The science of tides

 

 Watching the Tides

Ocean tides rise and fall twice a day, influenced by the gravitational forces of the sun and moon.

Studying tides' rhythmic movements helps us understand both the ocean and the cosmos.

Astronomer Ben Burress explains how tides work, and visiting Crissy Field in San Francisco to see the oldest continually operating tidal gauge in the Western Hemisphere. 

From Swell Lines

Tides are the most consistent variables in our surfing lives.

The Ocean is always either receding or approaching your shoreline.

It is a constant reminder of the geometry and power of astronomical forces.

Tides erode coastlines, impact marine ecosystems and even facilitated early life leaving the sea.

Rising tides can pull swell onto a beach while dropping tides can focus wave energy to a shallow sandbar or reef.

Tides are caused by the gravitational dance between the Earth, Moon and Sun.

Gravity is a fundamental force that attracts every object to every other object.

It’s the force that brought Newton’s apple to the ground and the force that accelerates a bodysurfer down a wave face.

The more massive the object, the stronger it’s gravitational pull.

The closer two objects are, the stronger the pull of gravity between them.

This pull between objects is called a tidal force.

The action of the tides, the variation in sea levels due to the gravitational pull of the Moon and Sun on the Earth.

The Moon, Earth and Sun are freaking huge.

About 36 Moons can fit inside the Earth and 1.3 million Earths fit in the Sun.

Although much much less massive than the Sun, the Moon’s gravitation has a stronger impact on Earth because it is much closer.

The sun is 93 million miles away from the Earth while the Moon is only 240,000.

Much like an apple is pulled to the ground, the Ocean is pulled toward the Moon.

Luna’s tidal force tugs on the Earth, pulling the Ocean off some beaches for low tide and onto others for high tide.

The force also impacts the Earth’s crust and atmosphere but only fractionally compared to liquid water.

 source : NOAA

Tides are caused by two bulges formed in the Ocean.

One from the tidal force toward the Moon and the other on the opposite side of the Earth caused by inertia as our planet spins.

This is the same centrifugal force that keeps the water in the bucket when you swing it  over your head.

The bulges follow the Moon and the spinning Earth around the globe.

When a bulge passes your beach, the tide rises.

The monthly tide calendar parallels the monthly lunar phase calendar.

New Moon is the alignment of Sun, Moon, Earth.

We do not see the Moon because all the light is bouncing off the Far Side.

This formation of three bodies in a line is called syzygy and it amplifies the tidal forces on the bodies. During New and Full Moons, the alignment of the Earth, Moon and Sun creates greater tidal range. Higher highs, lower lows and more dramatic swings; this is called the spring tide.

Not named for the season, but because it “springs forth.”

 Lunar phases (L) and notice the strong spring tides near Full and New Moon (R).

As the Moon orbits the Earth, it “waxes,” growing and showing more of her face each day.

After about 14 days the alignment is Sun, Earth, Moon, with the full face of Luna reflecting light. Then Luna wanes- shrinking each day until New Moon again two weeks later. 

The rest of the tide chart flows up and down between these points with the first and third quarter Moons having the smallest tidal range.

These are neap tides.

The differences between tides from day to day and month to month is the result of astronomical motions.

Luna’s orbit around the Earth forms an oval or ellipse.

Sometimes she is closer to Earth than other times.

King tides are the highest tides of the year and exist when the Moon is closest to the Earth and in syzygy alignment with the Sun.

Ebb is the decreasing tide while flood tide is the increasing.

The moment the tide changes is called slack water. 

There is 6 hours between each high and low.

Tomorrow’s high tide will be about an hour later than today’s.

Tides vary greatly all across the globe depending on factors like geographic location, local weather/swell and shoreline geology.

The East Coast of the US is semi-diurnal.

This refers to two highs and two lows each day of roughly the same height.

The West Coast is mixed semidiurnal: two highs and two lows each day with different heights.

The Gulf of Mexico is diurnal: one high and one low each day.

Three billion years ago, the Moon was much closer to the Earth, the tides rose thousands of feet over the land and then back to sea.

Today, the greatest tidal range exists in the Bay of Fundy, Nova Scotia.

Tides are focused in and out of the bay resulting in a 50ft.+ tidal change.

The lowest tidal ranges of just a foot occur in the Mediterranean, Baltic and Caribbean Seas.

The middle of Ocean basins also experience minimal tidal changes.

Hawaii’s tides rarely change more than 2ft.

However, California’s tides exhibit much more dynamism. 

California king tides can approach 8ft. with an accompanying -2ft. low.

 Bay of Fundy of Nova Scotia: largest tidal range on Earth.

(see Tides.gc.ca for Hopewell Cape)

Tides impact waves in a variety of ways.

Surf spots that prefer certain tides are referred to as tide dependent. 

Some spots are flat until a tidal push focuses the energy on the beach.

Other spots stop breaking when the tide floods because the water becomes too deep for the waves to shoal.

As a general rule, incoming, low to high tide is preferable for many surf spots.

