This wind-powered commuter ferry is built like a racing boat

The Trillizas, a trimaran owned by Jay and Pam Gardner of Napa, is a testing bed for the WingSail, a 40-foot-tall rigid sail that allows a boat to propel itself using less engine power for reduced air pollution.

After Bay Area testing that began in February 2014, the WingSail project, which has received funds from regional and state air quality authorities, had its public debut in May 2014 in San Francisco. Wind+Wing Technologies photo

From Popular Science by Katherine Kornei

For all their convenience, most commuter ferries are dirty machines.
A high-speed one burns 6,600 gallons of fuel a day, on average.
Multiply that by the number of passenger boats on a busy waterway, like San Francisco Bay, and you’ve got a lot of spent diesel.
“You can drive your Cadillac Escalade across the Golden Gate Bridge and get 19 miles to the gallon and you’d still be far more environmentally correct than to take the ferry system in the way it’s currently operated,” says Jay Gardner, president of Wind+Wing Technologies (WWT) in Napa, California.
Gardner claims his company can reduce that diesel consumption by up to 40 percent.

WWT is developing a ferry that makes use of an abundant--and free--natural resource: wind.
Instead of relying solely on engine power, specially designed catamarans
 will be equipped with vertical carbon-fiber “wing sails” similar to those introduced in the last America’s Cup sailing race.

The substantial area of the wings--nearly 3,000 square feet--will catch up to 72,000 pounds of wind force.
(WWT is working with nautical engineers to ensure the ferries remain stable by designing interior bulkheads that have textured ribbing, which disperses these large forces over the two hulls of the boats.)
The wings will be equipped with GPS systems and vessel data recorders, and powered by photovoltaic cells.
Used in conjunction with an electric or clean diesel engine, the wings automatically adjust position to capture the wind, providing additional propulsion.
Unlike traditional cloth sails, the wings require no expertise to operate, which has been a big stumbling block for wind-powered commercial vessels in the past.
When ferryboat operators want to disengage the wings, such as during docking or especially windy conditions, they won’t have to fold them down.
Instead, crew members can simply set the wings in a neutral position. Even better, the process of using and disengaging the wings is completely autonomous.
“The crew doesn’t need to know anything about the wing or how it works,” explains Richard Jenkins, president of Photon Composites, the company constructing the wings.
“It’s literally an on-off system.”

WWT plans to outfit custom, 149-passenger ferryboats with two 75-foot-tall wings.
Ultimately, the design can be scaled up to carry 500 passengers.
And while 
$2 million for a pair of wings ain’t cheap, WWT says they would likely pay for themselves in fuel savings in less than two years.
The company has already run tests on a smaller 42-foot prototype vessel and is now in talks with public and private investors to service the route between San Francisco and Treasure Island
 The project could be live by 2020.
Finally, ferryboat travel will be befitting of a modern, environmentally conscious city.

How It Works

Illustration by Graham Murdoch

1. Wing : Each wing weighs about 4,000 pounds and is connected to the vessel by a 75-foot spine that turns freely. Three microphones measure audio signals from the wind. A computer then analyzes the readings to determine the wind’s direction.
2. Trim Tab : Based on real-time wind direction, an actuator offsets the thin, outermost piece on the top of the wing by 15 degrees. This action forces the trim tab to move the wing, which provides thrust to the ferry, propelling it forward.
3. Counterweight : A 200-pound lead beam balances the weight of the wing, making it sensitive to even tiny changes in wind direction.
4. Solar Cell : A nine-square-foot photovoltaic cell generates about 50 watts of power to operate the wind sensor, wing controls, GPS, and communication tools.5.
5. Bulkhead : Unlike traditional sailboats, these ferries need an interior bulkhead that runs the width of the catamaran. It will evenly disperse the wings’ force on the boat--up to 72,000 pounds--between the two hulls to ensure stability.

Links :

• GeoGarage blog :  The drone that will sail itself around the world / Wind turbine concept ties-in 'America's Cup' technology

Rounding Cape Horn | Volvo Ocean Race 2014-15

On Monday, the Volvo Ocean Race fleet will round the infamous Cape Horn

 courtesy of Jean-Arnold (Volodiaja) 29/12/2015 12:40

 Cabo de Hornos with the Marine GeoGarage

I met my husband in the middle of the sea

I Met My Husband in the Middle of the Sea from olivia wyatt

For the Moken people of Southeast Asia, the sea provides nearly everything a person might need.
It offers food to eat, a comfortable place to live (assuming one owns the appropriate vessel), and, sometimes, love.
Members of this ocean-faring ethnic group – often called “Sea Gypsies” – roam the Andaman Sea off the coasts of Thailand and Myanmar.

The Moken travel on small, handcrafted wooden boats called kabangs, from which they skillfully procure fresh meals of fish, scallops, and clams, using nothing more complicated than a simple spear and a remarkable ability to hold their breath.
To see the full story: junglesinparis.com/stories/49

This film was edited exclusively for Jungles in Paris using footage from the feature "Sailing a Sinking Sea"(2015), which premieres at SXSW March 2015..
Feature film website: cargocollective.com/sailingasinkingsea

Links :

• GeoGarage blog : What freediving does to the body

 

Antarctic ice shelves are melting dramatically, study finds

A new study published by Science and led by Scripps Institution of Oceanography at UC San Diego researchers has revealed that the thickness of Antarctica’s floating ice shelves has recently decreased by as much as 18 percent in certain areas over nearly two decades, providing new insights on how the Antarctic ice sheet is responding to climate change.
Data from nearly two decades of satellite missions have shown that the ice volume decline is accelerating.

