Exam Flashcards
What are the 3 parts of the great acceleration?
- cheap energy from fossil fuels
- abundant natural resources
- global expansion of farmland
How is wealth divided?
- 46% of wealth controlled by richest 0.7%
- 97% of wealth controlled richest 30% (more than 10,000)
How much of worlds population little to CO2 emissions?
Half
How many people in Africa contribute to Co2 emissions?
More than 1 billion people contribute 4%
Is unsustainable resource growth due to population growth of recourse use by wealthy?
Wealthy resource use
How has population in urban areas changed?
1900, 2/10
2010, 5/10
2050, 7/10
How much increase required in calories to feed 9.6 billion in 2050?
69%
How much land is used food?
50% of worlds land
How much does food contribute to GHG?
28%
How much does food contribute to GHG?
28%
What is needed for sustainable intensification of agriculture?
- increase yields
- reduce inputs
- improve soil health
How much warmer is 2021 than pre industrial period?
1.04C
What places contribute most to emissions/
NA - 25%
ASIA - 29%
EU - 22%
Who began tracking CO2?
Charles Keeling 1957-58, South Pole and Hawaii
How has ppm changed in Keeling curve?
315 in 1957 to 415 now
Main GHG and %
CO2 - 66%
CH4 - 16%
N2O - 6%
What is global warming potential (GWP)
compares integrated radiative forcing over specified period 298:25:1
Main sources of CO2
- Electricity and heat (40%)
- Transport (21%)
- Manufacture and construction (16%)
Main sources of CH4
- Agriculture (42%)
- Fugitive emissions (38%)
- Waste (18%)
Main sources of N2O
- Agriculture (82%)
- Industry (9%)
- Waste (5%)
Estimated value of terrestrial ecosystem
$75-85 trillion
What is cultural heritage?
ecosystems have intrinsic values beyond monetary (aesthetic or recreational)
What is global homogenisation of diets?
- Range of crops contributing to national food supply become more similar
- Caused by globalisation and urbanisation
- Increased preference for energy dense food
How has food supply changed?
- supply of oils and meat doubled
- food calorie supply increased 33%
- cereal production increased 3.4x
- fertiliser application increased 9x
How much crop calories go to farm animals?
40%
How much do livestock outweigh wild mammals
14 to 1
Living planet index decline?
68%
How much does land use change contribute to GHG emmisons in food system?
33%
What cause extreme events to become more frequent?
Mean and variance
How has global extreme heat changed?
local record monthly temp extreme now 6x larger than with no climate change (80% new heat from climate change)
How does artic winter affect populations?
- Ice encasement and ice lenses 9rain on snow)
- Food planets inaccessible
- Damages plant (food)
Habar Bosch?
- produces 450 million tonnes of N fertiliser per year
- 3-5% of worlds gas production
- 2% of world energy
Aims of SDG?
17 SDGs
- end poverty
- protect planet
- all people enjoy peace and prosperity
How much calories lost in waste?
2441 daily calories per person
How do we plan to improve resource consumption, from linear to circular economy?
take, make, use, lose
reduce, reuse, recycle
What are co-benefits and trade offs?
Co-benefits - progress of one target enhances progress to another
Trade-off - progress of one target slows progress of another
What is an ecosystem?
physical area covered by groups of organisms experiencing similar environmental conditions (abiotic factors)
What is a biome?
Areas of vegetation characterised by same life form (particular climatic and soil conditions)
What are biotic and abiotic factors?
biotic - organism/organism
abiotic - organism/enviroment
What are the 2 types of interactions?
Trophic - primary producers, consumers, decomposers
Symbiotic - mutualism- parasitism, predation
What is the photosynthesis % efficiency?
5%
What is the land surface energy balance?
In - shortwave solar energy
Out - reflection, evaporation latent heat, sensible heat
What does vegetation control?
Evaporation - trees use more water than grass or soil
Also influences albedo
What is global evaporation?
transpiration through plants accounts for 80-90% of terrestrial evaporation
What are the 3 groups of factors affecting plant distribution?
climatic factors
physiographic factors
edaphic factors
What are climatic factors?
temperature, rainfall, light, wind, humidity
(responsible for regional and global distribution patterns)
What are physiographic factors?
determined by landforms and landscapes
altitude - (lapse rate), -6.5C per 1000m
aspect - direction of slope (influences irradiance received)
What are edaphic factors?
factors associated with soil:
- rooting medium
- source of water
- source of nutrients
What are conditions?