Low tide can create fast, hollow, plunging waves. High tide often produces slow, mushy, spilling waves.

However, many shorebreak womps prefer high tides pushing up the beach.

Changing tides can also alter the strength and direction of longshore and rip currents.

Death, taxes and tides.

The great English poet, Geoffrey Chaucer, wrote “Time and tide wait for no man.”

They are predictable and unstoppable.

Tides are the only variable in surf forecasting that are concrete and certain. 

Waveriders can feel the rhythm of the tides.

We experience the astronomical forces on a different level than the mathematicians and physicists.

 High tide pushing up the beach.

Links :

• YouTube : Bay of Fundy, NB
• NOAA : Tides turorial
• National Geographic : Tide
• Maree.info :  Annuaire des marées - France

Nature’s tiny engineers : how corals stir up their world for nutrients

 Scientists have found that corals, long believed to be passive organisms relying entirely on ocean currents to deliver nutrients, are actually quite active, engineering their environment producing strong swirls of water that draw nutrients toward the coral, while driving potentially toxic waste products away.

From BBC by Victoria Gill

Coral reefs may look static to the naked eye, but scientists have now seen "violent" activity on their surface.

Using powerful microscopes, researchers filmed tiny hairs on the surface of corals "stirring up" surrounding water.
They say that these swirls of water draw nutrients towards the coral, and may also drive away potentially toxic waste products.
The findings are published in Proceedings of the National Academy of Sciences.
Scientists from the Massachusetts Institute of Technology and the Weizmann Institute of Science (WIS) in Israel studied corals grown in a laboratory tank.

"The general thinking has been that corals are completely dependent upon ambient flow from tides and turbulence [to supply nutrients]," said Orr Shapiro from WIS.
These detailed observations overturn that idea.

Tracer particles in the water enable researchers to produce images of the flow

'Vigorous stirring'

The researchers added tiny "tracer particles" to the water, which enabled them to see and capture images of the movement and flow near the surface of the coral.
They also combined powerful microscopes with high speed cameras, capturing footage of the tiny hairs, or cilia, on the corals' surface.
The resulting slow-motion footage was magnified by up to 1,000 times.
It showed, the researchers reported, the cilia beating and "vigorously stirring a layer of water that extended up to 2mm from the coral surface".

"I was very surprised and so was the entire team," another author of the study, Prof Roman Stocker from MIT told BBC News.
"We knew that corals have cilia, but did not expect that they could produce flows that are so violent."

Such a close-up understanding of how coral reefs work could help predict how they will cope with a changing ocean environment in the face of climate change.
"An active control over the environment suggests a potential ability to cope with changing conditions," said Prof Stocker.
"Although we must be careful in drawing this conclusion, as other factors, such as increased virulence of bacterial pathogens [in warmer] conditions may well tip the balance for corals the other way."

The researcher also pointed out that the experiments could play a role in human health research.
Cilia are found inside human airways, where they help to sweep away contaminants, but these microscopic internal hairs are very difficult to study.

"It's rare that you have a situation in which you see cilia on the outside of an animal," said Prof Stocker. "
"So corals could provide a general model for understanding ciliary processes related to disease."

Coop’s Citizen Sci Scoop: fishermen, sailor, beachcomber, diver – the seas of research helpers

Commander Matthew Fontaine Maury USN painting

From Plos by Caren Cooper

Many of you have had summer fun with citizen science at the beach, intertidal zone, and ocean.
What do your efforts contribute to?
In a new chapter, Martin Thiel and colleagues tallied the contributions of citizen science to marine research.
Thiel is known for his research relying on volunteers who clean up beaches, but for this chapter they looked at over 200 studies on topics that ranged from algae to vertebrates.
About 40 of the studies were local, 122 were regional, and 65 involved larger geographic regions (28 national, 28 international, 9 global).
Most commonly projects involved surveys, transects, and opportunistic sightings.
Marine scientists often depend on non-scientists, from general public to fishermen to ship crews to beachgoers.
Thiel reviewed papers published within the past 30 years, but some of the research papers were based on decades of citizen science; one was based on over 150 years of continuous data collection.

This is not a new phenomenon. I first learned about the history of citizen science when I read about the father of Oceanography, Matthew Maury.
In this context, I felt that modern citizen science is actually quite retro, which inspired my post about Maury (below), originally at Scientific American.

My area of research, citizen science—a term applied to data collection methods that engage the public in scientific research—is not a newly invented style, either.
It’s rather retro fashion.
Public involvement in science is a time-honored tradition that is enjoying a hip resurgence as it combines with today’s sophisticated and increasingly commonplace technologies, like GPS units and smart phones.

In an earlier Guest Blog post I suggested that citizen science in the US dated as far back as 1776, with Thomas Jefferson’s vision of a nationwide weather monitoring program.
Afterward, people wrote in to tell me about their own favorites.
Though many of these, such as Henry David Thoreau or Charles Darwin, were naturalists or lay scientists rather than citizen scientists per se, two suggestions particularly intrigued me: Mathew Fontaine Maury, an American naval officer, and William Whewell, a British scholar.

