Planetary Boundaries Flashcards
(36 cards)
Planetary Boundary definition
- a threshold value for global processes that are affected by human activity
- crossing these boundaries could generate abrupt or irreversible environmental change
what state is the climate change planetary boundary?
Crossed
what are the causes of climate change?
- rising greenhouse gas levels
- burning of fossil fuels
- deforestation
- leading to global warming
what are the consequences of climate change?
- increased global temperatures
- impacts on wind currents / ocean current / rainfall
- thermal expansion
- melting of polar ice caps
- extreme weather
- habitat destruction reduction in biodiversity
what are some possible remedial measures for climate change?
- reduce fossil fuels -> alternative fuel
- reduce biodiversity
what state is the biodiversity planetary boundary?
Crossed
what are the causes of loss of biodiversity?
- habitat destruction
- deforestation
- coral reef
- hunting (overhunting)
what are the consequences of loss of biodiversity?
- species interact - cannot evolve quickly enough to adapt
- reduction in species extinction
- limits available and potential medicine
what are some possible remedial measures for loss of biodiversity?
- monitor biodiversity
- species conservation
- seed/sperm banks
- education
what is the state of the land use change planetary boundary?
-Crossed
what is the causes of land use change?
- land use change
- for food
- biofuel
- urbanisation
- livestock farming
what are the consequences of land use change?
- exploitation -> biofuel crops take away from food grown to eat
- reduce biodiversity
what are some possible remedial measures for land use change?
- concentrate farming in most high yield areas
- reduce meat consumption
- more efficient crops
what is the state of the nitrate phosphate (biogeochemical flows)
crossed
what are the causes of rising nitrate and phosphate levels
- use of fertilisers containing nitrate and phosphate
what are the consequences of rising nitrate and phosphate levels?
- eutrophication (run off into bodies of water)
what are some possible remedial levels for rising nitrate and phosphate levels
- use less fertiliser
- use organic manure
- rotate crops
what is the state of the ozone planetary boundary?
Avoided
what are the causes of depleting ozone?
- manufacture of CFCs in aerosols refrigerator and coolants etc
what are the consequences of depleting ozone?
- ‘hole’ in the ozone layer
- harmful UV is not absorbed
- DNA mutations
what are remedial measures for depleting ozone levels
- Montreal protocol
what is the stage of the ocean acidification planetary boundary
Avoidable
what are the causes of ocean acidification
- greenhouse gases released from fossil fuels
- CO2 dissolves in seawater forming H2CO3 carbonic acid
- releases H+ ions lowering pH
what are the consequences of ocean acidification?
- reaction of calcium carbonate damages coral arthropod exoskeleton and mollusc shells
- more valuable to predators
