A record-breaking school of mobular rays has arrived off the coast of Baja.
Saturday, May 24, 2014
Friday, May 23, 2014
Science graphic of the week: Monitoring ocean waves from space
Image credit: ESA/DLR (Animation: WIRED)
Ships, oil platforms and offshore wind farms are threatened by rough seas.
Information provided by radar satellites can support the detection and forecast of extreme wave heights.
From Wired by Betsy Mason
The radar instruments on some satellites can be used to gather all sorts of interesting information.
The animation above (see video) illustrates wave heights in the North Sea that were derived from satellite radar measurements.
Wave height and frequency in a large body of water are largely dependent on the speed of the wind moving across the surface.
Satellites with specialized radar sensors can measure wind speed by looking at the ocean surface from several angles as it passes over.
The radar detects the reflectivity of the water, which is determined by the roughness of the surface.
Higher reflectivity means rougher water, which is caused by stronger winds.
Wind direction can be estimated by looking at wind streaks in radar images of the water’s surface.
In response to threats from extreme waves to ships, oil platforms and wind farms in the North Sea, the European Space Agency is using its satellites to monitor the roughness of the sea surface to help spot big waves and feed computer models that try to forecast dangerous waves.
Thursday, May 22, 2014
Brazil DHN update in the Marine GeoGarage
As our public viewer is not yet available
(currently under construction, upgrading to Google Maps API v3 as v2 is officially no more supported),
this info is primarily intended to our Phone/iPad universal mobile application users
(Marine Brazil on the App Store)
and also to our B2B customerswhich use our nautical charts layers
in their own webmapping applications through our GeoGarage API.
(currently under construction, upgrading to Google Maps API v3 as v2 is officially no more supported),
this info is primarily intended to our Phone/iPad universal mobile application users
(Marine Brazil on the App Store)
and also to our B2B customerswhich use our nautical charts layers
in their own webmapping applications through our GeoGarage API.
21 charts have been updated and 5 charts added since the last update
DHN update May 05, 2014
(with updates 01/04, 02/04 & 09/04)
- 830 PORTO DE CABEDELO
- 906 PORTO DE SUAPE
- 1001 PORTO DE BARRA DOS COQUEIROS
- 1100 DO RIO ITARIRI A ILHEUS
- 1110 BAÍA DE TODOS OS SANTOS
- 1621 BAÍA DA ILHA GRANDE - PARTE LESTE (TERMINAL DA ILHA GUAÍBA)
- 21040 DE NATAL AO RIO ITARIRI
- 23400 DE IMBITUBA A PINHAL
- 1821 BARRA DE PARANAGUÁ
- 1103 BAÍA DE ARATU E ADJACÊNCIAS
- 1104 BAÍA DE TODOS OS SANTOS PARTE NORDESTE
- 1402 DO PONTAL DA REGÊNCIA À PONTA DO UBU
- 22000 ATOL DAS ROCAS E ARQUIPÉLAGO DE FERNANDO DE NORONHA
- 19400 DO RECIFE A DACAR NEW
- 22300 DE MACEIÓ A ARACAJU
- 2792 LAGO DE BRASÍLIA
- 2010 PROXIMIDADES DE TRAMANDAÍ NEW
- 1101 PROXIMIDADES DO PORTO DE SALVADOR
- 1407 CANAL DE SÃO TOMÉ NEW
- 810 PROXIMIDADES DO PORTO DE NATAL
- 321 PORTO DE VILA DO CONDE NEW
- 4103A DE PRAINHA À COSTA DO ITUQUI
- 1643 CANAL DE SÃO SEBASTIÃO (PARTE NORTE)
- 1909 DA ILHA DAS ARARAS AO CABO DE SANTA MARTA GRANDE
- 1910 DA ILHA DE CORAL AO CABO DE SANTA MARTA GRANDE
- 25121 ILHAS SHETLAND DO SUL - BAÍA DO ALMIRANTADO (ILHA REI GEORGE)
Today 439 charts (486 including sub-charts) from DHN are displayed in the Marine GeoGarage
Don't forget to visit the NtM Notices to Mariners (Avisos aos Navegantes)
First-ever study describes deep-sea animal communities on and around a sunken shipping container
Thousands of shipping containers are lost from cargo vessels each year. Many of these containers eventually sink to the deep seafloor.
In 2004, researchers at the Monterey Bay Aquarium Research Institute (MBARI) discovered a lost shipping container almost 1,300 meters (4,200 feet) below the surface of the Monterey Bay National Marine Sanctuary.
