Oman Sail : Mod70 vs GC32

Mod70 ⚔ GC32 ● Oman Sail ● Marseille (France) ✔

Latitude & Longitude: 43º 19’ 94" N ● 5º 19' 79" E | Channel: VHF 16 

Links :

• Vimeo :  MOD 70 Phaedo3 doing 35 knots during a World Record-breaking sail from Cowes to Dinard

Image of the week : Great Exuma Island, Bahamas from space

Amazing shot of Great Exuma Island, Bahamas from Space.

Image was taken by an astronaut of the Expedition 44 crew
(acquired July 15, 2015)

From NASA

An astronaut aboard the International Space Station took this photograph of small island cays in the Bahamas and the prominent tidal channels cutting between them.
For astronauts, this is one of the most recognizable points on the planet.

 zoom on Green Turtle Cut (WLP nautical charts) in the GeoGarage platform

The string of cays—stretching 14.24 kilometers (8.9 miles) in this image—extends west from Great Exuma Island (just outside the image to the right).
Exuma is known for being remote from the bigger islands of The Bahamas, and it is rich with privately owned cays and with real pirate history (including Captain Kidd).

 Great Exuma Islands in the GeoGarage platform

Small tidal changes on the banks cause great quantities of water to flow daily through the narrow channels between the cays, first in one direction and then the other.
The darker blue sections are the deepest parts of the channels, where the water flow has cut through the rock ridge that makes the line of cays.
The surrounding water is shallow (less than 25 meters, or 80 feet) and appears light blue.
Thanks to the astronaut’s steady hands in controlling a long lens in weightlessness, this photograph is detailed enough to show a single aircraft and its twin condensation trails.

Links :

• GeoGarage blog : Image of the week : the Eleuthera Island, Bahamas / Image of the week : Bahamas blue / Image of the week : Dunes of the Great Bahama Bank / Tidal flats and channels on Long Island, Bahamas / San Salvador island, a Bahamas kitesurf paradise

We can solve the ocean plastic problem

A seal trapped in plastic debris

Photo Ewan Edwards/The Clipperton project

From HuffingtonPost by Andreas Merkl (Ocean Conservancy)

Today, Ocean Conservancy released a major report: Stemming the Tide-Land-based strategies for a plastic-free ocean.
We think it's a big deal.
It squarely addresses one of our biggest worries: the avalanche of plastic that cascades into the ocean every year.

It's getting really bad.
Practically every kind of animal, from plankton to whales, is now contaminated by plastic.
It's in the birds, in the turtles, in the fish.
At the current rate, we could have 1 ton of plastics for every 3 tons of fish by 2015.

This is nobody's plan.
It's not the plan of the plastics industry, it's not the plan of the consumer goods industry and it's certainly not the plan for those of us who love and need the ocean.
Nobody wants this.

The problem is born on land.
Most of the plastic originates in rapidly industrializing countries whose waste management infrastructure is lagging behind.
This is a typical phase of development that all countries go through.
The problem is simply that the enormous utility of plastic, combined with the explosive economic growth of Asia and Africa, combine to yield an enormous flow of unmanaged plastic waste into the ocean.

The majority of plastic waste ending up in dumps and in waterways is composed of thin films used in grocery bags and food packaging.
This type of material is very low value after it is discarded and there is little economic incentive to pick it up.
Blown or washed into the ocean, it breaks apart, and becomes the "microplastic" that is so easily mistaken by animals for tasty zooplankton.
These microplastics are ubiquitous, found everywhere from the equator to the poles, and it is a real and rapidly growing problem.
By comparison, the famous ocean gyres, or "garbage patches", which are considered to be the most concentrated areas of plastic in the ocean, contain only a small percentage (< 3 percent) of all plastics entering the ocean.

So what to do?
We are fortunate, in a sense, that the plastic flow into the ocean is quite concentrated.
Only five Asian countries account for the majority of the flow.
Within these countries, there are a limited number of cities, rivers and watershed that really matter.
We know where we need to go.

A "fish market" in Hong Kong. Most plastic pollution in the ocean originates from five Asian nations.

In developing regions, the most troublesome plastic waste tends to be in the form of low-value bags and thin films.

photo : Fedor Selivanov

In these places, we need to first concentrate on the basics: the safe collection, transportation and storage of plastic waste.
By optimizing the waste hauling system, increasing collection rates to 80 percent and advancing waste treatment and conversion technologies in these five countries alone, we could cut the flow of plastic into the ocean by 45% by 2025.

Stemming the Tide lays out in detail how the various elements of the solution have to come together, what they cost and who needs to be involved.
This is clearly a solvable problem, but it will require the cooperation of many groups: industry, cities, national governments, multi-lateral organizations, banks, NGOs.
Together, we need to create the conditions that make it possible for investors and entrepreneurs to invest in integrated waste management solutions.

