CLIMATE CHANGE MITIGATION APPROACHES Flashcards
There are 3 main climate change mitigation approaches, these are:
- Conventional mitigation efforts
- Negative Emissions Technologies
- Radiative Forcing Geoengineering Technologies
- employ decarbonization technologies and techniques that reduce CO2 emissions, such as renewable energy, fuel switching, efficiency gains, nuclear power, and carbon capture storage and utilization.
Conventional mitigation efforts
Conventional mitigation efforts:
a. Carbon capture and storage
b. Fuel switching
a. Efficiency gains
- is a promising technology as a potential decarbonization approach to be applied to the power as well as the industrial sectors.
Carbon capture and storage
The Carbon capture and storage technology consists of _______ and ________ CO2 gases from processes that rely on fossil fuels such as coal, oil or gas. The captured CO2 is then transported and stored in geological reservoirs for very long periods.
separating; capturing
The main objective of carbon capture and storage is the reduction in _________ while utilizing fossil sources.
emission levels
- in the power sector from coal to gas, in the short-term, as a potential approach to economically transition to a low carbon and hopefully a zero-carbon economy in future. The move to natural gas is also applicable to industry, transportation and building sectors; however, as discussed previously the switch to renewable fuels is a more sustainable approach creating further decarbonization potential in these sectors.
Fuel switching
- in the power sector are achieved through improvements in thermal power plants by enhancing the efficiency of fuel combustion as well as improving turbine generator efficiencies. Furthermore, waste heat recovery for additional thermal as well as electric production enhances efficiency. In gas-fired power plants, the utilization of a combined cycle technology enhances the efficiency significantly.
Efficiency gains
_______ and ________ have also played an interesting role in efficiency gains. Technological advances within transmission and distribution networks also enhance efficiencies by reducing losses.
Combined heat; power units
- These are also referred to as carbon dioxide removal methods.
Negative Emissions Technologies
Negative Emissions Technologies techniques are potentially deployed to ______ and ______ CO2 from the atmosphere.
capture and sequester
Negative Emissions Technologies Techniques:
a. Bioenergy carbon capture and storage
b. Biochar
c. Enhanced Terrestrial weathering
d. Direct Air Carbon Capture and Storage
e. Ocean Fertilization
f. Ocean Alkalinity Enhancement
g. Soil Carbon Sequestration
h. Afforestation and Reforestation
i. Wetland construction and restoration
one of the prominent negative emissions technologies and as potential route to meet temperature goals. The basic principle behind the technology is biomass biologically captures atmospheric CO2 through photosynthesis during growth, which is then utilized for energy production through combustion.
Bioenergy carbon capture and storage
Bioenergy carbon capture and storage - The CO2 emissions realized upon combustion are then captured and stored in suitable _________. This technology can significantly reduce greenhouse gas concentration levels by removing CO2 from the atmosphere.
geological reservoirs
- is produced from biomass, e.g. dedicated crops, agricultural residues and forestry residues, through a thermochemical conversion process.
Biochar
Biochar is produced through _______, a process of heating in the absence of oxygen, as well as through gasification and hydrothermal carbonization.
pyrolysis
Biochar is a ________ substance that’s made by burning organic material from agricultural and forestry wastes (also called biomass) in a controlled process called pyrolysis. Although it looks a lot like common charcoal, biochar is produced using a specific process to reduce contamination and safely store carbon.
charcoal-like
In the natural system, silicate rocks decompose; this is a process termed _________.
weathering
- is an approach that can accelerate this weathering process to enhance CO2 uptake on a much shorter timescale. This is achieved through milling silicate rocks to increase its reactive surface and enhance its mineral dissolution rate. The ground material is then applied to croplands providing a multitude of co-benefits.
Enhanced weathering
- The underlying principle behind this technology is the use of chemical bonding to remove atmospheric CO2 directly from the air and then store it in geological reservoirs or utilize it for other purposes such as the production of chemicals or mineral carbonates.