Both men spearheaded citizen science in the mid-1800s with large-scale, accurate and systematic science projects.
The projects were carried out by rank amateurs, and led to discoveries that had great societal importance.
The two men differed in their nationality, vocation, and perspective on the role of science in society. Their stories illustrate that we are in an exciting era where history is indeed repeating itself.

 Matthew Fontaine Maury Statue

For today, let’s meet the American.
In 1825, Matthew Fontaine Maury was a 19-year-old when he left home and joined the U.S. Navy. Maury began his naval service as a midshipman on a frigate (the Brandywine), rose through the ranks of lieutenant, commander, and commodore, and culminated his career as Superintendent of the U.S. Naval Observatory.
Over the course of his distinguished naval career, Maury contributed to our understanding of astronomy, oceanography, and meteorology.
He carried out much of his research by crowdsourcing dispersed and historical observational records and through the establishment of a global citizen science project that continues to this day.

Matthew Fontaine Maury is the father of modern hydrography in the United States Navy.

He served as superintendent of the U.S. Naval Observatory from its founding to the start of the Civil War, when he resign to supervise maritime defenses for the Confederacy.

This chart pays tribute to his leading role in establishing the charting and scientific studies that were critical to the ascendancy of the United States as a maritime economic and military power in the nineteenth century.

From the start, Maury showed an interest in engaging the public in exploring the world.
Soon after returning from his first voyage, he became the first U.S. Naval officer to write a book on nautical science, which was later used by the Naval Academy.
Edgar Allan Poe was impressed by it, writing,

“This volume, from an officer of our Navy, and a Virginian, strong commends itself to notice…The spirit of literary improvement has been awakened among the officers of our gallant Navy. We are pleased to see that science is gaining voteries from its ranks.”

Maury’s later writings are lyrical praises of the cosmos that can make Carl Sagan’s writings appear retro. In 1849, Maury presented to the Virginia Historical Society about his work at the National Observatory, writing:

“At the dead hour of the night, when the world is hushed in sleep and all is still; when there is not a sound to be heard save the dead beat escapement of the clock, counting with hollow voice the footsteps of time in ceaseless round, I turn to the Ephemeris and find there, by calculations made years ago, that when that clock tells a certain hour, a star which I never saw will be in the field of the telescope for a moment, flit through and then disappear. The instrument is set; the moment approaches and is intently awaited—I look—the star mute with eloquence that gathers sublimity from the silence of the night, comes smiling and dancing into the field, and at the instant predicted even to the fraction of a second, it makes its transit and is gone. With emotions too deep for the organs of speech, the heart swells out with unutterable anthems; we then see that there is harmony in the heavens above; and though we cannot hear, we feel the ‘music of the spheres.’”

  Andriveau-Goujon / Matthew Fontaine Maury:  Courants De L'Atmosphere 

d'Apres Le Lt. F. Maury (source : raremaps.com)

Maury embarked in crowdsourcing data in 1842 when, as a lieutenant, he was placed in charge of the Depot of Charts and Instruments of the Navy Department.
Sailors followed a strict routine and were systematic in recording very specific observations around the clock. Ships were mobile weather stations, accumulating a standardized set of weather variables with the strictest regularity at 15 minute intervals.
As much as sailors emphasized these routines, once a voyage was completed, the logs were practically viewed as rubbish.

But when Maury saw the Navy’s stockpile of old ships logs, he quickly realized the collective information could improve navigation.
Maury developed a method to systematically extract key information from each log book.
Today, in an era of climate change, the information from old logs are valuable again.
For this reason, people across the globe transcribe old ship logs in a project called Old Weather, one of several on-line citizen science projects in Zooniverse.
Maury didn’t have the help of an online network of volunteers, but he still assembled the resulting information into the colorful publication of a “Wind and Current Chart” of the North Atlantic in 1847.

 [Matthew F. Maury. Whale Chart. Washington, D.C.: Naval Observatory, 1851. Color lithograph. Geography and Map Division, G9096s. C7 var. M3, series F (8). Source: Library of Congress.]

It was a natural progression for Maury to develop a system that streamlined his ability to continually improve navigational charts.
Maury developed standardized data forms that could function as specially formatted logs.
He sent these forms, along with instructions and up-to-date charts, to mariners.
Some data may have come from Navy ships, but the notable data were voluntary contributions from merchant vessels.
Within four years, over one thousand ships were sending reports to Maury from across the seven seas!
Maury quickly incorporated the data to make new charts of trade winds, thermal charts, whale charts, and more.
The increased speed of travel across all the oceans saved millions for ocean commerce.
Before Maury’s charts, passage from New York to San Francisco took over a year.
With the help of Maury’s full color charts, the trip could be taken in a swifter vessel and reduced to a speedy three months.

Overview of Sailing Directions coverage.

The numbers in the squares indicate the individual Planning Guide coverage areas.

