Measures to control global warming other than Reduction in Carbon Emission

• The Paris Conference last year primarily discussed plans to reduce carbon emissions, which is understandable as this is the most immediate item for action. But other measures for dealing with global warming, in particular climate engineering, may soon acquire more importance.
• As nations struggle to reduce emissions even further, alternative solutions using engineering innovations will increasingly gain currency.

Measures:
Carbon capture and storage (CCS):
In this measure, some of the carbon dioxide being emitted by coal-fired power stations is recaptured by physically sucking it in and transporting it elsewhere to be sequestered underground. The first 115 MW CCS retrofitted coal power plant commenced operation at Boundary Dam in Canada in 2014. The carbon dioxide captured there is transported and pumped into nearby oilfields for enhanced oil recovery. This has reduced its carbon dioxide emission by one million tonne each year.
Increase forest cover:
It will absorb some of the unwanted carbon dioxide.
Solar radiation management (SRM)
Here the plan is to reduce global warming by cutting down the heat absorbed by our planet from the sun.
Stratospheric aerosol injection (SAI):
SAI, the boldest and also the most risky of climate engineering interventions, involves spraying into the stratosphere fine, light-coloured particles designed to reflect back part of the solar radiation before it reaches and warms the earth. SAI proponents claim that this could bring down the global temperature by as much as 1°C — a substantial amount in the climate change context. This is neither science fiction nor fantasy. Much preliminary research has already been done on this technique and reviewed in major journals. The optimal gases for injection, such as sulphur dioxide (SO{-2}), can be produced in abundance. Furthermore, just a few airplanes specially redesigned for the purpose may suffice for injecting the required aerosol into the stratosphere. There are also precedents from nature. The 1991 volcanic eruption of Mount Pinatubo in the Philippines injected 20 megatonnes of SO{-2}into the stratosphere, cooling the globe significantly for a couple of years. But SAI also has the potential for disastrous side effects, crossing national boundaries. The Pinatubo volcanic eruption is also said to have reduced precipitation, soil moisture, and river flow in many regions. Injection of sulphur compounds into the stratosphere is likely to increase acid deposition on the ground and also contribute to ozone layer depletion. Apart from such “known unknowns”, there could also be, to use the catchphrase, the “unknown unknowns”.SAI research is still at a theoretical and laboratory level.
Analysis:

• As climate change worsens, some coastlands could go underwater and other regions could suffer extreme heat and severe droughts causing massive human suffering. Under such pressure, and in the absence of international regulatory regimes, the affected nation, even a small developing one, may well resort to using whatever SAI technology is available by then in the international market. In their desperation, possible harmful effects on other countries may not weigh heavily on their decision-making. Meanwhile, just the fear of possible adverse side effects could lead other nations to take preventive action against the “perpetrator”. Nations have gone to war for less.
• One simple way to deal with this problem is to just ban further research in these fields. In fact, some climate scientists have already suggested this. They also fear that even the possibility of SRM interventions may undermine efforts to reduce carbon emissions. But a blanket ban on SRM would be unwise and difficult to implement. Technology, benign or malevolent, has a way of continuing to advance. Besides, banning all SRM research will amount to throwing the baby out with the bathwater. The goal of SRM is to mitigate damage done by carbon emissions. If there is some chance of it succeeding safely, it would be unwise to abandon it at this stage. Abandonment would also leave SRM technologies dangling midway, insufficiently tested or refined. That may nevertheless not deter some desperate climate change-afflicted nation from deploying it, leading to disaster.
• It is only through continuation of responsible research in climate engineering, done under proper regulatory oversight, that the limitations and risks of such interventions can be fully understood and provide the basis for informed decision-making. That will call for international governance mechanisms for overseeing the research and development and possible deployment of climate engineering techniques. This will take years to negotiate and set up. Criteria for permissible work will have to be developed, along with expertise for verification of compliance.
• While active climate engineering researchers have already been conscientiously worrying about these issues, it is not too early for the rest of us to start thinking about it.
   

By: Vishal