Observe the picture
?
What does this picture depict/show?
•?
Humidity and Rainfall
Geography
What is Humidity?
• Discuss 3 terms
• Evaporation
• Condensation-Forms of condensation.
• Fog and mist
Evaporation
Forms of Condensation
Fog and mist –when moist air in winter comes in contact with cold surface of the earth, then the process of condensation takes place and a cloud
is formed at ground level. A thick cloud is called fog and a thin cloud is called mist. Visibility reduces during fog.
Cloud – Clouds are formed in a similar manner as fog and mist but they are formed at a higher altitude. We see four types of clouds – cumulus,
stratus, cirrus and nimbus (which are rain- bearing cloud).
Dew– Dew forms during cold winter nights when moist air comes in contact with cold surfaces like plants, metal objects, grass etc. The moisture
turns into water and is seen as tiny dew drops.
Frost – In winters when the nights are extremely cold i.e. the temperature drops to below freezing point, the dew drops freeze to form tiny ice
crystals or a thin sheet of ice on cold surfaces mentioned above. This is harmful to the standing crops.
Fog
Clouds
Activity
• How clouds are formed when warm air gets cooled.
• Large glass jar
• A small tray
• Some ice cubes and hot water.
Dew
Frost
Precipitation
Rainfall
Rainfall
Changing of water into water vapour because of heating
Process of changing of water vapour into water in the air
Condensation
Forms of condensation
aFog
bMist
C. Clouds
d. Dew
e. Frost
Precipitation
Process in which condensed
water vapour falls down on
the earth
a.Rain
b.Snow
c. Sleet
d. Hail
.
Sleet are small ice particles that form from the freezing of liquid water drops, such as raindrops. ...
Sleet is also called ice pellets. Hail is frozen precipitation that can grow to very large sizes through
the collection of water that freezes onto the hailstone's surface.