# lab repot

Topics: Wind, Dune, Rain shadow Pages: 3 (537 words) Published: November 25, 2013
Week Four Deserts Lab Report

Answer the lab questions for this week and summarize the lab experience using this form.

Carefully read ch. 15 of Geoscience Laboratory.

Complete this week’s lab by filling in your responses to the questions from the Geoscience Laboratory. Select answers are provided for you in red font to assist you with your lab work. Although you are only required to respond to the questions in this worksheet, you are encouraged to answer others from the text on your own.

Questions are from Geoscience Laboratory, 5th ed. (p. 268–278), by T. Freeman, 2009, New York, NY: John Wiley & Sons. Reprinted with permission.

Lab Questions

15.4.Given principles 1–4 on page 265, explain the occurrence of the two contrasting climates illustrated in Figure 15.5. The two climates are very different because the Windward side is located at a much higher altitude that the Leeward side. When the cooler moist air is brought over the mountain, it creates a rain shadow. However, the humidity usually decreases because of the heat.

15.8.Why are nights in arid lands surprisingly cold? Hint: Think of a feature of the atmosphere that holds daytime heat during the night. In the evening, the heat blanket disappears. The heat comes from the sun, so when the sun sets, so does the heat. There is little to nothing on the terrain to hold the heat in, so it just vanishes and allows the nights to be cooler.

15.14.What is the prevailing wind direction indicated by the barchan dunes in Figure 15.14?

15.16.Notice in Figure 15.14 that some of the dunes are not perfectly symmetrical like that shown in Figure 15.13. (A) Describe this asymmetry, and (B) try to explain it. Hint: Study the caption to Figure 15.13A. The sand hills are called the barchans dunes. These dunes are created by wind with a nominal flow of sand. They are crescent shaped and also produce a constant flow of sand. The symmetry is developed because of...