Download Clouds Types

Clouds Types
(pg 106)
 Are made of tiny droplets of water
 The way they are formed depends on
conditions of the wind, temperature and
humidity.
 The variation in these conditions results in
the many different types of clouds you see
in the sky.
 Puffy clouds with
flat bases.
 Formed by
convection currents
or by air masses
meeting.
 Form in endless layers
 You cannot see shapes or forms in these clouds
because they are flat
 Form when air masses meet or when a layer of
air is moved up the side of a
mountain range
 Can also form by conduction
 Made from ice
crystals that form
when the dew point
temperature is very
low
 Water vapour
changes directly
from a gas to a solid
Cumulonimbus
 Sometimes cumulus
clouds carry
precipitation. They
are known as
cumulonimbus
clouds. These clouds
can bring about huge
thunder storms as
well. Nimbus
means “to carry
precipitation ”.
Stratus
 Stratus means to
“stretch out”.
There is another
type of cloud
named
nimbostratus.
These clouds also
bring about days
that are grey and
rainy/snowy.
 Stratus clouds
 Nimbostratus
clouds: clouds that
bring rain
 Stratocumulus
clouds: lumpy low
lying clouds that
form in layers
 Altostratus clouds: display a uniform grey
appearance and darken the sky
 Altocumulus clouds: display a patchy cotton ball
appearance
 Cirrus Clouds
 Cirrostratus clouds: take the form of individual
puffs and form in patchy groups
 Cirrocumulus clouds: a more continuous
appearance than other high clouds and they
blanket the sky
 Cumulus Clouds
 Cumulonimbus
clouds: large puffy
dark clouds that
carry rain or snow
 Complete practice sheet (cloud drawings and
labelling)
 Video (5:05)– Weather 101 – A tutorial on cloud
types
Precipitation
(pg 107)
Types of Precipitation
 Can be defined as the result or product of
the condensation of atmospheric water
vapour which falls to or is deposited on
the surface of the Earth.
 When water droplets
in a cloud combine
or grow to a
diameter between
0.5 mm and 2 mm they will then fall to the
ground as rain.
 Most rain begins as crystals that stick
together and melt as they fall through the
warmer air.
 The crystals in
clouds stick together
and form larger
flakes.
 If the air is cold the
snowflakes will fall
to the ground
 Snow flurries show up
quickly and often take
people by surprise.
Flurries are a brief
burst of snow that can
be an indication that
something more
serious is on the way.
 Sleet is formed when
snowflakes meet warm
air and turn into rain
but then meet colder air
closer to the ground and
freeze again.
 When they freeze again
they do not form crystals
they form ice pellets
called sleet
 This forms when the air
is warm enough to
allow rain to fall but
the ground and objects
below are below the
freezing point.
 When the rain hits the
ground or objects near
the ground, it will
freeze instantly.
 Freezing drizzle is very similar to freezing rain
in that the drizzle freezes instantly once it hits
the cold ground.
 The difference is that the droplets are much
smaller than the rain drops in freezing rain
 Hail begins as frozen
raindrops known as
hailstones. Instead of
falling directly to the
ground they are carried by
the wind into large
cumulonimbus clouds.
 If the temperature inside the
cloud is at or below freezing
they combine with droplets
that coat and freeze on the
hailstones which fall to the
ground
 Practice sheet – Fill in the blanks (ppt)
 Video – What is Precipitation?
 Practice sheet: Rain or Shine Quiz
 Continue with review questions (chapter 1.1 – p. 25:
#1, 2, 4, 5, 6, 7, 8, 11, 13, 14