ATMOSPHERE

• Earth's atmosphere


  Helps the planet to be habitable, composed of multiple layers characterized by chemical composition, density, and temperature changes with height

  
• Troposphere


  • 0-10 km
  • Crucial for life on Earth, contains breathable air and supports weather patterns
  • Temperature decreases with ascent due to absorption of solar energy by the ground and heat transfer

  
• Stratosphere


  • 12-50 km
  • Contains higher concentration of ozone (O₃) molecules, which absorb harmful ultraviolet (UV) radiation from the Sun
  • Temperature increases due to absorption of UV radiation by ozone

  
• Mesosphere


  • 50-80 km
  • Plays a role in meteor showers and the decay of space debris
  • Coldest layer, temperatures decrease with altitude
  • Where auroras (such as the Northern Lights) occur due to interactions with charged particles

  
• Thermosphere


  • 80-700 km
  • Experiences high temperatures due to intense solar radiation
  • Gas molecules become ionized by solar energy, creating the ionosphere that facilitates radio communication
• Exosphere


  • 700-10000 km
  • Marks the transition from Earth's atmosphere to outer space, gateway to space exploration
  • Satellites and spacecraft orbit in this region

  
• Ionosphere


  • 48-965 km above sea level
  • Ionized by solar radiation, high-energy solar photons collide with atmospheric gases and knock electrons loose, creating charged particles (ions)
  • Consists of D Layer, E Layer, and F Layer which reflect different radio frequencies
• The aurora is called Aurora Borealis or northern lights in the northern hemisphere, and Aurora Australis or Southern Lights in the southern hemisphere

  
• Clouds can help to "clean" the atmosphere by taking up pollutants from the air and raining them out
• Clouds


  Captivating formations in the sky, their creation involves an interplay of water vapor, temperature, and tiny particles

  
• Cloud formation


  1. Air volume becomes saturated with water vapor

  2. Cooling or pressure drop causes excess water vapor to change into a liquid or solid
• Aerosols


  • Tiny particles floating in the air, such as dust, salt crystals, bacteria, or even volcanic ash, provide surfaces for water vapor to condense
• Sunlight hits the atmosphere


  It scatters due to particles like dust, smoke, and other airborne substances, creating glorious red and orange sunsets
• Fog


  A cloud that forms near ground level, reducing horizontal visibility to less than 1,000 meters (3,281 feet)
• Certain soluble gases, like sulfur dioxide, can aid droplet growth by forming dilute sulfuric acid, so fog can occur in both clean and polluted environments
• Steam Fogs


  • Produced when cold Arctic air moves over ocean currents, inlets, or coastal areas
• Arctic Sea Smoke


  • Cold Arctic air moves over warmer water surfaces, as the air becomes saturated, fog rises like steam or smoke