Geography 1001 Continuing Education Name________________________ Exercise 3 Insolation and the atmosphere. Refer to Ch. 4 (Energy Balance Essentials) in your text and lecture notes on Atmosphere. Of the solar energy that reaches the earth’s surface, considerable amounts may be reflected. The energy that is not reflected is absorbed and helps to warm the surface atmosphere. Different surfaces have differing albedos, or “reflectiveness.” Consider an airplane that is fitted with a solarimeter, an instrument used to measure solar radiation (i.e., short wave) that is reflected from the surface of the earth. The aircraft makes five runs over different surfaces recording the albedo. 1. Using the recorded results shown below, calculate the average albedo of each surface, and write it at the bottom of each column. Thick Forest Green Fields Dry Plowed Fields Grass Freshly Fallen Snow Old Snow 8.5% 9.2% 3.5% 8.0% 4.8% 12.2% 11.8% 9.5% 13.5% 11.0% 24.0% 25.2% 20.8% 24.1% 22.9% 23.0% 17.0% 30.0% 24.0% 25.0% 95.0% 75.0% 80.0% 75.0% 85.0% 55.0% 70.0% 65.0% 65.0% 60.0% Water (Solar Altitude >40°) 2.0% 3.5% 3.5% 4.0% 3.5% Water (Solar Altitude 5°-30°) 35.0% 37.5% 32.5% 30.0% 50.0% Average 2. With reference to the above results, name the two best reflecting surfaces. a._________________________________ b._________________________________ 3. What are the two best absorbing surfaces? a.___________________________________ b._________________________________ 1 Temperature Land vs. Water Heating Differences. Refer to Ch. 4 and notes from Unit 4 Lecture. In addition to the seasons, latitudinal differences, and altitude, a location’s proximity to a large water body may have a strong affect on temperature. We refer to this as the “marine” or “maritime” effect. In contrast, a large landmass with little marine influence has the opposite effect on temperature and is said to be “continental.” 4. List four reasons why water bodies do not heat up or cool down as much as continental areas of similar latitude. a. _____________________________________________ b. ______________________________________________ c. _______________________________________________ d. ________________________________________________ Daily Cycle of Temperature. Refer to Section 4.3.1 and Figure 4.14 of your text along with your notes from lecture 4. 5. At what time of day does maximum insolation (not temperature) normally occur? 6. The maximum daily temperature generally lags behind the time of maximum insolation. Why? Explain your answer in terms of net radiation. 2 Global Temperature Patterns. Climate data, such as temperature can be depicted on isoline maps. Isolines are defined as lines that connect points of equal value. Your textbook has a series of isoline maps showing lines of equal temperature (isotherms). These are figures 4.29 through 4.32. After reviewing Lecture 4C, answer the following questions with reference to these maps. 7. Do the isotherms in figure 4.30 have a more predominant north/south or east/west orientation in the southern hemisphere? What causes this general orientation? 8. What is the general relationship between latitude and mean annual temperature (fig. 4.29