V. TEN-DAY COMPOSITE TEMPERATURE CHARTS 



Ten-day composite charts should be siifficient for determination of 

 general temperatiire patterns in areas where the axes of currents are 

 fairly constant. In practice, 10-day composite charts are dravn every 

 5 days on an overlapping basis. This procedure allows for a relatively 

 large number of reports over small time intervals. 



Daily sea svirface temperatvire charts utilize the latest composite 

 chart or daily pattern as a guide. The prime object of composite charts 

 is provision of means for achieving continuity between successive iso- 

 therm patterns. In order to consejrve space and provide visual data con- 

 trol, the following symbols and color code are used on composite charts. 



Day 



1st throiigh 5th 



6th 



7th 



8th ..... , 

 9th ..... , 

 10th 



Examples: 



Ten-Day Composite Chart Data Code 

 Symbol Color 



• Purple o . 



Light Blue 

 ^ Green 



y Black 



+ Red . 



X Pu3rple 



Blue . 



Green 



Temp, (o F) 

 <30 

 30 - 39 

 i+0 - 1^9 

 50-59 

 60-69 

 70 - 79 

 80 - 89 

 >90 



55.^° F for the Uth day is coded as •5.i^ in black 

 7**° F for the 7th day is coded as A** in purple 



Date indicators serve to show daily variations of water temperatures; ' 

 the color code minimizes data congestion, aids in scanning large quantities 

 of data, and helps to screen out gross data errors. The last 5 days of 

 data on a 10-day ccanposite chart are carried forward to the next composite 

 chart using dot symbols; the remaining 5 days of data, accumulated from 

 daily charts, are added by using individual symbols as shown in the preced- 

 ing table. (The last 5 days of data on an 11-20 August composite chart 

 would be transferred to a 16-25 August chart using dot symbols, the re- 

 maining days would carry individxaal symbols.) 



Portions of two composite charts for 26 July-5 August and l6-25 August 

 1961 are shown in Figures 10 and 11. General agreement of tbe patterns in 

 these charts suggests that oceanic current systems are more stable than 



12 



