Revision Flashcards
(122 cards)
1
Q
Discovery of greenhouse gas
A
John Tyndall in the 1800s. Made a machine which measured how much different gasses could absorb radiant heat.
2
Q
Contributions to GHG emissions
A
Fossil fuels and industry, then land use change and forestry, then non-co2
The growth rate is slowing
3
Q
How much radiative forcing do different gasses drive
A
Methane 25% (0.4c)
Nitrous oxide 5% (0.1C)
CO2 69% (1.1*C)
4
Q
Other greenhouse gasses
A
Sulphur hexafluoride (SF6)
PFC-14 (CF4)
HFC-152a(CH3CHF2)
5
Q
Global warming potential (GWP)
A
Ratio of time-integrated forcing from instantaneous release of 1KG of gas to that of 1KG CO2
How much energy the missions of 1ton of a gas will absorb over a given period relative to emissions of 1 ton of CO2
Allows comparisons of warming impacts of different gasses
6
Q
Methane atmospheric lifetime
A
12 years.
Very dynamic- reacts with other things
7
Q
GWP*
A
GWP100 treats short lived methane like long lived CO2. Indicates warming until methane reaches 0 rather than when emission rate is below sink.
GWP* links temperature impacts of short lived climate pollutants a pulse emission of CO2
One cow producing 100kg of co2 (Tons)
GWP20: 8.4 GWP100:2.8 GWP*:0.7
8
Q
Temperature extreme, precipitation risk and drought
A
Confident that almost everywhere will see increased temperature extremes: unsure where limited data or hard tk reach
Less certainty with precipitation: harder to model changes in patterns. Areas of projected increase have low confidence
Similar to precipitation.
9
Q
Global fire risk
A
Increases with drought.
Fire seasons have increased by 25%
10
Q
IPCC
A
Inter governmental panel on climate change- international authority.
Organised COP, releases assessments and methodologies (synthesised from research)
Organises commitments to climate change
11
Q
Paris agreement
A
COP21
International legally binding agreement to:
Limit global warming to below 2c, preferably 1.5c
5 years cycle of increasingly ambitious national climate action (ratchet mechanism)
By 2020 submit plans for climate action known as nationally determined contributions (NDC’s) e.g. uk will reduce economy wide GHG emissions by 68% by 2030 compared to 1990 or Guatemala reducing 1500ha of mangroves by 2025
12
Q
Adaptation definition
A
Adjustments in ecological, social or economic systems in response to actual or expected climatic stimuli and their effects
13
Q
UKs national adaptation programme
A
Risks associated with 2 scenarios: 2 and 4
Gear exhaustion, colder winters, water stress in agriculture, help internationally: food chains
14
Q
Mitigation definition
A
Human intervention to reduce sources or enhance sinks of greenhouse gases
15
Q
How can we limit global warming
A
Net zero anthropogenic CO2 emissions
16
Q
How much warming does 1000 giga tons of CO2 produce
A
Best IPCC estimate is 0.45*C
17
Q
Carbon budget
A
How much carbon we an release and not exceed X amount of warning
1.5*C is 500Gt
2*C is 1.150Gt
Total anthropogenic emissions were 40.7Gt in 2022
18
Q
Growth of global emissions
A
Slowly declining- reached +0.5% per year over 2013-2022
19
Q
Current carbon budget
A
We are currently at 1.1*c
Current targets and pledges will see around 2.6*c
Current policies will see around 2.9*C
20
Q
Who contributes to climate warming
A
Poorest 50%- 7%
Middle 40%- 41%
Richest 10%- 37%
Richest 1%- 15%
The top 11% contribute 52%
They need to be targeted the most
21
Q
Climate change equity
A
Issues of equality, justice and fair ESS arise with respect to mitigation and adaptation.
