GEO 130 - Earth and Geography: An Introduction

The physical environment (definition)

Matter + energy

Classical elements (Fire, Earth, Water, Air) map to

A form of energy and the 3 states of matter

Four spheres of the Earth system

Atmosphere, Hydrosphere, Lithosphere, Biosphere

Which 3 spheres work together to support the biosphere?

Atmosphere, Hydrosphere, Lithosphere

What makes Earth unique among planets?

It is habitable

Closest potentially habitable exoplanet and its distance

Proxima Centauri b, 4.24 light-years away

Definition of a "system"

A set of interrelated entities working together as a complex whole toward a common function/goal

Four components every system is made of

Inputs, outputs, processes, and feedback

Is Earth an open or closed system?

Both — open to energy, closed to matter

Feedback loop (definition)

Output is fed back into the system as input

Positive feedback

Amplifies an existing tendency

Negative feedback

Counteracts/dampens an existing tendency

A system's state can shift from equilibrium to...

Drastic change / disintegration

Origin of the word "Geography"

Greek: Geo/Gaea (γη/γαια) = "Earth" + graphein (γραφειν) = "to describe/write/map"

First Law of Geography

The relatedness of things is proportional to distance — closer things are more related

What does geography study?

Things on Earth's surface and the relationships among them over space

Geography is defined by its ___, not its ___

Perspective (spatial), not its objective

Two major branches of geography

Physical Geography and Human Geography

Physical Geography focuses on

Earth's physical elements and processes

Two core themes of geography

Pattern (spatial) and process (temporal), often shown with models

What do geographic patterns and processes depend on?

Scale

Why is geography a "real-world science"?

It addresses practical earth problems and human–environment interactions

The "3 S's" of geographic technology

Remote Sensing (RS), GIS, GPS

Remote Sensing (RS)

Captures digital geographic info from remote carriers (satellites, aircraft)

GIS

Geographical Information System — a computerized platform to organize & analyze geographic data

GPS

Global Positioning System — a constellation of satellites + receivers for positioning

Active Remote Sensing

Generates its own energy beams and records the return

Passive Remote Sensing

Records energy coming directly from the ground as affected by sunlight

How does geography differ from a discipline like geology?

Geography is defined by its spatial perspective, not a fixed subject matter — it studies the spatial patterns and relationships of phenomena (including geologic ones), while geology studies Earth's physical materials and processes directly

Scale (in geography)

The level of spatial resolution or generalization at which a phenomenon is studied or represented; the patterns and processes observed can change depending on the scale used

Biosphere 2

An enclosed research facility in Arizona built to test an artificial ecosystem that is materially closed but energy-open; used as a real-world example of open vs. closed systems and scale in geography