In the first ever survey of its kind, researchers from MBARI and the Sanctuary recently described how deep-sea animal communities on and around the container differed from those in surrounding areas.
The red dots seen in some of the underwater footage are lasers mounted on the remotely operated submersible.
The lasers are 29 cm apart and allow the scientists to estimate animal size.
In 2004, researchers at the Monterey Bay Aquarium Research Institute (MBARI) discovered a lost shipping container almost 1,300 meters (4,200 feet) below the surface of the Monterey Bay National Marine Sanctuary.
In the first ever survey of its kind, researchers from MBARI and the Sanctuary recently described how deep-sea animal communities on and around the container differed from those in surrounding areas.
The red dots seen in some of the underwater footage are lasers mounted on the remotely operated submersible.
The lasers are 29 cm apart and allow the scientists to estimate animal size.
From MBARI
Thousands of shipping containers are lost from cargo vessels each year. Many of these containers eventually sink to the deep seafloor.
In 2004, scientists at the Monterey Bay Aquarium Research Institute (MBARI) discovered a lost shipping container almost 1,300 meters (4,200 feet) below the surface of the Monterey Bay National Marine Sanctuary.
In the first-ever survey of its kind, researchers from MBARI and the sanctuary recently described how deep-sea animal communities on and around the container differed from those in surrounding areas.
In February 2004, the cargo vessel Med Taipei was traveling southward along the California coast when severe winds and seas dislodged 24 shipping containers, 15 of which were lost within the boundaries of the Monterey Bay National Marine Sanctuary.
Four months later, during a routine research dive using the remotely operated vehicle (ROV) Ventana, MBARI scientists discovered one of these containers on the seafloor.
In March 2011, a research team led by Andrew DeVogelaere of the sanctuary and Jim Barry of MBARI completed another ROV dive at the container.
During this dive, they collected extensive video footage, as well as samples of seafloor sediment at various distances from the container.
They then compared the animals found on the container, on the nearby seafloor, and on the surrounding seafloor out to 500 meters (a third of a mile) away from the container.
In early May, 2014 they published their findings in the journal Marine Pollution Bulletin.
Josi Taylor, the lead author of the recent article, said that she was surprised to see how little the container had corroded in the seven years since it sank to the seafloor.
Apparently, the near-freezing water and low oxygen concentrations in the deep sea slowed the processes that might degrade sunken containers in shallower water.
As expected, the hard surface of the container acted somewhat like a rocky reef, attracting animals such as tubeworms, scallops, snails, and tunicates.
Such animals require hard surfaces on which to attach, and were not found on the muddy seafloor around the container. Surprisingly, several types of animals found on nearby rocky reefs, such as sponges, soft corals, and crinoids (a distant relative of sea stars), had not colonized the surface of the container.
In their paper, the researchers speculate that some of these slow-growing animals might not have had enough time to colonize the container’s surface.
Another possible explanation is that some types of animals may be sensitive to the potentially toxic effects of corrosion-resistant coatings used on shipping containers.
The team conducted a follow-up ROV dive in December 2013 to study possible effects of the container’s coating.
The samples from this dive are still being analyzed.
The researchers also discovered differences in the types of animals living on the muddy seafloor within about 10 meters (32 feet) of the container.
Within this zone, deep-sea snails in the genus Neptunea and some types of crabs and fish, including deep-sea rockfish, were more abundant than in surrounding areas, while sea pens and other filter feeders were less abundant.
Overall, the paper shows that the container caused shifts in animal communities through a variety of processes. Its physical presence provided:
For example, higher numbers of seafloor predators near the container might explain some of the changes in the types of other animals found on the nearby seafloor.
Such indirect ecological effects might also explain why the diversity of seafloor animals was lower near the container.
This collaborative research project has already helped government agencies in formulating standards for how containers are weighed, stacked, and lashed down.
It has also spurred interest from both governmental agencies and the shipping industry in finding a way to track the number of containers lost at sea each year.
As DeVogelaere noted, “The fact that our research was mentioned by the U.S. Coast Guard in the background material for a proposed lashing rule shows that this work has clear societal value.”
During future dives to the container, the researchers hope to find out whether more diverse animal communities will develop over time, or if some toxic material is allowing only certain hardy animals to colonize the container.
They are also designing a study to compare the effects of different types of container coatings on colonization by deep-sea animals.
This particular container held a shipment of car tires.
Other containers are used to transport more acutely toxic materials, such as batteries, pesticides, and raw chemicals.
These substances would only add to the possible effects of a sunken container.