Many areas of climate change policy-making involve value judgements and ethical considerations
22
Q
Co-benefits of climate change mitigation
A
It intersects with other society goals creating the possibility of co-benefits or adverse side effects
23
Q
Planetary boundaries
A
A safe operating space for humanity- how to use natural resources without reducing future generations ability to do so too
We are exceeding:
Novel entities (pollutants)
Biogeochemical flows (P and N)
Freshwater change
Land system change
Biosphere integrity (functional and genetic)
Climate change
24
Q
Which sector contributes most to climate change
A
Electricity and heat production
25
What contributes most to climate change
Electricity and heat production
agriculture and other land use industry
Transport
Buildings
Other
26
Climate policy key events
1988 IPCC established. Testified to Us senate that climate change has started.
1990 IPCC produced first assessment report- human activities are increasing greenhouse gasses and need global treaty.
1992 UN framework for climate change set up. Starts COP. Rio earth summer was first.
1994 more people join COP now 196 countries
1995 Angela Merkel presides COp 1
1997 Kyoto protocol. First global treaty- countries must limit and reduce the emissions to individual targets. More responsibility on developed countries
2013- 5th IPCC assessment report. Human influence on climate is clear and emissions are highest in history. Climate changes impact human and natural systems
2015- the Paris agreement
2023- cop 21 (Dubai) global stock take released (progress assesment). Some progress made from 3.7-4.8 warning to 2.4-2.6. 1.7 if all pledges met.
27
Kyoto protocol mechanisms
1997 Kyoto protocol. First global treaty- countries must limit and reduce the emissions to individual targets. More responsibility on developed countries
Market mechanisms-
Emissions trading: allows countries to sell excess emissions to those over target
Clean development mechanism: allows countries with emission reduction to implement emission reduction projects in developing countries (sustainable development)
Joint implantation- allow countries to earn emission reduction units from emission reduction/removal projects in other countries.
28
Kyoto protocol monitoring
Registry systems to track and record transactions
Reporting done in annual emissions inventories
Compliance confirms parties meet commitments
29
Paris agreement
Signed in 2015
Signed by 196 parties.
Goal to limit warming to below 2*C, preferably below 1.5*C
5 year cycle of increasingly ambitious national action- (ratchet mechanism)
By 2020 submit plans for climate action as nationally determined contributions (NDC’s)
30
UK’s NDC
Reduce economy wide GHG emissions by 68% by 2030
31
Thomas Malthus
Populations will exponentially grow- food production will be exceeded by need
Malthusian catastrophe is the point when population outgrows food and mass famine
Our food production methods are improving and population is predicted to stabilise at 10 billion
32
Three pillars of sustainability
Social
Economic
Environment
33
Sustainable development definition
Development which meets the needs of the present without compromising the ability of future generations to meet their own needs
34
Five capitals approach to sustainable development
Putting monetary benefits to the environment
Manufactured- material goods
Financial- ownership and trade
Human- health and wellbeing
Social- institutions to support human capital
Natural- any stock/flow of energy and material which produces goods and ecosystem services (environment)- supports everything else
35
Ecosystem services
The direct and indirect contributions ecosystems (natural capital) provide for human wellbeing
Supporting- necessary for other services. Biomass and O2 production, water and nutrient cycling
provisioning- material benefits. Food, raw minerals, medicines
regulating- moderate natural phenomena. Air quality, carbon sequestration and storage, moderating extreme weather, wastewater treatment, soil fertility maintenance, pollination
cultural
36
Millennium ecosystem assessment
Assed human impacts on environment- published in 2005
Highlighted dependency on healthy environment from humans.
Degradation of ecosystem services is key barrier in achieving millennium development goals (8 targets aimed to be achieved by 2015)
37
UN sustainable development goals
Replaced 2015 goals. Current guide
No poverty, zero hunger, quality education, gender equality, affordable and clean energy, clean water and sanitation, decent work and economic growth, responsible consumption and production, life below water and on land, peace, justice and strong institutions
38
Eight scenario impact categories
C1- limit warming to 1.5 with no/little overshoot
C2- return to 1.5 after overshoot
C3- limit to 2
C4- limit to 2
C5- limit to 2.5
C6- limit to 3
C7- limit to 4
C8- exceed 4
C123 are likely
39
Illustrative mitigation pathways
Denote impacts of different choices on development of society.
