Coast Survey unveils easier access to wreck information

AWOIS on Google Maps

From NOAA

Maintaining documentation for features depicted on nautical charts is more complicated than you probably imagine.
For instance, Coast Survey maintains information on more than 10,000 submerged wrecks and obstructions in U.S. coastal waters – and it just got easier for the public to access that free information.

Coast Survey uses our Automated Wreck and Obstruction Information System (AWOIS) to help plan hydrographic survey operations and to catalog the many reported wrecks and obstructions considered navigational hazards within U.S. coastal waters.
The public also has access to this rich information source.
Marine archaeologists and historians, fishermen, divers, salvage operators, and others in the marine community find AWOIS valuable as an historical record of selected wrecks and obstructions.

Information contained in the database includes latitude and longitude of each feature, along with brief historic and descriptive details.
Until recently, that information was available for download in Microsoft Access MDB and Adobe PDF format.
However, these formats were difficult to search.

As of today, AWOIS information will no longer be available in MDB or PDF format.
Instead, users can download AWOIS files in the more useful Google Earth Keyhole Markup Language (KML) format.
KML is an XML grammar and file format for modeling and storing geographic features such as points, lines, images, polygons, and models for display in Google Earth, Google Maps, and other applications. (KML is an international standard, maintained by Open Geospatial Consortium, Inc.)

example of the information that will be displayed by clicking on a AWOIS item

Once you download an AWOIS file, you can open that file directly in a mapping application, such as Google Earth or Google Maps.
You can then navigate directly to your area of interest and obtain information about individual features.
Clicking on any AWOIS item will bring up additional information, such feature type, position, and history.

AWOIS file opened in Google Earth

In wake of Sandy, NOAA alters hurricane warning policy

NOAA's GOES-13 satellite captured this visible image of the massive Hurricane Sandy on Oct. 28 at 1615 UTC (12:02 p.m. EDT).

The line of clouds from the Gulf of Mexico north are associated with the cold front that Sandy is merging with.

Sandy's western cloud edge was already over the Mid-Atlantic and northeastern U.S.
Credit: NASA GOES Project

From ClimateCentral 

Ahead of the 2013 Atlantic Hurricane Season and in the wake of Hurricane Sandy, the National Weather Service announced Thursday that it is changing its policy on the issuance of tropical storm and hurricane watches and warnings.
The changes will give forecasters more flexibility in issuing hurricane warnings, and streamline the authority for issuing such warnings.

Beginning on June 1, the agency will be permitted to leave watches and warnings in effect even if a hurricane transitions into a post-tropical cyclone, which technically speaking is a different type of storm than a storm of purely tropical origins, provided that the storm still poses “a significant threat to life and property.”

The agency’s procedures came under criticism after forecasters decided not to issue hurricane warnings as Hurricane Sandy approached the Mid-Atlantic coast, since the storm was transitioning from a hurricane into a post-tropical storm.
Based on policies in place at the time, forecasters would have had to cancel hurricane warnings once the storm completed that transition, and they feared that would confuse the public and the emergency management community.

However, critics argue that by not issuing hurricane warnings at all, and instead posting a plethora of high wind, coastal flooding, and other watches and warnings, the Weather Service may have downplayed the risks from Sandy, and caused some people to remain in their homes that were then subject to the storm’s record storm surge along the New Jersey, New York, and Connecticut coastlines.
According to a recent report from the reinsurance company Swiss Re, Sandy caused an estimated $70 billion in total damage and $35 billion in insured losses.

The lack of hurricane warnings during Sandy also has had implications for the insurance industry, since most hurricane-insurance policies contain deductibles that only kick in if a hurricane warning is in effect at the time that the home is damaged.
This means that insurance companies may be on the hook for a greater percentage of losses than if a warning had been issued.

In addition to allowing tropical storm and hurricane watches and warnings to remain in effect after a hurricane transitions into a different type of storm, the new policy would keep the National Hurricane Center in Miami in charge of all forecast products until the storm no longer poses a significant threat. During Hurricane Sandy, responsibility was passed from the Hurricane Center to local NWS offices, which resulted in inconsistent communications and warnings being issued from one state to another.

“Our forecasters now have more flexibility to effectively communicate the threat posed by transitioning tropical systems,” NWS director Louis W. Uccellini said.
“Sandy’s forecast was remarkably accurate and under a similar situation in the future, forecasters will be able to choose the best option to underscore the urgency involved.”

According to an NWS statement, the policy change, which was first proposed during an annual NOAA hurricane conference in November, is supported by preliminary findings from NOAA’s service assessment on Sandy, which is slated to be released in May.
The NWS released an example of a statement that would be issued for a hypothetical hurricane named "Mandy," which states: "Mandy loses tropical characteristics but hurricane warnings remain in effect. Mandy expected to bring life-threatening storm surge and hurricane-force winds to the coast this afternoon."

