Outline

Carbon Sequestration

Carbon Sink

Carbon Credit

Carbon offsetting

Carbon Tax

Geo Engineering

Carbon Sequestration

Sequestration means capture and storage
Carbon sequestration is the process of capture and long-term storage of atmospheric carbon dioxide
It has been proposed as a way to slow the atmospheric and marine accumulation of greenhouse gases
Three steps

Carbon trapping/Separating Co2 from other gases

captured from the atmosphere th rough biological, chemical, or physical processes.

Transportation
Storing/Sinking

Natural Sinks - Oceans, forests, soil
Artificial sinks - Depleted oil reserves, unmineable mines

Types of Sequestration

Ocean Sequestration

Carbon captured will be stored in oceans through direct injection/fertilization (Negative effect of acidification)

Geological Sequestration

Natural pore spaces in geological formations serves as reservoirs for long term Co2 storage
Thought to be Largest potential
Mechanisms

Hydrodynamic Trapping

Co2 can be trapped as a gas under the low-permeability rock
Similar to natural gas in gas reservoirs

Solubility Trapping

Co2 can be dissolved into liquid or oil

Mineral Carbonation

Make Co2 to react with minerals, fluids, organic matter in a geological formation to form stable compounds/minerals largely calcium, iron, magnesium carbonates

CARBFIX project

It is a project in Iceland that tries to lock Co2 (as solid) inside the basaltic rocks [Note: not igneous]
How

Carbonated water is injected into the rocks
It reacts with Calcium, Magnesium or Silicate material present in Basaltic rocks.
CO2 is captured permanently without releasing any harmful by-products

Results

project was able to solidify 95% of the injected 250 tonnes of CO2 into calcite in 2 years, using 25 tonnes of water per tonne of CO2.

Cons

Expensive
Since the reactions are exothermic, it is reversible if the rocks are heated.
The pumping activity generates seismic activity

Hydrodynamic Trapping and solubility trapping combination is most effective

Terrestrial Sequestration

Large amount of carbon is stored in soils and vegetation which are our natural carbon sinks
Increased carbon fixation through photosynthesis, slowing down or reducing decomposition of organic matter, changing land use practices can enhance carbon uptake in these natural carbon sinks
Mangroves, wetlands, vegetation in higher latitudes (alpine, tundra) holds more carbon

Growing Seaweed that can be used to produce bio-methane.�
Bio-char produced by pyrolysis of bio waste.

It can be used as landfill and increase soil fertility.
Partly burnt biomass added to the soil absorbing additional co2

Carbon Sink

Black and Brown carbon are Green House Gases/Carbon Sources while Blue/Green carbon are carbon sinks

Green Carbon

It is carbon removed by photosynthesis of plants from atmosphere and stored in soils of natural ecosystems
Forests can accumulate large amounts of Co2 in relatively shorter periods and can hold for several decades
Afforestation and reforestation
High latitude forests store more carbon than tropical rainforests.
One third of the world’s soil-bound carbon s in taiga and tundra areas.
Temperate Forests beat Tropical For Capturing & Storing Carbon by area
Boreal Forests Store Twice as Much Carbon as Tropical by area [Reason - permafrost]
Mangroves & Coastal Wetlands Store 50 Times More Carbon than Tropical Forests by Area.

Bio diversity Variations

Latitude variation -Biodiversity is highest in tropics and decreases as we move towards poles
Altitude variation - Biodiversity decreases as we climb upwards a mountain
Biodiversity decreases as we move from coastal region to mid-oceanic ridges

Marine life decreases as we move away from continental shelf
However, highest concentration of Marine Phytoplankton (standing state) is found at Higher latitudes while tropics and subtropics have 10 to 100 times lower concentrations

High along Equator and coastlines where there are upwelling zones

Biodiversity is more in continents than oceans

80 percent in land, 15 percent in oceans, 5 percent in fresh water

Blue Carbon

Refers to coastal, marine, aquatic carbon sinks held by indicative vegetation(like phytoplankton), sediments, marine organism
Tidal marshes, mangroves, sea grass remove carbon from atmosphere and ocean, stores it in plants or depositing it in sediments
Each square km of coastal system can remove more carbon dioxide than the mature tropical forests

Blue Carbon Initiative

International initiative by Conservation International , IUCN, Intergovernmental Oceanic Commission of UNESCO
Incentives like carbon payment schemes for Blue Carbon Projects
Develop management approaches, financial incentives, policy mechanisms for ensuring conservation and restoration of coastal blue carbon ecosystems

Approaches to increase Soil Organic Carbon include

reducing soil erosion,
no till farming, (Zero till farmin g)
use of cover crops,
nutrient management,
applying manure and sludge,
water harvesting and conservation,
and agroforestry practices.

Carbon Credit

CC is a tradeable certificate/permit representing the right to emit one tonne of carbon or Co2 equivalent
It is one of the flexible market mechanisms provided in the Kyoto protocol to meet the emission targets
An organisation/industry with some new technology/investment which produces one tonne less Co2 than the standard level of emission earn one Carbon Credit
Use

It helps in investing in new technologies that emits lesser amounts of GHG
It also make developed countries to invest in developing countries and since developing countries have no emission targets, they achieve carbon credits which can be traded to developed countries.