Maury’s legacy continued to contemporary times in the form of Sailing Directions, a 42-volume publication by the National Geospatial-Intelligence Agency (NGA).
Maury’s brainchild ended up in the NGA, the same organization credited with gathering the intelligence that allowed the U.S. military to raid the hiding place in Pakistan of Osama Bin Laden in 2011.
Yet, because Sailing Directions is based on data contributed by cooperating merchant ships, I categorize it as citizen science.

 Maury's Wind & Current Chart . . . (Atlantic Ocean & Coast of West Africa)

source : raremaps.com

In the late 1840s, Maury urged farmers to start a similar global system of meteorological observations on land, using the telegraph to aggregate reports in one location where his office could formulate weather forecasts.
When Thomas Jefferson envisioned this, the Revolutionary War made it difficult if not impossible. For Maury, the Civil War had the same effect.

Yet Maury continued to see uses for large piles of otherwise overlooked observations.
In 1847, Maury saw a way to use historic observations to aid astronomy.
That year, European astronomers discovered Neptune.
This was the first time a planet had been found through mathematics: perturbations in the orbit of Uranus could not be mathematically resolved unless another large object beyond it was assumed to exert influence on its orbit.
The key element of a planetary discovery is the computation of its orbit, but for Neptune, the mathematical rather than strictly visual nature of the discovery meant that computation would take 50 years or more.
Maury realized that instead of waiting 50 years, he could search archived records for clues in the past 50 years.
He and an assistant found that Neptune had been seen in 1795 but misidentified as a fixed star, and this enabled immediate computation of Neptune’s orbit.

When Matthew Maury saw a problem, he used scientific observations to find a solution.
Maury’s ability to express his curiosity and delight with the natural world inspired others to join his scientific pursuits and gave them a more reliable way of understanding the world.
Sailors’ lives were full of risks because they didn’t fully understand the oceans.
To deal with the risk, they believed in omens, superstitions, and good and bad luck.
The maps Maury produced immediately dispelled some of the misunderstanding and allowed mariners to benefit from collective knowledge.

 Matthew Maury at the origin of the Marine GeoGarage baseline
Marine GeoGarage, nautical charts web & mobile platform :
"just the mapping apps for the 70% of the world that Google Maps does not cover..."
see GeoGarage blog
 

Today, the benefits of collective knowledge are helping turn citizen science into a retro fashion.
It’s growing in popularity, independently in many disciplines, and emerging under different names (Community-based Participatory Science, Participatory Action Research, Open Science, Street Science, Community Science, Crowdsourcing, and the list goes on).
An umbrella term, Public Participation in Scientific Research, now unites the field—and I’ve recently returned from a conference that brought together almost 300 people active in this field.

No matter what it’s called, people participated in Maury’s science to make their lives better, and to feel enchanted and curious through the process of discovery.
Maury could be a poster child for a time when citizen science embodied the democratization of science.
Maury’s research was by the people, and for the people.
During the same period as Maury’s work, another pioneer in citizen science was working to professionalize science and to distinguish the scientist from society.

Links :

• GeoGarage blog : The oceans are in the Cloud / Crowdsourcing ocean navigation data / Unlocking the Ocean : smart ocean planning using crowdsourced data

How the International Space Station and Automatic Identification System (AIS) saved a man lost at sea

The Vessel-ID System investigation on the International Space Station demonstrated the ability for a space-based radio receiver to track a ship’s Automatic Identification System (AIS) signal, the marine equivalent of the air traffic control system.

From Redorbit by Laura Niles

The Vessel-ID System investigation on the space station demonstrated the ability for an orbit-based radio receiver to track a ship’s Automatic Identification System (AIS) signal.

The AIS signal is the marine equivalent of the air traffic control system.

The Norwegian User Support and Operation Centre in Trondheim, Norway, receives the data for near-continuous evaluation.

The Vessel-ID System is installed on the European Space Agency’s Columbus module.

Since being turned on in 2010, Vessel-ID has been able to relay more than 400,000 ship position reports from more than 22,000 ships in a single day, greatly advancing the ship tracking ability of coast guards around the world.

This ability, coupled with multiple AIS tracking satellites launched since, is providing safer travel among the waves for thousands of ships around the globe.

The ship identification and tracking system technology already aided in orienting rescue services for a lone survivor stranded in the North Sea, giving new hope to once impossible situations.

“This brought a whole new dimension to the monitoring of ship traffic on the open oceans,” said Terje Wahl, of the Norwegian Space Centre.

“This project demonstrates that the International Space Station is not just for science and astronauts, but it really benefits mankind with down-to-Earth applications.”

AISSat-1 Real-time (RT) coverage area (1 year of data)

FFI has performed a feasibility study on space-based reception of AIS messages.

The results show a ship detection probability of near 100% for up to 1000 ships within the coverage area, and a signal power margin of 10 to 20 dB for a standard AIS receiver.
A space-based AIS receiver will cover Norwegian waters up to 15 times a day in the northern region, and more than 8 times a day in the south.

