Planet Boundaries

Which Earth-system processes were identified as crucial for planetary ecosystem and human life?

• (1) Climate change, (2) biodiversity loss, (3) N & P cycles, (4) land use, (5) freshwater use, (6) Stratospheric ozone depletion, (7) ocean acidification, (8) chemical pollution, (9) atmospheric aerosols

• (1) Climate change, (2) biodiversity loss, (3) N & P cycles

• (1) Climate change, (2) biodiversity loss, (3) N & P cycles, (4) the Amazon forest retreat, (5) freshwater use, (6) the ozone layer hole, (7) ocean acidification, (8) micro plastics, (9) CFCs, (10) oil spills

• (1) Climate change, (2) species extinction, including whales, (3) furtive hunting and fishing, (4) species invasion, (5) micro-plastics and the plastic island, (6) CFCs, (7) industrial farms and meat consumption, (8) permafrost thawing, (9) super-resistant bacteria (10) Amazonian rainforest destruction

Tags

NGSS.HS-ESS2-4

NGSS.HS-ESS2-7

NGSS.HS-ESS3-5

Which Earth Systems have already crossed the critical threshold, according to the authors?

• Freshwater use, Biodiversity loss and Land use

• Biodiversity Loss, N cycle and Climate Change

• Climate Change and Biodiversity loss

• Biodiversity loss, Climate Change and Tropospheric ozone layer

Tags

NGSS.HS-LS2-6

The Planet Boundary threshold for Climate Warming is (in atmospheric [CO2] ppmv):

Tags

NGSS.HS-ESS2-6

NGSS.HS-ESS3-5

The Planet Boundary threshold for Climate Warming, as radiative forcing is (in W/m²):

Tags

NGSS.HS-ESS2-4

NGSS.HS-ESS3-5

Which objective evidences did authors use to define CO2 threshold?

• Climate models and Paleoclimate data from the last 100 million years

• Paleoclimate data from the last 100 million years and some Earth sub-systems moving outside of their stable Holocene state (e.g. thawing icebergs and mountain glaciers)

• Paleoclimate data showing that the Earth used to be ice-free from 100 to 50 million years ago, and then, atmospheric CO2 decreased below 450 ppm +- 100 ppm allowing the polar ice sheets to be established

• Climate models, Paleoclimate data from the last 100 million years and some Earth sub-systems moving outside of their stable Holocene state

Tags

NGSS.HS-ESS2-6

Which human activities enhance biodiversity loss, according to the authors?

• Illegal hunting and fishing, Fisheries overexploitation, Industrial farming

• Climate Change, Illegal hunting and fishing, Fisheries overexploitation

• Climate Change, Land Use, Wildfires, Species Introduction,

• Climate Change, Land Use, Wildfires, Fisheries overexploitation

Tags

NGSS.HS-LS2-7

What does "background extinction rate" mean?

• It is the velocity of species extinctions the occurred before the Anthropocene, according to the fossil record and is expressed in number of extinctions per million species per year

• It is the velocity of species extinctions due to human activity

Tags

NGSS.HS-LS4-2

NGSS.HS-LS4-5

What is the Planet Boundary for Biodiversity loss? Are the authors happy with this decision?

• 10 extinctions per million species per year

  YES

• 10 extinctions per million species per year

  NO

• 1 extinction per million species per year

  YES

• 100 extinctions per million species per year

  NO

Tags

NGSS.HS-LS4-5

Which human activities push the most nitrogen and phosphorus cycles to a stress situation, according to the authors?

• Industrial activity

• Cars

• Modern agriculture (fertilisers & leguminous crops)

• Nuclear power plants

Tags

NGSS.MS-ESS3-4

Human processes convert around 120 million tonnes of atmospheric N₂ into reactive N forms. Is it a similar amount to that fixed by all natural terrestrial cyanobacteria fixation? How much should be the Planet Boundary, according to the authors? Are they happy with this decision?

• YES

  35 million T of N/y

  NO

• YES

  35 million T of N/y

  YES

• NO

  25 million T of N/y

  NO

• NO

  25 million T of N/y

  YES