There
are lots of fun weather experiments that you can do in
the home or in the classroom. Here are some ideas. Make
sure you always have an adult with you when trying out
these experiments.
Make a tornado in a jar
What you will need:
- A clear jam jar or similar see-through
container with a screw-on lid
- Washing-up liquid
- Food colouring
Fill up the container with water then
add a few drops of the washing-up liquid and a few drops
of the food colouring. Tightly screw on the lid.
Swirl the container around in a circle
several times and then stop. Inside you should see what
looks like a tornado. It will slowly fade as it reaches
the top of the container.
Tornadoes in the real world form in a
similar way. A tornado is a violently rotating column of
air, often touching the ground, and is created by a special
type of rotating thunderstorm called a supercell.
Make a cloud in a glass
What you will need:
- A clear glass or similar see-through
container
- Warm water
- Ice
- Metal dish
Place the ice into the metal dish and
pour a small amount of warm water into the bottom of the
glass. Once the dish is really cold, place it on top of
the glass. Watch the inside closely. You should see a 'cloud'
form near the top of the glass.
This is the way clouds form in the real
world. Warm, moist air like that in your glass, is cooled
(your ice). When it is cooled it condenses into tiny water
droplets, which appear as clouds.
Weather fronts
What you will need:
- A large, clear tank
- Warm and cold water
- Two plastic cups
- Small stones
Fill the tank with normal water and leave
this for a few hours to come to room temperature.
Place a few small pebbles in each of the
two cups to act as weights. In one of the cups place some
hot water and a few drops of red food colouring. Fill the
other cup with very cold water and add some blue food colouring.
Place the two cups into the water at the same time, one
at either end of the tank - the pebbles should hold the
cups at the bottom. Carefully watch how the two different
coloured waters move. You should see that the warmer red
water should raise to the top, and the cooler blue water
should sink to the bottom.
Much of our weather is caused by the interactions
of different air masses. Warm air (shown by your warm red
water) is less dense than cold air (cold blue water), so
warm air rises and warm air exerts less pressure than cold
air. As air cools, it becomes denser, so it sinks and also
exerts greater pressure.
Water
cycle in a bag
What you will need:
- A large bowl
- A small yogurt pot or plastic cup
- Clingfilm
- Water
- Small weight
- Sunny window sill
Take the large bowl and fill it with several
centimetres of water. Place your small pot in the centre
of the bowl of water, making sure not to get any water
inside it. Cover the large bowl with clingfilm and fasten
this down securely to the side of the bowl. Put a weight
on top of the clingfilm, over the centre of the small pot
to push the clingfilm down into it slightly. Place your
experiment on a warm sunny window sill and leave for a
few days.
You should find that the heat of the sun
evaporates the water, which rises, condenses on the cool
plastic, and falls into the small container. This is a
small version of what happens in the real water cycle.
Measuring
a puddle
What you will need
- A puddle
- A piece of chalk
Choose a day then there has been rain
overnight and the rest of the day is expected to be dry,
warm and sunny.
Choose a puddle and first thing in the
morning use a piece of chalk to draw around the puddle.
A few hours later go back and draw around your puddle again.
Repeat this several times during the day.
You should find that the puddle slowly
shrinks during the day as the water evaporates. |
