Screenshot: IOP Science
Scientists from the National Oceanic and Atmospheric Administration’s (NOAA)
Pacific Marine Environmental Laboratory and 3 scientists from the
GEOMAR Research Center for Marine Geosciences show that radiation on US
West Coast could end up being 10 times higher than in Japan.
(it's moving AWAY from Japan)
Screenshot: IOP Science
According
to the study, after 10 years the concentrations become nearly
homogeneous over the whole Pacific, with higher values in the east,
extending along the North American coast with a maximum (~1 × 10−4) off
Baja California.
Screenshot: IOP Science
With
caution given to the various idealizations (unknown actual oceanic
state during release, unknown release area, no biological effects
included), the following conclusions may be drawn.
Dilution
due to swift horizontal and vertical dispersion in the vicinity of the
energetic Kuroshio regime leads to a rapid decrease of radioactivity
levels during the first 2 years, with a decline of near-surface peak
concentrations.
The
magnitude of additional peak radioactivity should drop to values
comparable to the pre-Fukushima levels after 6–9 years (i.e. total peak
concentrations would then have declined below twice pre-Fukushima
levels).
By
then the tracer cloud will span almost the entire North Pacific, with
peak concentrations off the North American coast an order-of-magnitude
higher than in the western Pacific.
Indeed,
another team of top Chinese scientists have just published a study in
the Science China Earth Sciences journal showing that Fukushima nuclear
pollution is becoming more concentrated as it approaches the West Coast of the United States,
that the plume crosses the ocean in a nearly straight line toward North
America, and that it appears to stay together with little dispersion.
The
time scale of the nuclear pollutants reaching the west coast of America
is 3.2 years if it is estimated using the surface drifting buoys and
3.9 years if it is estimated using the nuclear pollutant particulate
tracers.
It
is worth noting that due to the current near the shore cannot be well
reconstructed by the global ocean reanalysis, some nuclear pollutant
particulate tracers may come to rest in near shore area, which may
result in additional uncertainty in the estimation of the impact
strength.
Voice of Russia, IOP Science
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