Cumulus Cloud and Dew Point
Questions for Making Clouds Grow Activity
Activity 4.4: Part 1
1. Set the dew point to 20°F.
When the temperature is 35°F, what is the altitude of the cloud? 3400
At what temperature does a cloud form at 9500 feet? 62 degrees
2. Set the temperature to 70°F.
What happens to the altitude of the cloud as you raise the dew point from 20°F to 65°F? goes down
Why? Cool air is unable to penetrate clouds above due to subsidence inversion.
3. Based on your observations, what is more important to determining the altitude at which the cloud will form; the actual temperature or the relationship of the temperature and dew point? Relationship of temp and dew point
Why? Because both the temp and dew point allow to accurately measure the height of any cloud, rather trying to use one observation by itself.
Activity 4.4: Part 2
4. Move the bottom 3 temperature dots (which are red) to the right (increasing the temperature), each about 10°C (one grid line).
What happens to the cloud? It gets bigger and increases in height
5. Now move the bottom 2 dew point dots (which are blue) to the right, about 5°C.
What happens when you increase the 3rd dew point dot 10°C (move it to the right)? Precipitation occurs
What does this indicate to you? The maximum temp and dew point combination that allows the cloud to hold any water.
6. Let's look at how temperature and dew point at higher altitudes affect the towering cumulus. Move the temperature dot at 300 mb pressure to about -50°C.
What happens? Height of cloud increases
7. Now move the 3rd temperature dot from the bottom to 10°C.
What occurrence do you observe? Height of cloud decreases
What happens if you then increase the temperature at 300 mb pressure again?
Precipitation stops and cloud height decreases
8. Move the temperature dot at 700 mb pressure to about 10°C; it should be to the right of the pink line on the graph.
What happens? Cloud disappears and only has a small one left
9.
Activity 4.4: Part 1
1. Set the dew point to 20°F.
When the temperature is 35°F, what is the altitude of the cloud? 3400
At what temperature does a cloud form at 9500 feet? 62 degrees
2. Set the temperature to 70°F.
What happens to the altitude of the cloud as you raise the dew point from 20°F to 65°F? goes down
Why? Cool air is unable to penetrate clouds above due to subsidence inversion.
3. Based on your observations, what is more important to determining the altitude at which the cloud will form; the actual temperature or the relationship of the temperature and dew point? Relationship of temp and dew point
Why? Because both the temp and dew point allow to accurately measure the height of any cloud, rather trying to use one observation by itself.
Activity 4.4: Part 2
4. Move the bottom 3 temperature dots (which are red) to the right (increasing the temperature), each about 10°C (one grid line).
What happens to the cloud? It gets bigger and increases in height
5. Now move the bottom 2 dew point dots (which are blue) to the right, about 5°C.
What happens when you increase the 3rd dew point dot 10°C (move it to the right)? Precipitation occurs
What does this indicate to you? The maximum temp and dew point combination that allows the cloud to hold any water.
6. Let's look at how temperature and dew point at higher altitudes affect the towering cumulus. Move the temperature dot at 300 mb pressure to about -50°C.
What happens? Height of cloud increases
7. Now move the 3rd temperature dot from the bottom to 10°C.
What occurrence do you observe? Height of cloud decreases
What happens if you then increase the temperature at 300 mb pressure again?
Precipitation stops and cloud height decreases
8. Move the temperature dot at 700 mb pressure to about 10°C; it should be to the right of the pink line on the graph.
What happens? Cloud disappears and only has a small one left
9.