Each year tens of thousands of cargo containers fall overboard around the world while on ocean-going vessels. These articles are especially interesting to scientists who are studying the trade routes that link North America and eastern Asia and, especially,  the Pacific Subarctic Gyre (PSG), a ocean vortex that is about the size of the United States.

In one case, about 29,000 plastic bath toys fell overboard in the middle of the PSG in 1992. They were tracked about 4,000 kilometers (2,400 miles) to southeastern Alaska. Now, over 100 years of data has been collected from such floating objects to provide a map of the gyre’s major sub-currents and swirls.

In addition, between 1997 and 2001, Japanese science organizations sponsored the SAGE (Sub-Arctic Gyre Experiment in the North Pacific Ocean) Project to learn more about PSG.

Today, scientists know that one circuit around the PSG takes about three years. From this and other data, scientists are now able to identify long-term patterns in water temperature, salinity, and other characteristics that were unknown before.

Recently, scientists are going high-tech and deploying their own specially made probes that are monitored by satellites overhead. These probes are called Argo floats, and over 2,700 of them have been deployed over the past seven years. They are designed to remain submerged at a depth of about two kilometers, and then surface every ten days or so in order to measure various characteristics of the ocean at their present locations.

Unfortunately, probes that remain on the surface have had little success due to becoming tangled with algae, barnacles, other living organisms, and various artificially made debris found on the surface. In addition, both surface and sub-surface probes lack the power (from batteries) to remain in operation for very long, which restricts their usefulness.

So, researchers use modern-day Argo floats and primitive objects (such as tennis shoes and beer bottles) that contain identifying codes to track currents and other variables in the oceans. All of this information goes into the flotsam-recovery database that ocean researchers Curtis Ebbesmeyer and fellow-colleagues maintain.

In 2005, a Japanese donor provided $100,000 for a research project that included about one thousand wooden tops trackable with a satellite. The two-year project started when the tops were released off the western shore of Yonaguni Island (a southwestern island in Japan), about 125 kilometers (75 miles) from the east coast of Taiwan at the end of the Ryukyu Island chain. Some of the tops have already been recovered around Japan, but none of them have yet made the journey to North America.

However, if they do make it to American shores, Ebbesmeyer’s name, home address, and e-mail address is stamped on each top. So, be sure to help the project and report to Ebbesmeyer if you find one of them.

Curtis C. Ebbesmeyer can be contacted at This e-mail address is being protected from spam bots, you need JavaScript enabled to view it or at Curtis Ebbesmeyer, Beachcombers Alert, 6306 21st Avenue, NE, Seattle, WA 98115.

Additional information about the release of these wooden tops off Japan in 2005 and 2006 can be found at http://www.gondo.com/g-files/koma/page_1.htm.

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