quiz answers
1) What does wind chill mean?
Wind chill is how cold the weather makes you feel, not the real temperature outside. It could be -15�C but feel like -30�C because of the wind chill.
Why does this happen? Why do you feel colder?
Put your hand about 15 cm in front of your face. Now blow on it. Your hand feels cooler, even though the temperature of the room hasn't changed. That is like wind chill.
Wind chill is how quickly your skin loses heat because of the temperature and the wind. Scientists use math to find the wind chill. They use the air temperature and the wind speed in a math formula. We don't need to learn how to calculate wind chill, but we do need to know what it is every day, so we can dress for it when we go outside.
Listen to the weather forecast every morning to check. The weather person will say something like: "The temperature today will be minus 15 degrees with a wind chill of minus 30."
This means that, even though the temperature is -15�C, it will feel like -30�C, so dress for -30�C!
(They don't say "the wind chill is minus 30 degrees" because wind chill is not a real temperature.)
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gloves or mittens? Why?
Mittens will keep your hands warmer. With mittens, there is less surface area for the cold air to attack. There is more air space in mittens for air to circulate and to trap warm air. Also your fingers stay together and share their heat with each other.
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When we are outside, we lose a lot of body heat. Most of the body heat that we lose (90%!) gets lost through our heads. If we wear a hat, we keep the heat longer in our body. This also means that our hands and feet stay warmer longer too.
When you choose a hat, get one that also covers your ears. Or you can wear a hat and ear muffs. (See question #5 to learn why you need to cover your ears.)
Also, wear a scarf to keep your neck warm. When it's extra cold, you can pull the scarf up to cover your nose and mouth.
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Winter boots not only keep your feet warm, they also keep your feet dry. Winter boots are insulated, which means they keep the heat in longer. Get water-repellent boots so the slush and snow won't leak through. Winter boots will also give you more traction (or grip) when you are walking on icy sidewalks.
Remember to wear warm socks, too.
"Duh," says Ms. Lam. "Is that a good question? Nope."
o Running shoes are not insulated -- they won't keep your feet warm.
o AND if you wear extra socks, what will happen is that your feet will be squeezed in your running shoes and that is not good for the blood circulation in your feet.
o If the blood circulation is bad in winter, your feet will actually get colder faster, and there is a greater chance of frostbite!
5) What is frostbite?
What
o Damage to your skin when it freezes. Mild frostbite is called "frostnip".
When
o It's very cold and you stay outside for a long, long time
o It's very cold outside and your skin is not protected
o It's extra-freezing-cold outside and you are outside, even for a short time.
Why
o When your skin is out in the cold, your blood vessels contract (squeeze) and your blood flow slows down. The blood has a harder time getting to the end parts of your body like your fingers or toes. If your skin isn't properly protected, it can freeze.
Where
o The parts of your body that can get frostbite the easiest are:
-- fingers
-- toes
-- ears
-- tip of your nose
What does it look and feel like?
o White or extra-pale patch on the skin.
o The part gets numb but it can hurt.
What should you do?
o Come inside right away! If you are at school, go to the office for help. They will know what to do.
o If you are home, call an adult for help.
o NEVER RUB the skin that is frostbitten. This can do more damage. It has to be warmed up VERY SLOWLY.
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What do you think this means?
Why do you think it is a good idea?
Dressing in layers means wearing two or three layers of thinner clothing rather than one thick piece of clothing.
Example: At school, wear a T-shirt with a sweatshirt over it, rather than a heavy sweater.
Why is this better? If you are inside and you are too warm, you can just take off your sweatshirt or your T-shirt. If you are only wearing your sweater, you can't take that off.
More importantly, when you're outside, you will be warmer. Layers of clothing give more warmth than one thick garment. Your body heat is trapped between the layers, which becomes a very good insulator.
