Mission 1 - Wayward Water! – Explore the Hydrosphere
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Our GeoGarage experiment staff demonstrate an important fact in nature: that when we cool water vapor, clouds form due to a process called condensation. As air moves upward, it cools and its pressure decreases. The cloud we see is the formation of water droplets. As the air continues to rise and cool, these droplets form larger drops until they become so large that it begins to rain, snow, sleet or hail - depending on the temperature.
If you stay outside very long, you will see a variety of types of clouds in the skies over Oklahoma.
Clouds form in a variety of shapes and styles based on their altitude, the amount of water vapor in the atmosphere, and speed and the character of various wind currents which interact with one another in our atmosphere. As air continues to rise, it encounters fast air currents which can move the air far, far away.
As water vapor increases altitude, at some point it reaches air below the freezing point of water, at which point it changes to a solid - forming ice crystals.
High, wispy clouds called cirrus are made up of these tiny frozen ice crystals, and often travel thousands of miles. Is it likely that our water drop is in these clouds? No, probably not, as they contain frozen ice coming from hundreds or even thousands of miles away! We can eliminate this one.
There are also puffy, fair weather clouds called cumulus forming at lower levels. These puffy, rain-free clouds form at lower altitudes, then dissipate in the air. Sometimes cumulus clouds are called altocumulus if they are high up, or cirrocumulus if they are very high up. Cirrus and cumulus clouds are not normally associated with precipitation.
To find our water droplet, we need to find water vapor condensing into droplets large enough to be detected! Let's look for clouds capable of forming precipitation!
Precipitation is the falling of solid ice or liquid water back to Earth as water condenses. Water droplets get heavier as they condense, and are pulled back to Earth by gravity. We call this precipitation that is falling as liquid water, rain. Precipitation that is falling as frozen ice crystals is called snow. Sometimes, rain freezes in thunderstorms into balls of ice we call hail.
The moisture levels are high here because a boundary between two air masses, called a "front" is approaching. Here, water vapor rapidly rises and condenses forming large dark rain clouds, or cumulonimbus clouds. Here we should look for our water droplet, as nearby water vapor at low altitudes is rapidly changing back to water, and will fall back to Earth again soon.
Once you are finished, click "Next Lesson" to reload Estemite into the Terravator for the next leg of the journey!
Knowledge Scanner: Mission 1 Lesson 3
QR: No rocks, minerals or fossils are linked in this lesson.