sail-world.com
 
 
News Home Cruising Photo Gallery Video Gallery

 

Sail-World.com : Radiation and the Oceans

Radiation and the Oceans

'Human sources of radiation released into the atmosphere over the past 60 years'    Woods Hole Oceanographic Institution (WHOI) ©

On March 11, 2011 a magnitude 9.0 earthquake—one of the largest ever recorded, occurred 80 miles off the coast of Japan. The earthquake created a series of tsunamis, the largest estimated to be over 30-feet, that swept ashore along the northeast coast of the main island, Honshu. In addition to killing more than 9,000 people, the earthquake and tsunamis badly damaged the Fukushima Daiichi nuclear power plant, eventually causing four of the six reactors there to release radiation into the atmosphere and ocean.

What is being released from the Fukushima reactors and how dangerous is it?
So far, we know that releases from the Fukushima reactors have been primarily composed of two radioactive substances: iodine-131 and cesium-137. In large doses, both of these isotopes or radionuclides, as they are called, can cause long-term health problems. So far, however, only those working at the plant face the most serious exposure.

More about iodine-131 and cesium-137

Are there different types of radiation?
In general, there are two types of radiation, ionizing and non-ionizing. Non-ionizing radiation includes visible light and radio waves—things that, as the name implies, do not have the ability to form charged ions in other materials. Ionizing radiation, however, can and as a result presents a serious health threat because it can alter the atomic structure of living tissue. Ionizing radiation also comes in several different types, including alpha, beta, and gamma radiation, all with different degrees of concern and health impacts.

More about types of radiation

How long is the radiation from these substances a risk to humans and the environment?
Radioactive materials are, by their very nature, unstable and decline in strength over time. This change is measured in half-lives—the length of time it takes for the radiation to decrease by one-half. Every radioactive substance has a different half-life, ranging from fractions of a second to billions of years. Those with longer half-lives are potentially more difficult to deal with because they remain radioactive for longer periods of time. Cesium-137, for example, has a half-life of 30 years and so is a potentially serious health threat for decades or centuries. Iodine-131, on the other hand, has a half-life of just 8 days and so loses much of its potency after just days and effectively disappears after one to two months.

More about half-lives

How far can radiation travel?
Ionizing radiation itself cannot travel very far through the air. Typically, dust and other particles, seawater and other liquids, or even gases become radioactive due to exposure to radionuclides and are then transported great distances. In the months and years after the explosion at the Chernobyl nuclear power plant in Ukraine scientists were able to track the spread of radioactive material in the atmosphere and the ocean around the globe. Within a week after the explosions at the Fukushima plant, there were reports of very small increases in the continental U.S.

More about mapping and monitoring radiation from Japan

The background level of radiation in oceans and seas varies around the globe -  Woods Hole Oceanographic?nid=82256 Institution (WHOI) ©  


What is the normal background level of radiation?
The normal background level of radiation is different for different places on the planet. Radiation in some places is higher because these receive less of the natural protection offered by Earth’s atmosphere or because they are in places where the surrounding rocks contain more radioactive substances, such as radon. In the ocean, the largest source of radiation comes from naturally occurring substances such as potassium-40 and uranium-238, which are found at levels 1,000 to 10,000 times higher than any human sources of radiation (see illustration). The largest human release of radionuclides was the result of atmospheric nuclear weapons tests carried out by the U.S., French and British during the 1950s and 60s. Despite even the high concentration of nuclear fallout in the Pacific caused by U.S. tests on the Marshall Islands, there is no known adverse health effect associated with eating seafood from the Pacific.

More about natural background radiation

If there are warnings in Japan about eating certain products contaminated by radiation, why is it safe to eat the seafood?
Except for the vicinity of the reactors, seafood and other products taken from the sea should be safe for human consumption. Radiation levels in seafood should continue to be monitored, of course, but radiation in the ocean will very quickly become diluted and should not be a problem beyond the coast of Japan. The same is true of radiation carried by winds around the globe. However, crops and other vegetation near the reactor site (including grass that cows eat to produce milk) that receive fallout from the atmosphere build up radioactivity can remain contaminated even if washed. When these foods are consumed, a person receives much of this dose internally, often a more severe pathway to receive radiation than by external exposure.

