Fukushima ocean radiation could pose sleeper threat

[flamingdem]

excerpt:

Scientists have determined that the unprecedented release of radioactivity into the Pacific Ocean from the Fukushima nuclear disaster poses no direct exposure threat to people, but caution that the accumulated fallout lying in sediment is a potential danger for decades to come.

The findings were published in a report, Impacts of the Fukushima Nuclear Power Plants on Marine Radioactivity, on Wednesday. Levels of cesium and iodine peaked in April, a month after the core meltdowns when seawater used to cool the reactors and spent fuel rods was pumped out of the facility into the nearby ocean.

Levels of radioactive cesium peaked at 50 million times normal levels, becoming the largest accidental release of radiation into the ocean in history, said Woods Hole Oceanographic Institution chemist Ken Buesseler.

Buesseler and two Japanese colleagues, Michio Aoyama of the Meteorological Research Institute and Masao Fukasawa of the Japan Agency for Marine-Earth Science and Technology, collaborated on the report. The Gordon and Betty Moore Foundation and the National Science Foundation’s Chemical Oceanography program funded the research.

The concentrations of cesium offshore were much higher than those measured in the ocean after the Chernobyl accident 25 years ago, Buesseler added. However, unlike Chernobyl, the ocean mixing processes “rapidly diluted” radiation off the Northwest coast of Japan.

The fallout decreased by a factor of 1000 by May as the ocean and the “radionuclide source that has dramatically abated,” diluted the fallout, Woods Hole noted in a press release. Still, radiation remained 10,000 times higher than baseline levels measured a year before the disaster through July.

http://www.smartplanet.com/blog/intelligent-energy/fukushima-ocean-radiation-could-pose-sleeper-threat/11042

[Karenina]

1. Ya thimk??? Naaaah...

:crazy:

[jpak]

2. do pro-nucular science types know what that device is in the photo?

:shrug:

:rofl:

[FBaggins]

3. I think the formal name is "A-BOPP"

As in "A bunch 'o PVC pipe"

It's presumably a rig that allows them to close simple chambers either remotely or on a set schedule so that they can sample seawater from multiple depths and/or locations without stopping for each reading.

Something like a jury-rigged rosette.

[jpak]

4. Nope

try again

[FBaggins]

5. No really. That's what it is.

He's out sampling water from multiple locations in the ocean. A rosette is the common tool for doing so. That one looks like it was put together by a kid and seen better days... but what else would it be? This isn't exactly rocket science.

[jpak]

7. Close - it's a CTD rosette

n/t

[FBaggins]

8. Sorry... no. A rosette doesn't have to have a CTD. Can you point to it?

Otherwise... why are you assuming it's there?

On edit - WHOI simply calls it a "water-sampling rosette".

http://www.whoi.edu/page.do?pid=7545&tid=441&cid=191893&ct=61&article=123049
http://www.whoi.edu/page.do?pid=7545&tid=282&cid=103069&ct=162

[jpak]

9. The instruments are behind the Niskin bottles

The things you call PVC pipes

:D

[FBaggins]

10. And what are you basing that on?

The people using it don't label it as such and no such device is visible.

Seems your picking at non-existent nits again. :)

The things you call PVC pipes

Since we're picking nits... what did you think niskin bottles are made of?

[jpak]

12. My personal experience conducting thousands of CTD casts

yup

[FBaggins]

13. And you've never seen or heard of a rosette without a CTD?

I find that hard to believe.

Have you gotten in touch with Woods Hole to let them know that they don't know what to call their device?

[jpak]

14. No - that would be stupid - how would you know where they were tripped?

not by the amount of cable played out - that's for sure

:rofl:

[FBaggins]

15. The CTD is not the only device that can tell you the depth you're at.

Once again... have you told WHOI that they don't know their own equipment?

They do have rosette's with CTDs and use them where appropriate. They also label them as such when talking about them... in this case they clearly called it just a "water sampling rosette".

"The PI must specify during the cruise planning process whether a CTD/rosette system is required. If a CTD is not specified, it will be assumed not to be needed, and may be removed for calibration or maintenance."

[jpak]

16. A rosette without a CTD package is useless - and you cannot do depth profile sampling

without a CTD

sorry

:D

[FBaggins]

17. Sorry. That's flat wrong.

As I've demonstrated, rosettes are used all the time without a CTD. It depends entirely on what you're looking to study. They could be set up in an auto-fire mode or be controlled from the deck.

I won't doubt your claim that you've used one before... but you obviously don't have experience with all of the ways that they're used.

And btw - re: your #14... yes, you absolutely can estimate depth pretty accurately by the amount of cable you've paid out (combined with speed/current/etc). Not that there appears to have been a need for such in this case.

[flamingdem]

6. So what is dat ting? nt

[jpak]

11. A CTD rosette - the white tubes are Niskin bottles (you can see the caps cocked at the top)

The electrical cable running down the hydro-wire connects to a package of instruments that measure Conductivity (salinity) Temperature and Depth (hydrostatic pressure) - as well as oxygen sensors, flourometers (measures chlorophyll) and transmissometers (measure turbidity).

The Niskin bottles have caps attached to elastic bands or springs - the whole shebang is lowered through the water column and give a real-time picture of the water column.

The scientists look at the depth profile and trip the Niskin bottles at the depths they want. The bottles collect water at those depths and are brought to the surface for analysis.

and...I seriously doubt Ken is using this one for iron measurements - lol