Context: Geoengineering has steadily shifted over the last few decades from the margins towards the mainstream of climate action discourse.
About

• Climate engineering aka geoengineering is the deliberate and large-scale intervention in the Earth’s climate system, usually with the aim of mitigating the adverse effects of global warming.
• It is a deliberate, large-scale intervention carried out in the Earth’s natural systems to reverse the impacts of climate change.
• Its techniques fall primarily under three categories: Solar radiation management (SRM), carbon dioxide removal (CDR) and weather modification.
• Solar radiation management refers to offsetting the warming effect of greenhouse gases by reflecting more solar radiation (sunlight) back into space.
• Carbon dioxide removal refers to removing carbon dioxide gas (CO2) from the atmosphere and sequestering it for long periods of time.

What are the specificities of geoengineering?
Specific technologies include

• Solar geoengineering or ‘dimming the sun’ by spraying sulfates into the air to reflect sunlight back into space;
• Ocean fertilization or the dumping of iron or urea to stimulate phytoplankton growth to absorb more carbon;
• Cloud brightening or spraying saltwater to make clouds more reflective and more.

CDR technologies being proposed as a means to achieve ‘net zero’ emissions by mid-century involve deliberate intervention in the natural carbon cycle:

• Carbon capture and storage (CCS), direct air capture (DAC) and
• Bioenergy with carbon capture and storage (BECCS)
• India and Geo-engineering

We had experiments such as LOHAFEX (an ocean iron fertilization experiment to see if iron can cause algal bloom and trap carbon dioxide from the atmosphere).

• LOHAFEX was an ocean iron fertilization experiment jointly planned by the Council of Scientific and Industrial Research (CSIR) in India and the Helmholtz Foundation in Germany.
• The purpose of the experiment was to see if the iron would cause an algal bloom and trap carbon dioxide from the atmosphere.

How well did it fetch?

• As expected iron fertilization led to the development of bloom during LOHAFEX, but the chlorophyll increase within the fertilized patch, an indicator of biomass, was smaller than in previous experiments.
• The algal bloom also stimulated the growth of zooplankton that feed on them. The zooplanktons in turn are consumed by higher organisms.
• Thus, ocean fertilization with iron also contributes to the carbon-fixing marine biomass of fish species which have been removed from the ocean by over-fishing.

Debate over its advocacy

• Mainstream activists are advocating solar geoengineering as a means to buy “humanity more time to cut greenhouse gas emissions”.
• Opponents of have numerous foundationally solid arguments. They warn against “taking our ecosystems even further away from self-regulation”.
• They argue that such actions distract attention from the need for deep cuts to gross emissions which is achievable with the right political will and resource mobilization.

Undesired consequences of geoengineering

• Conducting tests for geoengineering is a fallacy since these methods need to be deployed at a scale large enough to impact the global climate system to be certain of their efficacy.
• It is a large risk to take without knowing the potentially harmful consequences of such a planetary scale deployment.
• Some of these consequences are already known. Solar geoengineering, for example, alters rainfall patterns that can disrupt agriculture and water supplies.
• Injecting sulfate aerosols in the stratosphere above the Arctic to mimic volcano clouds, for example, can disrupt the monsoons in Asia and increase droughts.

Geopolitical concerns

• Manipulating the climate could have the same geopolitical function as nuclear weapons.
• Even before geoengineering is deployed, it may be used as a threat that will likely incite counter measures.
• Say if governments ever gain control of changing the course of potentially damaging storms, diversions that direct storms toward other countries may be seen as acts of war.

Suggestion

• Geoengineering cannot be treated as a magical mechanism to escape heightening concentrations of greenhouse gases (GHGs), while accepting the viewpoint that rapid decarbonisation is impossible.
• It also cannot be treated as a license to continue emitting more GHGs with no changes to current consumption and production patterns.
• Specific technologies that can help us achieve negative emissions need to be publicly funded and democratically administered to ensure that they serve the public interest.
• And they can only act as a supplement to scaling back of GHG emissions in all sectors, not a substitute.

Road Ahead

• We all know that climate change is growing more rapidly than anticipated earlier.
• Hence we should combine it with a programme of deep decarbonisation. This would help implement a “clean-up process” that will hasten our return to a more habitable environment.
• Scientists agree that natural climate solutions such as forest sinks cannot be relied upon for the scale of mitigation needed.
• Therefore, for a socially just application of such technologies for carbon capture with geological sequestration offers ‘negative emissions’.