1. Light in the sea (20 points)

(a) (5 points) Assuming the attenuation of light in the ocean is approximated as an exponential function (see Section 3.8.1 in the textbook), observations indicate that the attenuation coefficient (K) in the Louisiana-Texas shelf is about 0.22 m-1 . If the mixed layer depth is 15 m, what is the percentage of solar radiation at the surface that penetrates below the mixed layer?

(b) (5 points) Using the above attenuation coefficient, calculate the approximate euphotic zone depth in the Louisiana-Texas shelf? The euphotic zone depth is defined as the depth where 1 % of light remains.