Geo-engineering, also known as "climate engineering," is the deliberate large-scale intervention in the Earth's climate system to combat climate change. It includes techniques for removing CO2 from the atmosphere as well as technologies for rapidly cooling the Earth by reflecting solar energy back into space. In this article, we will discuss Geo-Engineering which will be helpful for UPSC exam preparation.

Purpose of Geo-Engineering

• The majority of geoengineering projects exist to mitigate the negative effects of industrial civilization on the Earth's climate.
• Because of deforestation and the use of fossil fuels, the Earth's atmosphere and stratosphere are absorbing increased levels of greenhouse gas emissions such as carbon dioxide (CO2) and methane (CH4).
• Humans can address atmospheric carbonization by conserving resources and reducing carbon emissions, but geoengineering schemes go a step further by actively removing greenhouse gases from the atmosphere and stratosphere.

Types of Geo-Engineering

Solar Engineering

• This type of geoengineering, also known as albedo modification or solar radiation management (SRM), aims to redirect incoming solar radiation back into space. This, in theory, will lower global temperatures.
• Solar geoengineering research has focused on marine cloud brightening (where clouds are sprayed with seawater), stratospheric aerosol injections (where added sulfate molecules in the stratosphere reflect incoming light), and launching massive mirrors into orbit to reflect sunlight.
• Simpler, more feasible methods include painting roofs and streets light colors to reflect sunlight rather than absorb it.

Carbon Capture

• Carbon geoengineering aims to reduce the number of carbon-based greenhouse gases in the atmosphere and stratosphere.
• It goes beyond simple emission reduction to include negative emissions. Some carbon capture methods, such as reforestation, afforestation (introducing trees to areas where they did not previously grow), and forest restoration, are relatively simple.
• Other carbon geoengineering techniques include extracting carbon dioxide from the atmosphere and storing it in pressurized underground caverns.
• Other carbon research programs have looked into the possibility of iron fertilization, which involves dispersing iron across the ocean to stimulate the growth of carbon-absorbing phytoplankton.

Bio-energy with Carbon Capture and Storage (BECCS)

• It is the process of extracting bioenergy from biomass and capturing and storing carbon from the atmosphere.
• The carbon in biomass comes from the greenhouse gas carbon dioxide (CO2), which the biomass absorbs from the atmosphere as it grows.
• As biomass is used, energy is extracted in useful forms (electricity, heat, biofuels, etc.) through combustion, fermentation, pyrolysis, or other conversion methods.

Ocean Fertilisation/ Ocean Nourishment

• Ocean fertilization is a type of climate engineering that involves the deliberate introduction of nutrients into the upper ocean in order to increase marine food production and remove CO2 from the atmosphere.
• A variety of techniques, including iron, urea, and phosphorus fertilization, have been proposed.

Soil Carbon Sequestration (SCS)

• Soils can act as a carbon dioxide sink now that atmospheric CO2 concentrations have surpassed 410 parts per million and oceans are becoming acidic.
• Carbon sequestration in soils has the potential to offset up to 15% of annual GHG emissions from fossil fuels.
• Plants, animals, microbes, leaves, and wood contribute to soil organic carbon (SOC), which is mostly found in the first metre or so.
• Temperature, rainfall, vegetation, soil management, and land-use change are just a few of the factors that influence SOC content.

Stratospheric Aerosol Injection (SAI)

• The most common type of solar radiation management (SRM) is SAI.
• In the case of SAI, gases are pumped into the stratosphere to reflect some of the sun's heat, simulating a natural effect in a strong volcanic eruption.
• The scale of SAI complicates governance because implementing it in one country can cause rain and extreme weather to spread across borders. The greatest challenge may be a lack of public support.

Marine Cloud Brightening (MCB)

• MCB involves some sort of reflection of sunlight away from the earth. In this case, sea salt or other particles are sprayed into the marine clouds to thicken and reflect them.

Cirrus Cloud Thinning (CCT)

• CCT is nearly the inverse of marine cloud brightening.
• Cirrus clouds at high altitudes are thin and whispy, so they do not reflect much solar radiation back into space and trap long-wave radiation on Earth.
• CCT proposes further thinning them through cloud seeding, allowing more long-wave radiation to escape.

How Geo-Engineering work?

