Download The Hydrosphere

The Hydrosphere
The Hydrosphere
• The hydrosphere is all of the Earth’s water –
both fresh and salt. Water covers about 70% of
the surface of the Earth.
• Of this water on Earth – most of it (97.5%) is
found as salt water. That means that only 2.5%
of the Earth’s water is fresh water – the stuff we
need to drink.
• Of all the fresh water on Earth, 87.3% of it is
contained in the polar ice caps and glaciers.
Less than 1% of the Earth’s fresh water comes
from lakes and surface sources.
The Water Cycle
• Water has an effect on the weather in all of
its forms – solid, liquid and gas.
• Water on Earth ends up in the atmosphere
(as vapour) due to the heat energy of the
sun. This can occur through…
– Sublimation – Solid water into vapour.
– Evaporation – Liquid water into vapour.
– Transpiration – Water loss from plants.
The Water Cycle
• We need to get the water in the
atmosphere back to Earth to complete the
cycle.
• The water in the atmosphere condenses
and falls as precipitation from the clouds.
Precipitation may be rain, snow, hail, etc.
• The water continues to alternate between
the ground and the atmosphere.
The Water Cycle
Clouds & Fog
How Do Clouds Form?
• Clouds are formed in three ways – all of
which have warm air with a lot of moisture
in it meeting up with a drop in temperature.
• There are three cloud types
– Convective Clouds
– Frontal Clouds
– Orographic Clouds
Types of Clouds
• Convective Clouds – Moisture-filled air goes
over very warm ground and rises up into
atmosphere. Clouds form as moisture cools and
condenses.
• Frontal Clouds – A warm air front meets and
collides with a cold air front. The warm air is
pushed up over the cold air where it cools and
condenses and forms clouds.
• Orographic Clouds – Warm air with moisture is
pushed up a mountain by the wind. The warm air
rises, cools, condenses and clouds form.
Convective Clouds
Convective Cloud Formation
Frontal Clouds
Frontal Cloud Formation
Orographic Clouds
Orographic Clouds
What the Fog?
• Fog is actually a cloud that forms near the
ground. Moisture-filled air blows over very
cold ground (night or snow-covered
usually). The moisture cools, condenses
and forms clouds just above the ground –
fog!
FOG!
FIN