Earth’s Atmosphere: Layers, Phenomena, and Pollution

Posted on Feb 3, 2025 in Geology

Earth’s Atmosphere: Layers and Composition

Troposphere

The troposphere is the layer that is in contact with the soil. Here, the temperature drops to -55ºC. This layer contains approximately 90% of the atmosphere’s upper interface.

Stratosphere

The stratosphere has a thickness of 30 km. At the top, ultraviolet rays of the sun collide with oxygen molecules (O2). The reaction releases heat, so the top is about -17ºC. In addition, the stratosphere is a region rich in ozone, the ozonosphere.

Mesosphere

The mesosphere has a thickness of some 40 km. The temperature drops to less than -100ºC in the mesopause.

Ionosphere

The ionosphere is the external layer. Solar radiation heats the top. The top is called the exosphere. At 500 km altitude, there is nothing because of the air in the vacuum of space. Shooting stars and the polar auroras are produced here.

Cloud Types and Formations

  • Cumulus: Dense clouds with a cotton-like appearance. The top is shiny, and the bottom is usually dark.
  • Nimbostratus: Grayish, diffuse-looking cloud layers formed due to precipitation.
  • Cirrus: High, white clouds with fibrous bands that can appear as separate elements.
  • Altostratus: Flat clouds in the form of long, parallel bands that cover much of the sky.

The Phenomenon of Horizontal Rain

In the Canary Islands, rainfall is scarce, but the moist winds from the northeast Atlantic Ocean, called trade winds, hit the mountains, cool, and lose much moisture. There is also a permanent haze, and sometimes, a real sea of clouds.

The moisture does not usually cause rain but constantly moistens these plants, dripping water. This phenomenon is called “horizontal rain” and is the reason why a rainforest, called laurel forest, develops in some areas of the Canary Islands.

Air Pollution: Causes and Implications

Carbon Dioxide (CO2)

Carbon dioxide is produced by burning fossil fuels. Its accumulation in the atmosphere causes an increase in the greenhouse effect and gradual warming, leading to climate change.

Implications:

  • Increase in destructive tropical cyclones
  • Melting of polar ice caps
  • Rising sea levels
  • Changes in rainfall patterns
  • Severe droughts in several parts of the world

Sulfur Oxides and Nitrogen Oxides

These are produced from the combustion of coal and poor-quality gasoline. When these oxides combine, they form acid rain and snow. This phenomenon is called “acid rain”.

Implications:

  • Deterioration of buildings and monuments
  • Death of plants and animals

CFC Gases (Chlorofluorocarbons)

These are gases that are used in sprays and almost everything that carries gas. They cause the reduction of the ozone layer.

Implications:

  • Serious diseases
  • Burns

Soot

Soot consists of very tiny solid particles, which form the remainder of the combustion of coal and other fuels.

Implications:

  • Increased waste in cities
  • Deterioration of buildings and monuments