Humpback whales bubbles feeding drone views

Brazil DHN update in the Marine GeoGarage

As our public viewer is not yet available
(currently under construction, upgrading to a new webmapping technology as Google Maps v2 is officially no more supported),
this info is primarily intended to our universal mobile application users
(Marine Brazil iPhone-iPad on the Apple Store / Weather 4D Android -App-in- on the PlayStore)
and also to our B2B customers which use our nautical charts layers 
in their own webmapping applications through our GeoGarage API.

 DHN coverage

17 charts has been updated and 2 charts have been added since the last update

DHN update November 1, 2014

• 1405  PORTO DE AÇU   NEW
• 1406  PROXIMIDADES DO PORTO DE AÇU  NEW
• 701  PORTO DE MUCURIPE (Fortaleza)
• 901  PORTO DE MACEIÓ
• 906  PORTO DE SUAPE
• 920  PROXIMIDADES DO PORTO DE MACEIÓ
• 930  PROXIMIDADES DO PORTO DO RECIFE
• 1511  BARRA DO RIO DE JANEIRO
• 1512  PORTO DO RIO DE JANEIRO
• 1622  BAÍA DE SEPETIBA
• 1631  BAÍA DA ILHA GRANDE - PARTE CENTRAL
• 1636  PORTO DE ANGRA DOS REIS E PROXIMIDADES
• 1804  PORTO DE SÃO FRANCISCO DO SUL
• 1902  PROXIMIDADES DA ILHA DE SANTA CATARINA
• 23100 (INT.2124)  DO RIO DE JANEIRO À SANTOS
• 201  BARRA NORTE DO RIO AMAZONAS
• 204  DAS ILHAS PEDREIRA À ILHA DE SANTANA
• 242  DA ILHA DOS PORCOS À BAÍA DO VIEIRA GRANDE
• 243  DA ILHA ITAQUARA À ILHA DOS PORCOS

Today 444 charts (510 including sub-charts) from DHN are displayed in the Marine GeoGarage
Don't forget to visit the NtM Notices to Mariners (Avisos aos Navegantes)

Navy develops ‘GhostSwimmer’ drone that looks like a shark

The US Navy is testing a fish like robot designed to carry out stealthy, silent and secure underwater surveillance missions - from intelligence gathering to hull inspections, where its silent operation and mission endurance would provide great advantages to sailors and marines. 
(other video)

From Wired by Jordan Golson 

The American military does a lot of work in the field of biomimicry, stealing designs from nature for use in new technology.
After all, if you’re going to design a robot, where better to draw inspiration than from billions of years of evolution?
The latest result of these efforts is the GhostSwimmer: The Navy’s underwater drone designed to look and swim like a real fish, and a liability to spook the bejeezus out of any beach goer who’s familiar with Jaws.

The functions of the Ghost Swimmer, a biomimetic device modeled after the bluefin tuna, is demonstrated at the Joint Expeditionary Base Little Creek

(Edwar Guttierrez/US Navy)

The new gizmo, at five feet long and nearly 100 pounds, is about the size of an albacore tuna but looks more like a shark, at least from a distance.
It’s part of an experiment to explore the possibilities of using biomimetic, unmanned, underwater vehicles, and the Navy announced it wrapped up testing of the design last week.

The robot uses its tail for propulsion and control, like a real fish.
It can operate in water as shallow as 10 inches or dive down to 300 feet.
It can be controlled remotely via a 500-foot tether, or swim independently, periodically returning to the surface to communicate.
Complete with dorsal and pectoral fins, the robofish is stealthy too: It looks like a fish and moves like a fish, and, like other underwater vehicles, is difficult to spot even if you know to look for it.

Down the line, it could be used for intelligence, surveillance, and reconnaissance missions, when it’s not assigned to more mundane tasks like inspecting the hulls of friendly ships.
Animal lovers will be glad to hear that the GhostSwimmer could take the jobs of the bottlenose dolphins and California sea lions the Navy currently trains to spot underwater mines and recover equipment.

