KPBS, Feb. 13, 2014 (at 3:30 in) — Q: There have been a number of reports of the so-called ‘Fukushima plume’ — is this the radioactivity that you’re hoping to track or monitor with this project? Matt Edwards, San Diego State University: It’s definitely linked to that, yeah. When we talk about a plume of water, we’re really talking about is a consolidated mass of water that’s moving in unison. That’s happening here. But also, when you’re dealing with currents, and water, and motion of the ocean, things just dissipate, they basically become more dilute — more dilute as they spread out. If you think about putting cream in your coffee and you just put a little bit of motion to your coffee, the cream doesn’t stay there in nice striated patterns, it really becomes kind of uniformly dissolved throughout — the same thing kind of happens in the ocean.
Predicting the spread of nuclear radiation from the damaged Fukushima Nuclear Power Plant (pdf), State Oceanic Administration of China, published May 12, 2011 (emphasis added): […] The ocean circulation model indicates that the nuclear material would be slowly transported northeast of Fukushima and reach 150°E in 50 days, and the nuclear debris in the ocean would be confined to a narrow band. […] The nuclear debris would be transported northward by the ocean currents initially, approach 38.5°N, and turn eastward 20 days later. […] The nuclear debris in the ocean would be confined to a narrow band.
What happens to this “narrow band” of confined nuclear material as it approaches West Coast?
Topics in Ocean Physics, 1982 (emphasis added): The drifter data [see map] show that the mesoscale produces very little dispersion in the eastern Pacific beyond a 300 km scale. This is in sharp contrast to drifter and hydrographic data from the western Pacific and Atlantic basins. The drifter data do not support the concept of large-scale turbulent motion and random dispersion of clusters of parcels [...] it seems that the drifters tend to find and follow the strongest currents.
Recall Prof. Edwards’ assertion — radioactive materials “become more dilute as they spread out [it] doesn’t stay there in nice striated patterns, it really becomes kind of uniformly dissolved.”
Yet the studies above concluded: 1) Nuclear material from Fukushima is “confined to a narrow band” as it crosses the Pacific to North America; and 2) As it approaches West Coast, there’s “very little dispersion in the eastern Pacific.” See also:
- US Gov't Memo: Nuclear fall-out in ocean does NOT gradually spread out -- 'Streams of higher radioactive materials'
- Congressional Researchers: Potential for corridor of “highly contaminated” water traveling across Pacific from Fukushima
Published: February 14th, 2014 at 11:03 pm ET