From The Guardian by Karl Mathiesen

Melting of floating ice shelves around the continent is accelerating, potentially unlocking extra sea level rise from larger ice sheets jammed behind them

The ice around the edge of Antarctica is melting faster than previously thought, potentially unlocking metres of sea-level rise in the long-term, researchers have warned.

A team of US scientists looked at 18 years’ worth of satellite data and found the floating ice shelves that skirt the continent are losing 310km³ of ice every year.

One shelf lost 18% of its thickness during the period.

The loss of ice shelves does not contribute much directly to sea level rise.

But they act like a cork in a bottle at the point where glaciers meet the sea – jamming the flow of ice from the massive ice sheets of east and west Antarctica.

 Satellite view of a large iceberg separating from Antarctica’s Pine Island Glacier, where ice loss has doubled in speed over the last 20 years.

Photograph: MODIS/Aqua/NASA

Professor Andrew Shepherd, director of the Centre for Polar Observation and Modelling at the University of Leeds, said the rates of ice loss were unsustainable and could cause a major collapse.

This is already occurring at the massive Pine Island glacier, where ice loss has doubled in speed over the last 20 years as its blocking ice shelf has melted.

“This is a real concern, because such high rates of thinning cannot be sustained for much longer, and because in the places where Antarctic ice shelves have already collapsed this has triggered rapid increases in the rate of ice loss from glaciers above ground, causing global sea levels to rise,” he said. 

 Changes to the thickness and volume of Antarctica's ice shelves between 1994 and 2012.

Credit: Paolo, et al./Science

The new research, published in the journal Science on Thursday, discovered for the first time that ice shelf melt is accelerating.

Dr Paul Holland, a climate scientist at the British Antarctic Survey (BAS), said the loss of the shelves would speed the complete collapse of the west Antarctic ice sheet, which would eventually cause up to 3.5m of sea level rise.

But he said it was highly unlikely this would occur this century.

He said the “worst case scenario” for 2100 was that ice sheets would contribute an additional 70cm to the sea level rise caused by the warming of the ocean.

 Antarctica's Brunt Ice Shelf.

Credit: Michael Studinger/NASA.

The UN’s climate science body has not previously included the ice sheets of Antarctica and Greenland in its predictions for future sea level rise because scientists are not certain how fast they will slide into the ocean.

 Pine Island Glacier on Sentinel-1A’s radar

This image combining two scans by Sentinel-1A’s radar shows that parts of the Pine Island glacier flowed about 100 m (in pink) between 3 March and 15 March 2015.

Light blue represents stable ice on either side of the stream.
Pine Island is the largest glacier in the West Antarctic Ice Sheet and one of the fastest ice streams on the continent, with an average of over 4 km per year.

About a tenth of the ice sheet drains out to the sea by way of this glacier.
With its all-weather, day and night radar vision, the Sentinel-1 mission is an important tool for monitoring polar regions and the effects that climate change has on ice.

Holland said: “What humanity needs to know is what’s the sea level rise in 2100 and the biggest source of uncertainty in that is what’s going to happen to the ice sheets.”

Over the past decade the loss of ice shelf volume in Antarctica increased from 25km³ to 310km³ every year.

It is unclear whether the loss of ice is directly related to man-made climate change or a cyclical change in ocean currents.

But the extra sea level rise from ice sheets will exacerbate the rise caused by the expansion of oceans as the world warms.

Professor David Vaughan, director of science at BAS, said the findings would help scientists to make more accurate predictions about future sea level rise.

“The rate of ice loss, especially when considered in terms of the percentage of ice lost in the last two decades, is dramatic. This research is a significant step towards improving our ability to predict the future of the Antarctic ice sheet and its contribution to global sea level rise.”

 Schematic diagram of an Antarctic ice shelf showing the processes causing the volume changes measured by satellites.

Ice is added to the ice shelf by glaciers flowing off the continent and by snowfall that compresses to form ice.

Ice is lost when icebergs break off the ice front, and by melting in some regions as warm water flows into the ocean cavity under the ice shelf.

Under some ice shelves, cold and fresh meltwater rises to a point where it refreezes onto the ice shelf.

Helen Amanda Fricker, Professor, Scripps Institution of Oceanography, UC San Diego, Author provided

The western coast ice shelves contributed the majority of the ice loss.

The rate of loss increased by 70% in the last decade.

Two shelves in this region could completely disappear within a century.

Conversely, there were some areas in east Antarctica where the shelves stayed stable or grew slightly. Vaughan said the regional variations were predicted by previous studies.

Holland said it was important not to confuse floating ice shelves, which can be up to 2km thick, with the much thinner sea ice.

The one metre thick layer of sea ice around Antarctica has been expanding in recent decades, which some scientists think is because of increasing polar winds, which push the ice further out.

Links :

• Climate Central : Antarctica’s Icy ‘Doorstops’ Thin; Rising Seas At Risk
• Scientific America : Antarctica's Ice Shelves Thin, Threaten Significant Sea Level Rise
• Washington Post : Antarctica’s floating ice shelves, the doorstop of the continent, are melting away
• NPR : Big Shelves Of Antarctic Ice Melting Faster Than Scientists Thought
• The Conversation : Shrinking of Antarctic ice shelves is accelerating

France SHOM update with the Marine GeoGarage

new update (17/03/2015) in the France (SHOM) layer

2 charts has been substituted since the last update (October 2014) :

7705   Abords de Mohammadia (replacing chart 6142 Abords de Mohammadia)

7800   Golfe d'Aden et approches (replacing chart 6947 Abords et Partie Est du golfe d'Aden)

All the other charts have been updated according to the new editions :

voir GAN Groupe d'Avis aux Navigateurs en ligne

Today 750 charts including sub-charts from SHOM material are displayed in the Marine GeoGarage.