ATMOSPHERE

Definitions of Earth's Subsystems

  • Lithosphere: Solid earth, including rocks and soil.

  • Atmosphere: Layer of gases surrounding Earth, retained by its gravity.

  • Hydrosphere: All water on Earth, including oceans, rivers, and lakes.

  • Biosphere: All life forms on Earth.

Composition of Atmosphere

  • Major Components:

    • Nitrogen (78%): Most abundant; relatively inert; dilutes oxygen to reduce combustion rates.

    • Oxygen (20.95%): Vital for respiration and combustion.

    • Argon (0.93%): Noble gas used in light bulbs and welding.

    • Carbon Dioxide (0.038%): Used in photosynthesis; warms the atmosphere.

    • Trace Gases: Ne, He, CH4 (methane), O3 (ozone), and variable components like water vapor.

Characteristics of the Atmosphere

  • Altitude Effects:

    • 120 km: Noticeable atmospheric effects begin.

    • Karman Line (100 km): Boundary between atmosphere and outer space.

  • Insulating Properties:

    • Retains heat, blocking UV radiation from the sun.

    • Measured by satellites (e.g., TERRA, MOPITT, MAPS).

Detailed Gases in the Atmosphere

  • Nitrogen:

    • Abundant, used in fertilizers and refrigeration.

    • Essential for plants and animals.

  • Oxygen:

    • Essential for aerobic life and combustion.

    • Used in various industries including steelmaking.

  • Carbon Dioxide:

    • Critical for photosynthesis in plants.

    • Significant in warming the atmosphere and used in beverage production.

  • Argon:

    • Abundant noble gas, used in light bulbs and as an inert gas in welding.

  • Neon:

    • Employed in lights and advertisements.

  • Helium:

    • Used in balloons and medical applications (MRI).

  • Methane:

    • Produced from organic matter degradation; contributes to greenhouse gas effects.

  • Ozone (O3):

    • Absorbs harmful solar radiation; vital in the stratosphere.

    • Measurements in Dobson Units (DU).

  • Water Vapor:

    • Most important greenhouse gas, fundamental for cloud formation and climate regulation.

Structure of the Atmosphere

  • Layers:

    • Troposphere: Lowest layer; weather and climate occur; extends up to 12 km; temperature decreases with altitude.

    • Stratosphere: Contains ozone layer; temperature increases with altitude; extends from 12 km to 51 km.

    • Mesosphere: Coldest layer; extends from 50 km to 80 km; protects Earth from meteoroids.

    • Thermosphere: Warmest layer; extends from 80 km upwards; varies with solar activity.

    • Ionosphere: Contains ions; essential for radio wave transmission.

    • Exosphere: Outermost layer; consists of light gases like hydrogen and helium.

Weather

  • Definition: The state of the atmosphere at a specific time and location.

  • Influenced by various factors including temperature and pressure.

Factors Affecting Weather

  • Temperature:

    • Measured using thermometers; influences humidity and weather conditions.

    • Cold/warm air interactions lead to phenomena like thunderstorms.

  • Humidity:

    • Amount of water vapor in the air; warmer air holds more moisture.

  • Clouds:

    • Formed from water droplets or ice crystals; regulate temperature and precipitation.

    • Types:

    • Cumulus: Fluffy, white clouds.

    • Stratus: Layered clouds covering the sky.

    • Cirrus: Thin, wispy high-altitude clouds.

  • Wind:

    • Air movement caused by pressure differences; essential for weather dynamics.

    • Can lead to storm formation and temperature changes.

  • Precipitation:

    • Any water particles falling from the atmosphere; types include rain, snow, sleet, hail, etc.

Climate

  • Definition: The long-term pattern of weather conditions in a certain area.

Köppen Climate Classification**

  • Types:

    • Tropical: High temperatures year-round.

    • Dry: Regions where evaporation exceeds precipitation.

    • Temperate: Moderate seasonal climates.

    • Continental: Severe winters and warm summers.

    • Polar: Characterized by cold temperatures.

  • Distribution: Varies globally, depicted in a chart format demonstrating percentage allocations for each climate type.