Planetary Boundaries Flashcards
Biosphere Integrity control variables
Loss of genetic diversity
Loss of functional diversity
Loss of genetic diversity
Genetic diversity provides the potential for species to adapt to new conditions brought by changes in Earth systems.
Measured by number of extinctions per million of species per year: E/MSY
Biosphere Integrity definition
The biosphere depends on and is influenced by all Earth system processes. Feedback cycles within the biosphere affect the flow of material and energy and help to regulate the Earth system and provide resilience. Core PB.
RED
Loss of functional diversity
The filling of functions (niches) within the biosphere. To have a healthy planet, all species need to fill specific roles in the environment.
NOT YET QUANTIFIED
Loss of genetic diversity: boundary and current value
Boundary: 10 E/MSY
Currently: >100 E/MSY
Core Planetary Boundaries
Climate change + Biosphere Integrity
Climate Change: Control variables
Concentration of CO2 in the atmosphere
Radiative Forcing
Climate Change: definition
Includes the change in temperature, weather patterns and more. Core PB.
RED
Atmospheric CO2 concentration: definition
Concentration of CO2 in the atmosphere. CO2 is the most important greenhouse gas: which impact the Earth’s temperature
Radiative Forcing: definition
The rate of energy change per unit area of the globe as measured at the top of the atmosphere, relative to 1750 (pre-industrial revolution). Equivalent to one light bulb being turned on per square meter.
Measured in: W/m^2
Atmospheric CO2 Concentration: Boundary and Current Value
Boundary: 350 ppm
Currently: 428 ppm
Radiative Forcing: Boundary and Current Value
Boundary: 1 W/m^2
Currently: 3 W/m^2
Novel Entities: definition
Include pollution from plastics and other man made materials that have been introduced by human activity.
RED
Novel Entities: control variables
None clearly defined, some suggested:
- Production of materials
- Release of materials
- Toxicity/disturbance to biosphere integrity of materials
Biogeochemical Flows: definition
Pathways between living organisms and the environment. Specifically nitrogen and phosphorus flows.
RED
Biogeochemical Flows: Control variables
Nitrogen fixation rate
Phosphorus flow to erodible soils
Nitrogen fixation rate: definition
Industrial and intentional biological fixation of nitrogen
Phosphorus flow to erodible soils: definition
Flow of phosphorus from freshwater systems into the ocean globally, and flow from fertilizers to erodible soils regionally.
- Phosphorus comes from specific rocks and once fixed cannot be returned to original state
Nitrogen fixation rate: Boundary and current value
Boundary: 78 Tg N/yr
Currently: 248 Tg N/yr
Phosphorus flow to erodible soils: boundary and current value
Boundary: 7 Tg P/yr
Currently: 11 Tg P/yr
Ocean Acidification: definition
Increased CO2 concentration in oceans is linked to a drop in pH. Affects marine life, specifically shellfish and their shell production. GREEN
Ocean Acidification: Control variable
Aragonite saturation state, relative to pre-industrial levels (%)
Aragonite saturation state: definition
ocean surface saturation state of carbonate ions with respect to aragonite
Ocean acidification: boundary and current value
Boundary: >80%
Currently: 84%
Freshwater use: definition
Freshwater use is blue water from rivers, lakes, reservoirs, and renewable groundwater stores, as well as green water from terrestrial precipitation, evaporation, and soil moisture. Disruptions and/or changes in the environment can impact freshwater use.
ORANGE
Freshwater use: control variables
Human induced disturbance to blue water flow (%)
Human induced disturbance to green water availability (%)
Human induced disturbance to green water availability: definition
Green water includes terrestrial precipitation, evaporation, soil moisture, and water available to plants. Human disturbances to green water available to plants can have severe consequences for several terrestrial biosphere processes.
Human induced disturbance to blue water availability: definition
Blue water is surface and ground water. The control variable for this Earth system looks at how humans have changed streamflow over ice-free land from the pre-industrial state.
Freshwater use: Boundaries and Current values
Blue water:
Boundary: 10%
Currently: 18%
Green water:
Boundary: 11%
Currently: 16%
