Impacts Exam Flashcards
Brief timeline of earth and the human activity on it
World 4.5 bn years. To 544m not very much happened. Then ‘Cambrian explosion’ = big explosion of diversity of life, animals and plants.
From there we have had various periods and epochs, up until most recent; Holocene 0.01 m which was due to agricultural expansion, followed by a mining expansion.
On top of the Holocene, geologists are now uniformly agreed since 2017 that we have entered a new epoche “ANTHROPOCENE”.
- Due to changing surface of the planet; our impacts penetrating layers of the earth where our influence now spans from space to crust (planetary boundaries) – plastics, fly ash, metals, pesticides, GHG concentrations.
Our impact of time and result in environment?
We basically arrived 15 min to midnight, yet changes to the natural environment:
- Land use intensity, warming planet, raised sea levels, eroded ozone layer, acidified oceans, increased rate of extinction, mining activities alone move more sediment than all world’s oceans.
Meanwhile for humans: human life expectancy and living standards are rising = at odds – time scales – we haven’t caught up.
How do we measure the human impact on the planet?
- Human footprint
- Burden of planetary illness
- Planetary boundary approach
HUMAN FOOTPRINT?
Multidimensional index of human pressure on planet.
Broken up into 823 ecoregions of which majority degraded and footprint increased.
Burden of Planetary Illness?
= indicators of our influence
- POPULATION: Took 200,000 years to get to 1st bn in 1804 – now adding 1bn every 11-13 years.
- CONSUMPTION: 20kg fish; 40kg meat/year
- LAND: 320 kg grain = 1% soil lost/year
- Every meal = 10kg of soil = 35 football fields forest lost/min
- Animals: 6th mass extinction; 8 species per hour and 58% decline in vertebrate abundance.
Planetary Boundary Approach?
“Safe Operating Space” = based on idea of “Planetary boundaries” = space to crust human influence: the layers naturally create a safe operating space for us, but the extent to which we can manipulate these before it falls away is questioned.
- This conceptual framework shows us safe operating space, zone of uncertainty, position of threshold and areas of high risk. You have:
- X axis: control variable (pertubation)
- Y function for that system.
- We monitor to see what happens when we mess with things – tipping points, vs. diminishing functions of a system.
The 7 planetary boundaries?
(these are the big systems we are thinking about) – and some we can’t yet measure. Climate change is only 1 of these.!!
Red (high risk zone)
- Biochemical Flows
- Biosphere integrity – genetic & functional diversity
Yellow (uncertainty):
- Climate Change
- Land-system change
Green – safe still
- Freshwater use
- Ocean acidification
- Stratospheric ozone depletion
Climate change is one result of our human influence, which exacerbates other underlying conditions of our other impacts on the planet. E.g. extinction of species is due to land use change rather than climate change.
World Economic Forum top 10 impacts and Likelihood Risks for Global 10-year time horizon?
Of the top 10 global risks in terms of likelihood: 1) Conflict 2) extreme weather 7) Failure Climate Change
Of the top 10 global risks in terms of impact: 1) water crisis 2) disease 3) weapons mass destruction 4) conflict 5) failure climate change.
Definition climate change?
A change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer.
- due to natural internal processes or external forcings
- modulations of the solar cycles
- volcanic eruptions
- anthropogenic impacts on the atmosphere or in land use
UNFCC specifies in its definition the HUMAN influence: “a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition (above and beyond) to natural climate variability observed over comparable time periods.”
Main trends of Climate Change:
Sea ice is melting, C02 concentrations, surface temp; heat content upper ocean; sea level; extreme events (mean/variance); unequivocal human influence.
Definition of Impacts?
Effects on:
- natural and human systems of extreme weather and climate events and of climate change.
- lives, livelihoods, health, ecosystems, economies, societies, cultures, services, and infrastructure
due to the interaction of climate changes or hazardous climate events occurring within a specific time period and the vulnerability of an exposed society or system.
Also referred to as consequences and outcomes.
Physical impacts: subset of climate change impacts on geophysical systems, including floods, droughts, and sea level rise
Definition of Hazard?
The potential occurrence of an event or trend or impact that may:
- cause loss of life, injury, or other health impacts
- damage and loss to property, infrastructure, livelihoods, service provision, ecosystems, and environmental resources.
Definition of Exposure?
The presence of something (e.g., people, livelihoods, species or ecosystems, environmental functions, services, and resources, infrastructure, or economic, social, or cultural assets) in places and settings that could be adversely affected.
Definition of Vulnerability?
The propensity or predisposition to be adversely affected.
- sensitivity or susceptibility to harm
- lack of capacity to cope and adapt.
Definition of Risk?
