Important Scientific Terms and Concepts

[I ran across some lecture notes from when I used to teach Environmental Science classes, between 2001 and 2013.]

"Open Systems" vs. "Closed Systems"

[The textbook definition of a "System" will be added later.]

Open Systems exchange energy, matter, or information between its internal elements and the surrounding environment.  (In terms of living organisms, stimuli detected by various senses provide "information" that influence the organism.)

Nature (as in Climate and Weather) is an Open System, as is every included ecosystem (biome) and every living organism.  And within each system are numerous smaller systems. 

Closed Systems are isolated from their environment, as in a laboratory or computer models.

Inputs - Energy, matter, or information that goes into a system.  "Climate Drivers" are examples of known inputs that influence weather (short term) and climate (a rolling 30-year average).  There may be other inputs that we have not yet recognized.  Inputs can by cyclical or random.

Throughputs - What happens to energy, matter, or information while it is within a system.

Outputs - The results of the passage of energy, matter, or information in a system.  An output for one system may be input for another system.

Feedback Loops are "Nature's Way" of self-regulation of a system.

Positive Feedback Loops happen when a change in a system triggers another change that speeds up the system.

Negative Feedback Loops happen when a change in a system triggers another change that slows down the system.

Synergy - When two or more inputs exaggerate the eventual output of a system.

Antagonism - When two or more inputs cancel (or lessen the effects of) each other.

Time Delay - All systems (and sub-systems) operate at different rates and those rates may be affected by temperature or other inputs.  That is why it may be years or decades between "cause" and "effect".