Lecture 3 - Feedbacks in Global Systems Flashcards
1
Q
positive coupling
A
positively, directly correlated
2
Q
negative coupling
A
negatively, inversely correlated
3
Q
negative feedback loop
A
negatively and reciprocally correlated
4
Q
albedo
A
reflectivity of a surface, the fraction of total sunlight reflected from a surface ex.) grass 0.2 - 0.3 forest 0.05 - 0.1 snow 0.8 - 0.9 thick cloud 0.7 - 0.8
5
Q
example of a positive feedback system with positive and negative couplings
A
global mean temp, continental snow and ice cover, planetary albedo
6
Q
example of a negative feedback loop
A
predator and prey populations
7
Q
stable equilibrium state
A
ball in a valley between two hills, can withstand some disturbance and the ball will fall back down the hill/return to the mean
8
Q
unstable equilibrium state
A
ball on top of a hill
9
Q
James Lovelock
A
- atmospheric chemist at NASA
- Why has Earth‟s surface temperature remained in steady state for 3.6 billion yrs, while solar radiation has increased by 25%?
- Gaia Hypothesis
- Daisy World
10
Q
Gaia Hypothesis
A
Like an organism, the Earth is self-regulating/homeostasis
11
Q
Daisy World
A
- Planet imagined to test Gaia Hypothesis
- daisies affect (lower) surface temperature because the reflect the light
- temp and photosynthesis