Included two reference pathways:
Current policies implanted (CurPol)
Implement NDCs (Modact)
Different scenarios;
High reliance on renewables (very good!)
Energy demand reductions (very good!)
Carbon dioxide removal in energy and industry sectors to reach net emissions
Mitigation in sustainable development (Best!)
Less rapid and gradual strengthening of near-term mitigation actions
40
Global methane pledge
Cop26
Commitment for most contributing countries to reduce global methane emissions by at least 30% by 2030
41
Climate finance
Money being used at local, national or trans-national scales In private, public and alternative funding sources to support mitigation and adaptation
In 2021 it was $850 billion BUT fossil fuel subsidies were $5900 billion
42
Types of climate finance
Green bonds- debt issued by public or private institution to fund climate tackling
Debt Swaps- sale of foreign currency debt by creditor to and investor which can swap the debt with debtor for development of mitigation projects
Guarantees- commitments where guarantor promises to fulfill obligations undertaken by borrower to lender
Concessional loans- loans for mig/adaptation that differed from traditional loans in longer repayment periods and lower interest
Grants/donations- funding which needs no repayment
43
Sources of climate finance
Green climate fund- established by UNFCCC in 2010 to support developing countries
Special climate change fund- administered by Global Environemnt Facility
Provides four finance services including adaptation, tech transfer, energy/transport/industry/agriculture/forestry/waste water management, economic diversification for countries dependent on fossil fuels
UN-REDD+ programme
Est.2008. Programme to reduce forest loss and degradation. Pay countries for emission reductions
44
Carbon credits
Carbon credits represent quantities of greenhouse gas that have been kept out of air/removed.
Voulenteer carbon markets describe credits which are purchased voluntarily (rather than to comply)
Voluntary carbon credits provide direct private financing to climate action projects
They must represent additionally (represent things which would have not otherwise happened)
Ensure it is not overestimated and removal is permanent. No double reporting or association with societal or environmental harms
Projects were vastly overestimated (90% did not repesent real change)
45
Steps to good carbon credit
Pre-reality study
Project viability
Planning
Project development and implementation (validation and accreditation!!)
Ongoing project operation (third party verification and credit issued here)
46
Net zero definition
A state in which greenhouse gasses going into atmosphere are balanced by removal of gasses
Address scope 1, 2 and 3 emissions
47
Carbon neutral
Ignores other gasses
48
Decarbonisation
Mitigation, Cessstion or reduction of carbon in atmosphere
49
Uk climate change act 2008
First in the world!
Legally binding goals to reduce greenhouse gasses by at least 80% by 2050 compared to 1990.
Updated in 2019 with Paris agreement to 100% below
50
Mission zero
A review published in Jan 2023 reviewing evidence to conclude net-zero is a change for growth
129 reccomendstions for how to create green economy but main gist is;
Back buisness and local action, deliver energy efficient homes and increase transparency and enhancement with people
51
Features of net zero transition
Universal/comprehendive- all sectors will be transformed and most are highly dependent. Supply chains transformed.
Significant- economic transformation is substantial- needs to be $3.5 trillion by 2050
Front loaded- earlier means lower long term costs
Uneven- certain sectors will have to transform the most
Risk exposure- physical climate rinks are uncertain and disorderly transitions may present new challenges eg. Insufficient energy.
Opportunity- new technologies new opportunities for individuals and buisness
52
GHG vs Air quality pollutants
53
GHG vs AQ pollutants
GHG:CO2, CH4.
AQP:NOx. VOC, NH3, SO2
both:black carbon, semi/intermediate volatile organic compounds (SVOC/IVOC), O3
54
Secondary aerosol
NOx, SO2 NH3 and VOC are precursors
They scatter radiation back to space and contribute to radiative properties of clouds
Aerosols cool.
55
Black carbon
Air quality pollutant.
Product of incomplete combustion from diesel.
Can force positive radiation forcing my absorption.
When in ice contributes to melting.
When as smoke reflects if compared to ocean.
No mitigation reduces my 3%.