Given the slow rate at which the sunken container is corroding, and evidence from deep-sea shipwrecks such as the Titanic, the researchers hypothesize that lost containers may take hundreds of years to fully degrade in the deep sea.
This suggests that each year thousands of shipping containers are accumulating on the deep seafloor, especially along busy shipping routes.
Taylor said, “We have only begun to characterize the potential long-term impacts of a single container on a deep-sea community. Although the effects of one container may seem small, the thousands of shipping containers lost on the seafloor each year could eventually become a significant source of pollution for deep-sea ecosystems.”
Links :
Thousands of shipping containers are lost from cargo vessels each year. Many of these containers eventually sink to the deep seafloor.
In 2004, scientists at the Monterey Bay Aquarium Research Institute (MBARI) discovered a lost shipping container almost 1,300 meters (4,200 feet) below the surface of the Monterey Bay National Marine Sanctuary.
In the first-ever survey of its kind, researchers from MBARI and the sanctuary recently described how deep-sea animal communities on and around the container differed from those in surrounding areas.
In February 2004, the cargo vessel Med Taipei was traveling southward along the California coast when severe winds and seas dislodged 24 shipping containers, 15 of which were lost within the boundaries of the Monterey Bay National Marine Sanctuary.
Four months later, during a routine research dive using the remotely operated vehicle (ROV) Ventana, MBARI scientists discovered one of these containers on the seafloor.
In March 2011, a research team led by Andrew DeVogelaere of the sanctuary and Jim Barry of MBARI completed another ROV dive at the container.
During this dive, they collected extensive video footage, as well as samples of seafloor sediment at various distances from the container.
They then compared the animals found on the container, on the nearby seafloor, and on the surrounding seafloor out to 500 meters (a third of a mile) away from the container.
In early May, 2014 they published their findings in the journal Marine Pollution Bulletin.
Josi Taylor, the lead author of the recent article, said that she was surprised to see how little the container had corroded in the seven years since it sank to the seafloor.
Apparently, the near-freezing water and low oxygen concentrations in the deep sea slowed the processes that might degrade sunken containers in shallower water.
As expected, the hard surface of the container acted somewhat like a rocky reef, attracting animals such as tubeworms, scallops, snails, and tunicates.
Such animals require hard surfaces on which to attach, and were not found on the muddy seafloor around the container. Surprisingly, several types of animals found on nearby rocky reefs, such as sponges, soft corals, and crinoids (a distant relative of sea stars), had not colonized the surface of the container.
In their paper, the researchers speculate that some of these slow-growing animals might not have had enough time to colonize the container’s surface.
Another possible explanation is that some types of animals may be sensitive to the potentially toxic effects of corrosion-resistant coatings used on shipping containers.
The team conducted a follow-up ROV dive in December 2013 to study possible effects of the container’s coating.
The samples from this dive are still being analyzed.
The researchers also discovered differences in the types of animals living on the muddy seafloor within about 10 meters (32 feet) of the container.
Within this zone, deep-sea snails in the genus Neptunea and some types of crabs and fish, including deep-sea rockfish, were more abundant than in surrounding areas, while sea pens and other filter feeders were less abundant.
Overall, the paper shows that the container caused shifts in animal communities through a variety of processes. Its physical presence provided:
- a hard surface that sessile (attached) animals colonized;
- a physical obstacle that affected local bottom currents,
- a high spot on the seafloor that attracted predators, and
- a possible source of toxic materials.
For example, higher numbers of seafloor predators near the container might explain some of the changes in the types of other animals found on the nearby seafloor.
Such indirect ecological effects might also explain why the diversity of seafloor animals was lower near the container.
This collaborative research project has already helped government agencies in formulating standards for how containers are weighed, stacked, and lashed down.
It has also spurred interest from both governmental agencies and the shipping industry in finding a way to track the number of containers lost at sea each year.
As DeVogelaere noted, “The fact that our research was mentioned by the U.S. Coast Guard in the background material for a proposed lashing rule shows that this work has clear societal value.”
During future dives to the container, the researchers hope to find out whether more diverse animal communities will develop over time, or if some toxic material is allowing only certain hardy animals to colonize the container.
They are also designing a study to compare the effects of different types of container coatings on colonization by deep-sea animals.
This particular container held a shipment of car tires.
Other containers are used to transport more acutely toxic materials, such as batteries, pesticides, and raw chemicals.
These substances would only add to the possible effects of a sunken container.
Given the slow rate at which the sunken container is corroding, and evidence from deep-sea shipwrecks such as the Titanic, the researchers hypothesize that lost containers may take hundreds of years to fully degrade in the deep sea.