The data will include ship identity, position, speed, bearing, etc, and make it possible to track a high number of ships.
A constellation of four satellites will give global coverage approximately every hour.
To overcome saturation problems for more than 1000 ships, a study on an optimized system for global surveillance was done and presented to the International Maritime Organization.

This slightly modified AIS system can be an option for Long- Range Identification and Tracking.

Links :

• YouTube : Space Station Live: Observing Earth Winds from Space /  Space Station Live: NASA Partners With EPA for Ocean Study
• GeoGarage blog : Watch sea traffic from space : S-AIS / Space station keeps watch on world's sea traffic / Boom in satellite ship tracking
• NASA : Space Station keeps watch on World's sea traffic

UK & misc. 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 B2B customers which use our nautical charts layers in their own webmapping applications through our GeoGarage API.

Today 952 charts (1813 including sub-charts) from UKHO
are available in the 'UK & misc.' chart layer

regrouping charts for different countries :

1. UK
2. Argentina
3. Belgium
4. Netherlands
5. Croatia
6. Oman
7. Portugal
8. Spain
9. Iceland
10. South Africa
11. Malta

 3 charts have been withdrawn (1167, 2020, 3265) since the last update
and 2 charts have been added (3291, 3583)

636 charts for UK
(1167 Burry Inlet,
2020 Harbours and Anchorages in the BVI,
3265 Weligama to Little Basses Reef
withdrawn,
3583 South Atlantic Ocean, South Georgia, Cooper Sound to Drygalski Fjord
added)

24 charts for Argentina :

• 226    International Chart Series, Antarctica - South Shetlands Islands, Deception Island.
• 227    Church Point to Cape Longing including James Ross Island
• 531    Plans on the Coast of Argentina
• 552    Plans on the Coast of Argentina
• 557    Mar del Plata to Comodoro Rivadavia
• 1302    Cabo Guardian to Punta Nava
• 1331    Argentina, Approaches to Bahia Blanca
• 1332    Isla de los Estados and Estrecho de le Maire
• 1751    Puerto de Buenos Aires
• 1982B    Rio Parana - Rosario to Parana
• 2505    Approaches to the Falkland Islands
• 2517    North-Western Approaches to the Falkland Islands
• 2519    South-Western Approaches to the Falkland Islands
• 3065    Punta Piedras to Quequen
• 3066    Quequen to Rio Negro
• 3067    Rio Negro to Isla Leones
• 3106    Isla Leones to Pto San Julian
• 3213    Plans in Graham Land
• 3560    Gerlache Strait  Northern Part
• 3566    Gerlache Strait  Southern Part
• 3755    Bahia Blanca
• 4063    Bellingshausen Sea to Valdivia
• 4200    Rio de la Plata to Cabo de Hornos
• 4207    Falkland Islands to Cabo Corrientes and Northeast Georgia Rise

27 charts for Belgium & Nederlands :

• 99 Entrances to Rivers in Guyana and Suriname
• 110 Westkapelle to Stellendam and Maasvlakte
• 112 Terschellinger Gronden to Harlingen
• 120 Westerschelde - Vlissingen to Baalhoek and Gent - Terneuzen Canal
• 122 Approaches to Europoort and Hoek van Holland
• 124 Noordzeekanaal including Ijmuiden, Zaandam and Amsterdam
• 125 North Sea Netherlands - Approaches to Scheveningen and Ijmuiden
• 126 North Sea, Netherlands, Approaches to Den Helder
• 128 Westerschelde, Valkenisse to Wintam
• 207 Hoek Van Holland to Vlaardingen
• 208 Rotterdam, Nieuwe Maas and Oude Maas
• 209 Krimpen a/d Lek to Moerdijk
• 266 North Sea Offshore Charts Sheet 11
• 572 Essequibo River to Corentyn River
• 702 Nederlandse Antillen, Aruba and Curacao
• 1187 Outer Silver Pit
• 1408 North Sea, Harwich and Rotterdam to Cromer and Terschelling.
• 1412 Caribbean Sea - Nederlandse Antillen, Ports in Aruba and Curacao
• 1414 Bonaire
• 1503 Outer Dowsing to Smiths Knoll including Indefatigable Banks.
• 1504 Cromer to Orford Ness
• 1546 Zeegat van Texel and Den Helder Roads
• 1630 West Hinder and Outer Gabbard to Vlissingen and Scheveningen
• 1631 DW Routes to Ijmuiden and Texel
• 1632 DW Routes and Friesland Junction to Vlieland
• 1874 North Sea, Westerschelde, Oostende to Westkapelle
• 2047 Approaches to Anguilla

13 charts for Croatia :

• 201 Rt Kamenjak to Novigrad
• 202 Kvarner, Kvarneric and Velebitski Kanal
• 269 Ploce and Split with Adjacent Harbours, Channels and Anchorages
• 515 Zadar to Luka Mali Losinj
• 680 Dubrovnik
• 1574 Otok Glavat to Ploce and Makarska
• 1580 Otocic Veliki Skolj to Otocic Glavat
• 1996 Ports in Rijecki Zaljev
• 2711 Rogoznica to Zadar
• 2712 Otok Susac to Split
• 2719 Rt Marlera to Senj including Approaches to Rijeka
• 2773 Sibenik, Pasmanski Kanal, Luka Telascica, Sedmovrace, Rijeka Krka
• 2774 Otok Vis to Sibenik