However only portion of Carbon credits can be transferred to developed countries
India and China are largely biggest seller of Carbon credits with China capturing 70% world market share of CC
Indian share crossed $1 billion dollars
Carbon like any other commodity began to trade in India's Multi-Commodity Exchange MCX which became first exchange in Asia to trade carbon credits

Carbon Offsetting

Carbon offsetting - projects that offsets carbon/GHG emissions by creating renewable energy and thereby reduces/offsets the need of fossil fuel powered energy
Buying one tonne of carbon offset means that there will be one tonne less amount of Co2 in the atmosphere than there wou ld otherwise have been
Carbon offset -fastest way to achieve reductions
Emission reduction in one area should not cause increase in emission somewhere else
Carbon offsets are quantified and sold in metric tonnes of Co2 equivalent
Carbon offsets - renewable energy reducing the emissions equivalent
Carbon Credit - reduction in emission than standard
Carbon offset schemes cover all greenhouse gases but are measured in terms of carbon dioxide equivalent and can be awarded carbon credits.
Can be purchased by individuals or companies or countries

Carbon Tax

To disincentive in using fuels that contain carbon
India stand on carbon tax is "If rich countries impose carbon tax on Indian imports, they will be challenged in WTO"

Carbon price

A carbon price is a cost applied to carbon pollution to encourage polluters to reduce the amount of greenhouse gas they emit into the atmosphere

Geo Engineering

Aims at modifying and cooling Earths environment defeating the global warming and making life more habitable
Still it is theoritcal concept
5 big plans to stop global warming

Copy a volcano

Also known as Stratospheric aerosol injection
By injecting Sulphur into atmosphere just like volcano does, scientist believe that it could block solar radiation and potentially cool the planet. Since it is not a GHG, it will not absorb the radiation
Sulphur droplets scatter the sunlight back into space
Hydrogen sulphide is better for atmosphere seeding than Sulphur dioxide

Mirrors in space

Mirrors of size Green land will be placed in the strategic location b/w Earth and Sun
This will deflect sun's energy and keep the planet cool

Seeding the sea with Iron/Urea

By pumping iron into the sea, phytoplankton will grow in large amounts which capture Co2 from atmosphere
And when they die after about 60 days, the carbon goes to the sea bed along with the dead

Whiten the clouds with wind powered ships

Also Marine Cloud brightening
Clouds also reflect the incoming solar radiation
Spraying lot of sea water into sky by wind powered remotely activated ships to whiten clouds

Cirrus cloud thinning

Cirrus clouds are thinned or removed so that their long wave (IR wave) trapping capacity is reduced and hence cools the surface

Build Fake trees

Artificial trees made of absorbent resin that react with Co2 in the air and forms solid
The panes/boxes of artificial trees will be washed with 113F steam which cleans filter and releases that carbon which can be seized as liquid Co2
Also, the liquid Co2 again has to be sequestrated

Can be used for dry ice production
Horticulture needs Co2 for greenhouse effect
New type of plastic and concrete require Co2

Enhanced weathering

Dissolution of natural or artificially created minerals to remove carbon dioxide from the atmosphere.
Weathering is the natural process in which rocks are broken down and dissolved on the land surface.
When silicate or carbonate minerals dissolve in rainwater, carbon dioxide is drawn into the solution from the atmosphere
Mineral Carbonation
NOTE: Weathering results in carbon sequestration

Using pale-coloured roofing material
Growing high albedo crop

Drawbacks

Very expensive
No idea whether they can shut down when required once they start

Negative Emissions

Negative emissions are ways to remove carbon dioxide from the atmosphere, or even change the earth� radiation balance through geoengineering.
Emission Gap Report by UNEP listed out different strategies for negative emissions

Natural

Afforestation/Reforestation
Biochar

Partly burnt biomass is added to soil absorbing additional co2

Soil Carbon Sequestration

Land management changes that increases the soil carbon content resulting in net removal of co2 from atmosphere

Natural and Technological

Bioenergy with Carbon Capture and Storage

Plant turns co2 into biomass which is stored underground

Technological

Accelerated weathering

Mineral carbonation
Natural minerals react with co2 and bind them in new minerals

Direct Air capture
Ocean alkalinity enhancement

Alkaline materials added to the oceans to enhance atmospheric drawdown and negative acidification
Ex: Seeding the sea with iron/urea

Co2 to durable carbon

Co2 is removed from atmosphere and bound in long lived materials

Green Mobility

It refers to all those mobility options which emit lower CO2 g/km than pure internal combustion engine vehicles.
As of now, commercial viable options are

Bio-Fuel and Methanol Based mobility
CNG based mobility
Electric and Hybrid Mobility
Hydrogen Energy and Fuel-cell based mobility

Such technologies have potential to revolutionize the transportation of people and goods.

*As on 06 May 2021

Climate Engineering OR Mitigation Strategies