Layers of Earth’s Atmosphere: Troposphere,Stratosphere

Layers of The Earth

Layers pf the Earth is 4 types they are namely:

  1. Troposphere
  2. Stratosphere
  3. Mesosphere
  4. Thermosphere

Layers of the Earth atmosphere

1. Troposphere

Troposphere is the lowest layer of our atmosphere. Starting at ground level, it extends upward to about 10 km above sea level. Humans live in the troposphere, and nearly all weather occurs in this lowest layer. Most clouds appear here, mainly because about 75% of all of the air in the atmosphere, and almost all of the water vapor. The decrease in temperature with height is a result of the decreasing pressure. If a parcel of air moves upwards it expands (because of the lower pressure). When air expands it cools. So air higher up is cooler than air lower down.

The top of the troposphere is called the Tropopause. This is lowest at the poles, where it is about 7 – 10 km above the Earth’s surface. It is highest (about 17 – 18 km) near the equator.

2. Stratosphere

The layer above the Troposphere is known as the Stratosphere. Gases in the stratosphere are layered the air is very thin little moisture as well, and is extremely cold lower stratosphere. Although the lower part of the stratosphere is cold, the heat in the stratosphere increases as altitude increases. This is because of the ozone layer in the upper part of the Stratosphere. The Ozone layer absorbs ultraviolet radiation from the sun, and as a result, warms up the air. This ozone layer is key to our safe living on Earth.

3. Mesosphere

Above the stratosphere is the Mesosphere. It extends upward to a height of about 85 km (53 miles) above our planet. Most meteors burn up in the mesosphere. Unlike the stratosphere, temperatures once again grow colder as you rise up through the mesosphere. The coldest temperatures in Earth’s atmosphere, about -90° C (-130° F), are found near the top of this layer. The air in the mesosphere is far too thin to breathe; air pressure at the bottom of the layer is well below 1% of the pressure at sea level, and continues dropping as you go higher.

4. Thermosphere

The uppermost atmosphere is called the Thermosphere. Here, the temperature again increases with altitude. This is because atoms of nitrogen and oxygen absorb high-energy solar radiation and give off thermal energy… this causes the temperature to increase up to 1,000 degrees Celsius. Thus, the thermosphere has particles moving very fast. Heat is the transfer of thermal energy between objects of different temperatures. Therefore, particles must touch one and another to transfer heat. In the Thermosphere, it is has a low density, Thus the particles in the Thermosphere usually don’t collide, thus not giving off heat.