Links :

• LiveSciences : Perfect Storm: Climate Change and Hurricanes
• Accuweather : No hurricane warning for what could be the most expensive storm in history
  

Canada CHS update in the Marine GeoGarage

4116 Approaches to Saint John

23 charts have been updated (March 29, 2013) :

• 1312 LAC SAINT-PIERRE
• 1313 BATISCAN TO LAC SAINT-PIERRE
• 1430 LAC SAINT-LOUIS
• 2100 LAKE ERIE
• 2121 LONG POINT TO PORT GLASGOW
• 2181 HARBOURS IN LAKE ERIE
• 2202A PORT SEVERN TO TOMAHAWK ISLAND
• 2202B TOMAHAWK ISLAND TO TWELVE MILE BAY
• 2202C TWELVE MILE BAY TO ROSE ISLAND
• 2202D SOUTH CHANNEL AMANDA ISLAND TO PARRY SOUND
• 2202E MOON ISLAND AND SURROUNDING AREAS
• 3424 APPROACHES TO OAK BAY
• 3440 RACE ROCKS TO D'ARCY ISLAND
• 3462 JUAN DE FUCA STRAIT TO STRAIT OF GEORGIA
• 4012 YARMOUTH TO HALIFAX
• 4013 HALIFAX TO SYDNEY
• 4115 PASSAMAQUODDY BAY AND ST CROIX RIVER
• 4116 APPROACHES TO SAINT JOHN
• 4237 APPROACHES TO HALIFAX HARBOUR
• 4320 EGG ISLAND TO WEST IRONBOUND ISLAND
• 4375 GUYON ISLAND TO FLINT ISLAND
• 4462 ST. GEORGE'S BAY
• 4850 CAPE ST FRANCIS TO BACCALIEU ISLAND AND HEART'S CONTENT

So 688 charts (1658 including sub-charts) are available in the Canada CHS layer. (see coverage)

Note : don't forget to visit 'Notices to Mariners' published monthly and available from the Canadian Coast Guard both online or through a free hardcopy subscription service.
This essential publication provides the latest information on changes to the aids to navigation system, as well as updates from CHS regarding CHS charts and publications.
See also written Notices to Shipping and Navarea warnings : NOTSHIP

Each year, a land area larger than Manhattan disappears off Louisiana's coast

>>> geolocalization with the Marine GeoGarage <<<

From NOAA

Every year, 25-35 square miles of land off the coast of Louisiana—an area larger than Manhattan–disappears into the water due to a combination of subsidence (soil settling) and global sea level rise.
The maps above show how much land has been lost to the Gulf of Mexico in the past 80 years.

The first image shows the state of the coast in 2011.

Based on a NASA satellite image, gray and white areas show land and blue indicates open water. New land—mainly coastal improvements such as shoreline revetments and enriched beach areas—that built up since 1932 is shown in green.

How much of what is now open water was once land?

The second image shows the state of the coast in 1932.

The image combines the 2011 satellite image with a U.S. Geological Survey map in which land areas that were present in 1932 are light gray.
Since the 1930s, Louisiana's coast has lost 1,900 square miles of land, primarily marshes.
The two maps reveals the dramatic coastal change.

In Southeast Louisiana, relative sea level is rising at a rate of three feet every one hundred years, according to sixty years of tidal gauge records.
Relative sea level refers to the change in sea level compared to the elevation of the land, which can be due to a combination of global sea level rise and subsidence—the settling and sinking of soil over time.

Storm surge—the water from the ocean that is pushed toward the shore by the force of storm winds—takes advantage of the problems caused by subsidence and global sea level rise.
Because much of the Louisiana coast is very low in elevation and gradually converting to open water, entire neighborhoods, roads, and other structures are vulnerable to even small storm events.

At the very tip of the coast lies Port Fourchon—one of the country's major ports serving the deepwater oil and gas industry in the Gulf of Mexico.
Next to it is Grand Isle, the last inhabited barrier island in Louisiana.
Various beach restoration projects over the years have helped build up and maintain Grand Isle and other Louisiana's barrier islands.
They are the first line of defense against storms headed toward the mainland and New Orleans.

The Louisiana Highway 1 is the only road leading to Port Fourchon and Grand Isle.
While the port sits on a five-foot ridge, much of the LA-1 highway is built on land only two feet in elevation.
The highway is growing increasingly vulnerable to sea level rise, subsidence, and storm surge every year.
One section of the road is so low that even small storm events cause flooding that makes it impassable.
Disruptions to the infrastructure surrounding the port have the potential to impact every American at the gas pump.

Sea level rise in Louisiana is a challenge today, not just one for the future, and a wide group of people and organizations are helping develop solutions.
Want to know more?
Our recent feature story, "Thriving on a Sinking Landscape," provides an in-depth look at what is at stake for locals and the rest of the country if the LA-1, 'America's longest Main Street,' fails to stay above water.

Tidal flats and channels on Long Island, Bahamas

Tidal flats and channels on Long Island, Bahamas are featured in this image
photographed by an Expedition 26 crew member on the International Space Station 
(NASA, 27 November 2010)

The islands of the Bahamas in the Caribbean Sea are situated on large depositional platforms (the Great and Little Bahama Banks) composed mainly of carbonate sediments ringed by fringing reefs – the islands themselves are only the parts of the platform currently exposed above sea level.
The sediments are formed mostly from the skeletal remains of organisms settling to the sea floor; over geologic time, these sediments will consolidate to form carbonate sedimentary rocks such as limestone.

 >>> geolocalization with the Marine GeoGarage <<<

This detailed photograph provides a view of tidal flats and tidal channels near Sandy Cay on the western side of Long Island, located along the eastern margin of the Great Bahama Bank.
The continually exposed parts of the island have a brown coloration in the image, a result of soil formation and vegetation growth (left).

To the north of Sandy Cay an off-white tidal flat composed of carbonate sediments is visible; light blue-green regions indicate shallow water on the tidal flat.
Tidal flow of seawater is concentrated through gaps in the anchored land surface, leading to formation of relatively deep tidal channels that cut into the sediments of the tidal flat.
The channels, and areas to the south of the island, have a vivid blue coloration that provides a clear indication of deeper water (center).