This suggests that each year thousands of shipping containers are accumulating on the deep seafloor, especially along busy shipping routes.
Taylor said, “We have only begun to characterize the potential long-term impacts of a single container on a deep-sea community. Although the effects of one container may seem small, the thousands of shipping containers lost on the seafloor each year could eventually become a significant source of pollution for deep-sea ecosystems.”
Links :
- GeoGarage blog : Trash in the deep sea: bringing a hidden problem to light
Wednesday, May 21, 2014
US NOAA update in the Marine GeoGarage
As our public viewer is not yet available
(currently under construction, upgrading to Google Maps API v3 as v2 is officially no more supported),
this info is primarily intended to our iPhone/iPad universal mobile application users
(Marine US on the App Store)
and also to our B2B customers which use our nautical charts layers in their own webmapping applications through our GeoGarage API.
(currently under construction, upgrading to Google Maps API v3 as v2 is officially no more supported),
this info is primarily intended to our iPhone/iPad universal mobile application users
(Marine US on the App Store)
and also to our B2B customers which use our nautical charts layers in their own webmapping applications through our GeoGarage API.
35 charts have been updated in the Marine GeoGarage
(NOAA update April 2014)- 11357 ed46 Timbalier and Terrebonne Bays
- 11358 ed7 Barataria Bay and approaches
- 11364 ed44 Mississippi River-Venice to New Orleans
- 11385 ed23 Intracoastal Waterway West Bay to Santa Rosa Sound
- 12205 ed106 FOLIO SMALL-CRAFT CHART Cape Henry to Pamlico Sound. Including Albemarle Sd.;Rudee Heights
- 12273 ed60 Chesapeake Bay Sandy Point to Susquehanna River
- 12278 ed18 Chesapeake Bay Approaches to Baltimore Harbor
- 12281 ed42 Baltimore Harbor
- 13009 ed25 Gulf of Maine and Georges Bank
- 13204 ed25 Georges Bank Eastern part
- 13230 ed28 Buzzards Bay; Quicks Hole
- 16322 ed32 Bristol Bay-Nushagak B and approaches
- 16434 ed26 Agattu Island
- 16435 ed23 Semichi Islands Alaid and Nizki Islands
- 16513 ed12 Unalaska Island Umnak Pass and approaches
- 16514 ed29 Kulikak Bay and Surveyor Bay
- 16515 ed18 Chernofski Harbor to Skan Bay
- 16518 ed22 Cape Kavrizhka to Cape Cheerful
- 17303 ed40 Yakobi Island and Lisianski Inlet;Pelican Harbor
- 17321 ed36 Cape Edward to Lisianski Strait. Chichagof Island
- 17322 ed82 Khaz Bay. Chichagof Island Elbow Passage
- 17363 ed30 Pybus Bay. Frederick Sound;Hobart and Windham Bays. Stephens P.
- 17377 ed34 Le Conte Bay
- 17378 ed11 Port Protection. Prince of Wales Island
- 17379 ed30 Shaken Bay And Strait. Alaska
- 17403 ed17 Davidson Inlet and Sea Otter Sound;Edna Bay
- 17433 ed28 Kendrick Bay to SHipwreck Point. Prince of Wales Island
- 17435 ed28 Harbors in Clarence Strait Port Chester. Annette Island;Tamgas Harbor. Annette Island;Metlakatla Harbor
- 17437 ed25 Portland Inlet to Nakat Bay
- 18429 ed37 Rosario Strait-southern part
- 18431 ed34 Rosario Stait to Cherry Point
- 19367 ed22 Island of O'ahu Honolulu Harbor
- 81086 ed51 Plans in the Mariana Islands (Metric) Faraloon de Pajaros;Sarigan Island;Farallon de Medinilla;Ascuncion Island;Agrihan;Agrihan Anchorge;Alamagan Island;Guguan;Anatahan
- 81664 ed57 Wake Island;Wake Island Boat Basin
- 13230 ed38 Buzzards Bay; Quicks Hole
How do you know if you need a new nautical chart?
See the changes in new chart editions.
NOAA chart dates of recent Print on Demand editions
Note : NOAA updates their nautical charts with corrections published in:
- U.S. Coast Guard Local Notices to Mariners (LNMs),
- National Geospatial-Intelligence Agency Notices to Mariners (NMs), and
- Canadian Coast Guard Notices to Mariners (CNMs)
Please visit the NOAA's chart update service for more info or the online chart catalog
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