Chapter 4. Physical Geography

Earth’s structure and plate tectonics. Earth has a crust, mantle, outer core and inner core. The lithosphere is divided into plates; their movement forms mountains, volcanoes, earthquakes and ocean trenches at plate boundaries (divergent, convergent and transform) [7].

Landforms and processes. Weathering, erosion and deposition shape landscapes. Rivers produce valleys, floodplains and deltas; glaciers, waves and wind create other landforms [7].

Atmosphere and weather. Heat from the Sun drives winds and weather. Air pressure systems, fronts and the Coriolis effect shape circulation. Tropical cyclones form over warm oceans [7].

Climate. Controls of climate are latitude, altitude, distance from the sea, ocean currents and winds. The Köppen system classifies climates by temperature and rainfall: tropical, dry, temperate, continental and polar [7].

Monsoons are seasonal wind reversals that bring rain to much of South and Southeast Asia and strongly affect agriculture [7].

Hydrology and oceans. The water cycle includes evaporation, condensation, precipitation and runoff. Ocean currents move heat. A drainage basin collects water for a river system [7].

Biomes and soils. Rainforest, savanna, desert, temperate and boreal forests and tundra reflect climate. Soil forms from parent rock, climate, organisms, relief and time.

Natural hazards: earthquakes, volcanoes, tsunamis, floods, landslides, droughts and cyclones. Risk depends on hazard and vulnerability, and is reduced by preparedness and planning [7].

Climate change. Human activities have increased greenhouse gases and warmed the planet, raising sea level and altering rainfall patterns; mitigation and adaptation are responses [7].

Review: What type of plate boundary produces mid-ocean ridges? (Answer: a divergent boundary.)