The potential for consequences where something of value is at stake and where the outcome is uncertain recognizing the diversity of values
- often represented as probability of occurrence of hazardous events or trends multiplied by the impacts if these events or trends occur
- results from the interaction of vulnerability, exposure, and hazard.
Definition of Adaptation and the two types?
process of adjustment to actual or expected climate and its effects.
- seeks to moderate or avoid harm or exploit beneficial opportunities.
- may facilitate adjustment to expected climate and its effects.
Incremental adaptation: Adaptation actions where the central aim is to maintain the essence and integrity of a system or process at a given scale.
Transformational adaptation: Adaptation that changes the fundamental attributes of a human or natural system.
Definition of Resilience?
Capacity of social, economic, and environmental systems to cope with a hazardous event or trend or disturbance, responding or reorganizing in ways that maintain their essential function, identity, and structure, while also maintaining the capacity for adaptation, learning, and transformation.
How do we know and keep track of everything? Evidence and Communication?
Developed a calibrated language that communicates the strength of scientific understanding, including uncertainties and areas of disagreement
- Each finding is supported by a ‘traceable’ account of the evaluation of evidence and agreement
- Virtually certain = 99%; Extremely likely = 95%; Very likely = 90%; Likely 66%; More likely than not = 50%
What is Climate Change awareness like?
- High levels in developed world (Europe, Japan, America)
- Never heard of in developing (Africa, Asia, Middle East) – but here perceived biggest threat.
What happens when you move from Climate Change trends to Impacts? Evidence of impacts?
- Becomes less and less scientific – more qualitative matters of opinion, which is why IPCC ranks everything and why we need the calibrated language.
- Large growth in evidence, some sectors more than others due to more published material & searches; especially for natural and human systems – deviations from historical conditions
- Still limited robust attribution studies and meta-analyses that link biological and physical responses to anthropogenic climate change
- “Detection of impacts” = evidence for whether a system is changing beyond a specified baseline that characterizes its behaviour in the absence of climate change
- Why detection and attribution are so important
How can we detect and attribute/what do we look at?
Assessing the causal relationship between one or more drivers and a responding system by direct and indirect links.
Earth system separated into three components: Climate, Natural and Human. Differentiate between climate change impacts (easier) and anthropogenic climate change impacts (more difficult).
2 broad approaches: pattern analysis and regression analysis – huge uncertainty components – big focus to try and capture, hugely challenging problem.
What are the main challenges related to detection and attribution?
- Observations, 2. Process understanding, 3. Need high quality, 4. long-term data, 5. Processes can be non-linear (e.g., thresholds), 6. local and non-local (both space and time), 7. Based on “synthesis of findings in the scientific literature” = Find and correct potential biases (IPCC no own research).
What are the main observed impacts denoted by the IPCC?
IPCC synthesizes finding in a massive tabulation exercise where they rank everything by confidence, likelihood, attribution and trend.
- MAIN IMPACTS: GHG; Global mean surface temp; GMST - top of the list; thereafter follows sectoral impacts. Also geographical regions.
What are the sectors impact assessments are broken down into? (10)
Freshwater Resources, Terrestrial and freshwater ecosystems, Coastal and low lying systems, Marine systems, Food security and food production systems, Urban system, Economic sectors and services, Human health, Human security, Livelihoods and poverty
Observed Impacts for Sector: Freshwater Resources?
- Permafrost warming and thawing in high-latitude regions and in high-elevation regions (high confidence)
- Changing precipitation or melting snow and ice are altering hydrological systems, affecting water resources in terms of quantity and quality (medium confidence).
- Glaciers shrinking almost worldwide (high confidence), affecting runoff and water resources downstream (medium confidence)
No evidence that surface water and groundwater drought frequency has changed over the last few decades, although impacts of drought have increased mostly due to increased water demand.
Projection difficult due to multiple stressors. Impacts will depend on policies, prices & rules for operating complex system + science and data.
Global supply of freshwater?
Saltwater = 97.5%; Freshwater = 2.5%.
Total usable freshwater supply for ecosystems & humans = 1% of freshwater resources = 0.01% of all water! – 70-92% is used for growing food and raising animals (30%) (bovine, sheep, pig). Water footprint of animal > crop same nutritional value + 40% cereals used for food = Average diet = 3000-5000 L/day.
Different regions = different evaporation & runoff = uneven distribution of freshwater + no management of rivers & lakes as cross many borders. Millennium goal not reached by Africa & Arab. Asia uses most. Virtual water (hidden in exports) = Asia, Africa.
Threats to freshwater resources?
Growing population, diminishing resources. If everyone lives as in UK = 3 plants to support us.
