This blog aims to assess a process of geoengineering, specifically solar radiation management (SRM). SRM is the artificial use of aerosols, to increase Sun reflectivity away from the Earth, and decrease global temperatures (Keith et al 2010). The globe is expected to increase in temperatures due to increasing carbon dioxide levels. Hence, with the use of SRM there is more reflection of the sun away from the stratosphere and less heat reaches the Earth’s surface (similar to a volcano’s eruption) (Figure 1).
|Figure 1: Solar Radiation Management methods to reduce the Sun reflection|
Source: The Ecologist
The SRM aims to reduce temperature and hence reduce glacial ice melt and sea level rises, that may occur with increasing temperatures (Burns 2011). Applegate and Keller (2015) suggest that SRM process, will help reduce these impacts through assessing the Greenland Ice Sheet. If SRM is effective, this may help the tundra biome to be sustained and reduce environmental impacts. However, it is expected that this process will take place around 2025, according to the model and will need approximately a further decade for the SRM processes to be effective. Hence, this delay in the use of SRM procedures, will likely lead to further dramatic impacts. Applegate and Keller suggest that once the glacial ice melts, it is hard to restore it back to its initial conditions and thus the SRM impacts may not be as effective as anticipated.
As the artificial aerosols tend to be composed of sulphur it is likely that rain will be acidic. This may be problematic as it may contaminate freshwater ecosystems such as lakes and rivers and lead to a depletion of species such as fish as seen in Scandinavia (Pyatt 1987). A degradation of forests may occur through acid rain, such as in Germany due to the industrial revolution (Walgate 1983).
SRM may be more beneficial and effective, if the process takes place as soon as possible. However, there are high levels of uncertainty as it is a new process. Hence, it is very likely that acid rain may occur with SRM, creating further damage to Earth rather than repair.
Is it worth the risk undertaking SRM processes? Follow me next week to assess people’s thoughts on the matter; but for now, feel free to input your own thoughts.