More about radiation and food safety

How does radiation released from the Japanese reactors compare to the accident at Chernobyl?
We still don’t know exactly how much radiation was released at Fukushima or how much will ultimately be released before the reactors are fully contained. The Chernobyl accident was much more violent and resulted in a complete breach of the reactor vessel. The event also started a very hot graphite fire that released large amounts of radioactive material into the atmosphere equivalent to between 3 and 5 percent of the total reactor inventory. Winds carried the radioactive fallout first to the north and eventually into the Black Sea to the south. Radiation in the Black Sea and Baltic Sea, though elevated, remained well below EPA guidelines for radiation in drinking water.

More about the after-effects of Chernobyl

How will the radioactive material released in Japan affect humans?
It’s still too early to tell, but unless we learn that the type or amount of material released is larger than reported or changes dramatically it will likely have significant long-term impacts only within a few miles or tens of miles from the plant. This is because the further the radioactive material travels, the more dispersed (and the less harmful) it becomes. The effects of Chernobyl were felt well beyond Ukraine in part because the amount of radioactive material released was large and because it also included substances such as plutonium that have very long half-lives. That being said, people who live near the plants would be wise to follow the minimum safe distance restrictions and other precautions recommended by the Japanese government and at-risk individuals should take suggested extra precautions such as taking potassium iodide to avoid thyroid problems.

More about radiation in the environment

Is there any danger to people in other parts of the world?
Prevailing winds over from Japan blow east towards North America; ocean currents in the region also flow generally east into the North Pacific, though much slower than winds. However, radioactive materials carried by winds or currents will be quickly diluted until the radiation falls below background levels. Unless radioactivity from Fukushima finds its way directly to another part of the world through food or other commercial products, it should become sufficiently dispersed over time that it will not prove to be a serious health threat elsewhere. Over time, the radioactivity associated with the Fukushima plant should continue to decline even further. In particular, radiation from iodine-131 will decay very quickly, but even the effects of the much longer-lived cesium-137 will decline in strength. Today, people who eat seafood from the Black Sea, which received a considerable amount of fallout from Chernobyl (see map), consume a dose of cesium-137 that is 100 times below the one provided by a naturally occurring radionuclide, polonium-210, that is not considered harmful to animals or humans.

More about the environmental health effects of radiation

Why is this event of interest to oceanographers?
Oceanographers use substances called tracers to study the path and rate of ocean currents and of processes such as mixing that are important parts of the global ocean and climate systems. There are many different radionuclides that scientists use as 'clocks' to measure how fast the ocean mixes and sediment accumulates on the seafloor. Some of these substances are natural, but many are the result of human activity, such as the Chernobyl accident or nuclear weapons testing, and now releases at Fukushima.

More about radioactive tracers in the ocean

Woods Hole Oceanographic Institution




by Woods Hole Oceanographic Institution

  

Click on the FB Like link to post this story to your FB wall

http://www.sail-world.com/index.cfm?nid=82256

9:57 AM Sat 9 Apr 2011 GMT






Click here for printer friendly version
Click here to send us feedback or comments about this story.


News - USA and the World

Volvo Ocean Race 2014-15, Day 14 onboard Team Alvimedica. Our boat smells a bit better this morning and I’m not sure if it’s because the gnarly concoction of freeze-dried brew in the bow has been sacrificed to the sea along with some of Mark, Charlie, and Alberto’s head hair, or if it’s because those three have had a complete bathing following said sacrifice to King Neptune. ... [more]  

A remarkable list of contributors to sailing in the U.S. were presented with US Sailing’s highest honors during Friday night’s Awards Dinner, presented by Rolex, at the Hilton Milwaukee City Center. ... [more]  

Volvo Ocean Race: Heading for the speedway to Cape Town *Feature by Richard Gladwell, Sail-World.com/nz
The Volvo Ocean race fleet are now all around the turning mark of Fernando de Noronha, and have continued down the Brazilian coast. Currently the first three yachts, Abu Dhabi Ocean Racing, Team Brunel and Team Vestas Wind are all travelling at 17kts, as they travel around the St Helena High. ... [more]  

Join the crew of the ORMA60 TeamVodafoneSailing as they slash 20 minutes off their previous record for the PIC Coastal Classic on Friday. The Coastal Classic is a 119nm course from Auckland to Russell in the Bay of Islands. Originally conceived as a drag race between multihulls and monohulls ... [more]  

