Oceanography The Official Magazine of
The Oceanography Society
Volume 29 Issue 03

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Volume 29, No. 3
Pages 9 - 13

COMMENTARY • True Colors of Oceanography: Guidelines for Effective and Accurate Colormap Selection

Kristen M. Thyng Chad A. Greene Robert D. Hetland Heather M. Zimmerle Steven F. DiMarco
First Paragraph

Data graphics shape the way science is communicated, and the color schemes we employ can either faithfully represent or tacitly obscure the data a figure is intended to convey (Tufte, 1983). Tasteful use of color can make data graphics visually appealing and can draw viewers in, engaging the audience and encouraging further inspection of a figure. But wherever color is used to represent numerical values, its role transitions from a mere aesthetic nicety to carrying the responsibility of conveying data honestly and accurately. Yet, biases introduced by some common colormaps have gone widely unrecognized within the oceanographic community. Here, we describe the pitfalls of some commonly used colormaps, provide guidelines on effective, accurate colormap selection, and present a suite of perceptually uniform cmocean colormaps that have been designed for oceanographic data display. The cmocean package is available across multiple software programs, including MATLAB, Python, R, Generic Mapping Tools, and Ocean Data Viewer.

Citation

Thyng, K.M., C.A. Greene, R.D. Hetland, H.M. Zimmerle, and S.F. DiMarco. 2016. True colors of oceanography: Guidelines for effective and accurate colormap selection. Oceanography 29(3):9–13, https://doi.org/10.5670/oceanog.2016.66.

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