Module 3: Finals Version Flashcards
ecological footprint analysis (3)
- standard measure that can be used to related demand for natural resources to the planet’s ability to replenish resources
- results presented as the amount of land and sea area needed to support human populations
what are the main components of the carbon cycle, from smallest to largest (4)
- atmosphere
- land
- ocean
- Earth’s crust
what determines the overall atmospheric CO2 concentration
- the rate of exchanges of atmosphere CO2 with the ocean and terrestrial ecosystems; exchange occurs continuously
carbon cycling in the ocean (3)
- atmospheric CO2 exchanges with oceanic CO2 at the surface through diffusion
- oceanic CO2 reacts to form bicarbonate, allowing oceans to uptake more CO2, but is limited by mineral cation supply from coastal sediment weathering
- concentration of CO2 increases in ocean interior due to two processes: solubility pump ad biological pump
carbon cycling on land (natural) (2)
- CO2 removed from the atmosphere by photosynthesis of plants and stored in organic matter (can be for a long time); about half is released back through respiration
- remainder joins pool of organic matter in soil and eventually returns to atmosphere through soil decomposition (can also take a long time)
carbon cycling on land (human activities) (2)
- combustion of fossil fuels
- land cover change
carbon cycling on land: fossil fuels (2)
- combustion of fossil fuels (coal, oil, natural gas) from million year old organisms as primary energy source
- releases large amounts of CO2 into the atmosphere and alters the natural carbon cycle
carbon cycling on land: land cover change
- land cover change, mainly deforestation, from human population increase and expansion of human settlements
- large areas of native forests cleared and converted into agricultural and urban areas
- as terrestrial carbon storage occurs in forests, land cover changes resulted in net flux of carbon to the atmosphere
what is causing global warming/climate change/changes in Earth as a system
- humans
ecological overshoot (2)
- the phenomenon which occurs when the demands made on a natural ecosystem exceed its regenerative capacity
- occurring right now because of human; our needs surpass the regenerative capacity and resources of a single earth
what are the causal factors to ecological overshoot? (2)
- species/populations have the biological disposition to expand exponentially when possible
- humans have an unparalleled capacity for social learning
causal factors of ecological overshoot: expansion (2)
- species/populations have the biological disposition to expand to fill all accessible habitats AND to use all available resources for continued growth and reproduction
- stock will grow unless a stabilizing feedback mechanism keeps it in check
wha stabilizing feedbacks normally keep populations in check and what does it result in (2)
- population reaches a threshold where it is too big and resource depletion occurs(no more food, space, etc)
- results in loss of infinite growth/ a crash before stabilization of the population size
how are humans bypassing the stabilizing feedbacks that normally act on species populations (4)
- outcompeting other species by modifying the environment
- health care
- social learning
- we construct our reality (laws, politics, economy, etc)
is human population growth an example of a amplifying feedback loop?
- yes: the bigger the population, the more mating that occurs and the more offspring that is produced
causal factors of ecological overshoot: social learning (3)
- we learn from others (both genetically and non-genetically related to us), thus bypassing costly trial-by-error learning
- supports cumulative culture and innovation
- we socially construct our realities and the way we perceive those realities
what is the result of the population growth of humans
- we have a huge (and still growing) capacity for consumption, but Earth did not get any larger; PROBLEM
what fueled the exponential growth of humans
- extensive use of fossil fuels allowed more agriculture mechanization, leading to removal of stabilizing feedbacks due to food and resource abundance
how does technology and efficiency address ecological overshoot
- the though that we can support the growth with efficiency is incorrect; more efficiency will lead to increased consumption due to faster inflow into the stock
symptoms of overshoot: atmospheric CO2 (2)
- increase in atmospheric carbon dioxide and climate change
- 45% increase above pre-industrial levels leads to a change in the chemistry of the ecosphere
symptoms of overshoot: surface temperature
- the average temperature per year is getting warmer
symptoms of overshoot: plunging biodiversity (2)
- human population and economic growth are competitively displacing wild species from their habitats and food sources
- results in extinction and displacement; replacement of wild species with livestock to support humans and room for humans to live
symptoms of overshoot: world energy (2)`
- increase in consumption of all energy types
- positive: renewable energy use is increasing, but this is not the solution if overall energy consumption continues to grow as this will still increase carbon emissions
the boom-bust population cycle (3)
- populations will experience a ‘boom’ when favourable growth conditions occur (humans here right now)
- when nutrients are depleted (unavoidable as we are confined to a finite number of resources on Earth), stabilizing feedbacks will cause the population to go through a ‘bust’
- pattern common to non-human species introduced to a resource-rich system
why can humans avoid the uncontrolled collapse of population (‘bust’) (4)
- high intelligence
- the ability to plan ahead
- the capacity to exercise moral judgement
- empathy/compassion for other people and species
how can humans avoid the uncontrolled collapse of population (‘bust’)
- decrease the overshoot/resource need to be under the carrying capacity of the Earth
project drawdown (2)
- global initiative to rank hundreds of solutions to current climate projections
- aim to show which climate issues are most important to achieve a future point in time when levels of greenhouse gases in the atmosphere stop climbing and start to steadily decline (inflow < outflow)
product footprint
- evaluates life cycle of products and ranks actions
do you personal choices reduce your contribution to climate change
- yes: can be small (upgrading light bulbs, recycling) or large (one less baby, car free life)
why are cars bad for climate change (2)
- the cost to manufacture, refine fuel, run the vehicle, and for maintenance are high; lots of emissions
- more car users take up more space, creating need for more space for roads/parking, creating an increased need to own a car to get to further away places; amplifying feedback loop that requires even more emissions
why is air travel bad for climate change
- a single flight can take up ALL of the suggested yearly emissions (to avoid ecological overshoot) for an individual
why is a plant-based diet good for the environment
- just subbing one plant-based item for a animal-based item can achieve huge emissions reductions and free up cropland
