An Oceanographic Illuminometer for Light Penetration and Reflection Studies

摘要

An improved illuminometer system is described which consists of a dual underwater illuminometer and a deck illuminometer both having improved light collecting properties and a new deck measurement unit. The instrument can provide direct measurements of (1) the illumination on the ocean surface, (2) the ratio of the downwelling illumination in the ocean to that on the ocean surface, (3) the ratio of the upwelling to the downwelling illumination in the ocean, (4) diffuse attenuation coefficient, K, for the downwelling light field, and (5) the depth of the underwater sensor. Emphasis in the design of the equipment has been to provide a system with which the operator can quickly obtain direct, accurate settings and to minimize the opportunity for human error in reading the results. The design philosophy of the lambertian light collector and the photoelectric circuitry is given along with the resulting performance. Examples of the data obtained with this system and its applications are given. (Author)