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Images: Lessons from the 2011 Japan Quake

WHOI marine chemist Ken Buesseler pays his respects in front of Namiwake Jinja. The shrine marked  safe ground after the Jogan tsunami of 869 A.D. (Namiwake roughly translates as “split wave.”) It is a reminder that Japan has a history of devastaing tsunamis that needs to be considered when deciding how to protect the coast. (Ken Kostel, Woods Hole Oceanographic Institution)

An international scientific team led by WHOI marine chemist Ken Buesseler completed a research cruises in June 2011 to assess the level and dispersion of radioactive substances from the Fukushima nuclear power plant and their potential impact on marine life. This map shows the sampling stations and cruise track near the Kuroshio Current (shown in yellow and red). Sampling began 400 miles offshore and passed within 20 miles of the nuclear complex. (Steven Jayne, Woods Hole Oceanographic Institution)

During a two-week research cruise in June 2011, scientists collected more than 1,500 samples of seawater off the coast of Japan. They amassed more than 3 metric tons of water that was shipped to labs around the world to be analyzed for radioactive isotopes. Scientists Ken Buesseler and Steven Jayne from WHOI and Taylor Broek from UC Santa Cruz (top to bottom) take samples from a Niskin bottle, an instrument used to collect water from below the surface. (Photo by Ken Kostel, Woods Hole Oceanographic Institution)

Meanwhile, biologists used an assortment of nets to collect samples ranging from plankton to shrimp to fish to learn if radionuclides from Fukushima were accumulating in marine life. Above, biologists (left to right) Hiroomi Miyamoto, Jennifer George, and Hannes Baumann haul in a Methot net, a 2-meter-by-2-meter frame with a long, pyramid-shaped net towed at a depth of 200 meters. (Photo by Ken Kostel, Woods Hole Oceanographic Institution)

WHOI researcher Steve Pike packs water collected in the Pacific east of Japan. Water and biological samples were sent to 16 labs in seven countries to detect levels of a variety of radioactive isotopes, including strontium-90, plutonium-239, and neptunium-237. (Photo by Ken Kostel, Woods Hole Oceanographic Institution)

A tiny hatchet fish was among the variety of marine life captured during more than 100 net tows. (Photo by Ken Kostel, Woods Hole Oceanographic Institution)

Levels of radioactive cesium-137 in the ocean from nuclear weapons testing in the 1950s and '60s has gradually decreased as the radionuclide (which has a half-life of 30 years) has decayed. The Chernobyl a spike of cesium-137 in 1986. Measurements from a June 2011 cruise that came within 20 miles of the reactors at Fukushima found levels of cesium-137 approaching but not exceeding 10,000 petaBecquerels per cubic meter, which is the threshold considered safe for drinking water by the the U.S. Environmental Protection Agency. (Ken Buesseler, Woods Hole Oceanographic Institution)

WHOI physical oceanographer Steven Jayne released two dozen surface drifters into the ocean during the cruise. The drifters transmitted their locations back to shore while they moved with ocean currents. Combined with data from radionuclides, color-coded track lines from individual drifters indicated that the powerful Kuroshio Current acted as both a highway and a barrier, carrying much of the radiation quickly away from shore while also largely preventing it from spreading south. At the same time, Jayne’s drifters revealed the existence of a swirling eddy near the coast south of Fukushima that trapped radiation within it. For years to come, measurements of radionuclides released from Fukushima will help oceanographers like Jayne trace currents and mixing throughout the Pacific Ocean. (Steven Jayne, Woods Hole Oceanographic Institution)

Human and natural sources of radioactive isotopes in the ocean. NOTE: colored ovals not drawn to scale. (Illustration by Jack Cook, courtesy of the Coastal Ocean Institute, Woods Hole Oceanographic Institution)