Grade 4 Science
Wk – 11 28/7
How is The Water Cycle related to
weather?
Kinds of precipitation
Sometimes we think of precipitation as bad weather. But all the
kinds of precipitation are simply part of the water cycle.
What causes different kinds of precipitation? Most water on
Earth, such as ocean water, is liquid.
Rain, the most common kind of precipitation, is
liquid water. Rain falls if the temperature is higher
than 0˚C.
Sleet is frozen rain. Sleet is caused when rain
falls through a layer of freezing cold air. This
turns the rain into ice pellets.
Snow is made of ice crystals. Snow is caused when
the air temperature is so cold that water vapor
turns into ice.
Hail is round pieces of ice. Hail is caused
when rain freezes and then falls to a
warmer part of the air. Raindrops coat
the frozen rain before it is carried back
up to a colder part of the air by wind. The
new liquid coating freezes too. This
happens over and over until the hail is too
heavy and it falls to the ground.
What causes rain to become sleet?
__________________________________________________
Draw the 4 types of precipitation and give a description of them
Rain: Rain is liquid water. It falls
when the temperature is higher
than 0˚C
Severe Storms
Heat from the sun powers the water cycle. This same energy
causes severe storms.
One type of severe storm is a thunderstorm.
Thunderstorms are storms with lightning,
strong winds and heavy rain.
Sometimes tornadoes form. A tornado is a fast
spinning spiral of wind that stretches from the clouds
of a thunderstorm to the ground.
Another type of severe storm is a hurricane. Hurricanes are large
tropical storms. Hurricanes form over warm water in the tropical oceans. These storms can
last for weeks at sea. But when it reaches land, it no longer gets energy from the water and it
becomes weaker. The center of the storm is called the “eye”. The “eye” of the storm is calm.
Watch 'The Magic School Bus'
about weather
OR
Look at videos on internet.
Weather safety
Severe storms are dangerous. Injuries can be caused by things
flying around. Floods can happen.
It is important to keep yourself safe during severe weather. One
way to stay safe is to follow the safety rules in your town. Listen to
the radio and watch TV to know about storms in your area. Stay
inside unless you are told to leave.
Sometimes people are asked to
leave an area before a storm
strikes.
Compare and contrast
How is a tornado different from a hurricane?
My Dictionary
precipitation: ________________________________
rain: ______________________________________
hail: ______________________________________
sleet: _____________________________________
snow: _____________________________________
thunderstorms: ______________________________
hurricanes: _________________________________
tornadoes: __________________________________
Homework
Find the answer to the following question.
Do hurricanes have names? Explain your answer.