Coastal Winds and Clouds Gizmo Answer Key

Name: Sara Best Date: 09-10-2022 Student Exploration: Coastal Winds and Clouds Directions: Follow the instructions to go through the simulation. Respond to the questions and prompts in the orange boxes. Vocabulary: condensation, convection, convection current, land breeze, sea breeze Prior Knowledge Questions (Do these BEFORE using the Gizmo.) A hot-air balloon contains a propane burner that directs hot air into the interior of the balloon. You can see the flames in the photo at left. 1. What happens when the air inside the balloon is heated? The balloon will ascend as a result of the air expanding. 2. What might happen if the burner was turned off? The balloon will sink when the air inside of it begins to chill. Gizmo Warm-up Have you ever taken a walk along an ocean beach and noticed a refreshing breeze blowing in from the water? The cause of this breeze, called a sea breeze, is related to the reason that a hot-air balloon is able to fly high in the sky. The Coastal Winds and Clouds Gizmo allows you to explore how daily temperature variations are related to sea breezes and other weather phenomena. Click Play ( ), and watch the Gizmo for 24 simulated hours, focusing on the sailboat. 1. Click Pause ( ) when the sailboat starts moving towards the shore. This represents the start of the sea breeze. What time is it? 10 AM 2. Click Play, and then click Pause when the sailboat starts moving out to sea again. This represents the start of the land breeze. What time is it now? 1 AM 3. Click Play, and now observe the clouds for a day. What do you notice? Early in the morning (5 AM) and late in the afternoon (2 PM), clouds emerge. The morning clouds go toward the coast, while the afternoon clouds move toward the ocean. Activity A: Get the Gizmo ready: Temperature and wind ● Click Reset ( ). ● Turn on the Weather probe. Question: How is wind speed and direction related to air temperature? 1. Think about it: Imagine a pocket of air over the land (“land air”), and another pocket of air over the ocean (“ocean air”). A. Which air pocket would you expect to heat up more during the day? Land air Why? It warms up more in a day than the ocean does B. Which air pocket would you expect to cool down more at night? Land air Why? At night, it becomes cooler than the ocean. 2. Gather data: Check that the time is 6:00 A.M. Drag the Weather probe so that it is on the ocean’s surface (Alt. 0 ft) on the left side of the Gizmo, and record the air temperature. Then, repeat with the probe on the land on the right side of the Gizmo. Finally, move the probe to the land-sea boundary and record the type of breeze (sea or land breeze) and wind speed. Record data for each time listed in the table below. (Note: Stopping the simulation at the exact time is not necessary, just get close.) 6:00 A.M. Ocean air temperature (°C) 68.1 Land air temperature (°C) 60.5 9:00 A.M. 69.2 12:00 P.M. Sea breeze or land breeze? Wind speed (km/h) Land breeze 14.4 mph 68.6 Land breeze 1.2 mph 70.5 77.0 Sea breeze 12.0 mph 3:00 P.M. 72.1 84.7 Sea breeze 24.1 mph 6:00 P.M. 71.2 79.7 Sea breeze 16.2 mph 9:00 P.M. 70.4 74.6 Sea breeze 8.3 mph 12:00 A.M. 69.3 69.7 Sea breeze 0.7 mph 3:00 A.M. 68.8 64.6 Land breeze 7.6 mph Time 3. Calculate: For both the ocean air temperature column and land air temperature column, find the temperature range by subtracting the lowest temperature from the highest. A. How much does the temperature over the ocean change in one day? 3.9 degrees F B. How much does the temperature over the land change in one day? 24.2 degrees F 4. Analyze: Compare the air temperatures to the breezes. A. At 6:00 A.M., where was the warmest air? Over the ocean B. At 6:00 A.M., in which direction did the breeze blow? From the land to the ocean C. At 3:00 P.M., where was the warmest air? Over the land D. At 3:00 P.M., in which direction did the breeze blow? From the ocean to the land 5. Summarize: What is always true when there is a land breeze? When ocean air is warmer than land air, land breezes occur. What is always true when there is a sea breeze? When land air is warmer than ocean air, sea breezes blow. 6. Draw conclusions: In general, the land changes temperature much more rapidly than the ocean. How does this fact explain the existence of land breezes and sea breezes? The land tends to be warmer during the day and colder at night than the ocean because the land changes temperature much more quickly than the water does. This causes sea breezes during the day and land breezes at night. 7. Extend your thinking: With the probe placed on the land-sea boundary, monitor the wind speed. Click Pause when the strength of the sea breeze is at a maximum. A. At what time of day is the sea breeze strongest? 3 PM B. Use the Weather probe to measure the land-air and ocean-air temperatures. What are these temperatures at this time? Land = 84.7 degrees F Sea = 72.0 degrees F C. Click Play, and then click Pause when the strength of the land breeze is at a maximum. What is the time? 6 AM D. What are the land- and ocean-air temperatures now? Land = 60.5 degrees F E. The wind changes direction at approximately 9:10 A.M. and 12:10 A.M. What is true about each of these times? The land air and ocean air temperatures are equal at these times Activity B: Get the Gizmo ready: ● Click Reset. ● Turn on the Drifting balloon. Convection currents Question: Why do land breezes and sea breezes occur? 1. Observe: Click Play, and observe the balloon for a period of 48 hours. Pause the simulation whenever the balloon changes direction. Describe what you see in the space below. The balloon drifts clockwise from 12AM-9AM and counterclockwise from 9AM-12AM, moving the fastest at 3PM 2. Analyze: During what time period does the balloon drift in a clockwise direction? 12 AM-9 AM During what time period does the balloon drift in a counterclockwise direction? 9 AM-12 AM 3. Gather data: The diagram at right shows the scene at 6:00 A.M. Use the Weather probe to find the temperature at each of the numbered locations. Label the temperature at each of the numbered locations. Hand draw on each circle or click on the image and select EDIT. ✏️ Next, find the wind direction between the points on the diagram. Draw arrows to represent the movement of air. Which points represent the lowest and highest temperatures on the diagram? Highest? Point 2 Lowest? Point 3 4. Analyze: In which direction is the hottest air in the diagram moving? Upward In which direction is the coldest air in the diagram moving? Downward This pattern—in which low-density, hot air rises while high-density, cold air sinks—is an example of convection. The resulting circular flow of air is called a convection current. 5. Gather data: Click Play, and then click Pause at 3:00 P.M. Use the Weather probe to find the temperature at each of the numbered locations. Label the temperature at each of the numbered locations. Hand draw on each circle or click on the image and select EDIT. ✏️ Find the wind direction between the points as you did before. Draw arrows to represent the movement of air. Which points represent the lowest and highest temperatures on the diagram? Highest? Point 1 Lowest? Point 4 6. Analyze: In which direction is the hottest air in the diagram moving? Upward In which direction is the coldest air in the diagram moving? Downward 7. Explain: What causes the counterclockwise flow of air in the afternoon? Since the air over the water is cooler than the air over land, a counterclockwise convention current is created when cooler ocean air rises in. 8. Observe: Place the Weather probe at the land-sea boundary, and click Pause when the sea breeze is strongest. A. What do you notice in the sky at this time? Thunderstorms and clouds B. Click Play, and then pause the simulation when the land breeze is strongest. What do you notice in the sky now? Lightning storms and clouds 9. Explain: Clouds often form when a large mass of warm, moist air rises quickly and cools, resulting in condensation of the water vapor. Based on this statement, why do clouds tend to form around 3:00 P.M. and 6:00 A.M.? Strong convection currents are present at both periods, carrying warm air upward where it cools and condenses to produce clouds.