Comprehensive Geography: Physical Systems, Mapping, Atmosphere, and Seasons

Geography

Study of the spatial relationships between people, places, and environments.

Physical geography

Branch of geography focused on natural Earth systems (atmosphere, hydrosphere, lithosphere, biosphere).

Spatial perspective

Analyzing where things are, why they're there, and how they're connected.

Spatial scale

Geographic extent (local, regional, global).

Temporal scale

Time frame of processes (seconds to millennia).

Solar energy

Energy that drives work in the Earth-atmosphere system (insolation).

Earth systems

Atmosphere, lithosphere, hydrosphere, biosphere.

Positive feedback

Amplifies change (e.g., ice melt → less albedo → more warming).

Negative feedback

Stabilizes a system (e.g., cloud cover reducing surface heating).

Inductive reasoning

Most used type of reasoning in physical geography (observations → general principles).

Latitude & Longitude

Angular system for absolute location (lat = N/S of equator, long = E/W of prime meridian).

GPS

Satellite-based positioning system.

Maps

2D representations of Earth's surface.

Map projections

Methods to display curved Earth on flat maps (always distort shape, area, distance, or direction).

Map scale

Ratio of map distance to real distance.

Representative fraction

1:24,000.

Large scale

Shows small area in detail.

Small scale

Shows large area with less detail.

Isolines

Lines of equal value.

Isotherms

Lines of equal temperature.

Contour lines

Lines of equal elevation.

General reference maps

Show natural/cultural features.

Thematic maps

Emphasize one theme (e.g., population density).

Remote sensing

Collecting info without direct contact.

Passive sensors

Detect natural energy (e.g., satellite photos).

Active sensors

Emit energy and measure return (e.g., radar, Lidar, sonar, Doppler, drones).

GIS

Computer-based mapping/database system for spatial data analysis.

Homosphere

Up to 80 km, well-mixed gases.

Heterosphere

Above 80 km, layered by molecular weight.

Permanent gases

N₂ (78%), O₂ (21%), Argon (0.9%).

Variable gases

Water vapor, CO₂, CH₄, O₃.

Particulates

Dust, ash, pollen, salt, smoke, aerosols.

Atmospheric pressure

Force of air molecules on Earth's surface; average = 1013.25 mb (29.92 in Hg).

Atmospheric pressure change with altitude

Decreases rapidly with height.

Ideal Gas Law

Relationship between pressure and temperature; warmer air = lower density and pressure expands.

Troposphere

The lowest layer of the atmosphere where weather occurs.

Stratosphere

The layer of the atmosphere above the troposphere, containing the ozone layer.

Mesosphere

The layer of the atmosphere above the stratosphere.

Thermosphere

The layer of the atmosphere above the mesosphere, characterized by high temperatures.

Ionosphere

A region of the atmosphere between 60-1000 km that absorbs harmful radiation, reflects radio waves, and produces auroras.

Anthropogenic air pollution

Human-caused pollutants, mostly from fossil fuel combustion.

CO₂

A greenhouse gas that contributes to global warming.

CO

A toxic gas produced from incomplete combustion.

NO₂

A brown haze gas resulting from combustion processes.

N₂O

A long-lived greenhouse gas produced from fertilizers and livestock.

O₃ (tropospheric)

A harmful component of photochemical smog affecting lungs and plants.

SO₂

A gas from coal and volcanoes that forms acid rain.

Particulates (PM2.5 & PM10)

Small particles like ash, dust, and smoke that are harmful to lungs.

VOCs

Volatile organic compounds, hydrocarbons from vehicles and industry.

CH₄

Methane, a strong greenhouse gas.

Air Quality Index (AQI)

A measure by the U.S. EPA that varies seasonally, indicating air quality.

Urban heat island

An effect where cities are hotter due to human activities and infrastructure.

Stefan-Boltzmann Law

A principle stating that hotter objects emit more energy.

Wien's Law

A law stating that hotter objects emit radiation at shorter wavelengths.

Shortwave radiation

Solar radiation including UV, visible, and near IR.

Longwave radiation

Earth's re-radiation in the thermal infrared spectrum.

Albedo

The measure of reflectivity of a surface, with snow having high (80-95%) and asphalt low (5-10%) albedo.

Greenhouse gases

Gases that trap outgoing longwave radiation, maintaining Earth's average temperature.

Latitudinal radiation differences

The concept that tropics have a surplus of energy while poles have a deficit, balanced by winds and ocean currents.

Rotation

The spinning of Earth on its axis approximately every 24 hours.

Revolution

Earth's orbit around the Sun, taking about 365.25 days.

Tilt

The angle of Earth's axis (23.5°) that affects seasonal changes.