Copy a Volcano

• A volcanic eruption can spew millions of tonnes of sulfur-dioxide gas into the atmosphere, forming a cloud that blocks some of the sun's radiation.
• Some scientists believe that by injecting sulfur into the atmosphere, they can also block solar radiation and potentially cool the planet.
• Those droplets are particularly effective at scattering the sun's light back into space. And, because sulfur does not heat the stratosphere as much as other aerosols, it would not work against the cooling effect.
• Hydrogen sulfide is a better candidate for atmospheric seeding than sulfur dioxide.

Shoot Mirrors into Space

• Geoengineers intends to launch a mirror the size of Greenland and strategically position it between the planet and the sun in order to deflect enough sunlight to restore the Earth's climate to pre-industrial levels.

Seed the sea with iron

• Iron, according to scientists, maybe the key to turning things around. Iron is preferred by phytoplankton, which live near the surface.
• They are also capable of removing carbon from the atmosphere during photosynthesis.
• When the organisms die after about 60 days, the carbon they have consumed sinks to the bottom of the ocean.
• Scientists believe that by pumping iron into the sea and stimulating phytoplankton to grow like crazy, global warming could be reversed.

Whiten the Clouds with Wind-Powered Ships

• Scientists hope that, like volcanic eruptions, cloud tops will reflect solar radiation.
• Spraying a large amount of seawater into the sky by wind-powered remotely activated ships in order to whiten the clouds and thus reflect solar radiation.

Build Fake Trees

• "Artificial tree," a scaled-down version of an earlier prototype capable of absorbing a tonne of CO2 from the atmosphere every day.
• Panels covering the tree's surface—approximately 50 square meters in size—will be made of an absorbent resin that reacts with carbon dioxide in the air to form a solid.
• It is similar to a furnace filter in that it can remove particles from the air.
• The panels, or "boxes," can be removed and exposed to 113 F steam, which cleans the filter effectively.
• The solid releases the carbon it has captured as a result of the chemical reaction with the steam, which can then seize as liquid CO2.
• However, removing carbon dioxide from the atmosphere is only half the battle; it must then be sequestered, or permanently trapped.

Drawbacks of Geo-engineering

• Scientists are unsure whether they will be able to halt some of these geoengineering projects once they begin.
• Geoengineering addresses the symptoms of global warming but may undermine efforts to address the root cause.
• People may believe that they do not need to reduce their personal carbon emissions, and businesses may continue to operate as usual, expecting researchers to clean up the mess.
• The cost and maintenance of geoengineering projects are extremely expensive.

Conclusion

Geoengineering is a theoretical method of mitigating the negative effects of climate change by removing CO2 from the atmosphere or limiting the amount of sunlight reaching the planet's surface. Geoengineering or climate engineering techniques include solar radiation management and ocean iron fertilization. Geoengineering addresses the symptoms of global warming while potentially undermining efforts to address the root cause.

FAQs

Question. What is geo-engineering?

Question. What are the types of geo-engineering techniques?

Question. What are the potential benefits of geo-engineering?

Question. What are the risks and challenges of geo-engineering?

Question. Why is geo-engineering controversial?

MCQs

1. What is the primary objective of geo-engineering?

A) To increase fossil fuel consumption

B) To reverse the effects of climate change

C) To promote industrial growth

D) To increase agricultural production

2. Which of the following is an example of Solar Radiation Management (SRM)?

A) Ocean fertilization

B) Carbon capture and storage

C) Stratospheric aerosol injection

D) Afforestation

3. What is the technique of ocean fertilization intended to achieve?

A) To increase ocean acidity

B) To reduce atmospheric CO2 by stimulating plankton growth

C) To increase the salinity of oceans

D) To increase the temperature of oceans

4. Which geo-engineering method involves the planting of trees to absorb CO2?

A) Carbon capture and storage

B) Afforestation and reforestation

C) Stratospheric aerosol injection

D) Bioenergy with carbon capture and storage

5. What is a major concern about geo-engineering techniques like solar radiation management?

A) They will decrease ocean temperature

B) They may have unintended impacts on weather patterns and ecosystems

C) They will not reduce atmospheric CO2 levels

D) They will increase industrial emissions

GS Mains Questions and Model Answers

Q1: Discuss the potential benefits and risks of geo-engineering as a solution to climate change.