The 35th Rolex Middle Sea Race was one to remember. Not only for international fleet that, for the third year in a row, set a record number of entries, but for the array of conditions that the yachts faced. From no wind to too much; from flat calm to turbulent seas; from going nowhere to flying fast and furious: the 606-nm mythical racecourse offered everything. ... [more]  

Volvo Ocean Race 2014-15, Day 14 onboard Team SCA. I’m discovering there are two types of days offshore: the days where not much happens, and the days where so much happens it’s hard to believe that’s just one day! Yesterday was one of those days and I’m unsure where to begin! ... [more]  

Day four at the 2014 RS:X Youth Worlds in Clearwater, Florida, and the sound of the day was that of racers whooping and hollering past the race committee boats (two imposing 44-ft power catamarans provided by event sponsor MarineMax) in a breeze that high-wind specialists had been waiting for all week. ... [more]  

The prize giving ceremony for the Rolex Middle Sea Race was held at the Mediterranean Conference Centre, one of Valletta's most historic venues. Honoured guests included: The Minister of Tourism; The Hon Dr. Edward Zammit Lewis. ... [more]  

Dongfeng Race Team is putting in a dominant performance at the China Cup International Regatta, with scores of 1,1,1,2 so far in IRC Division B, with last year’s winner Whiskey Jack in second. The Jeanneau Sunfast 3600 is skippered by the boat’s designer, Frenchman Daniel Andrieu. ... [more]  

2014 Optimist World Championship - The first stage of the OptiWorlds Argentina 2014 schedule has finished today. The fleet was divided in three equal parts: the first third is gold, the second one is silver and the last fleet is bronze. This individual regatta continues next Tuesday. ... [more]  

2014 - 15 Volvo Ocean Race - Abu Dhabi Ocean Racing won the race to the Equator late on Thursday and were in good shape to make the turning mark of Fernando de Noronha at the head of the Volvo Ocean Race fleet as their six rivals were still playing catch-up despite finally escaping the Doldrums. ... [more]  

After more than 17 years with the International Sailing Federation (ISAF) Jerome has decided to pursue other professional challenges. ... [more]  

2014 Renaissance Re Junior Gold Cup - Stamina and determination were key factors for the competitors racing in day two of the Renaissance Re Junior Gold Cup today. The 14 international guests and 26 young Bermudians finished five races on Bermuda’s Great Sound. This is a test of endurance for any sailor especially young ones. ... [more]  

With less than a day left to reach the turning mark at Fernando de Nonoha, 220nm off the coast of Brazil, Abu Dhabi Ocean Racing has retained the lead she built in the Doldrums. She is unlikely to be headed, although the second boat on the water, Team Brunel is projected to be less than an hour behind at Fernando ... [more]  

2014 International Masters Regatta - Anyone heading out to San Diego Bay this weekend is likely to witness some of sailing’s most legendary skippers show exactly why they’ve earned the reputation as the best in the business. Established in 1975 by Don Trask, the International Masters Regatta features the best master sailors from around the world and is being hosted by the San Diego Yacht Club ... [more]  

One flight of the Quarter Finals was sailed Friday afternoon following the completion of the Qualifying Rounds and the selection of opponents and draw for boats. The Quarter Finals set Ian Williams against Marek Stanczyk, Taylor Canfield against Steffan Lindberg, Eric Monnin against Pierre Morvan, and an all Swedish pairing of Bjorn Hansen against Johnie Berntsson. ... [more]  

What could be better than racing for three days with over 2000 of the world's best sailors? How about racing for four days! The St.Maarten Heineken Regatta is proud to announce that their pre-event, the Gill Commodore's Cup, is accepting entries in all boat categories (excluding Lottery Class). ... [more]  

The seventh day of the La Torche PWA Grand Slam saw the light winds continue, despite a promising forecast for today. In the late afternoon a few of the sailors took part in a tow-in training session as there is scope to run a tow-in contest tomorrow, with the forecast looking glassy. ... [more]  

