In 1968 and 1969 I participated in airborne measurements of ocean 

 color at V/oods Hole, as reoorted herevvith by Clarke, Ewina and Lorenzen 

 (Spectral Measurements from Aircraft of Backscattered Light from the Sea 

 in Relation to Chloroohyll Concentration as a Possible Index of 

 Productivity. George L. Clarke, Gifford C. Ewing and Carl J. Lorenzen, 

 SCIENCE, p. k, in press.) 



In correspondence with C. F.Hagelberg, 8 July I969, I set forth 

 "calculations [which] relate the visible spectrum of the total upwelling 



light from the ocean waters to the chlorophyll content of the water 



These calculations, which produce results that correlate well with measure- 

 ments with the water color spectrometer, indicate that the use of a 

 minimum of only two bands should result in a chlorophyll determination." 



18-2 



