Why does it rain? (think back to work on the water cycle.)
Write a brief description of how it rains, use the words to
help you (but they’re not in order!!)
Condenses
cools
vapour
clouds
precipitation
Rises
heats
There are 3 ways rain or precipitation is produced…
Convectional Rain
Convectional
rainfall
This form of rain is common
in the east of England
during the summer.
1. The sun heats the ground and warm air rises.
2. As the air rises it cools and water vapour condenses to
form water droplets.
3. Water droplets join together to form clouds.
4. Heavy rain storms occur.
Relief rain
Relief rainfall
Relief rain is formed when
air is forced to cool as it
rises over relief (height)
features in the landscape
(hills or mountains).
1. Air is forced to rise and cools by 1°C per 100m.
2. As the water vapour in the air condenses, it forms clouds
and rains.
3. The air starts to descend and begins to warm up again.
4. As air warms up, it can hold more water vapour - clouds
disappear and rain stops. This side is known as a
RAINSHADOW.
Frontal rain
Frontal Rainfall
1. An area of warm air meets and area of cold air.
2. The warm air is forced over the cold air
3. Where the air meets the warm air is cooled and water
vapour condenses.
4. Clouds form and precipitation occurs.
Make a copy of all three types of
rainfall, and explain what happens at
stage 1, 2, 3 and 4 for each of them.
Copy and complete:
I know how it rains. Firstly warm _____ rises because hot
air is lighter than cold air. As it rises it ________. This
makes condensation. We see this in the sky as ________.
When the clouds get to a certain point they can hold no
more _________. This is when it ______.
Relief Rainfall.
Relief rainfall happens when the air is forced to ______ as it
hits the mountain. As it rises it_______, forms clouds and
then it _______.
WATER RAIN COOLS CLOUDS
COOLS RAINS AIR
RISE
Cloud cover is measured in Oktas. Today there are _______
Oktas of cloud.
We know there are many different types of cloud, because
not all cloud looks the same.
You might see more
than one of these
types of clouds in the
sky all at once.
These are the main types of cloud:
Cirrus clouds are wispy, like a lock of
hair, and are high up.
Stratus clouds are layers, and are
middle to low clouds.
Cumulus means ‘heap,’ cumulus clouds
look a bit like cotton wool balls
Cumulonimbus clouds are tall and dense,
usually resulting in rain or storms.
Any cloud with the word cirro or cirrus is a high cloud.
Any cloud with the word alto in it is about in the middle.
Any cloud with nimbo or nimbus added onto it means it is
producing precipitation.
Add labels to your diagram of the clouds.
Type of Cloud
Appearance
Altitude (height)
Cumulo-nimbus
=Thunderheads
Can cause lightning, thunder, hail, strong
rains, strong winds, and tornadoes
Near ground up to 75,000 feet
(Vertical clouds)
Cirro-stratus
Thin, wispy, appears in sheets. Located
above thunderheads
Above 18,000 feet
(High-altitude clouds)
Cirrus
Thin, wispy, filamentous, or curly
Above 18,000 feet
(High-altitude clouds)
Cirro-cumulus
Small, puffy, patchy and/or with a wavelike
appearance
Above 18,000 feet
(High-altitude clouds)
Alto-cumulus
Medium-sized puffy, patchy, scattered
clouds - often in linear bands
6,500 - 20,000 feet
(Middle-altitude clouds)
Alto-stratus
Thin, uniform
6,500 - 20,000 feet
(Middle-Alttude clouds)
Strato-cumulus
Broad and flat on the bottom, puffy on top,
Below 6,500 feet
(Low-altitude clouds)
Cumulus
Puffy and piled up.
Below 6,500 feet
(Vertical clouds)
Stratus
Uniform, flat, thick to thin layered clouds
will ill-defined edges
Below 6,500 feet
(Low-altitude clouds)
Nimbo-stratus
Uniform, dark, flat, low, featureless clouds
that produce precipitation
Below 6,500 feet
(Low-altitude clouds)
alto-cumulus - Middle-level, medium-sized puffy clouds.
alto-stratus - Middle-level, layered clouds.
cirro-cumulus - High-altitude, small, wispy, patchy, puffy
clouds.
cirro-stratus - High-altitude, thin, wispy clouds in layers.
cirrus - High-altitude, thin, wispy clouds.
cumulo-nimbus- Large, dense, towering clouds that cause
thunderstorms.
cumulus - Low, puffy clouds.
fog - Ground-hugging clouds.
nimbo-stratus - Low, dark, rain cloud.
stratus - Low, layered, horizontal, wispy clouds with a flat
base.
strato-cumulus - Low clouds, broad and flat on the bottom,
puffy on top (higher than cumulus and lower than altocumulus
Now answer the following questions:
1.What
2.What
3.What
4.What
5.What
are clouds?
is cloud cover measured in?
are the three main cloud types?
name do high level clouds begin with?
types of clouds does convectional rainfall cause?
Cumulus
Cumulonimbus
Cumulonimbus
Cumulus
Cirrus
Stratus
Cumulus
Stratus
Cirrus
Cumulus
Cirrus
Stratus
Cumulonimbus
Cumulus
Cirrus