Purpose of Activity
This activity demonstrates optical properties of water: that different constituents in water affect the transmission, absorption, and scattering of different colors in the visible light spectrum. Inexpensive, off-the-shelf components are used to build a light sensor and source, creating a simple spectrophotometer that can measure light absorption. In the second part of this activity, principles of ocean color remote sensing are applied to measure reflectance. Using components that are clearly visible allows students to configure them in different ways. Playing with the instrument design gives students a practical understanding of spectrophotometers, in-water optics, and remote sensing. As an extension of this concept, students are encouraged to think about how ocean color is used to estimate the concentration of chlorophyll to infer phytoplankton abundance, colored dissolved organic matter, and suspended sediments.

Schollaert Uz, S. 2016. Building intuition for in-water optics and ocean color remote sensing: Spectrophotometer activity with littleBits™. Oceanography 29(1):98–103, https://doi.org/10.5670/oceanog.2016.01.

» Data Tables 1–4 and Graphs 1–2
   126 KB pdf | 175 KB Word doc

» Examples of how data tables and graphs might look
   171 KB pdf

Mobley, C.D. 1994. Light and Water: Radiative Transfer in Natural Waters. Academic Press, San Diego, 592 pp.

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