Picture postcard perfect conditions returned to Bermuda for the third and final day of Qualifying at the Argo Group Gold Cup, the sixth stage of the 2014 Alpari World Match Racing Tour. After yesterday’s torrential rain, Hamilton Harbour was bathed in glorious sunshine and breeze that by lunchtime was gusting up to the mid-teens. ... [more]  

Volvo Ocean Race: Leaders pass Fernando and head for Cape Town *Feature by Richard Gladwell/Sail-World.com/nz
Volvo Ocean Race Control reports that the lead boats in the 40,000nm race have rounded, or rather passed, the turning point off Fernando de Noronha. They are now proceeding down the Brazilian coast, to round the back of the South Atlantic high pressure zone , and have what is expected to be a fast ride to the Leg 1 finish in Cape Town. ... [more]  

Melges 32 Gold Cup on the horizon by International Melges 32 Class Association
With a fleet and sailors as diverse as the nightlife on Ocean Avenue, the Melges 32 Gold Cup, hosted by the Coconut Grove Sailing Club kicks off in just two weeks, featuring eighteen ultra-high performance Melges 32 teams from nine different countries. ... [more]  

Rolex Middle Sea Race - Keeping a good watch by Media Royal Malta Yacht Club
Peter Dimech, Principal Race Officer and Race Chair spoke about the storm that raged through the Rolex Middle Sea Race fleet. “The remaining yachts racing in the Rolex Middle Sea Race are expected to arrive at the Royal Malta Yacht Club by today and tomorrow. Whilst the wind speed has decreased, the sea state is still significant and we are keeping a close watch on the yachts still at sea. ... [more]  

Volvo Ocean Race 2014-15, Onboard Team Alvimedica. I’d hate to come across as being impossible to please but after days of wanting out of the doldrums, days of struggling with routines, with sleep, with a lack of regularity and consistency to our schedules, and of course--predictability to the weather—we’re 'out' and still trying to find it ... [more]  

Volvo Ocean Race 2014-15, Day 13 onboard Team SCA. I’m unsure if I should be nervous, excited, stressed, or thrilled today. As today I get to have fish guts smeared over me only to then become officially apart of King Neptune’s kingdom. ... [more]  

There was a shakeup at the top on day three of the 2014 RS:X Youth Worlds in Clearwater, Florida! Fully recharged thanks to the lay day yesterday, all competitors were eager to enter the final stretch of the competition in Clearwater, and the planing conditions in the forecast certainly contributed to the excitement on the beach. ... [more]  

The opening day of the 105-boat China Cup International Regatta saw old rivalries renewed in the Beneteau 40.7 class, as Vatti Sailing stole victory from Vanke Longcheer in the opening Simpson Marine Passage Race from Hong Kong to Shenzhen. ... [more]  

Team Alvimedica Navigational Strategist, Anderson Reggio, explains the issues ahead of the crews in the remaining half of leg 1 of the 2014-15 Volvo Ocean Race. After the Equator and Fernando, the weather looks to be shaping up to be pretty standard for the South Atlantic. The St Helena High which typically dominates this body of water is the main driver for breeze in the short term. ... [more]  

The next landmark, or ‘sea mark’ if you will, for Leg 1 is crossing the Equator, as Team Alvimedica continue to make their way south to round Fernando de Noronha off the coast of Brazil. Crossing this latitude is not like crossing any other on their way around the world, but has special significance for sailors who have never crossed the 0° parallel of latitude. ... [more]  

Volvo Ocean Race 2014-15 - Mapfre cruzará el Ecuador hacia las 13:00 aproximadamente. ... [more]  

Argo Group Gold Cup - A front slowly crossing Bermuda brought with it an overcast sky and rain squalls. Nonetheless, despite squelching their way ashore completely soaked, the Group 2 crews enjoyed the morning’s stronger breeze, the wind less shifty having veered into the southwest overnight, blowing down Hamilton Harbour rather than across it. ... [more]  

RenaissanceRe Junior Gold Cup - In second place, Adam Larson of Bermuda has seven points and had a great day on the water today. Larson, whose family is still without electricity after Hurricane Gonzalo, said he has been getting to bed a lot earlier these days and feels that the conditions also favored his performance today. ... [more]  

As predicted in last night's preview in Sail-World, the ORMA 60 TeamVodafone Sailing has set a new course record for the 119nm course in the PIC Coastal Classic. ... [more]  

