global environment week one

global environment

the systems that make our planet

hydrosphere

global water cycle moving from abiotic to biotic reservoirs, the bodies of water that cycle heat energy and nutrients across the planet - the global temp allows water to exist in ice liquid and gas)

atmosphere

maintains temp of the planet, transfers heat and rain, provides elements for respiration of bio life

lithosphere

biogeochemical cycles to ensure elements are available for life instead of locked in rock or gas

biosphere

role of life interacting with abiotic processes, shaping climate for better or worse

dynamic environment

self regulating climate over long time, dramatic changes like snowball earths and hothouses

system

mutually interaction components in a boundary, no part of earth systems are isolated. elements, linkages, purpose

elements/components

matter or energy (atmosphere/land) or abstract (values, ideas), can be under multiple factors indirectly and directly

linkages/couplings

relationships that link componennts (land-ocean-atmosphere)

boundaries

where system ends, can be easy or arbitrary

porous boundary

allows for input and output, like a lake with external influences

non-porous boundary

rare, hydrocycle is almost closed bc of limitied water exchange

simple system

few linear relationships and outcomes are predictable

complicated system

any branching linear relationships, few loops and predictable if we are careful (space flight)

complex systems

many non linear, loops, resilient to change but have surprises and subsystems

qualitative system

lined concepts that are material/immaterial

quantitative system

measurable quantities of components and transfers (math)

element dynamics

input I (sum of flow in), element E (quantity in reservoir), output O (sum of flow out), E is units, I and O are units per time

change in E/change in time

=I-O, change in state of component depends on balance of In and Out

steady state

I=O, often only true on averages (may vary around a mean), zooming out to thousands of years

transient state

I>O or opposite, true even if u zoom out to see constant zig zap

mean residence time

average time matter/energy remains in E (E/O when transient) like bathtub residence time is content/output rate to show system dynamics like water vapour in the atmosphere

positive linkage

change in first is same sign of change in second

positive feedback loop

changes are amplified as all signs are the same

negative linkage

signs are different between elements

negative feedback loop

changes are diminished when it gets back to first item

negative feedback loop dominance

when issues occur, system will return to original state for stable equilibrium

positive feedback loop dominance

when issues occur, system will move further from original state towards unstable equilibrium

global equilibrium

most systems are quasi-equilibrium, stable state, with negative feedback loop dominance

tipping points

when positive feedback loops start to win, system shifts rapidly, concerning (too much greenhouse gas might cause it easier for there to be more until irreversable positives overtake negatives), we might not light new equilibrium past the point