120" E. 130° 



140° 150° 160° 170° 180° 170° 



160° 150° 



130° 120° 110° W 100° 



METEOROLOGICAL 

 STUDY REGION 



TWZO REGION 



^M^ "^^^ ^N R t H PACIFIC "\ \ 



y0^y: EQUATORIAL WATER j) 



I 10° 



120° E 130° 140° 150° 160° 170° 180° 170° 



150° 140° 130° 120° 



1 10° W. 100° 



Figure 1. — The oceanographic and meteorological observational regions for the Trade Wind Zone 



Oceanography Pilot Study. 



temperature, the difference between the satura- 

 tion vapor pressure of water and air vapor pres- 

 sure, the vapor pressure of the air, the cloud 

 cover, the sea level atmospheric pressure, the 

 wind speed, and the zonal and meridional com- 

 ponents of the wind velocity. Table B contains 

 interpolated values for the center of each 5° 

 square of the sea-water temperature, the air 

 temperature, the vapor pressure of the air, the 

 cloud cover, and the wind speed. Tabulated 

 alongside these meteorological properties are 

 the derived heat exchange processes: the radia- 

 tion from sun and sky, the back radiation, the 

 heat of evaporation, the conduction of sensible 

 heat, and the net heat exchange across the sea 

 surface. Interpolated meteorological proper- 

 ties and their derived heat exchange processes 

 are presented in geographic format to facilitate 

 contouring. 



The magnetic tape containing the data that 

 were used for the summaries and for the de- 

 rived heat exchange processes computed for 

 each weather record is kept on file to permit a 

 more detailed analysis than is presented here. 



The sources of data, the methods of process- 

 ing, and the computation of heat exchange proc- 



esses, as well as an evaluation of the results, 

 are presented below. 



SOURCES OF DATA 



About 80,000 sets of meteorological observa- 

 tions were used in the preparation of this report. 

 Their principal source was the surface marine 

 observations Card Deck No. 128 of the National 

 Weather Records Center. To those data were 

 added the meteorological observations recorded 

 onboard the BCF (Bureau of Commercial Fish- 

 eries) research vessels Townsend Cromwell and 

 Charles H. Gilbert which were not already a 

 part of the surface marine deck. 



Meteorological data in latitudes of the central 

 North Pacific south of Hawaii are scarce. It is 

 therefore valuable to add to the surface marine 

 observations those made on Johnston Island (lat. 

 16°45' N., long. 169°30' W.) and on Christmas 

 Island (lat. 1°51' N., long. 157°23' W.). Because 

 both islands are atolls, the early morning mete- 

 orological conditions would approximate those 

 over the adjacent ocean. 



Johnston Island sea level observations were 

 obtained from the National Weather Records 



