1. THE EARTH ATMOSPHERE

2. THE EARTH ATMOSPHERE
Atmosphere is the protective layer of gas that surrounds the planet.
LIMITS OF THE ATMOSPHERE
It begins in the planet´s surface.
The upper limit is at km.
The atmospheric gases dissappear with the altitude.
At the highest level the composition is similar to space.

3. Air, dust, pollen, microorganisms
COMPOSITION
Air, dust, pollen, microorganisms
Earth is the only planet with enough oxygen to support life.
Variable water because of the atmospheric humidity.
The composition depends of the altitude.
Up to 80 km  homogenous and contains N and O.
From 80 km  fewer gases (varied composition)
EARTH´S EARLY ATMOSPHERE
It began to form from volcanic gases.
It was formed of carbon dioxide with lower oxigen.
Cicle Change:
Oxigen entered from photosynthesis
Water vapour condensed created seas and oceans.
Carbon dioxide dissolved into water (absorbed by living things)

4. THE ATMOSPHERE´S STRUCTURE
It is structured in layers.
Each layers has a different gas composition and different temperature conditions.
The densest gas is found in lower levels.
In the highest level there is nearly no gas.
“Strange light formations (Northern Lights) appear at night in the atmosphere in the Northern Hemisphere”

5. EXOSPHERE Highest limit
EXOSPHERE Highest limit. Molecules of helium and hydrogen T: daytime (thousand of ºC) and night (-273ºC) THERMOSPHERE Temperature: 1500ºC Solar radiation produces electrically charged ionised gases. MESOSPHERE T: decrease as altitude increases. -100ºC STRATOSPHERE Ozone layer. Absorbs ultraviolet radiation. High temperature. TROPOSPHERE Water vapour and 80% of gases. It is in contact with surface. Meteorological phenomena occur here (wind, rain, cloud formation). T. increases 0,65ºC for every 100m of altitude.

6. SOME DIFFERENT LINKS https://www.youtube.com/watch?v=5sg9sCOXFIk