Reduce by 35% for 1.5 target
Reduction involves harnessing renewables, managing wildfire and zigzag kilns
56
O3
One of the largest components of radiative forcing
NOx, VOC and CO are precursors.
O3=Ozone
NO2 breaks down to form ozone- product of combustion.
Air quality concerns ground level, RF concerns higher.
Short lifetime!
57
BVOC
Biogenic VOC
Comes from trees
Oxideses to O3 and secondary organic aerosol
Tree planting schemes should account for this
Hot dry summers reduce ozone uptake- increasing ground level.
Winter smog less likely
58
Choosing models
Consider info available. Know objectives
Consider complexity
Consider price of running the model
3D looks at hydro, bio and atmosphere, meteorlogy and emissions- but expensive
1D models only look at vertical/plumes.
0D no transport but detailed chem. short lived species.
Simple chemistry has 20, complex may be 100. Nothing includes everything
59
Air pollution mitigation
Has been focused on legislation and tech changes. Not considered climate.
Can be categorised as energy conservation, efficiency, abatement (new tech), fuel switching, demand management, behavioural change.
60
Diesel vs petrol
Diesel better than petrol for GHG
But has lager engines, larger refinery demand and Black carbon emissions- reduced CO2 benefit.
Selective catalytic reduction- reduces CO2 and NOx emissions and improves engine efficiency
61
GHG inventories
A list of emission sources and the associated emissions quantified using standardised models
UNFCCC has reporting standards which countries report by in 5 areas: energy, industrial, agriculture, land use/change/forestry, waste.
62
Scope 1
Emissions are direct GHG emissions from sources controlled or owned by and organisation
63
Scope 2
Indirect emissions e.g. associated with purchase of electricity or heating/cooling
64
Scope 3
Emissions from assess not owned/controlled by reporting organisation but the organisation indirectly affects in supply chain. E.g. end of life treatment, transport, packaging.
65
Life cycle assessment
LCA is a systematic analysis of potential environmental impacts of a product during whole life.
66
LCA components
Primary outputs are stated as relevant functional units, usually how the product is consume/used.
System boundary. Full cradle to grave is ideal. Should cover all, but often only partial. Can’t account for disposal rtc
67
LCA limits
Only looks for incremental improvement not whole change.
Rely on industry averages and lack primary data- data on uk farm management may not be equivalent to US.
Do not include social implications or economic ones
Time consuming to produce and require expertise to think it all through.
68
Contributors to carbon footprint
Food (beef, chocolate and coffee worst)
Home electricity and heating- higher per person in developed countries.
Consumer goods- computers have high footprints
Travel- high emissions associated with flights, especially domestic.
69
Aviation emissions at
Accounts for 2.5% of CO2- overall impact is greater due to short term increase in ozone then decrease long term.
Increases emissions of water vapour, soot, sulphur and aerosols.
Overall warming more like 3.5%
Tech has gotten better- emissions increased by 7X since 80s BUT flights by 300
70
Geoengineering
Also called climate engineering.
Large scale interventions in earths natural systems. IPCC says CO2 removal/ solar radiation management
71
Solar radiation management
Reflecting solar radiation back.
Space mirrors- anything from satellites to clouds of dust. Would block 2-4% warming. Tech limitations, expensive and poorly understood.
Stratospheric aerosol injection- mimic natural effect of volcanic eruptions. Release of SO2.
Cloud thinning- high altitude clouds absorb radiation. Seeding clouds with solid aerosols can cause dissipation.
High albedo crops and building- make things whiter to reflect more. Can be by painting or Gm crop.
Ocean mirrors- deep ocean absorbs 93% of solar radiation. Microbubbles to increase seafoam- impact ecosystems.
Marine cloud brightening- spray seawater to act as condensation Nuclei. Water vapour make cloud larger and brighter.
72
Negative emission technology
Solutions to remove CO2 directly from atmosphere.
Direct air capture- removes CO2 using chem. processes. Not the same as carbon capture storage. CO2 captured can be used for meat packaging and drinks.
