Air masses over North America, illustrating their source regions and movement directions.

It looks like you've uploaded a lab exercise titled "Air Masses, Fronts and the Middle Latitude Cyclone" from ESC 120 Earth Science Labs, specifically Lab Exercise Ten. The task is to label the air masses on Figure 10-1 (a map of North America) and list their source regions and characteristics.

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✔ Understanding Air Masses

An air mass is a large body of air with relatively uniform temperature and humidity characteristics. These are classified based on two factors:

1. Source Region: Where the air mass forms.
2. Temperature and Moisture Characteristics:
- c = continental (dry)
- m = maritime (moist)
- P = polar (cold)
- T = tropical (warm)

So:
- cP = continental polar → cold and dry
- mP = maritime polar → cold and humid
- cT = continental tropical → hot and dry
- mT = maritime tropical → warm and humid

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🗺️ Labeling the Air Masses on the Map

From the diagram in Figure 10-1:

#### 1. cP (Continental Polar)
- Location: Northern Canada (upper left)
- Characteristics: Cold and dry
- Arrow: Blue arrow moving southward from northern Canada toward central US

#### 2. mP (Maritime Polar)
- Location: North Pacific Ocean (west coast) and North Atlantic Ocean (east coast)
- Characteristics: Cold and humid
- Arrows: Two blue arrows coming from the Pacific and Atlantic Oceans into western and eastern parts of North America

#### 3. cT (Continental Tropical)
- Location: Central Mexico / Southern U.S. (south-central region)
- Characteristics: Hot and dry
- Arrow: Red arrow coming from the southern interior of the continent

#### 4. mT (Maritime Tropical)
- Location: Gulf of Mexico and Caribbean Sea (south)
- Characteristics: Warm and humid
- Arrows: Two red arrows coming from the Gulf of Mexico and Atlantic Ocean, moving northward into the southeastern U.S.

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✔ Completed Table

Here is the filled-in table as requested:

| Name | Source Region | Characteristics |
|------|----------------|------------------|
| cP | continental polar region e.g. Northern Canada | cold and dry |
| mP | maritime polar region e.g. Pacific/Atlantic | cold and humid |
| cT | continental tropical region e.g. Central America | hot and dry |
| mT | maritime tropical region e.g. Gulf of Mexico/Caribbean | warm and humid |

> 🔍 Note: Although the table already has the correct information, the task is to label the map with these names (cP, mP, cT, mT) and then fill out the table — which you’ve already done correctly.

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✔ Final Answer Summary

On the map (Figure 10-1):
- Label the blue arrows from the north:
- Left side: cP (continental polar)
- Right side: mP (maritime polar)
- Label the red arrows from the south:
- Central southern U.S.: cT (continental tropical)
- Gulf of Mexico and Atlantic: mT (maritime tropical)

✔ The table is complete and accurate as provided.

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Let me know if you'd like help with Lab Activity Two (Fronts and Mid-Latitude Cyclones), or if you want this explained visually!