This is a classic example of a global problem with local solutions.
The good news is that the global community is becoming very concerned about the ocean plastic problem.
We can concentrate global expertise and resources on local problems, greatly accelerating the rate at which the fundamental waste management infrastructure is built.

Ocean Conservancy created the Trash Free Seas Alliance® (Alliance) specifically to focus these global resources on the right local problems.
It consists of NGOs, corporations and scientists that have come together to create pragmatic, real-world solutions focused on the measurable reduction of ocean plastics.
Stemming the Tide is a signature initiative of the Alliance with support from the American Chemistry Council, The Coca-Cola Company, the Dow Chemical Company, REDISA and WWF, and was advised by a broad set of experts from the industrial, finance and waste management realms.

For the Alliance, this report is only the end of the beginning: it is the start of a global effort to turbo-charge the development of ocean-smart waste management infrastructure in the places that really matter.

Links :

• The Guardian : By 2025, our seas may be filled with one ton of plastic for every three tons of fish
• Wired : Adding more plastic to our oceans could clean them up
• BBC : Plastic oceans: What do we know?

NGA to update Bowditch, seeks public input

The American Pratical Navigator
from Nathaniel Bowditch, the founder of modern maritime navigation.

From NGA by Carling Uhler 

Nathaniel Bowditch’s “The American Practical Navigator,” often simply called “Bowditch” and regarded by mariners as the premier navigational reference, is due for an update, and the National Geospatial-Intelligence Agency wants input from mariners the world over.

The first edition of “The American Practical Navigator” was a revision of “The New Practical Navigator,” the most popular navigational text of the 1700s.
Bowditch, a famous mariner and mathematician, worked with other experts of that era to revise and update the original publication and published it in 1802.

The U.S. Naval Observatory copy of the first edition "Bowditch" has the imprint "Printed at Newburyport, (Mass.) 1802, by Edmund M. Blunt, (Proprietor) For Brown & Stansbury, New York."

The manuscript signature of the original owner appears to be James "Horvey"or "Horry".

On the leaf facing the back cover, it has in manuscript "Bought by James Ho--- New York July 12th AD, 1804".

On the verso of this leaf in manuscript is "Sailed from New York for Spain June 1805."

A more recent bookplate in the front of the book states "Navigation Library of George W. Mixter". George Webber Mixter (1876-1947) wrote several books on navigation including "Primer of Navigation" which was published in several editions.

There is no record of when this book first came to the Naval Observatory Library.

The Library owns most of the later editions of Bowditch up to the present time.
Bowditch (1773-1838) was still alive when the U. S. Navy's Depot of Charts and Instruments, forerunner of the U. S. Naval Observatory, was founded in 1830.

NGA and its predecessor organizations have been responsible for reviewing the publication and ensuring it meets the demands of the modern mariner since the 19th century.
The U.S. government purchased the rights to the book in 1867 for $25,000.
The U.S. Navy Hydrographic Office, an NGA predecessor, assumed responsibility for updating the publication in 1868, and it has been regularly updated ever since.
Now in its ninth edition, the publication is freely available for download from NGA.

Chart of the Atlantic Ocean (Bowditch)

To keep pace with the rapidly changing world of navigation, each edition has included revisions to dated material, addition or deletion of new and antiquated methods, corrections to current publications, and further updates to maritime fundamentals, piloting, electronic navigation, electronic and celestial navigation, navigational mathematics, and navigational safety measures.
Some past updates have included deleting obsolete LORAN information and adding bottom contour navigation and digital nautical charting techniques.

Chart of the harbours of Salem, Marblehead, Beverly, and Manchester :

from a survey taken in the years 1804 (Author: Bowditch, Nathaniel )

Collecting and publishing the most updated techniques, information, methods and data ensures “The American Practical Navigator” remains the reference resource for modern, practical marine navigation.
"For the past two centuries, Bowditch has provided each new generation of sailors the theory and science behind the art of modern marine navigation,” said Gerard Clifford, NGA Maritime Safety Office.

The deadline for users to insure their comments and feedback are considered for the new edition is June 30, 2016.
The next edition of Bowditch is expected to be published and released by NGA in 2017.

To submit contributions and feedback for the next edition of Bowditch, please visit the NGA Bowditch survey website, download the survey files, and send an email to Bowditch2017@nga.mil.
Contributions may also be emailed directly to Bowditch2017@nga.mil.

Why some scientists are worried about a surprisingly cold ‘blob’ in the North Atlantic Ocean

January–August 2015 Blended Land and Sea Surface Temperature Percentiles. (NOAA)

From TheWashingtonPost

It is, for our home planet, an extremely warm year.
Indeed, last week we learned from the National Oceanic and Atmospheric Administration that the first eight months of 2015 were the hottest such stretch yet recorded for the globe’s surface land and oceans, based on temperature records going back to 1880.
It’s just the latest evidence that we are, indeed, on course for a record-breaking warm year in 2015.