Lime soda- put sodium hydroxide in contact with atmosphere: transfer the sodium carbonate back by reaction with lime.
Ocean alkalinity enhancement: uses lime to trap in a mine form in ocean. Lowers ocean pH.
Iron fertilisation- put Fe particles into ocean. Interact with plankton
Biochem- apply high carbon stuff to soil.
Bioenergy with carbon vampire storage- combust biomass in plant with CCs. Hugh scale up potential.
73
Baseload
Background energy requirement. Half of total energy demand.
Covered in UK by baseload Powerplanrs. Don’t produce variable load.
Future should reduce base load plants and increase adaptability. A mix of renewables could do that.
74
Hydrogen
High cost energy atm but being researched. When burned only produces water. Easy to transport.!
Grey hydrogen- from natural gas
Green- electrolysis or biological processes. Needs to be produced with 100% renewable:
Expected to grow 10% annually.
75
Electric transport
Electric cars are 15% of car market.
76
Mitigation hierarchy
Avoid, minimise, rehab/restore, offset
Avoid is best but most costly, offset is least effective but cheap
77
Total carbon stocks
Ocean depth- 40000Gt
Fossil fuels- 10000Gt
Land surface- 3000Gt
Ocean surface- 800Gt
Atmosphere- >750Gt
Most flux is between land surface and atmosphere, then ocean surface and atmosphere
78
Carbon sink
Mechanisms or entities which remove CO2 from atmosphere
79
Carbon Stocks
Quantity of carbon stored in a pool at a specified time
80
Carbon Pools
A system that has the capacity to store or release carbon. E.g. above/below ground biomass, deadwood, litter, soil organic matter in forests
81
Carbon sequestration
Removal of carbon from atmosphere into a sink
82
Carbon colours
Green- stored in plants and soil
Blue- ocean and coastal stored
Grey- fossil fuels
Black- component of particulate matter (air pollution) from incomplete combustion
83
Forest degradation
The reduction/thinning of canopy caused by a reduction in tree density. Often temporary and expected to regrow but does have carbon storage impacts
84
Afforestation VS reforestation
Afforestation- establishment of a forest/stand of trees where there is no recent history
Reforestation- forestation of land which has contained forests
Both offset some deforestation
85
Forest types
Primary- native species with no visible indication of human activities or disturbed ecological process
Naturally regen- visible indicators of human activity: logged over areas, regenerating agric land, recovering from fire
Planted- trees established through deliberate activity
86
Limits to tree planting
Time is needed
Climate feedbacks can impact stability of carbon stored
Protection and responsible management needed
Not all locations are appropriate
Plants require monitoring
New woodlands tend to be planted with a a limited number of species (low biodiversity value)
87
Woodland carbon code
Quality assurance standard in the UK to verify carbon units for carbon credit schemes.
88
IUCN peatland code
Similar to woodland code. Certifications of carbon storage to finance efforts.
89
Great fen project
Largest peatland restoration project in Europe.
Aims to restore and create habitat, improve access and enjoyment, encourage socio-economic development, contribute to local climate change adaptation and mitigation
90
Soil carbon storage
Organic and organic carbon makes total
Not all organic matter = organic carbon- carbon is around 58%. Varies between system
SOM contains complex and simple compounds, microbial communities and stabilised carbon.
Carbon accumulates is immobilisation>mobilisation
91
Enhancing soil carbon sequestration
Main ideas:
Zero tillage - enhances stocks over time, mostly in surface. Chemistry changes to less likely to be released following disturbance.
Intercropping/agroforestry
Cover cropping
Rotation grazing
Organic management
92
Societal solutions
Reduce meat consumption- land use
Organic farming- increase sequestration and organic inputs. Lower yields and land which can be used though.
Circular economy- minimise resource use and take waste back into the economy. Natural principals are efficient with waste- mimic that. Eliminate waste + pollution, circulate products and materials in highest value state, regen nature. Design out waste; build resilience through diversity, think about whole systems.
93
Climate wedge
A strat to reduce emissions using existing tech whose impact grows form 0-1Gt a year in 2050.
