Dear Scouter Atom,
Our first night at camp was warm and clear – no clouds in the sky! But when we woke up in the morning, fog had set in over our campsite and across the lake. As the sun came out the fog started to lift and we were left with another clear, warm day. Why does fog only hang around in the morning?
1st Grand Banks Company
There is nothing quite like a misty or foggy morning on the lake. It’s my favourite way to start the day.
Mist and fog are very similar to clouds, but instead of floating high in the sky they are formed closer to the ground.
The air we breathe is full of water. When the air is warm enough, that water hangs around as a gas. But when the air cools down enough, the water condenses into liquid. The water condenses onto tiny particles in the air, such as dust or pollen. Even though the air is even colder higher in the atmosphere, the air is thinner and there are fewer particles for the water to condense onto. These particle clouds then become water clouds.
Think about the fog that shows up on your mirror when you take a hot shower or bath. When the warm air comes into contact with your cold mirror, the water is cooled down very quickly and condenses on the surface of the mirror.
Clouds form much the same way – when the air cools down enough, the water condenses onto dust particles and creates a cloud. Fog and mist are clouds that form near the ground.
The ground loses heat easily. When the sun goes down, the ground radiates its heat and quickly cools down. Over the course of the night, the ground gets colder, and the air close to the ground is cooled down. Water vapour in the air begins to condense. If enough water condenses, the air becomes saturated with water and a cloud will form. Humid weather indicates that there is already a lot of water in the air, so fog and mist are more likely to form.
When the sun comes out and warms up the ground and the air close to the ground, the fog will start to burn off. The water in the fog cloud starts to evaporate and the day will break clear and warm, ready for another great Scouting adventure.
You can make a cloud for yourself at home with a few easy steps.
You will need:
- A glass jar or tall glass
- Warm water
- A small bowl that sits on top of the jar or glass
- Add the warm water to the glass. Swirl the water around a bit to warm up the glass and prevent water from condensing on the sides.
- Put the bowl on top of the jar or glass, and add a few ice cubes.
- Let the system sit. Watch as the water condenses.
- To really get the cloud going, take the bowl off after about 30 seconds and spray a bit of hairspray into the jar. Put the bowl of ice back on top and watch your cloud form.
- Take the bowl of ice off the top and watch your cloud rise up and out of the jar.
Until next time,
Scouter Atom is a Colony Scouter with a passion for STEM adventures. There is no question too small, no question too large – if you have a question, Scouter Atom has an answer. Send your questions to firstname.lastname@example.org.