*** The first part of the Investigation is provided to participants via the pre-printed pages in the DataStreme Atmosphere Investigations Manual. The second part of each Investigation utilizing real-time meteorological data (Current Weather Study) is provided via this DataStreme Atmosphere website. Twice a week this Current Weather Study is delivered to the DataStreme Atmosphere website during the course. ***
*** The following pre-printed portion of the Investigation would be provided to each participant as the Weather Studies Investigations Manual in a 3-ring binder labelled, "DataStreme Atmosphere Study Guide", at the beginning of the DataStreme Atmosphere course. ***
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 investigation, you should be able to:
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 70-degree isotherm has been drawn and labeled. Complete the 60-degree isotherm shown. Also, draw the 50- and 40-degree isotherms. Write the appropriate values at both ends of each isotherm.
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.
The accompanying DataStreme Atmosphere surface Temperature map shows temperatures for a particular time on 20 February 2003. The 50 Fahrenheit-degree isotherm has already been drawn, and two local 40-degree isotherms have been done. Complete the analysis by drawing another 40-degree isotherm across the map from the East Coast to western Canada. Then do the 30-, 20-, and 10-degree isotherms in the northern US and Canada. Finally draw the 60- and 70-degree isotherms in the southern US to complete the temperature analysis.
On this map the temperature pattern is dominated by relatively low temperatures in the [(Great Lake states and Canada) (southwestern US and Gulf Coast states)] and higher temperatures in the [(Great Lake states and Canada) (southwestern US and Gulf Coast states)].
*** The following portion of the Investigation would be delivered to each participant via the DataStreme Atmosphere website by clicking on the appropriate Current Weather Studies button under Learning Files on the day it is available. Also highlighted would be meteorological products to be accessed that accompany the Current Weather Studies activity. ***
WELCOME BACK: Procedure continued from Investigations Manual.
The Image 1 map is a plot of surface Temperatures for 18Z 30 NOV 2007. The highest reported temperature on the map is ____ degrees F. The lowest is ____ degrees F.
Using a 10-F degree interval, complete the listing of isotherms that would appear at least once on this map: 10, ___, ___, ___, ___, ____, ____, ____, ____, _____.
Draw these isotherms on this map to determine the temperature pattern that existed at the time observations were made. A comparison of this November Temperatures map with that in the first part of the investigation suggests the isotherm patterns might be similar. Therefore, let us start by drawing the 10-degree isotherm in an arc about the lowest temperature in central Canada. Label it with its value at both ends. Then work southward with the 0-degree isotherm. Continue adding isotherms in the above series by drawing them from the beginning at one edge of the map where they occur or between appropriate numbers, across the interior to the other side of the map reaching the edge. Be sure to label each isotherm line at its ends.
Image 2 is the surface data plot (Isotherms, Fronts, & Data) for 18Z 30 NOV 2007, the same time as the Temperatures map you just analyzed. 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 40-degree isotherm, for example, [(does) (does not)] appear in the same area on both maps. The computer generated isotherms are usually [(more) (less)] curved than a hand-drawn analysis.
The map shows that generally surface air temperatures [(increase ) (decrease)] with an increase in latitude.
Locate regions on the map where isotherms are relatively close together as in the band from the Texas panhandle to Great Lakes area. These are regions where temperature changes are relatively [(large) (small)] along a distance perpendicular to the isotherms. This area is probably associated with [(the high pressure center) (the frontal system)].
As noted by the wind directions along and northwest of the cold front from Texas to Wisconsin, the cold air is moving generally towards the [(south and east) (north and west)]. The triangle symbols are on the [(northwest) (southeast)] side of the front to indicate the cold air is moving southeast. Stationary fronts are shown in the Atlantic, from Nevada to New Mexico and from Washington state to Montana. The semicircle and triangle symbols are attached to [(the same) (opposite)] sides of the front lines.
The 30- and 40-degree isotherms from the Texas panhandle to Great Lakes area are generally [( parallel) (perpendicular)] to the cold front.
Hold this activity until you have completed all applications for this week. Instructions for faxing your LIT mentor will appear at the end of this week's Activity.
This page was last updated 28 April 2008
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