water and air on earth
TRANSCRIPT
Water and air on Earth
ALL LIVING THINGSNEED
WATER
ANIMALS PLANTS
PEOPLE
WHAT’S WATER LIKE?
NO COLOUR NO SMELL
NO TASTE
All living things need water and air to live.
• It is found in three STATES
Water changes state when you heat it or cool it.
SOLID LIQUID GAS
The three forms of water• You can find water in 3 different forms:– Liquid– Solid– Gas
Water is a liquid. Ice is a solid at 0 degrees.
Water vapour is a gas at
a hundred degrees
DOES WATER CHANGE?
• Water turns to GAS when it is HOT.
• Water turns to SOLID when it is VERY COLD.
• Water turns to liquid at ROOM TEMPERATURE.
DOES WATER CHANGE?
It freezes
It melts It evaporates
It condenses
Water
• We need water for drinking.• We need water for swimming.• We need water for cooking.• We need water for cleaning.• We need water for washing.• We need water for watering the plants.
USES OF WATER
SWIMMING WASHING
WATERING THE PLANTS
DRINKING COOKING
CLEANING
USES OF WATER
WATER AND LAND• The Earth is covered with WATER and LAND.• There is more water than land on the Earth!• We can find water is many different places. Most of
the water is salty.
Where we find water• We can find water in –A lake.–A river.– In a waterfall.– The clouds.– The seas.–Groundwater.–Reservoirs.– The icecaps.
Where we find water
We find water in a lake.
We find water in a waterfall.
We find water in a river.
We find water in the clouds.
We find water in the icecaps.We find water in the sea.
We find water in reservoirs.We find groundwater.
FRESHWATER• Most of the water on Earth is –Saltwater.
• Only a little is –Freshwater.
FRESHWATER SALTWATER
Oceans and seas are saltwater.
Rivers, lakes, icecaps, groundwater and reservoirs are freshwater.
WATER HERE IS GAS.
WATER HERE IS LIQUID.
WATER HERE IS SOLID.
ALL ABOUT AIR
• Air is a mixture of gases.
• We cannot see air but it is all around us.
• People and animals breathe oxygen from the air.
• All living things need air to live.
• Plants can’t grow without air.
• People and animals can’t breathe without air.
Atmosphere is the layer of gases that sorround the Earth
AIR IS FOUND IN THE ATMOSPHERE.
Characteristics of air
• Air is a mixture of gases, but it consists mainly of OXYGEN and NITROGEN.
• As water it has NO SMELL, NO TASTE, AND NO COLOUR
OXYGEN
NITROGEN
WIND
• Wind is moving air.• Hot air goes up• Cold air goes down.• The difference in temperature causes wind.• Wind moves air from one place to another.• This is why clouds move.
Tipes of wind• No wind• Little wind• Strong wind• Very strong wind
• Calm• Breeze• Gale• Hurricane
An anemometer measures how fast the wind is moving.
A weather vane tells us wind direction
Weather• Weather is the state of the atmosphere at a
certain time in certain places.
The weather can be windy. The weather can be
sunny.
The weather can be cloudy.
The weather can be rainy.
The weather can be stormy.
The weather can be snowy.
The weather can be foggy.
Temperatures and Precipitation
• When the weather is HOT, the temperature is HIGH.
• When the weather is COLD, the temperature is LOW.
PRECIPITATION• Precipitation is water falling from the
atmosphere to the ground. • It can be:• LIQUID ---------RAIN DROPS• SOLID -------------- SNOW FLAKES• BALLS OF ICE --------- HAIL STONES
Measuring weather
• ANEMOMETER: WIND SPEED
• RAIN GAUGE: RAIN FALL
• TEMPERATURE: THERMOMETER.
FRESHWATER• We can only drink CLEAN freshwater. We call
this DRINKING WATER.
• Water from rivers and lakes is NON-DRINKING WATER.
DON’T WASTE WATER• We must save water. • Only the 3% of all the water on Earth is
freshwater.
The drought
• When it doesn´t rain for a long time it’s difficult for the plants and fish to survive.
• They usually happen in summer.
What is the water cycle?• The water cycle is a continuous process of
EVAPORATION, CONDENSATION, PRECIPITATION and COLLECTION
The water cycle• When it is hot Water from the sea evaporates.• The water vapour condenses into tiny drops and
form clouds.• When the clouds are cold, it rains or snow.• The rain or snow falls into the sea.
When the water turns into a gas
Precipitation
Water on Earth is always changing state and place. The water cycle.
EVAPORATION
• When the Sun heats water, water vapour rises.
CONDENSATION
• When the water vapor cools, it turns into water drops and form clouds.
PRECIPITATION• The wind moves the clouds. When the clouds
cool, water from the clouds falls as rain. If it is very cold, the water freezes and falls as snow. Rain and snow are both types of precipitation.
COLLECTION• The water that falls to the ground eventually goes
into rivers. It can travel to the rivers across the surface of the Earth or underground. Rivers take the water back to the ocean and seas.
•Now the cycle begins again.
