Chapter 2 - Climate Science & Risks, Impacts & Opportunities Flashcards
The Science of Climate Change
The greenhouse effect -> GHG air molecules allow solar radiation to pass through the atmosphere to warm the Earth’s surface, while at the same time stopping the heat radiation emitted by the Earth from escaping back into space, warms the planet.
Greenhouse gases, emissions and atmospheric concentrations - anthropogenic warming
Main GHGs are:
- Water vapour (H2O) (1 - 4 % conc)
- Carbon dioxide (CO2) (drives anthropogenic warming - fossil fuel combustion and industrial processes two thirds of all ghg emissions)
- Methane (CH4)
- Nitrous Oxide (N2O)
N2 and O2 make up more than 95% of the air not part of greenhouse effect
Intergovernmental Panel on Climate Change (IPCC) - IPCC Sixth Assessment (AR6), 1850-1900 to 2020 warming is at 1.1C, unequivocal human influence. 2023 hottest year on record, 1.48C above pre-ind levels (June to Dec faster rate of warming). faster warming since 1970.changes irreversible for centuries to millennia, esp in ocean, ice sheets, global sea level.
Prior to Ind Rev, natural atmospehric conc of CO2 remained around 280ppm for millennia. 417ppm in 2022
- some GHGs more effective than others at trapping the Earth’s heat radiation
- GHGs have different lifetimes
Metric of Global Warming Potential (GWP) -> warming impact of one molecule of a gas over a time horizon (20 or 100 years) compared to one molecule of CO2.
Can also express as carbon dioxide equivalent (CO2e) units - the concentration of CO2 required to cause the same warming effect (multiplying the concentration of a gas by its GWP)
7 GHGs
1. Carbon dioxide (CO2) - fossil fuel combustion, deforestation and industrial processes like producing cement. lifetime in atmospehre varies
2. Methane (CH4) has GWP of 28, fossil fuel combustion, agri and landfills. Lifetime of just udner 12 yrs in atmosphere. Essential to control methane emissions to mitigate human impact on climate. But long term impacts not as extensive as those of CO2
3. Nitrous oxide (N2O) has GWP of 273 -> fertiliser application, fossil fuel and biomass combustion, some industrial processes. Lifetime of 109 years
4. Hydrofluorocarbons (HFCs)types of refrigerants. All very high GWP eg. HFC-23 has a GWP of 14600 and lifetime of 228 years
5. Perfluorocarbons (PFCs) used in refrigerants and solvents, very high GWPs. eg. PFC-14 has a GWP of 7380 and lifetime of 50000 years.
6. Sulfur hexafluoride (SF6) has GWP of 25200 and comes from a limited amount of uses, in some electric insulation and manufacture of electric equipment. Lifetime 2300 years
7. Nitrogen trifluoride (NF3): GWP of 17400 , in electronics eg. semiconductor manufacturing. Makes up less than 0.0001% of emissions in the atmosphere, lifetime of 569 years.
Carbon sinks eg. land (Geological reservior), ocean, biosphere
co2 molecule chemically unreactive in atmosphere - natural removal of CO2 from the atmosphere can only occur via uptake by other carbon reservoirs.
- Removal flows of excess CO2 from the atmospehre via these carbon reservoirs = carbon sinks
Flows between these reservoirs = carbon cycle. - Uptake of carbon by the geological reservoir eg. through the formation of fossil fuel deposits, occurs only very slowly over 10s of 1000s of years and longer.
without human perturbance, the carbon cycle would be in equilibrium.
-> anthropogenically emitted CO2 is locked in and will change the climate for millennia
Carbon budgets, global impacts, inc planetary boundaries
global warming is roughly proportional to the amount of cumulative anthropogenic CO2 emissions. so if humans stop emitting CO2, global warming will not disappear but stop increasing further.
Carbon budget = amount of cumulative CO2 emissions
Carbon removal
- NATURE-based solutions (Nbs) - planting trees, mangroves and grasslands that soak up CO2 from the atmosphere
- Technological solutions - inc technologies like direct air carbon capture and storage (DACCS), which is the process of trapping CO2 from the air and depositing it in geological stores in a concentrated form
- Hybrid strategies inc examples like growing crops with enhanced roots, bioenergy with carbon capture and storage (BECCS) and ocean-based carbon removal solutions such as deep sea storage
Planetary boundaries
THE IMPACTS OF CLIMATE CHANGE
Global warming
Different potential climate futures
Climate sensitivity
Climate feedback processes
Feedback loops
Melting ice caps and sea level rises
Extreme weather and natural hazards
Accounting for climate change impacts
Challenges in climate modelling
Attributing impacts to climate change
Feedback processes and tipping points
Human choices
Assessing Macroeconomic impact and financial system risk
Financial system risk
Universal ownership
FINANCIAL IMPACTS OF CLIMATE CHANGE RISKS
Physical risks
Transition risks
- policy and legal
- legal (liability risks)
- technology risks
- Market risks
- reputational risks
SUPPLY, OPERATIONAL AND RESOURCE MANAGEMENT ISSUES RELATED TO CLIMATE CHANGE
Natural capital and resource scarcity
- Water scarcity
- Land use and degradation
- - reducing deforestation
- The ocean economy
Biodiversity and natural habitat loss
Supply chain vulnerability
Stakeholder relationships
the FINANCIAL MANIFESTATION of climate change
- Revenue
- expenditure
- assets
- liabilities
- financing
Stranded assets
Climate-related financial risks at the corporate level (private and public sectors)
- risk transfer tools for companies and investors
- Calculating Climate Value at Risk (CVar)
Climate-related financial risks at the public level and the opportunities for governments
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Investment materiality: asset, project and business activity assessment
SFDR
Climate-related opportunities
- Energy sources
- Resource efficiency
- using less materials by design
- material substitution
- fabrication yield improvements
eg. decarbonising steel
Circular economy
principles:
1. design out waste and pollution
2. keep products and materials in use
3. use renewable energy
4. regenerate natural systems
-currently remains a major CIRCULARITY GAP
Products, services, markets and diversification
Low-carbon goods and services exist in all sectors across the world. A future low-carbon economy will create a transformation in the range of products and services offered by businesses, as well as the business models to serve them/
The low-carbon transition will also require significant structural changes to the economy that will create new national markets.
Sharing economy business models
Adaptation and resilience
Global Commission on Adaptation (GCA) five target areas:
Assessment of social factors related to climate change
Health and labour productivity
case study - heat stress and labour productivity
Food security
- negative impacts of climate change are expected to outweigh any positive benefits
Security and migration
new displacements by disasters (broken down by hazards)
Cities and urbanisation
Disaster preparedness and resilience
Achieving a ‘just transition’
