An adventure in STEM and brought to you by Family Strengths Network and the Los Alamos STEAM Lab – credit JoAnna O’Neill
Clouds
Most days when you look up into the sky you can see a variety of different types of clouds. Even when we can’t see them, clouds affect our daily lives in a number of different ways. Clouds are important components of the complex global weather system and play a key role in Earth’s water cycle. Clouds have dramatic effects on climate and weather and can influence the locations and severity of floods and droughts as well as affect the temperature of the planet as a whole. Gaining a better understanding of clouds allows scientists to better predict severe storms, global freshwater distribution, and the course of climate change.
How are Clouds Formed?
Water can exist in three phases (solid, liquid, and gas) and is the primary component of all clouds. The water that makes up clouds can exist in any of its three phases as ice crystals, water droplets, and water vapor. The main source of the water vapor necessary for the initial steps of cloud formation comes from evaporation (the process of turning from a liquid into a gas or vapor) as well as transpiration (the release of water by plants).
As the sun warms the Earth’s surface, water vapor is introduced into the atmosphere through evaporation from bodies of water such as oceans and lakes, and transpiration from Earth’s many plants. As warm air rises, it brings water vapor with it. The warmer the air, the more moisture it can hold and the colder the air, the less water vapor it can hold. If the air becomes cold enough, it will reach a state called supersaturation (when more water vapor is present than needed to produce saturation) and some of the water will transition back into a liquid or solid state. Water molecules will form around tiny particles such as dust, pollen or smoke suspended in the atmosphere. These particles are called condensation nuclei and serve as a starting point for the formation of tiny water droplets and ice crystals from water vapor. As this process is repeated billions and billions of times, these newly formed ice crystals and water droplets will clump together to form a visible cloud. Once a cloud becomes large and full enough, it will release the water back down to the Earth as precipitation in the form of rain, snow, sleet, or hail.
Types of Clouds:
Clouds can have many different characteristics including a wide variety in appearance and atmospheric height. A cloud’s qualities are dictated by the elements available in the direct environment, including the amount of water vapor, temperatures at that altitude, wind, and the interplay of other air masses. Clouds are formally classified by both appearance and height of the cloud base. Information on the 10 basic types of clouds and how they are classified can be found here: https://www.weather.gov/jetstream/basicten
Cloud Facts:
- Clouds reflect sunlight but also absorb infrared energy. Reflecting light from the sun is what gives them their typical white appearance.
- Clouds appear whiter if the water droplets contained in them are smaller. This happens as the result of more condensation nuclei or aerosols in the clouds.
- Clouds can appear gray when they are either very full of water or if there are so many clouds in the area that they are casting shadows on eachother.
- The average cumulus fair weather cloud can weigh more than a million pounds and a lively thunderstorm cloud can pack billions to trillions of pounds of water into a tiny fraction of the sky.
- In meteorology, the study of clouds is called nephology and a person who studies clouds is known as a nephologist.
- A cloud will float as long as the air that the water and air it is made of is warmer than the air surrounding it.
At Home Experiments
For local families, supplies can be picked up at Family Strengths Network during June (2021)
Experiment 1: Cloud in a Jar
Video Tutorial:
Materials:
- Glass jar with a metal lid
- Hot/boiling water
- Ice
- Hairspray
Instructions:
- Start by pouring the hot water into the jar carefully until it is about halfway full. Swirl it around to heat up the side of the jar.
- Turn the metal lid upside down and place it on the top opening of the jar.
- Place your ice cubes inside the upside down lid.
- Wait about 30 seconds to 1 minute.
- Quickly and carefully remove the lid holding the ice cubes and briefly spray hairspray into the jar.
- Immediately replace the lid and ice cubes to seal off the jar opening.
- Observe the cloud form.
- Remove the lid to release the cloud when you are ready. Watch as it rises up and disappears into the air outside of the jar.
How It Works:
This experiment mimics the natural cloud formation process described above. As hot water is added to the jar, some of it turns to its gaseous form, water vapor. As this vapor rises to the top of the jar, it encounters the cold lid filled with ice cubes. Upon contact with the lid, the water vapor condenses as it cools down. However, a cloud will not form unless the water vapor has something to condense to. The hairspray added to the jar serves as the condensation nuclei that allow a cloud to form and become visible within the jar.
Experiment 2: Rain in a Jar
Video Tutorial:
Materials:
- Glass jar
- Food coloring drops
- Shaving Cream
- Room temperature water
Instructions:
- Fill the glass jar about 2/3 of the way full with water.
- Fill the rest of the jar with shaving cream to form a fluffy cloud at the top.
- Drip your food coloring onto the shaving cream until the first drops of rain (food coloring) make their way through your cloud (shaving cream) and are released into the water below.
How it Works:
In this experiment, the shaving cream serves as a cloud, the water as the atmosphere, and the food coloring as moisture entering the cloud during cloud formation that will eventually leave in the form of precipitation. As the food coloring is dropped into the shaving cream, the shaving cream cloud becomes saturated and mimics how clouds grow and become heavier until they reach a point where they can no longer hold onto that much water. When clouds reach this point, they will release water as rain or other forms of precipitation in a similar way to how the shaving cream releases the food coloring into the water below after enough drops are added.
Thank you for joining us!