Direct Air Carbon Capture and Storage
- is the process of adding nutrients, macro such as phosphorus and nitrates as well as micro such as iron, to the upper surface of the ocean to enhance CO2 uptake by promoting biological activity
Ocean Fertilization
Microscopic organisms, called ________, found at the surface layer of oceans are an important contributor to the concept of oceanic carbon sequestration.
phytoplankton
The sequestered CO2, in the form of organic marine biomass, is naturally transported to the deep ocean; this process is termed “_______________”.
the biological pump
- is an approach to carbon removal that involves adding alkaline substances to seawater to enhance the ocean’s natural carbon sink.
Ocean Alkalinity Enhancement
- is the process of capturing atmospheric CO2 through changing land management practices to increase soil carbon content. The level of carbon concentration within the soil is determined by the balance of inputs, e.g. residues, litter, roots and manure, and the carbon losses realized through respiration which is mainly influenced by soil disturbance. Practices that increase inputs and/or reduce losses drive soil carbon sequestration.
Soil Carbon Sequestration
Soil carbon sequestration promotes _____________ and health as well as improves crop yields due to organic carbon accumulation within soils (Fuss et al. 2018).
enhanced soil fertility
- During tree growth, CO2 is captured from the atmosphere and stored in living biomass, dead organic matter and soils. Forestation is thus a biogenic negative emissions technology that plays an important role within climate change abatement efforts.
Afforestation and Reforestation
Forestation can be deployed by either establishing new forests, referred to as ________
afforestation
re-establishing previous forest areas that have undergone deforestation or degradation, which is referred to as __________.
reforestation
Depending on tree species, once forests are established CO2 uptake may span _____ years until trees reach maturity and then sequestration rates slow down significantly. At that stage, forest products can be harvested and utilized.
20–100
Afforestation and reforestation have already been widely adopted on a global level and have already been integrated within climate policies through the ________ clean development mechanism program since the 1990s.
Kyoto protocol’s
Forest-based abatement projects have also been introduced through national regulations as well as voluntary systems such as the ___________ programme that was introduced by the United Nations in 2008.
reducing emissions from deforestation and forest degradation (REDD+)
Wetland construction and restoration - ________ are high carbon density ecosystems that facilitate atmospheric carbon sequestration through photosynthesis and subsequent storage in above-ground and below-ground biomass as well as soil organic matter.
Wetlands
Examples of wetlands include:
- peatlands
- coastal habitats such as mangrove forests, tidal marshes and seagrass meadows, also referred to as blue carbon ecosystems.
an ecosystem that accumulates plant material overtime and store an average of 10x more carbon per hectare than any other ecosystem
Peatland
While peatlands and coastal wetlands are estimated to store between ________ of the world’s terrestrial biological carbon, such carbon stocks are vulnerable to deterioration due to habitat degradation.
44 and 71%
Dou you know the colors of carbon? They are:
a. Blue Carbon
b. Black Carbon
c. Brown Carbon
d. Red Carbon
e. Green Carbon
f. Teal Carbon
- the carbon captured by the oceans and coastal ecosystem including seaweed and sediments
Blue Carbon
- the soot emitted during incomplete combustion of fossil fuels in coal-fired power plants, cars and other equipment.
Black Carbon
- originates primarily during the combustion of organic biomass and is a close cousin of black carbon
Brown Carbon
- it includes all living biological particles on snow and ice that reduce albedo to survive
Red Carbon
- reflects the carbon sequestered by land ecosystems
Green Carbon
- the carbon stored in inland freshwater wetlands
Teal Carbon
Radiative Forcing Geoengineering Technologies - The main objective is temperature _____ or ______.
stabilization or reduction
Unlike negative emissions technologies, this is achieved without ______ greenhouse gas concentrations in the atmosphere
altering
_______________ are a set of technologies that aim to alter the earth’s radiative energy budget to stabilize or reduce global temperatures. This is achieved by either increasing the earth’s reflectivity by increasing shortwave solar radiation that is reflected to space, termed solar radiation management, or by enhancing longwave radiation that is emitted by the earth’s surfaces to space, termed terrestrial radiation management.
Radiative forcing geoengineering techniques
Major radiative forcing geoengineering technologies that aim to alter the earth’s radiative energy budget to stabilize or reduce global temperatures. These technologies include:
a. stratospheric aerosol injection,
b. marine sky brightening,
c. cirrus cloud thinning,
d. space-based mirrors and
e. surface-based brightening
These substances could include minerals, such as _______, or artificial substances, such as _______
olivine; lime or some industrial byproducts