Multiple stressors: Pollution (growing demand but pollution w/o regulated disposals), CC, species invasion (algea/insects), overuse (Mekong river supports 6 countries = ½ pop fish; ½ rice; 1/3 GDP) and poaching + river fragmentation (dams, downstream = ecosystem impairment, collapsed fisheries) land use changes and habitat loss;
Global biodiversity loss is inevitable and water stress in Europe by 2080 + effects of water cycle feedback system.
Adaptation necessities & policies to manage freshwater scarcity?
Flood defenses, cooperation or conflict (fishing pollution, flood control, water utilization, hydro).
Need:
- Need science to underpin policy decisions.
- Global bodies uniting to address global issues
- Demand related shifts - cutting back on agriculture (water productivity) – no policy addresses this.
Observed Impacts for Sector: Terrestrial and freshwater ecosystems?
- Shifting geographic ranges, activities, altered abundance (high confidence). Increased tree mortality.
- Most recent observed terrestrial species extinctions have not been attributed to climate change (high confidence)
- Increases in the frequency or intensity of ecosystem disturbances such as droughts, wind storms, fires, and pest outbreaks (medium confidence).
- Contributed to the extinction of some species (medium confidence)
How do we measure how CC impacting the biological world?
Difficult for us know assess impacts/adaptaion necessary when we are uncertain about observations but: we broadly classify into 4 categories/processes (connected) with their own organising units:
- Organisms: evolution (genetic diversity), physiology (activity rates), morphology (body size & shape); CC = reduction in body size; adopting thermal; hybridization.
- Population: abundance, migration, phenology (timing in relation to climate); CC = 80% population reducing size of pop; timing of life-history processes (budding, spawning, migration).
- Species: distribution habitat quantity/quality, extinction; CC = (tropicalisation: warmer = tropical species come; and borealization – pine forest going into tundra); things are moving!! – up mountains etc. Background extinction rate = 1000x faster in our era than in the past.
Extinction: 7.9% due to CC; RCP 8.5 = 16% - Communities: biomass, species interaction, ecosystems; CC = changes in behaviour, processes; ecosystem invasion and species competition.
What is the other key driver impacting the biological world?
LAND USE = one of key drivers of biodiversity loss and ecosystem change – greatest present concern; 32% of species richness = attributable to land use.
Fisheries = Asia 7m tonnes, Africa: 3m tonnes. Employs 41m people worldwide. Biodiversity – overriding conservation priority; foundation of food ecosystem on which the rest of the food chain relies. 20% of freshwater fish is vulnerable, endangered/extinct.
Not independent of CC; depends on future scenario – some strategies for mitigation have worse effects on biodiversity: RCP – 2.6 = 2nd worse biodiversity outcome! (vegetation for biofuel).
What are the results of CC on the Biological World?
82% of 94 processes that were looked at show response to CC across the 4 broad categories with only 1 degree warming. And probably very conservative! (holes in science & interconnection of processes)
Interesting because: connection between human health & environment – foundation of our society = ecosystems:
- Ecosystems accumulating stress
- Compromised ecological processes
- Direct and interactive impacts
- Diminished resilience
- Leads to ecological regime shifts & ecosystem function (coral => algea; tundra => boreal)
- Implications for human safety – strong evidence for societal collapse.
Monetary measurements of Biological World – Natural Capital?
Value of ecosystem services (natural and public good):
1999 = 30tr/year
2014 = 130 tr/year
4-20 tr lost during this period during due to ecosystem degradation
GDP: only half of what ecosystems are providing; losing 1/3-1/5 of GDP due to ecosystem degradation.
Observed Impacts for Sector: Coastal and low lying systems?
- Sensitive to sea level, ocean temperature and ocean acidification (very high confidence)
- Coral bleaching and species range shifts due to change in ocean temperature = 60% died in 2016 – as CC amplified el Nino.
Impacts of climate change are difficult to identify given other human-related drivers (e.g. land use change, coastal development, pollution)
Observed Impacts for Sector: Marine systems?
- Shifts in the abundance, geographic distribution, migration patterns, and timing of seasonal activities of marine species (very high confidence)
- Changing interactions between species, including competition and predator-prey dynamics (high confidence).
- Altered ecosystem composition (high confidence)
- Reduction in maximum body sizes (medium confidence).
- Species replacement, bleaching, and decreased coral cover causing habitat loss.
- Responses to ocean acidification less clear, not yet outside natural variability, influenced by other factors
- “dead zones” are increasing in number and size
Observed Impacts for Sector: Food security and food production systems?
- Reduced crop yields more common than increases; extreme daytime temperatures (~30C) are influential (high confidence).
- Wheat and maize yields reduced (less so for soy and rice (medium confidence).
