Solar Radiation Penetrating the Ocean. A Review of Requirements, Data and Methods of Measurement, with Particular Reference to Photosynthetic Productivity

Abstract

The review begins with a definition of the various terms used in measuring solar radiation the "langley" is the unit chosen as most suitable and is defined as one 15[degree] gram-calorie of energy/cm2. The amount of radiation from a source is expressed in langleys/minute, and factors are given for conversion from other units into langleys. A review of the photosynthetic requirements of marine algae mainly forms the 2d section of the paper. The distribution of radiant energy is discussed under the headings: energy at the ocean surface, losses at and in the ocean surface, absorption and scattering within the ocean, and calculations involving vertical extinction coefficients. The paper concludes with a review of methods of measuring radiation. In this section the topics covered are: surface illumination and radiant energy, submarine light and vertical extinction coefficients, transparency and scattering measurements, and use of the Secchi disc.