*** This is a sample DataStreme Activity ***

*** The first part of the Activity is provided to participants via the pre-printed pages in the DataStreme Study Guide, Part B: Applications. The second part of each Activity utilizing real-time meteorological data is provided via this DataStreme Homepage. Twice a week this portion of the activity is delivered to the DataStreme Homepage during the course. ***

Name:______________________________ . . . . . . . . . . . . . . . . . . . . Date:_______________

Activity 1A:

AIR TEMPERATURE PATTERNS

Educational Outcomes:

What is the outdoor temperature? What clothes should we wear? What is the weather, including temperature, going to be? Should we go ahead with our planned outdoor activity? Should we make that trip today? Is it warmer or colder in other parts of the country?

The analysis of temperatures reported on weather maps can help us answer these and other weather-related questions. The patterns of temperature revealed by isotherm analysis show regions where temperatures are relatively high and low, and where temperature changes from place to place are dramatic or gradual over short distances.

After completing this activity, you should be able to:

• Draw lines of equal temperature (isotherms) to show the pattern of temperatures across the nation at map time.
• Locate regions of relatively high and low temperatures on the same map.

Investigations:

1. Temperature patterns are found on weather maps by drawing lines representing certain temperatures. These lines are called isotherms because every point on the same line has the same temperature value. Each isotherm separates temperatures having higher values than the line from temperatures having lower values.

   The following map shows temperatures in degrees Fahrenheit at various locations. Assume each number centers on the location it represents. A 60- degree isotherm has been drawn and labeled. Complete the 70-degree isotherm shown. Also, draw the 80-degree isotherm. Write the appropriate values at both ends of each isotherm.

   

2. Isotherms are drawn at regular intervals. An interval is the difference in temperature value from one isotherm to the next. On this map, the interval is _____ Fahrenheit degrees.

3. The accompanying DataStreme Plot of Surface Temperature map shows temperatures for a particular time on 19 September 1996. The 90 and 50 Fahrenheit-degree isotherms have already been drawn, and a partial 60-degree analysis has been done. The 70-degree isotherm has been started. Complete the 70-degree analysis. Then do the 60-degree analysis in the western US. Lastly draw the 80-degree isotherm to complete the temperature analysis.

4. On this map the temperature pattern is dominated by relatively low temperatures in the [(Rocky Mountain) (Gulf Coast )] States and warm temperatures in the [(Rocky Mountain ) (Gulf Coast)] States.

DataStreme Activity 1A:

AIR TEMPERATURE PATTERNS

Do Now:

1. Print this file.
2. Print the Daily Summary file.
3. Print the Image 1 and Image 2 files.

To Do Activity:

1. Read Chapter 1 in STUDY GUIDE, Part A: Narrative.
2. Go to STUDY GUIDE, Part B: Applications. Start Activity 1A. (pre-printed portion)
3. Return here (Tuesday - Activity A File) when told to do so.

Go to STUDY GUIDE Now

WELCOME BACK: Procedure continued from STUDY GUIDE

5. The Image 1 map is a Plot of Surface Temperature for 0Z, 8 OCT 96. The highest reported temperature on the map is ____ degrees F. The lowest is ____ degrees F.
   

6. Using a 10-F degree interval, complete the listing of isotherms that would appear at least once on this map: 40, ___, ___, ___, ___, ____, _____.

7. Working through the steps a, b, and c that follow, draw these isotherms on this map to determine the temperature pattern that existed at the time observations were made.

   1. Start drawing the 70-degree isotherm by determining the location along the Atlantic coast near the GA/SC state border where the temperature is probably 70 degrees F. Continue the line westward, keeping temperatures below 70 degrees on the higher latitude (northern) side of the isotherm and those above 70 degrees on the lower latitude side. This isotherm heads along the Gulf Coast, into the lower Mississippi Valley, then northward across the Plains to the Northwest, and exits the U.S. data field at the Washington coast.

   2. Before drawing the 60-degree isotherm, scan northward along the Atlantic coast from where you started the 70-degree isotherm until you find temperatures that change from the 60s to the 50s. This indicates the location of the 60-degree isotherm. Start the isotherm and draw it generally southwestward, separating lower and higher temperatures.

   3. To complete the temperature analysis of this map, draw all remaining isotherms whose values are listed in #6 above. Keep in mind that more than one isotherm with the same value can appear on the same map, and an isotherm is drawn only if temperatures above and below its value appear on the map. The large change in temperature values in Southern California is a reflection of the terrain, going from the cool coast, over the mountains to the interior desert.

8. Image 2 is the Surface Data Plot for 0Z 8 OCT 96. Compare your isotherm pattern to that analyzed by the computer based on a data set that includes a different number of station reports. In general, the 70-degree isotherm, for example, [(does) (does not)] appear in the same area on both maps. The computer generated isotherms are usually [(more) (less)] jagged than a hand-drawn analysis.

9. The map shows that generally surface air temperatures [(increase ) (decrease)] with an increase in latitude.

10. Locate regions on the map where isotherms are relatively close together as in the Texas to Indiana area. These are regions where temperature changes are relatively [(large) (small)] along lines perpendicular to the isotherms. This area is associated with [( the high pressure center) (a cold front)].

11. As noted by the wind directions along and north of the cold front, the cold air is moving generally towards the [(south) (north)]. Label the cold front by adding triangles on the side of the front toward which the cold air is moving. A warm front is across Florida. Add semicircles to indicate the movement of the warm air. The symbols are attached to the [(south) (north)] side of the front line.

12. The isotherms from northern Texas to western New York are generally [( parallel) (perpendicular)] to the cold front. The isotherms across Florida are also relatively [(close together and parallel) (widely spaced and perpendicular )] to the warm front.