Answer: Geo-engineering offers potential benefits in combating climate change, particularly when traditional mitigation efforts may take too long to produce results. Some potential benefits include:

• Carbon Dioxide Removal (CDR): Techniques like carbon capture and afforestation can reduce the level of CO2 in the atmosphere, helping to mitigate global warming.
• Solar Radiation Management (SRM): Methods like stratospheric aerosol injection may provide temporary cooling effects, reducing the immediate impacts of climate change.
• Global Cooperation: Geo-engineering could offer a global solution to climate change, benefiting all nations.

However, there are significant risks and challenges associated with geo-engineering:

• Environmental Uncertainty: Techniques like ocean fertilization could disrupt marine ecosystems, and stratospheric aerosol injection might alter global weather patterns, leading to unintended negative effects.
• Ethical Concerns: The use of geo-engineering raises questions about governance, who controls the technologies, and whether it is appropriate to modify the Earth’s systems.
• Dependence on Technology: Relying on geo-engineering may reduce the urgency of addressing the root causes of climate change, such as greenhouse gas emissions.

Thus, geo-engineering presents both opportunities and challenges and should be considered carefully in the context of broader climate strategies.

Q2: Evaluate the feasibility of solar radiation management techniques in combating climate change.

Answer: Solar radiation management (SRM) techniques aim to reduce the Earth’s temperature by reflecting a small percentage of sunlight back into space. Some techniques include stratospheric aerosol injection and marine cloud brightening. The potential benefits of SRM include:

• Rapid Cooling: SRM could provide a quick response to global warming by reducing incoming solar radiation and thus cooling the planet.
• Temporary Solution: SRM could serve as a temporary measure while other longer-term climate change solutions, like carbon emission reductions, are implemented.

However, the feasibility and risks of SRM are significant:

• Unpredictable Side Effects: SRM could alter global weather patterns, leading to regional droughts, changes in rainfall patterns, or disruptions to monsoon cycles.
• Ethical and Governance Issues: The use of SRM raises questions about who controls these technologies, and how decisions would be made about their deployment.
• Environmental Impact: There is concern that SRM would not address the root causes of climate change, such as greenhouse gas emissions, and could lead to geo-political conflicts.

While SRM could potentially mitigate temperature rise, its use requires careful research and global cooperation to minimize unintended consequences.

Q3: Assess the potential role of geo-engineering in India’s strategy for combating climate change.

Answer: India, like many other countries, faces the threat of climate change and may consider geo-engineering as part of its long-term strategy. Some geo-engineering techniques that could be considered include:

• Afforestation: India could use afforestation and reforestation to absorb CO2, especially in regions with vast deforested areas, contributing to carbon dioxide removal.
• Solar Radiation Management: While SRM could help mitigate some of the impacts of climate change, its use in India could pose challenges due to unpredictable effects on the monsoon and agricultural productivity.
• Carbon Capture: India could invest in carbon capture technology to reduce emissions from heavy industries, particularly in regions with high levels of industrial pollution.

However, geo-engineering poses several challenges for India:

• Environmental and Social Risks: Unintended side effects of geo-engineering could disproportionately affect vulnerable populations in India, particularly those dependent on agriculture and natural resources.
• Technological Feasibility: India may face challenges in implementing geo-engineering technologies, which could require significant resources and expertise.
• Ethical and Regulatory Concerns: The ethical implications of geo-engineering, including governance and global equity issues, will need to be addressed in India's climate strategy.

In conclusion, while geo-engineering could potentially play a role in mitigating climate change, it must be approached cautiously, and should be part of a broader strategy that includes emission reductions and sustainability efforts.

Previous Year Questions on Geo-engineering

1. UPSC CSE 2020

Question: "Explain the concept of geo-engineering and its potential as a solution to climate change."

Answer: Geo-engineering refers to deliberate large-scale interventions in the Earth's natural systems to mitigate the impacts of climate change. It includes techniques like carbon dioxide removal and solar radiation management. While geo-engineering offers potential solutions to rapidly address global warming, it carries significant risks and ethical concerns, particularly regarding unintended environmental consequences and governance.

2. UPSC CSE 2019

Question: "What are the advantages and risks of using solar radiation management as a geo-engineering technique?"

Answer: Solar radiation management (SRM) involves reflecting some sunlight back into space to cool the Earth. Advantages include quick cooling effects and temporary relief from global warming. However, SRM has significant risks, such as unintended changes in global weather patterns, regional droughts, and altered rainfall patterns. There are also concerns regarding governance and the potential for global conflicts over its deployment.