Atmospheric Composition and Climate Factors
Atmospheric Composition
The Earth’s atmosphere is a wrapper composed of gases and other gaseous elements not in suspension. The main gases are Nitrogen (N), Oxygen (O2), Argon (Ar), and Carbon Dioxide (CO2). Atmospheric dust and living material are present in small quantities.
These gases originate from the Earth’s rocks and materials. Initially, the atmosphere contained large amounts of carbon dioxide and water vapor, with less oxygen. The oxygen production process began in the oceans due to early single-celled organisms. Photosynthesis released oxygen, which was initially poisonous to older life forms but eventually enabled animal and plant respiration and combustion.
Nitrogen is the most abundant gas and is very stable, maintaining atmospheric pressure levels.
Atmospheric Structure
- Troposphere: The layer nearest the ground where weather phenomena occur.
- Stratosphere: Contains the ozone layer, which protects against ultraviolet radiation.
- Ionosphere: Characterized by its wealth of ions, reflecting radio waves.
- Exosphere: Particles are very far apart.
Weather and Climate
Weather is a momentary atmospheric state, linked to a specific place and time. Climate is the set of atmospheric conditions characterizing a region over a long period.
Weather Elements
- Temperature: The amount of heat in the atmosphere.
- Atmospheric Pressure: The force exerted by the atmosphere.
- Winds: Movements of air masses due to pressure differences.
- Precipitation: Water falling by gravity.
- Humidity: The amount of water vapor in the air.
Humidity Concepts
- Saturation Point: The maximum moisture an air portion can hold without precipitation.
- Absolute Humidity: The amount of water vapor present at a given time and place.
- Relative Humidity: The ratio of water vapor present to the maximum possible amount.
Climate Factors
- Latitude: Uneven solar heating across different latitudes.
- Altitude: Distance measured vertically from sea level.
- Oceans and Land Masses: Water heats and cools slower than land.
- Winds: Contribute to climate diversity through air mass movement.
- Oceanic Currents: Transfer heat through water movement.
- Vegetation: Acts as a thermal moderator.
- Mountain Barriers: Affect air mass movement and temperature.