Geography: Earth’s Surface, Climate, and Human Impact
Geography as a Scientific Discipline
Geography is the science of Earth’s surface, including land and spatial relationships.
Geographical Coordinates
Coordinates pinpoint locations on maps, plans, or Earth’s spherical surface using a Geographic Information System (GIS). Latitude measures North or South, while longitude measures East or West.
Map Scales
Numeric Scale: A fraction showing the relationship between map length and real-world length.
- 1/100,000: 1 cm on the map equals 1 km in reality.
- 1/250,000: 1 cm on the map equals 2.5 km in reality.
- 1/5,000: 1 cm on the map equals 50 m in reality.
Graphic Scale: A graduated line representing real-world distances. Its size changes proportionally with the map’s size.
Maps are categorized by scale:
- Very Small/General Scale: Over 1/1,000,000 (General Maps)
- Small Scale: Between 1/400,000 and 1/1,000,000 (Geographical Maps)
- Medium Scale: Between 1/25,000 and 1/200,000 (Topographic Maps)
- Large Scale: Between 1/100 and 1/10,000 (Technical Drawings)
A larger denominator indicates a smaller scale.
Earth’s Atmosphere and Climate
Atmospheric Layers
- Troposphere: The lowest layer, containing 80% of atmospheric gases and most water vapor. Weather phenomena occur here. Temperature decreases with altitude (about 6.5°C per km).
- Stratosphere: Contains the ozone layer, which absorbs UV radiation.
- Mesosphere: Contains ice and dust particles. Meteors burn up in this layer.
- Ionosphere/Thermosphere: Where auroras occur.
- Exosphere: The outermost layer.
Climate vs. Weather
Climate: The long-term atmospheric characteristics of a location.
Weather: The short-term state of the atmosphere at a specific time and place.
Elements of Climate
- Precipitation: Liquid or solid water falling from the atmosphere.
- Temperature: Determines the heat of a body.
- Atmospheric Pressure: Pressure exerted by the atmosphere due to gravity.
- Humidity: Amount of water vapor in the air.
- Latitude, Continentality, Relief: Factors influencing climate.
Types of Precipitation
- Convective: Caused by rising warm air.
- Frontal: Due to the collision of air masses.
- Orographic: Caused by air rising over mountains.
Climate Types
Arid: Characterized by water deficit. Example: Southeastern Iberian Peninsula.
Mountain: Temperature decreases with altitude. Example: Pyrenees.
Mediterranean: Temperate with dry summers. Example: Most of the Iberian Peninsula.
Oceanic: Temperate with abundant rainfall. Example: Cantabrian Strip.
Subtropical: Warm temperate, influenced by trade winds. Example: Canary Islands.
Urban: Higher temperatures due to human activity. Example: Madrid.
Continental: Large temperature range. Example: Duero Basin.
Desertification: Transformation of land into desert. Example: La Mancha.
Drought: Significantly less rainfall than normal. Example: Southern Spain.
Geological Processes
Rock Types
- Igneous: Solidified magma. Example: Granite, basalt.
- Sedimentary: Formed from deposits of other rocks. Example: Sandstone, limestone.
- Metamorphic: Altered by heat and pressure. Example: Slate, marble.
Tectonic Activity
Earth’s crust consists of moving plates, causing earthquakes and volcanoes.
Landform Modeling
- Glacial: Erosion by ice. Example: Pyrenees.
- River: Erosion by water. Example: V-shaped valleys.
- Coastal: Erosion by waves. Example: Beaches.
- Wind: Erosion by wind. Example: Dunes.
- Karst: Erosion of limestone. Example: Caves.
Human Geography
Population
- Population Pyramids: Expansive, regressive, stationary.
- Economic Sectors: Primary, secondary, tertiary, quaternary.
Migration
- Intercontinental: Migration to other continents.
- Pendular: Daily movement between home and work.
Economic Activities
- Industrial Relocation: Moving production to another location.
- Alternative Energy: Replacing oil with other energy sources.
Tourism
- Mass Tourism: Large-scale tourism.
- Alternative Tourism: Ecotourism, adventure tourism, etc.
Environmental Issues
- Acid Rain: Caused by sulfur and nitrogen oxides.
- Recycling: Reusing materials.