1) An El-Nino occurred during the years of 1982-1983 and 1991-1992; a La-Nina occurred during 1988-1989.  Based upon the information in the tables, what happens to the precipitation amounts in the cities of Minneapolis, Los Angeles, and New Orleans during these times?
 
 
 
 
 

2) Find the (approximate) average daily temperature for the three cities between the given months.  Have students calculate this by adding the average daily temperatures for November through March, then dividing the sum by 5.
 

	Minneapolis	Los Angeles	New Orleans
Winter 1982-83 (Nov.-Mar.)	25.26o Fahrenheit	58.3o Fahrenheit	57.72o Fahrenheit
Winter 1982-83 (Nov.-Mar.)	19.51o Fahrenheit	57.12o Fahrenheit	60.29o Fahrenheit
Winter 1982-83 (Nov.-Mar.)	23.29o Fahrenheit	60.07o Fahrenheit	56.67o Fahrenheit

3) Find the normal average daily temperature for each of the three cities during the months of November through March.
 
 

Minneapolis: 22.36o Fahrenheit

Los Angeles: 58.18o Fahrenheit

New Orleans: 56.56o Fahrenheit

 

4) Based upon the above information, how does an El-Nino and/or a La-Nina affect average daily temperatures in the three cities?

In Minneapolis, an El-Nino leads to warmer than average temperatures; a La-Nina to lower than average temperatures.  In Los Angeles the same holds true, but it is not as pronounced as in Minneapolis.  In New Orleans, the temperatures during all three winters is warmer than normal, with the La-Nina winter the warmest.

5) Find the (approximate) average daily temperature (in degrees Fahrenheit) for the three cities between the given months:
 
 

-	Minneapolis	Los Angeles	New Orleans
Summer 1983 (May-Sept.)	65.26o Fahrenheit	68.71o Fahrenheit	77.89o Fahrenheit
Summer 1988 (May-Sept.)	68.26o Fahrenheit	66.32o Fahrenheit	78.74o Fahrenheit
Summer 1992 (May-Sept.)	61.24o Fahrenheit	69.40o Fahrenheit	78.03o Fahrenheit

 
6) Find the normal average daily temperature for each of the three cities during the months May through September.
 
 

Minneapolis: 66.26o Fahrenheit

Los Angeles: 67.58 Fahrenheit

New Orleans: 79.26 Fahrenheit

 

7) Based on the above information, how does an El-Nino and/or a La-Nina affect average daily temperatures during these months in the three cities?
 
In Minneapolis, an El-Nino seems to make the average daily temperature cooler, while a La-Nina makes the average daily temperature warmer.  The opposite holds true for Los Angeles: A El-Nino seems to make for warmer than average temperatures, while a La-Nina seems to make for cooler than average temperatures.  For New Orleans, the average temperature during all three events was lower than the normal average.

Extension Exercises:

1) On a separate sheet of paper (or on the computer), create a line graph.  The horizontal axis of the graph should represent the months of the year, the vertical axis should represent the average daily temperature in degrees Fahrenheit.  Choose one city: either Minneapolis, Los Angeles, or New Orleans.  Graph either the average daily temperature amounts for each month in problem #2 (November through March) or #5 (May through September).  Also graph the normal average daily temperatures for each month.  There should be four lines on each graph.

2) Check to see how the average daily temperatures in each of these cities fared during another El-Nino or La-Nina.  Your teacher has the web site addresses for the years of other El-Nino and La-Nina occurrences.  See if your answers to problems #4 and #7 hold true during other El-Nino and/or La-Nina occurrences.

3) Check to see how the average daily temperatures in other cities fared during an El-Nino or a La-Nina.  The links on the bottom of the Monthly Temperature and Precipitation Totals page contains this information for several weather stations across the United States.