Solar Radiation Management: Effects on Earth

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).

Thoughts:

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.

Geoengineering: An Introduction

Welcome to my blog! In summary, I am interested in assessing if geoengineering will help mitigate climate change impacts or if it will lead to further unresolved problems in the future. This will be assessed through academic reading on the topic, books, newspaper articles and videos that I may find interesting.  I look forward to your inputs and discussions on the topic.

Why geoengineering?

A few months ago, I stumbled across this youtube video.  When seeing this video I realised the Earth is 4.5 billion years old and humankind has been on the Earth for only 200,000 years.  Not a very long time when looking at the Earth’s age.  However, in this time period people have increased carbon dioxide levels greatly, causing the Earth to have high temperatures (IPCC 2012). With an increase in climatic changes it is expected that catastrophic phenomena will occur more frequently, such as earthquakes and tsunamis (IPCC 2012).  After watching this moving video it made me think about the destructiveness of human impacts on Earth.  Yet, the Earth will ‘survive’, however, how long will human kind survive?

Although the safe level of carbon dioxide in the atmosphere is 350ppm, according to NASA, levels have exceeded 400ppm (Figure 1).  The increased carbon dioxide levels have occurred from burning of fossil fuels since the 1850s (i.e. industrial revolution) and will continue to increase until drastic measures are taken. Hence, the change in the atmosphere has lead to many problems, such as glaciers shrinking, ecological patterns shifting and temperatures rising (NASA).  It is expected that problems will only get worse.

Figure 1: Carbon Dioxide in the atmosphere from 1960 to 2015
 Source: NOAA  

Ideally to stop further increases in carbon dioxide, all interactions with fossil fuels should stop immediately.  However, is this realistic? People and economies are too woven into their ‘luxurious’ lifestyles using amenities that burn fossil fuels, such as electricity and cars.  Furthermore, if all fossil fuel usage stopped, there would be a substantial decrease in agricultural production.  Most work would be undertaken manually and agricultural supply would be far less than the required demand, creating food security problems.  Hence, a realistic solution to reduce carbon dioxide at a fast rate, which may not interfere with our lifestyles, could be geoengineering.  

What is geoengineering? 

Geoengineering is the purposeful large-scale control of environmental procedures that influence the Earth's atmosphere with the aim to balance the impacts of global warming (Welch et al 2012).  It is divided into two main categories, carbon dioxide removal and solar radiation management.  However, there are high degrees of uncertainty if geoengineering is the correct step forward as it is a new and fairly unknown process.

Questions:

This blog aims to discuss the following questions:

• Is geoenengineering a viable process to mitigate climate change impacts?
• What geoengineering processes are more effective to reduce climate change impacts?
• What processes of geoengineering are more safe to use?

I look forward to hearing from you.