Earth's Structure and Atmosphere

Study Notes

Crust: Outermost solid layer, 5-70 km thick, composed of rocks and minerals
Mantle: Thick layer beneath the crust, 2,900 km thick, hot and viscous rock
Outer Core: Liquid iron and nickel, 2,250 km thick, responsible for generating magnetic field
Inner Core: Solid iron and nickel, 1,220 km thick, hottest part of the Earth (5,000-6,000°C)

Composition: 78% nitrogen, 21% oxygen, 1% other gases
Layers:
1. Troposphere: lowest layer, up to 12 km, where weather occurs
2. Stratosphere: 12-50 km, contains ozone layer
3. Mesosphere: 50-80 km, coldest layer (-90°C)
4. Thermosphere: 80-600 km, hot layer, interacts with solar wind
5. Exosphere: outermost layer, where atmosphere interacts with space

Continents: 7 large landmasses, including Africa, Antarctica, Asia, Australia, Europe, North America, and South America
Mountains: ranges of mountains, including the Himalayas, Andes, and Rocky Mountains
Volcanoes: landforms that erupt with magma and gas
Deserts: dry regions, including the Sahara, Mojave, and Gobi deserts

Plate Tectonics: movement of Earth's crust, resulting in earthquakes, volcanoes, and mountain formation
Weathering: breakdown of rocks into sediment, through wind, water, and ice
Erosion: removal of sediment, through wind, water, and ice
Geological Time Scale: 4.5 billion year history of Earth's formation and development

Earth's crust is the outermost solid layer, ranging in thickness from 5-70 km, composed of rocks and minerals.
The mantle is a thick layer beneath the crust, measuring 2,900 km in thickness, and is characterized by hot and viscous rock.
The outer core is a liquid layer of iron and nickel, 2,250 km thick, responsible for generating the Earth's magnetic field.
The inner core is a solid layer of iron and nickel, 1,220 km thick, and is the hottest part of the Earth, with temperatures ranging from 5,000-6,000°C.

The atmosphere is composed of 78% nitrogen, 21% oxygen, and 1% other gases.
The troposphere is the lowest layer of the atmosphere, extending up to 12 km, and is where weather occurs.
The stratosphere is the layer above the troposphere, spanning 12-50 km, and contains the ozone layer.
The mesosphere is the coldest layer of the atmosphere, ranging from 50-80 km, with temperatures reaching -90°C.
The thermosphere is a hot layer of the atmosphere, extending from 80-600 km, and interacts with the solar wind.
The exosphere is the outermost layer of the atmosphere, where it interacts with space.

Oceans cover 71% of the Earth's surface and have a total volume of 1.3 billion km³.
Freshwater makes up only 2.5% of the Earth's water, with most of it being frozen in glaciers and ice caps.
The water cycle is the process of evaporation, condensation, and precipitation.

There are 7 large continents, including Africa, Antarctica, Asia, Australia, Europe, North America, and South America.
Mountain ranges include the Himalayas, Andes, and Rocky Mountains.
Volcanoes are landforms that erupt with magma and gas.
Deserts are dry regions, including the Sahara, Mojave, and Gobi deserts.

Plate tectonics is the movement of the Earth's crust, resulting in earthquakes, volcanoes, and mountain formation.
Weathering is the breakdown of rocks into sediment, through wind, water, and ice.
Erosion is the removal of sediment, through wind, water, and ice.
The geological time scale is a 4.5 billion year history of the Earth's formation and development.