The warming of the ocean surely has an impact on changing growth patterns of marine plants and animals, just as the changing pH or acidity of the ocean has been shown to modify habitat and migrations. But what else?
he effect of radiation leaking from the three nuclear power plant reactors shut down by the earthquake and resultant tsunami tidal wave that inundated Fukushima, Japan in 2011, and has been thereafter distributed by ocean currents; indeed there is evidence of a plume of increased concentration of Cesium-134, and other radioactive elements that have been observed at unprecedented levels, spreading out some 5,000 miles into the Pacific toward North and South America. In April of this year, there were headlines declaring that “Fukushima radiation has reached the North American Shore” and concerns were raised, spread through the Internet and press, that this was surely the cause of these otherwise inexplicable anomalous natural events.
There is no Federal agency that funds monitoring of radiation in coastal water, and the present effort, conducted since 2004 by Ken Buesseler, a marine chemist at the Woods Hole Oceanographic Institution, has been underwritten by crowd-funding and the efforts of volunteers taking samples to provide data on cesium isotopes along the west coast of Alaska, the U.S. mainland coast, and Hawaii, the information that has been used to model potential distribution and concentration of any contamination. A comparable effort has been launched in Canada, led by Jay Cullen of the University of Victoria in collaboration with government, academic, and NGO partners.
Scientists continue to study the effects of radioactive contaminants on the marine environment following the earthquake, tsunamis, and resulting radiation leads from the Fukushima Dai-ichi nuclear power plant in Japan. On March 11, 2011, a 9.0 magnitude earthquake 80 miles off the Northeast Coast of Japan triggered a series of tsunamis that struck nearby shorelines with only a few minutes’ warning. The disaster left dozens of villages along nearly 200 miles of coast heavily damaged or completely destroyed.
The waves, some of which measured more than 40 feet, also struck the Fukushima Dai-ichi nuclear power plant 150 miles north of Tokyo, disabling the plant’s emergency systems and causing emergency crews to use seawater to cool the damaged reactors. Because of the plant’s location along the coast, much of the water washed into the Pacific, resulting in the largest accidental release of radiation to the ocean in history. Additional airborne radioactive material from the explosions and fires at the plant fell onto the sea surface, where it too mixed into the water, as did subsequent leaks from tanks on the site holding treated water.
Within months of the accident, Ken Buesseler, a senior scientist at the Woods Hole Oceanographic Institution (WHOI), assembled a research cruise and science party of 17 people from eight institutions to sample the waters surrounding the nuclear plant. The scientists found elevated levels of the nuclear by-product cesium but they were below the threshold of concern for direct human exposure. The levels of cesium had diminished quickly off shore because cesium is soluble in seawater and was therefore diluted by the Pacific ocean currents. They also measured cesium and other radionuclides in plankton and fish and, in subsequent cruises, collected sediments from the seafloor near the plant. To this date, important fisheries off Fukushima remain closed due to levels of cesium that are above Japanese limits for seafood.
Through the newly established Center for Marine and Environmental Radioactivity(CMER), Buesseler continues to promote public education, training in marine radiochemistry, and research and engineering related to Fukushima and other natural and human sources of radioactivity.