 7 charts for Oman :

• 2853 Gulf of Oman, approaches to Sohar       
• 2854 Northern approaches to Masirah
• 3171 Southern Approaches to the Strait of Hormuz
• 3409 Plans in Iran, Oman and the United Arab Emirates
• 3511 Wudam and Approaches
• 3518 Ports and Anchorages on the North East Coast of Oman
• 3762 Oman - South East coast, Ad Duqm

125 charts for Spain & Portugal :

(1 chart added, 3291)

• 45 Gibraltar Harbour
• 73 Puerto de Huelva and Approaches
• 83 Ports on the South Coast of Portugal
• 85 Spain - south west coast, Rio Guadalquivir
• 86 Bahia de Cadiz
• 87 Cabo Finisterre to the Strait of Gibraltar
• 88 Cadiz
• 89 Cabo de Sao Vicente to Faro
• 91 Cabo de Sao Vicente to the Strait of Gibraltar
• 93 Cabo de Santa Maria to Cabo Trafalgar
• 142 Strait of Gibraltar
• 144 Mediterranean Sea, Gibraltar
• 307 Angola, Cabeca da Cobra to Cabo Ledo
• 308 Angola, Cabo Ledo to Lobito
• 309 Lobito to Ponta Grossa
• 312 Luanda to Baia dos Tigres
• 366 Arquipelago de Cabo Verde
• 469 Alicante
• 473 Approaches to Alicante
• 518 Spain East Coast, Approaches to Valencia
• 562 Mediterranean Sea, Spain - East Coast, Valencia.
• 580 Al Hoceima, Melilla and Port Nador with Approaches
• 659 Angola, Port of Soyo and Approaches
• 690 Cabo Delgado to Mikindani Bay
• 1094 Rias de Ferrol, Ares, Betanzos and La Coruna
• 1096 Ribadeo
• 1110 La Coruna and Approaches
• 1111 Punta de la Estaca de Bares to Cabo Finisterre
• 1113 Harbours on the North-West Coast of Spain
• 1117 Puerto de Ferrol
• 1118 Ria de Ferrol
• 1122 Ports on the North Coast of Spain
• 1133 Ports on the Western Part of the North Coast of Spain
• 1142 Ria de Aviles
• 1145 Spain - North Coast, Santander
• 1150 Ports on the North Coast of Spain
• 1153 Approaches to Gijon
• 1154 Spain, north coast, Gijon
• 1157 Pasaia (Pasajes) and Approaches
• 1172 Puertos de Bermeo and Mundaka
• 1173 Spain - North Coast, Bilbao
• 1174 Approaches to Bilbao
• 1180 Barcelona
• 1189 Approaches to Cartagena
• 1193 Spain - east coast, Tarragona
• 1194 Cartagena
• 1196 Approaches to Barcelona
• 1197 Plans on the West Coast of Africa
• 1215 Plans on the Coast of Angola
• 1216 Baia dos Tigres
• 1290 Cabo de San Lorenzo to Cabo Ortegal
• 1291 Santona to Gijon
• 1448 Gibraltar Bay
• 1453 Gandia
• 1455 Algeciras
• 1460 Sagunto
• 1514 Spain - East Coast, Castellon
• 1515 Ports on the East Coast of Spain
• 1589 Almeria
• 1595 Ilhas do Principe, de Sao Tome and Isla Pagalu
• 1684 Ilha da Madeira, Manchico and Canical
• 1685 Ilha de Madeira, Ponta Gorda de Sao Lourenco including the Port of Funchal
• 1689 Ports in the Arquipelago da Madeira
• 1701 Cabo de San Antonio to Vilanova I la Geltru including Islas de Ibiza and Formentera
• 1703 Mallorca and Menorca
• 1704 Punta de la Bana to Islas Medas
• 1724 Canal do Geba and Bissau
• 1726 Approaches to Canal do Geba and Rio Cacheu
• 1727 Bissau, Bolama and Approaches
• 1730 Spain - West Coast, Ria de Vigo
• 1731 Vigo
• 1732 Spain - West Coast, Ria de Pontevedra
• 1733 Spain - West Coast, Marin and Pontevedra
• 1734 Approaches to Ria de Arousa
• 1740 Livingston Island, Bond Point to Brunow Bay including Juan Carlos 1 Base and Half Moon Island
• 1755 Plans in Ria de Arousa
• 1756 Ria de Muros
• 1762 Vilagarcia de Arosa
• 1764 Ria de Arousa
• 1831 Arquipelago da Madeira
• 1847 Santa Cruz de Tenerife
• 1850 Approaches to Malaga
• 1851 Malaga
• 1854 Motril and Adra
• 1856 Approaches to Puerto de La Luz (Las Palmas)
• 1858 Approaches to Santa Cruz de Tenerife, Puerto de San Sebastian de la Gomera, Santa Cruz de la Palma and Approaches
• 1861 North Atlantic Ocean – Islas Canarias, Gran Canaria to El Hierro 
• 1862 North Atlantic Ocean – Islas Canarias, Lanzarote to Cabo Bojador  
• 1863 Islas Canarias, Puerto de los Marmoles to Puerto del Rosario  
• 1895 Ilha de Sao Miguel
• 1950 Arquipelago dos Acores
• 1956 Arquipelago dos Acores  Central Group
• 1957 Harbours in the Arquipelago Dos Acores (Central Group)
• 1959 Flores,Corvo and Santa Maria with Banco Das Formigas
• 2742 Cueta
• 2761 Menorca
• 2762 Menorca, Mahon
• 2831 Punta Salinas to Cabo de Formentor including Canal de Menorca
• 2832 Punta Salinas to Punta Beca including Isla de Cabrera
• 2834 Ibiza and Formentera
• 2932 Cabo de Sao Sebastiao to Beira
• 2934 Africa - east coast, Mozambique, Beira to Rio Zambeze
• 2935 Quelimane to Ilha Epidendron
• 3034 Approaches to Palma
• 3035 Palma
• 3220 Entrance to Rio Tejo including Baia de Cascais
• 3221 Lisboa, Paco de Arcos to Terreiro do Trigo
• 3222 Lisboa, Alcantara to Canal do Montijo
• 3224 Approaches to Sines
• 3227 Aveiro and Approaches
• 3228 Approaches to Figueira da Foz
• 3257 Viana do Castelo and Approaches
• 3258 Approaches to Leixoes and Barra do Rio Douro
• 3259 Approaches to Setubal
• 3260 Carraca to Ilha do Cavalo
• 3291 Angola, (Cabinda), Cabinda and Malongo Terminals   NEW 
• 3448 Plans in Angola
• 3578 Eastern Approaches to the Strait of Gibraltar
• 3633 Islas Sisargas to Rio Mino
• 3634 Montedor to Cabo Mondego
• 3635 Cabo Mondego to Cabo Espichel
• 3636 Cabo Espichel to Cabo de Sao Vicente
• 3764 Cabo Torinana to Punta Carreiro
• 4114 Arquipelago dos Acores to Flemish Cap
• 4115 Arquipelago dos Acores to the Arquipelago de Cabo Verde

