

Above, inverted painted bulb-type unit, and 

 below, the shielded-type unit, both measur- 

 ing one half the total radiation reflected from 

 the ocean surface. The boom is extended 

 while underway. 



The unit in process of measuring total 

 incoming solar radiation. 



Securing the booms and installing protective covers 

 as a safety precaution when not in use. 



The pyrheliometer is used for measuring solar radiation by its thermal effects. The instrument used m this 

 installation is a 180° thermoelectric pyrheliometer. The strip chart recorder used to record the data is a 

 self-balancing potentiometer especially designed for solar radiation work and reads directly in radiation units. 

 The installation is designed for the collection of data that will increase knowledge of the heat budget of the 

 oceans. The specific data problems involved are (1) the measurement of total incoming solar radiation and 

 (2) measurement of total reflected radiation from the water surface and relating this to varying sea surface 

 conditions. One pyrheliometer is used to record total incoming solar radiation ; two instruments are installed 

 on booms and suspended in an inverted position over the sea surface, each picking up radiation from one half 

 the sea surface. 



H. O. 607 



Figure 11-1. Shipboard arrangement of pyrheliometer colLs 



113 



