This document defines key terms related to the atmosphere and its structure. It describes the five main layers of the atmosphere from lowest to highest - the troposphere, stratosphere, mesosphere, thermosphere, and exosphere. The troposphere contains 70% of the atmosphere's mass and is where weather occurs. The stratosphere contains the ozone layer. The mesosphere reflects sound waves. Above that, the thermosphere and exosphere experience increasing temperatures with altitude. Transition zones between layers like the tropopause and stratopause are also outlined.

2. Terms
• Atmosphere-The gases, droplets, and particles
surrounding Earth’s surface.
• Weather-Day to Day conditions of the
atmosphere.
• Climate-The statistical properties of the
atmosphere, including measures of average
conditions, variability, etc.
• Climatology-The study of long term
atmospheric conditions.

3. FACT
-The total mass of the atmosphere is equivelant
to 5.65 billion million tons.

4. Levels of atmosphere
• Troposphere
• Stratosphere
• Mesosphere
• Thermosphere
• Exosphere

5. Vertical Structure
• Troposphere-
• Lowest layer of the atmosphere. Where
almost all weather and organisms take place.
Decreasing temperatures. Depth= 8 to
16km(3.6 to 10 miles).
• It contains 70% of all mass of atmosphere.
The density of troposphere is decreases with
altitude. This decreases of temperature with
altitude is known as Lapse rate.

6. Vertical Structure CONT.
• Stratosphere-
• Second lowest layer of atmosphere. It extend
about 50-55 km above the surface of the
earth.
• Ozone layer is found at around 20 km from
ground is called Ozonosphere and act as a
protective layer against harmful ultraviolet
radiations.
• Temperature increases with altitude.(positive
lapse rate)

7. Vertical Structure CONT.
• Mesosphere-
• Third layer in the atmosphere. Decreasing
temperature with altitude(negative lapse
rate). Depth=Approx. 80km(50 miles).
• This layer is very special as all sound waves as
well as short radio waves coming from earth
re reflected from this layer.

8. Vertical Structure CONT.
• Thermosphere-
• The upper layer from mesosphere in
atmosphere. Increasing temperature with
altitude. Depth=Begins at 80km to 500km.
• Ionisation of elements like oxygen and nitric
oxide take place in the upper most portion of
sphere is called the Ionosphere.

9. Vertical Structure CONT.
• Exosphere-
• The upper most layer of the atmosphere is
known as exosphere. It extend up to a height
of 1600km from the surface of earth.
• The temperature of this layer is more than
1200 °C is Found.

10. ADDITIONS
• Tropopause-
• The tropopause is the boundary in the Earth's
atmosphere between troposphere and
stratosphere. Transition zone where the
temperature ceases to decrease.
• Stratopause-
• Top of stratosphere, the temperature increases
with altitude, and the stratopause is the region
where a maximum in the temperature occurs.

11. ADDITIONS CONT.
• Mesopause-
• The mesopause is the boundary between
the mesosphere and the thermosphere. Due
to the lack of solar heating and very
strong radioactive cooling from carbon
dioxide, the mesosphere is the coldest region
on Earth with temperatures as low as -100 °C.

12. http://burro.cwru.edu/Academics/Astr201/Atmosphere/structure.jpg

13. Relevant Terms
• Homosphere-
• The lowest 80km of the atmosphere, which
the relative abundance of the permanent
gases is constant.
• Heterosphere-
• The high atmosphere where gases are not well
mixed but rather are stratified according to
weight. Where lighter weighing gases are
found.

14. The End