- environmental variables plants respond to
- not consumed
- some may help regulate availability of resources
What are resources?
- consumed by plants
- essential for growth
- different species have different capacities
What is the graph linking species richness and crop mass?
Grimes hump back curve
What is the reservoir effect?
sewer species adapted to grow on acidic soil than neutral
Facts about ocean
71% of world is ocean
average depth = 3,794m
maximum depth = 11,022
What are the major classes of marine life?
Benthic (on or in sea bed)
Demersal (associated with sea bed)
Pelagic (in water column, plankton and nekton)
What are the major classes of marine life?
Benthic (on or in sea bed)
Demersal (associated with sea bed)
Pelagic (in water column, plankton and nekton)
What are phytoplankton?
- overcome coastal dependence by being g small
- occurs through oceans
- responsible for 50% of photosynthesis and oxygen
What is the 2 layered ocean?
- light at the top, nutrients at the bottom
- if ocean was homogenous, life would not persist
What is NASAs MODIS?
- measures Chl a every day
- measures ocean colour
- many in situ measurements
How do we overcome the 2 layer ocean dilemma?
- mix of surface waters by wind
- Coriolis effects caused by earths rotation
- surface currents driven by ocean-atmosphere interactions
- upwelling of nutrient rich deep waters
What are the outcomes of mixed waters?
- patchy, highly structured ocean
- threats follow these boundaries
- marine ecosystems are distinctive
How do we divide up the ocean?
- Horizontally
- Vertically
- biologically
- biogeographically
- Politically
How do we divide up the ocean?
- Horizontally
- Vertically
- biologically
- biogeographically
- Politically
What are the 4 ocean depth zones?
Euphotic (50-100m)
Dysphotic (100-1000m)
Bathypelagic (1000-6000m)
Hadal zone (>6000m), ocean trenches
What are the 3 biogeographic definitions of marine ecosystems?
- Longhurst biogeographical provinces
- MEOW, marine ecoregion of the world
- Biogeography driven by species distribution
What is Longhurst biogeographical provinces?
Ocean divided into 4 biomes based on physical forces regulation distortion of phytoplankton:
- polar biome
- westerlies biome
- trade winds biome
- coastal boundary zone biome
What are Longhurst pros and cons?
- concentrates on planktonic ecosystem and physical oceanographic processes driving it
- large scale ecological studies
- dosent cover significant marine ecosystems or taxa
What is MEOW?
- motivated by conservation concerns
- coastal and shelf areas only
- cover what Longhurst dosent
MEOWs pros and cons?
- designed to be pragmatic and relevant to management and conservation
- good job for coastal and shelf ecosystems
- mot world oceans not covered by this scheme
How many realms, provinces and ecoregion are there?
Realms - 12
Provinces - 62
Ecoregion - 232
What political and management units divide up our oceans?
Large Marine ecosystem (LMEs)
Fisheries management zones
Exclusive economic zones (EEZs), exploration of resource
What is the anthrosphere?
Human component of earth system and its interaction with environment
What dies the earth being a closed system mean?
- resources are finite
- can’t throw things away
- changes in one part will affect other parts
How do we identify complex systems?
Identify components
Determine residence time (how fast elements interact)
Identify deefback loops
What is residence time?
time taken to empty or fill reservoir
steady state, source = sink
What are the 3 main ways energy is transferred on earth?
Radiation, convection and conduction
What is the biggest carbon pool?
1) sedimentary rocks
2) ocean water
3) sea floor sediments
What is the fast carbon cycle?
- carbon on land, in vegetation, soils, peat, freshwater and atmosphere
- 10-10,000 years
What is the slow carbon cycle?
- carbon stores in rocks and sediments
- residence times >10,000 years
What is the CO2 fertilisation effect?
- negative feedback loop
- earth getting greener due to CO2, climate change and nitrogen deposition
What is NPP?
net carbon gained by plants
What is the solubility pump?
- atmosphere has higher concentration than ocean (pCO2)
- CO2 goes down gradient and co2 in water dissolves
(CO2 more soluble in colder waters)