- Rapid food and cereal price increases following climate extremes (medium confidence)
- CO2 has stimulatory effects on crop yields in most cases, and elevated tropospheric ozone has damaging effects – other consequences weight out these benefits => net losses. Other than soy – will do well.
Key considerations for food security relating to CC:
Production aspects of food security rather than access most important
- Production and price are most important/key = these lead downstream to food security. We can stand 1 hit to staple food/year before affects human health/livelihoods.
KNOW: population rising, yields falling; CONTROL: climate/yields; RESEARCH: New varieties/new farming practices.
Long Run/Short run links between CC and food availability
Long run: warming climate, responses to climate initiatives (agrofuels), gov. policy.
Short run: climate events, droughts, heat wave, floods => food insecurity exacerbated by CC => to market & gov. responses.
Food Security Definition?
“… a situation that exists when all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life”
Where are people most affected by food insecurity?
Mainly Africa by population proportion (27%); South Asia in absolute numbers (300m undernourished) – closely linked to poverty: multiplier: low yields for farmers, low purchasing power for consumers, high proportion of income spent on food.
Not evenly spread across globe – high latitude countries, UK & China are benefitting – already less insecure.
Dynamics of a food crisis & systemic risk?
Historically local & linked to weather shock, isolated = wait it out/food aid/storage
Now: still weather shocks – but complex, interconnectedness of markets => rapid price increases. (long & short drivers => panic & strategic responses) => export restrictions, stockpiling & speculation instead of shipping surplus to affected => food price shot up.
What could be blamed for the 2008 food crisis?
Biofuels: forced global food prices up by 75% - raising target would force up. 5% diversion of worlds cereal to agrofuels + increasing meat consumption in Asia.
Falling stocks: carry-over stocks grain always basic indicator of food security - falling since 200. Underinvestment in agriculture when prices were low.
Export restrictions: Rice - suspicion of shortages => shortages by hoarding & panic buying (increased demand) => food prices spiked.
- All resulted in great food price volatility + speculation on commodity exchanges & initial shock of disrupted weather. Too much market, not enough control.
Adapting to CC in terms of food security?
Reduce volatility by markets & storage – spread volatility across time and space. Preventing future volatility:
- Storage: emergency reserves, int. coordinated grain reserves.
- Info & Coordination: more and better information on storage – food agency report on stocks & cooperation.
- Trade facilitation: int. grain clearing agreement, prevent export bans, food import financing
Link between bad governance and food security?
“most recent famines have been caused not because food wasn’t available but because of bad governance — institutional failures that led to poor distribution of the available food, or even hoarding and storage in the face of starvation elsewhere. “No substantial famine has ever occurred in any independent and democratic country with a relatively free press.”
Observed Impacts for Sector: Urban systems?
- High proportion of the population and economic activities at risk are in urban areas
- Rapid urbanization and growth of large cities creates highly vulnerable urban communities, often living in informal settlements, exposed to extreme weather (medium confidence) - Today 5/10 live in urban; 2050 = 7/10.
- Urban areas often exacerbate climate changes, including extreme weather events – urban island effect.
Risks from CC and Urbanization?
Heat – R: heat island, cooling demand, air pollution, ozone ground level. ER: Complex interaction of heat stress, air pollution & social vulnerability.
Drought, water supply, wastewater & sanitation – electricity shortages, conflict end users water related disease, food price & insecurity,
+ energy supply, transport & telecommunication; housing; infrastructure; health & social services; poverty & discrimination exacerbates vulnerabilities.
Increased concentration of people in urban centers 2010 => 2050; = more concentrated risks + greater opportunities for benefits/adaptation.
Adaptation Opportunities in Urbanization?
Economies of scale; density means more intense use of infrastructure; acceleration of economic activity (higher productivity); creativity from diversity & interdependence.
- Addressing CC by urban planning has major co-benefits health
- Air pollution (9th highest risk factor disease globally); physical inactivity pandemic (10 diseaseth); traffic injuries (8th cause of death).
Options:
- Dense and mixed land use (active forms of transport – walking, cycling, public transport) – tradeoff density and pollution!
- Greenspaces: reduce heat island, energy consumption, improve drainage, food supply, improve biodiversity & social capital & physical activity.
Observed Impacts for Sector: Economic sectors and services
- Socioeconomic losses from flooding have increased, mainly due to greater exposure and vulnerability (high confidence)
- Flooding can have major economic costs (robust evidence, high agreement)
- Affected insurance systems (robust evidence, high agreement)
- Economic losses due to extreme weather events have increased globally (low confidence in attribution to climate change)
Global economic impacts are difficult to estimate + not all key economic sectors and services have been subject to detailed research