14 charts for Iceland :

• 2733 Dyrholaey to Snaefellsjokull
• 2734 Approaches to Reykjavik
• 2735 Iceland - South West Coast, Reykjavik
• 2897 Iceland
• 2898 Vestfirdir
• 2899 Iceland, Noth Coast, Horn to Rauoinupur
• 2900 Iceland, North East Coast, Rauoinupur to Glettinganes
• 2901 Iceland, East Coast, Glettinganes to Stokksnes
• 2902 Stokksnes to Dyrholaey
• 2955 Iceland, North Coast, Akureyri
• 2956 Iceland, North Coast, Eyjafjordur
• 2937 Hlada to Glettinganes
• 2938 Reydarfjordur
• 4112 North Atlantic Ocean, Iceland to Greenland

48 charts for South Africa :

• 578    Cape Columbine to Cape Seal
• 632    Hollandsbird Island to Cape Columbine
• 643    Durban Harbour
• 665    Approaches to Zanzibar
• 1236    Saldanha Bay
• 1806    Baia dos Tigres to Conception Bay
• 1846    Table Bay Docks and Approaches
• 1922    RSA - Simon's Bay
• 2078    Port Nolloth to Island Point
• 2095    Cape St Blaize to Port S. John's
• 3211    Zanzibar Harbour
• 3793    Shixini Point to Port S Johns
• 3794    Port S Johns to Port Shepstone
• 3795    Port Shepstone to Cooper Light
• 3797    Green Point to Tongaat Bluff
• 3859    Cape Cross to Conception Bay
• 3860    Mutzel Bay to Spencer Bay
• 3861    Namibia, Approaches to Luderitz
• 3869    Hottentot Point to Chamais Bay
• 3870    Chamais Bay to Port Nolloth
• 4132    Kunene River to Sand Table Hill
• 4133    Sand Table Hill to Cape Cross
• 4136    Harbours on the West Coasts of Namibia and South Africa
• 4141    Island Point to Cape Deseada
• 4142    Saldanha Bay Harbour
• 4145    Approaches to Saldanha Bay
• 4146    Cape Columbine to Table Bay
• 4148    Approaches to Table Bay
• 4150    Republic of South Africa, South West Coast, Table Bay to Valsbaai
• 4151    Cape Deseada to Table Bay
• 4152    Republic of South Africa, South West Coast, Table Bay to Cape Agulhas
• 4153    Republic of South Africa, South Coast, Cape Agulhas to Cape St. Blaize
• 4154    Mossel Bay
• 4155    Cape St Blaize to Cape St Francis
• 4156    South Africa, Cape St Francis to Great Fish Point
• 4157    South Africa, Approaches to Port Elizabeth
• 4158    Republic of South Africa - South Coast, Plans in Algoa Bay.
• 4159    Great Fish Point to Mbashe Point
• 4160    Ngqura Harbour
• 4162    Approaches to East London
• 4163    Republic of South Africa, South East Coast, Mbashe Point to Port Shepstone
• 4170    Approaches to Durban
• 4171    Republic of South Africa – South East Coast, Port Shepstone to Tugela River
• 4172    Tugela River to Ponta do Ouro
• 4173    Approaches to Richards Bay
• 4174    Richards Bay Harbour
• 4205    Agulhas Plateau to Discovery Seamounts
• 4700    Port Elizabeth to Mauritius 