Taylor Canfield (ISV) US One, top seed in Group 2, is the first skipper to qualify for the Quarter Finals in the 2014 Argo Group Cup. Canfield lost his first match in day one of racing against Chris Poole (USA) Riptide Racing. Since then the number two skipper on the Alpari World Match Racing Tour has sailed to seven straight points. ... [more]  

La Torche PWA Grand Slam - Waiting game continues on day 6
Volvo Ocean Race - Anything can happen in the Doldrums
Volvo Ocean Race - Abu Dhabi Ocean Racing first to exit the Doldrums
Volvo Ocean Race - Day 12 for Team Alvimedica
Rolex Sydney Hobart - Luna Sea 100th entry for 628 nautical mile race
Student Yachting World Cup - England emerges victorious
RORC Transatlantic Race fast approaching
Star Sailors League Finals - Three American greats to compete
America's Cup: Airbus and Oracle Team USA forge technology partnership
Rolex Middle Sea Race - Another dramatic day
Rolex Middle Sea Race - Artie confirmed as overall winner
Argo Group Gold Cup - Near perfect start for GAC Pindar
Volvo Ocean Race - A nightmare for sailors
The 2014 Severne Starboard Aloha Classic is coming...
Rolex Middle Sea Race 2014 - Artie's heroic return
Argo Group Gold Cup - Slender lead for Marek Stanczyk
Ben Ainslie Racing foiling on the Solent + Video *Feature
METS names DAME Award nominees
La Torche PWA Grand Slam - A day of rest for wave sailors
Rolex Middle Sea Race - A day of reckoning for the fleet
Volvo Ocean Race - Playing the Doldrums lottery   
Volvo Ocean Race - Dongfeng Race Team takes on the Doldrums   
Volvo Ocean Race - Team Alvimedica, somewhere in the windless ITCZ   
Rolex Middle Sea Race - Artie gunning for glory   
Volvo Ocean Race - Another perspective from Team SCA   
Rolex Farr 40 World Championship - Success in San Francisco   
RS:X Youth World Windsurfing Championship - Intense racing + Video   
Rolex Middle Sea Race - Big breeze and lumpy seas   
The first sail that changes lives   
Volvo Ocean Race: Blogs from the Boats - Leg 1, Day 10 plus Videos *Feature   
Volvo Ocean Race: Leg 1 turns inside out in Doldums *Feature   
34th Student Yachting World Cup La Rochelle 2014 - Fifth race day   
2014 Argo Group Gold Cup - Match racers defy Gonzalo   
Volvo Ocean Race: Big gains for two boats in Doldrums *Feature   
Argo Group Gold Cup - Qualifying Groups set   
Renaissance Re Junior Gold Cup - Kids breeze past Hurricane Gonzalo   
DSS to revolutionise IMOCA 60s, both new and old   
ISAF Sailing World Cup Miami: Groupe Beneteau sponsors US Sailing Team   
Volvo Ocean Race - The bright side of the Doldrums   
Volvo Ocean Race - Team Vestas Wind contemplates the tropics + Video   


For this week's complete news stories select    Last 7 Days
   Search All News
For last month's complete news stories select    Last 30 Days
   Archive News







Sail-World.com  


















Switch Default Region to:

Social Media

Asia

Australia

Canada

Europe

New Zealand

United Kingdom


http://www.sail-world.com/event_images/image/Twitter_logo_small.png http://www.sail-world.com/event_images/image/FaceBook-icon.png  http://www.sail-world.com/event_images/image/RSS-Icon.png

United States

Cruising Northern

Cruising Southern

MarineBusiness World

PowerBoat World

FishingBoating World

 

Contact

Commercial

News

Search

Contact Us

Advertisers Information

Submit news/events

Search Stories/Text

Feedback

Advertisers Directory

Newsletter Archive

Photo Gallery

 

Banner Advertising Details

Newsletter Subscribe

Video Gallery

Policies

 

 

 

Privacy Policy

 

 


Cookie Policy

 

 



This site and its contents are © Copyright TetraMedia and/or the original author, photographer etc. All Rights Reserved.  Photographs are copyright by law.  If you wish to use or buy a photograph contact the photographer directly.
XLXL WAS US
LocalAds   DE  ES  FR  IT