosphere by injecting sulphate aerosols into the stratosphere, reflecting the solar energy back into space, lowering the global temperature. A test was being undertaken by the Stratospheric Particle Injection for Climate Engineering (SPICE), with a balloon and a kilometre long hose, to spray water into the upper atmosphere, which would be a prelude to spraying climate cooling sulphate particles into the stratosphere. 10 to 20 giant balloons at a 20km altitude could release enough particles into the stratosphere, reducing the global temperature by 2 degrees centigrade. EcoNexus argued that this could have harmful impacts, and that questions need to be answered on the ethics and the impacts on biodiversity.

SPICE balloon (courtesy of the BBC)

In September 2013, a few more risks were pointed out. Although geo-engineering could be one way to cool down the Earth, or reduce carbon dioxide in the atmosphere, scientists know that these technologies are in the early stages of development. They have pointed out that manipulating the climate in one part of the world could have consequences elsewhere, and changing another country's weather is a war crime under the Geneva Convention from 1976. Lacing the stratosphere with sulphate aerosols could deplete the atmospheric ozone and could increase the risk of drought. It may also curtail the momentum for reducing carbon dioxide emissions, as it would take a lot of money and people may think that it means that they can carry on as they are. Geo-engineering would need an international agreement, and until that happens, temperatures will continue to rise and people will have to adapt.
Scientists have continued to work on this, and earlier this month, they made a new discovery. Attempts to reverse the impacts of global warming by injecting particles into the stratosphere could make matters worse. It could cut rainfall in the tropics by 30%, having devastating impacts on rainforests in South America and Asia. The scientists also found that as well as absorbing some of the heat from the Sun, the particles could absorb some of the heat energy that comes form the Earth's surface. It is clear that these technologies are still in their infancy, and more work needs to be done if we want to offset that damage cause by carbon dioxide.