## Assignment

(See Directions)

A wind is blowing from left to right over the mountain. Adjust the initial temperature and vapor pressure of the air so that a cloud will form at 1 km - 1.2 km (i.e., the altitude of cloud base is between 1 km and 1.2 km).

Then write your answers to the Questions below on another sheet of paper, using the simulation to answer the questions.  When done, click BACK on your browser and answer the questions in the assignment MtnSim_Humidity.

## Questions

1) Start with a vapor pressure of 10mb. Enter a temperature (between 0 C and 40 C) that will cause a cloud to form.

2) Start with a vapor pressure of 10mb. Enter a temperature (between 0 C and 40 C) that will not cause a cloud to form.

3) Given an initial air temperature of 28 C, enter an initial dew point temperature (between 0 C and 40 C) which will cause a cloud to form below 500m.

4) Given an initial air temperature of 28 C, enter an initial dew point temperature (between 0 C and 40 C) which
will cause a cloud to form above 1000m.

5) Given an initial air temperature of 28 C, enter an initial dew point temperature (between -10 C and 40 C)
which will cause no cloud to form.

6) Given an initial air temperature of 20 C, enter an initial water vapor pressure (between 0 mb and 24 mb)
which will cause instantaneous cloud formation.

7) Given an initial air temperature of 20 C, enter an initial water vapor pressure (between 0 mb and 24 mb)
which will cause cloud formation above 1000m.

8) Given an initial air temperature of 20 C, enter an initial water vapor pressure (between 0 mb and 24 mb)
which will cause no cloud formation.

## Directions

Setting Initial Conditions:
Use the scrollbars in the simulation to set the initial temperature and water vapor pressure. As you scroll the leaf will move on the Vapor Pressure vs. Temperature graph. The numerical values are shown in the digital displays to the left of the scrollbars.

The following exercises are provided to help you learn to use the simulation.

Warm-up Exercise 1 - Setting Initial Conditions

Scroll up to the simulation and set the initial temperature to 20 degree C and initial water vapor to 10 mb.

Warm-up Exercise 2 - Using the Controls

• Run the Simulation by clicking on the "Start Wind" button.
• Click the "New Trial" button and then choose different initial conditions and press "Start Wind" again.
• After multiple attempts, clear the graphs using the "Clear Graphs" button.
• Try changing the speed of the simulation by scrolling the "Wind Speed" scroll bar.
Warm-up Exercise 3 - Showing the Log
Click on the "View Log" button and you will see the results of your experiment. Close the Log Window when done.