planetary boundaries Flashcards
how many proccesses regulate the stability of the land atmosphere and sea
9
Has the climate change boundary been crossed
yes
What is the earths temperature controlled by
greenhouse gasses in the atmosphere
What is there evidence for between the link of CO2 and temperature
Higher concentration of atmospheric carbon Dioxide is correlated with higher average global temperature
What else does atmospheric temperature impact
wind patterns Ocean currents Rainfall
How does positive feedback occur
there are warmer seas which melt polar ice,
The sea is less reflective than ice so more heat is absorbed so the sea gets even warmer
What is the issue with the increase of atmospheric temperature
Thermal expansion and melted ice running off land raise the average sea level.
Without significant action, a rise of up to 7 m is predicted by 2100.
What was the boundary for atmospheric cabon dioxide
350 ppm
what does ppm mean
parts per million
What are two examples of international agreements to combat climate change
Kyoto protocol
COP21
Kyoto protocol
The Kyoto Protocol, agreed by 84 countries in 1997,
was the first of many major international agreements to address global warming.
It set targets for reducing the greenhouse gases in the atmosphere. Some major polluters did not sign the agreement
COP21
Keep global temperatures ‘well below’ 2.0oC above pre-industrial times and ‘to endeavour to limit’ them to 1.5oC
Limit greenhouse gas emission by human activity to what can be naturally absorbed,
to start between 2050 and 2100 Review each country’s achievements every five years
For rich countries to help poorer nations to adapt to climate change and switch to renewable energy
Has The Biosphere Integrity Boundary been crossed
yes
what has been the route to biodiversity lost
Habitat destruction Populations of living organisms are reduced
Too few individuals in a species remain the survival of the species may be under threat and it may become extinct
Species interact so entire communities come under threat
What are some of the ways to protect species
Monitor biodiversity Species conservation e.g. seed banks, sperm banks
Prohibit international trade in endangered species and their products e.g. ivory
Limit fishing when fish are spawning
Limit logging
Limit the use of agricultural chemicals e.g. fertilisers, pesticides Increase
public awareness
Has The Land System Change Boundary been crossed
Yes
What is the problem with this
Natural ecosystems, including rainforests, have been used for urban development, raising livestock and farming,
including growing biofuel crops this lead to pollutants made from agriculture and other activities further degrade the remaining land
The boundary and how to live within it
no more than 15% of ice free land should be used for crop growing and human habitation
farming concentrated in the most productive areas
people should eat less meat to reduce the area under cultivation
more efficient crop plants should be grown
Has The Biogeochemical Flows Boundary been crossed
yes
How has the balance of chemical elements maintained by natural cycles been disrupted
Fertiliser use (atmospheric nitrogen fixed in the Haber process and phosphorous extracted from rocks)
Agricultural nitrogen fixation
Combustion of fossil fuels and biomass
What are the consequences of this balance being changed
Eutrophication from nitrate and phosphate run off into bodies of water
acidification as excess carbon dioxide dissolves in sea lakes and rivers
what is the consequence of acidification
can cause a disruption of gas exchange in fish and the softening of the shells of molluscs
What is the boundary defined by
no more than 62 million tonnes of nitrogen should be added to the ecosystems each year to prevent disruption of the global nitrogen cycle
Has The Stratospheric Ozone Boundary been crossed
no it has been avoided