94
Water budget
A tool to quantify the flow of water in and out of a system. Rate of change of water stored.
95
Water supply resilience
Is there enough water quantity and quality to support social economic activity.
Resilience; ability to withstand shocks and continue to function
96
Water Vapor in atmosphere
Accounts for 60% of earths warming effect
Haze- warms. Reduces radiation reaching ground
Clouds- cooling effect. reflective surface.
97
98
Wetland water table
Higher = more carbon stored.
Above water table organic carbon is more easily degraded.
Under water table anoxic conditions reduce microbial activity
99
Mitigating impact of climate change on freshwater
Water conservation- reducing loss and increasing efficiency to increase availability
Storage and management- damns and reservoirs can manage availability during drought/low rainfall
Quality- address pollution and improve wastewater treatment
Sustainable land use- maintain ecosystems to support freshwater
100
Features of nature based solutions
Broad in scope and definition
Nature meaning multifunctional, conserving and adding to the stock of natural capital or adaptable
Bottom up
Action orientated
101
Water targets
83% decline in biodiversity. Wetlands are disappearing 3X faster than forests.
Aim to by 2030 ensure fresh water systems support and sustain biodiversity and human needs.
102
Climate change targets
103
Future agric challenges
Population growth
Reduction in suitable land
Changing weather patterns
Increased chance of extreme weather events
Increasing demand for higher input diets
104
How much soy goes where?
20% direct to people
76% to animals
4% to industry
105
How much GHG does agric output
13% directly
35% whole systen
106
Landfill
Produces 14% of methane.
Ensuring waste is covered and sealed allows gas to be funneled and used rather than released.
107
Self sufficiency
Import/export may be cheaper but not as sustainable.
We are self sufficient in oats and barley but other things not so much.
108
Industrial agric changes
Monoculture
Resource intensive
Land clearing
Mechanisation
Plant breeding
Tech advancements
Crop production Increased by 40% and animal by 9 on 10% less land
109
Pros and cons of climate change for agriculture
Pros: more growing season, more CO2= less photo respiration
Cons; altered pests + diseases, increased extreme weather, more floods + droughts
110
How to reduce agric GHg
Crops: fertiliser management, more legumes and cover crops, rice management
Grazing/livestock- fire + nutrient management, deep rooting species, nutrition+ genetics
Agric peat-land- raise water levels, grow wetland crops for biofuel/construction
Integrated systems
111
Rice genes
SK1- chronic. Rice grows faster to reach above floodwater
Sub1A- accute. Plant goes dormant then grows.
112
Improving cows
Feeding silage from earlier growth stages improves digest ability, Milk yield and methane
Unsaturated fatty acids- inhibits availability of bacteria in Rumen, binds hydrogen
Genetics selection
113
Farming attitudes
Farmers important for designing and implementing policies. When asked to rate importance of GHG consideration:
17% very important, 47% fairly. 6.5 not at all.
114
Actions being taken by farmers
Recycling waste, improving energy efficiency, nitrogen fertiliser application accuracy, increasing use of clover, increasing legumes in crop rotation, nitrogen feed efficiency
80% consider it good buisness pracie and a little less do it out of concern for environment
115
Barriers to farm changes
Unsure of what to do, lack of incentive or info, don’t believe it’s needed, price, or already done what they can
116
Which sector contributes the most to climate change?
Electricity + heat production
117
Which gases contribute most to warming
Carbon dioxide
Methane
Nitrous oxide
118
Carbon pools
2500 gt soils
800gt atmosphere
560gt plant+ animal life
119
Green bonds vs concessional loans
Green bonds from public or private institution to fund climate mitigation and adaptation
Concessional loans are for climate change action with long repayment periods and low interest rates
120
Problem with soils as carbon sink
Loosing carbon due to management
121
Limitations to tree planting targets
Time needed
Feedbacks may impact stability
Protection + responsible management needed
Not all locations suitable
Plants require monitoring
New woodlands have low biodiversity
122
Climate active and air quality pollutants?
Black carbon and O3
