Environmental Systems Flashcards
System
a Collection of Things
that have some sort of relationship
and are a contained within a defined boundary
elements + linkages + boundary (where the system ends)
set of components that function together a a whole
closed system
energy is still exchanged by no material flows in or out
ex: water cycle
isolated system
neither energy nor material flows in or out
continuity equation
input - output is change in reservoir size over time
Steady State vs transient state
the inputs equal the outputs
inputs do not equal outputs
- something is increasing (more coming in) or decreasing (more going out)
can be in virtual steady state over certain time scales
Residence Time
= reservoir volume/flow rate
how long a substance remains in a reservoir
Stock of pollutant
= residence time x flow rate
flow rate
= volume / residence time
ins - outs
volume of reservoir
flow rate * residence time
