Intro to Global environment

Question 1

Earth is a closed system

Answer 1

Closed System: the Earth, energy is exchanged with the environment
Energy is exchanged with the outside environment, while matter is not Example: Earth Limited amount of water etc.
Open System: Energy and matter. Both energy and matter are exchanged with the outside environment. Example: Any of the Earth’s spheres

Question 2

The earth system consists of spheres interact via cycles that are
composed of reservoirs, fluxes, inputs and outputs.

Answer 2

Biosphere (Anthroposhere)
Hydrosphere (Cryosphere)
Lithosphere (Pedosphere)
Atmosphere (Troposhere Stratosphere)

Question 3

Perturbations can result in complex, non-linear responses in the system that affect multiple spheres across a wide range of spatial and temporal scales.

Answer 3

Perturbations - Examples
A landslide into a creek
Changes of the Earth’s orbit around the sun
Pollution of a pristine environment
Changes to the CO2 concentration in the atmosphere
Development of agriculture (technolog. advances)
Changes in the economic system

Question 4

Linear and Non-linear

Answer 4

Linear: The magnitude of the response is proportionate to the perturbation
Non-linear: The magnitude of the response is not proportionate to the perturbation

Question 5

feedback loops

Answer 5

Feedback loops: Situations where the response to a perturbation or disturbance includes an effect on the magnitude of the perturbation
Positive Feedback Loops enhance or amplify changes; this tends to move a system away from its equilibrium state and make it more unstable.
Negative feedback is a process that occurs in a feedback loop in which the response to a small disturbance in a system includes a decrease in the magnitude of the perturbation.
can lead to exponential/episodic system responses.