AEROGRAPHER'S MATE 3 & 2 



SCALE (N.M.) 

 RADFO OVERLAY 



Figure 11-28. — A portion of diagram showing the area of deposition. 



209.358 



SKEW-T DIAGRAM 



The SKEW-T Diagram is the standard thermo- 

 dynamic chart in use throughout the Navy today. 

 This diagram is a graphic representation of pres- 

 sure, density, temperature, and moisture, in 

 a manner that the basic atmospheric energy 

 transformations are visually depicted. A unit 

 of area on the diagram represents a specific 

 quantity of energy. This diagram when plotted 

 with the various meteorological elements, re- 

 ceived from an upper air sounding, presents 

 a vertical picture of the atmospheric conditions 

 present at the time of observation and allows 

 for computations of various parameters required 

 by forecasters. 



DIAGRAM DESCRIPTION 



The standard SKEW-T Diagram for general 

 use is a large multi-colored (brown, green, 

 and black) chart with numerous scales and graphs 

 superimposed upon each other. (See figure 11-29.) 



The five basic lines on the chart are as fol- 

 lows: 



1. ISOBARS-Horizontal, solid, brown lines, 

 spaced logarithmically for 10-mb intervals. Pres- 

 sure-value labels are printed at both ends and 

 in the center of isobars for each 50-mb in- 

 terval. The upper portion of the chart from 

 400 to 100 mb is also used for pressure values 

 from 100-25 mb. Labels for the latter range 

 are printed in brackets at the ends of the ap- 

 propriate isobars. (See figure 11-30.) 



2. ISOTHERMS-These are the straight, solid, 

 brown lines, sloping from the lower left to 

 the upper right, with the spacing equal through- 

 out the diagram. They are labeled for 5°C 

 intervals, with alternate 10°C temperature bands 

 tinted green. \. Fahrenheit temperature scale 

 is printed along the bottom edge of the chart 

 to coincide with the appropriate isotherms. (See 

 figure 11-31.) 



3. DRY ADIABATS-The slightly curved, solid 

 brown lines, that slope from the lower right 



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