Yet, if you look closely, there’s one part of the planet that is bucking the trend. In the North Atlantic Ocean south of Greenland and Iceland, the ocean surface has seen very cold temperatures for the past eight months:
What’s up with that?
First of all, it’s no error. I checked with Deke Arndt, chief of the climate monitoring branch at NOAA’s National Centers for Environmental Information, who confirmed what the map above suggests — some parts of the North Atlantic Ocean saw record cold in the past eight months.
As Arndt put it by email:

For the grid boxes in darkest blue, they had their coldest Jan-Aug on record, and in order for a grid box to be “eligible” for that map, it needs at least 80 years of Jan-Aug values on the record.

Those grid boxes encompass the region from “20W to 40W and from 55N to 60N,” Arndt explained.
And there’s not much reason to doubt the measurements — the region is very well sampled.
“It’s pretty densely populated by buoys, and at least parts of that region are really active shipping lanes, so there’s quite a lot of observations in the area,” Arndt said.
“So I think it’s pretty robust analysis.”
Thus, the record seems to be a meaningful one — and there is a much larger surrounding area that, although not absolutely the coldest it has been on record, is also unusually cold.
At this point, it’s time to ask what the heck is going on here.
And while there may not yet be any scientific consensus on the matter, at least some scientists suspect that the cooling seen in these maps is no fluke but, rather, part of a process that has been long feared by climate researchers — the slowing of Atlantic Ocean circulation.
In March, several top climate scientists, including Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research and Michael Mann of Penn State, published a paper in Nature Climate Change suggesting that the gigantic ocean current known as the Atlantic Meridional Overturning Circulation, or AMOC, is weakening.
It’s sometimes confused with the “Gulf Stream,” but, in fact, that’s just a southern branch of it.
[Global warming is now slowing down the circulation of the oceans — with potentially dire consequences]

The current is driven by differences in the temperature and salinity of ocean water (for a more thorough explanation, see here).
In essence, cold salty water in the North Atlantic sinks because it is more dense, and warmer water from farther south moves northward to take its place, carrying tremendous heat energy along the way.
But a large injection of cold, fresh water can, theoretically, mess it all up — preventing the sinking that would otherwise occur and, thus, weakening the circulation.
In the Nature Climate Change paper, the researchers suggested that this source of freshwater is the melting of Greenland, which is now losing more than a hundred billion tons of ice each year.

Scientists have a theory about why the planet is going through a record warm stretch
except for this area near Greenland.
(Gillian Brockell/The Washington Post-)

I asked Mann and Rahmstorf to comment on the blue spot on the map above by e-mail. Here’s what Mann had to say:

I was formerly somewhat skeptical about the notion that the ocean “conveyor belt” circulation pattern could weaken abruptly in response to global warming. Yet this now appears to be underway, as we showed in a recent article, and as we now appear to be witnessing before our very eyes in the form of an anomalous blob of cold water in the sup-polar North Atlantic.

Rahmstorf also commented as follows:

The fact that a record-hot planet Earth coincides with a record-cold northern Atlantic is quite stunning. There is strong evidence — not just from our study — that this is a consequence of the long-term decline of the Gulf Stream System, i.e. the Atlantic ocean’s overturning circulation AMOC, in response to global warming.

I also asked Rahmstorf whether, if his thinking is right, we should expect this cold patch to become a permanent feature of temperature maps, even as the world continues to warm.

His answer was complex, but not anything that gives you much reassurance:

The short term variations will at some point also go the other way again, so I don’t expect the subpolar Atlantic to remain at record cold permanently. But I do expect the AMOC to decline further in the coming decades. The accelerated melting of the Greenland ice sheet will continue to contribute to this decline by diluting the ocean waters.

Granted, it’s not clear that all climate scientists agree with this interpretation of what’s happening in the North Atlantic — but clearly some important ones do, and they have published their conclusions in an influential journal.

The longer the situation continues, the more it is likely to attract attention.

But it has already been around for a while.

“It’s been really persistent over the last year and a half or so,” NOAA’s Arndt says.

Indeed, I spoke with Rahmstorf previously about the cold patch in the North Atlantic in March, when his study came out — and when a NOAA temperature chart for December 2014 through February 2015 also showed record cold in this area.

As Rahmstorf wrote back then, “The North Atlantic between Newfoundland and Ireland is practically the only region of the world that has defied global warming and even cooled.”

Since then, the trend appears to have only continued.

So in sum, if Mann and Rahmstorf are right, a slowing of Atlantic Ocean circulation could be beginning, and even leaving a temperature signature for all to see.

This won’t lead to anything remotely like The Day After Tomorrow (which was indeed based — quite loosely — on precisely this climate scenario).

But if the trend continues, there could be many consequences, including rising seas for the U.S. East Coast and, possibly, a difference in temperature overall in the North Atlantic and Europe.

So on future climate maps, even as we rack up more hot months and years, we’d better watch the North Atlantic closely.