5 charts for Malta :


• 36 Marsaxlokk
• 177 Valletta Harbours
• 211 Plans in the Maltese Islands
• 2537 Ghawdex (Gozo), Kemmuna (Comino) and the Northern Part of Malta
• 2538 Malta


55 international charts from NGA

•  3 Chagos Archipelago
• 82 Outer Approaches to Port Sudan
• 100 Raas Caseyr to Suqutra
• 255 Eastern Approaches to Jamaica
• 256 Western Approaches to Jamaica
• 260 Pedro Bank to the South Coast of Jamaica
• 333 Offshore Installations in the Gulf of Suez
• 334 North Atlantic Ocean, Bermuda
• 386 Yadua Island to Yaqaga Island
• 390 Bahamas, Grand Bahama Island, Approaches to Freeport
• 398 Grand Bahama Island, Freeport Roads, Freeport Harbour
• 457 Portland Bight
• 462 The Cayman Islands
• 486 Jamaica and the Pedro Bank
• 501 South East Approaches to Trinidad
• 700 Maiana to Marakei
• 868 Eastern and Western Approaches to The Narrows including Murray's Anchorage
• 920 Chagos Archipelago, Diego Garcia
• 928 Sulu Archipelago
• 959 Colson Point to Belize City including Lighthouse Reef and Turneffe Islands
• 1043 Saint Lucia to Grenada and Barbados
• 1225 Gulf of Campeche
• 1265 Approaches to Shatt Al 'Arab or Arvand Rud, Khawr Al Amaya and Khawr Al Kafka
• 1450 Turks and Caicos Islands, Turks Island Passage and Mouchoir Passage
• 1638 Plans in Northern Vanuatu
• 2009 Sheet 2  From 23 deg 40 min North Latitude to Old Bahama Channel
• 2065 Northern Antigua
• 2133 Approaches to Suez Bay (Bahr el Qulzum)
• 2373 Bahr el Qulzum (Suez Bay) to Ras Sheratib
• 2374 Ra's Sharatib to Juzur Ashrafi
• 2658 Outer Approaches to Mina` al Jeddah (Jiddah)
• 2837 Strait of Hormuz to Qatar
• 2847 Qatar to Shatt al `Arab
• 3043 Red Sea, Ports on the coast of Egypt.
• 3102 Takoradi and Sekondi Bays
• 3175 Jazirat al Hamra' to Dubai (Dubayy) and Jazireh-ye Sirri
• 3179 UAE and Qatar, Jazirat Das to Ar Ru' Ays
• 3310 Africa - east coast, Mafia Island to Pemba Island
• 3361 Wasin Island to Malindi
• 3432 Saltpond to Tema
• 3493 Red Sea - Sudan, Bashayer Oil Terminals and Approaches.
• 3519 Southern Approaches to Masirah
• 3520 Khawr Kalba and Dawhat Diba to Gahha Shoal
• 3522 Approaches to Masqat and Mina' al Fahl
• 3530 Approaches to Berbera
• 3709 Gulf of Oman, United Arab Emirates, Port of Fujairah (Fujayrah) and Offshore Terminals.
• 3723 Gulf of Oman, United Arab Emirates, Approaches to Khawr Fakkan and Fujairah (Fujayrah).
• 3785 Mina' Raysut to Al Masirah
• 3907 Bahama Islands and Hispaniola, Passages between Mayaguana Island and Turks and Caicos Islands.
• 3908 Passages between Turks and Caicos Islands and Dominican Republic
• 3910 Little Bahama Bank including North West Providence Channel
• 3912 Bahamas, North East Providence Channel and Tongue of the Ocean
• 3913 Bahamas, Crooked Island Passage and Exuma Sound
• 3914 Turks and Caicos Islands and Bahamas, Caicos Passage and Mayaguana Passage
• 3951 Sir Bani Yas to Khawr al `Udayd

Don't forget to visit the UKHO Notices to Mariners : NTM for 2014


UKHO chart catalogue availability


So today, for a cost of 9.9 € / month ('Premium Charts' subscription), you can have access to 2588 additional updated charts (4332 including sub-charts) coming from 3 international Hydrographic Services (UKHO, CHS, AHS and France).