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A 29-year Citizen Science Measurement Effort


Goddard oceanographer Lachlan McKinna speaks with Bernie Fowler, a retired state senator and creator of the "Sneaker Depth" measurement.
Credit: NASA GSFC. Download this image (JPG, 6.7 MB).
[11-Jun-17] Goddard oceanographer Lachlan McKinna speaks with Bernie Fowler, a retired state senator, creator of the "Sneaker Depth" measurement.

Fowler walks into Maryland’s Patuxent River every June to see how deep he can go and still see the tops of his shoes. Now in his nineties, he ventures into the river to assess the water clarity. Fowler has been collecting this data point for the past 29 years and counting, calling it “sneaker depth.”

Now NASA is adopting Fowler’s sneaker idea to communicate satellite measurements of water clarity, enabling the observations to be shared easily with the general public, local governments or anyone who is interested. NASA scientists call this algorithm the “Fowler’s Sneaker Depth” — the depth of water, in meters, at which a person can no longer see their white shoes. The study was published in the April 2017 edition of The Optical Society journal Optics Express.

For more information on this year's event and on the "Sneaker Depth" algorithm, click here.