The GhostSwimmer joins the ranks of animal-based awesome/creepy robots like the “Cheetah” that can run at nearly 30 mph, the Stickybot that climbs like a gecko, and the cockroach-inspired iSprawl that can cover 7.5 feet per second.
And it may get a baby brother: The Department of Homeland Security has been funding development of a similar, smaller robot called the BIOSwimmer.

 This robotic tuna is the final product of a team of students from the Olin College of Engineering.

True to military form, there’s a whole suite of acronyms to go along with the new toy: The UUV (unmanned underwater vehicle) has been in testing at the JEBLC-FS (Joint Expeditionary Base Little Creek-Fort Story), and was developed by the CRIC (Chief of Naval Operations Rapid Innovation Cell) project, called Silent NEMO (actually, this one doesn’t seem to stand for anything).
It was developed by the Advanced Systems Group at Boston Engineering, a Navy contractor that specializes in the development of robotics, unmanned systems and something called “special tactical equipment”.
The company and Navy haven’t said much about when GhostSwimmer might be deployed or how much it would cost, but next time you’re at the beach and see a fin sticking out of the water, it might be a killer shark—or it might just be a Navy robot.


Links :

• DefenseUpdate : Robotic spy fish conducts underwater surveillance
• GeoGarage blog : Protecting harbors and ships with a robotic tuna fish

Grounding of the Arafenua on the Tikei atoll

Arafenua customs patrol boat on the reef

From BEA Mer

During a surveillance mission, the Arafenua customs patrol boat set sail from the island of Fatu Hiva (Marquesas archipelago) to Tikei atoll (Tuamotu archipelago) on 30 May 2014 at 22:00 and grounded there on 1 June at about 04:00 (14°56’,504 S et 144°32’,436 W on the North coast of Tikei)

 Tikei with SHOM nautical chart correctly shifted on the the GeoGarage platform

Tikei is a small coral island 2 miles long, wooded, without lagoon, uninhabited and unmarked, from northern Tuamotu in French Polynesia.
It is 345 miles from the port of Papeete in Tahiti.
It is difficult to land there because the island is surrounded on all sides by a reef which consists of a first barrier at the surface of water then a platier covered with 20 cm of water.
The tidal range is very low, about 30 cm.
The 1000 metre probe line is located approximately 0.6 miles from the reef.

Before leaving Fatu Hiva on Friday 30 May, the captain overboard gathered part of the crew to explain the mission.
At the end, it traces the road on the MaxSea PC installed in 2012 which is connected to a GPS and a Furuno radar.
Starting outside Fatu Hiva's Bay of Virgins, the road tangents the 1,000 metre sounding line in northwest Tikei.

The vessel sailed on a dark night to an uninhabited islet without any light source, making optical detection impossible.
Furthermore, overcast weather with squalls increases the watchman's difficulties and reduces the quality of the radar watch.
Other weather conditions (wind and swell) have no influence on the circumstances of the occurrence.
During the day, the optical watch would have made it possible to warn the shift manager that he was on his way to the platier.
The arrival at night can therefore be considered as a determining factor.
The weather conditions on June 4 were as forecast, 1.50 to 2 m swell.
The arrival of a swell train that generated a series of waves breaking whose height was above average is the determining factor.

The patroller has an electronic mapping equipment that works with MaxSea software.
This equipment is a ECS and not an ECDIS.
This ECS is not recognised by the IMO as a replacement for the paper charts.
The electronic chart used comes from a private publisher, it is not an ENC published by an official hydrographic service.
Consequently, electronic charting equipment can only be an aid to navigation; it cannot be the primary navigation or reference system.

 Copy of map 7347 used "from the Tuamotu Archipelago to the Southern Islands".

There is no landing map of the island.
The most accurate paper chart is the "6689 - Tuamotu Islands (western part)", the one used for the approach.
It is, seen the scale (1/595 000), unusable for navigation in the direct vicinity of Tikei.
It was based on bathymetric information collected by SHOM until 1977.
It was last updated in 2010.
The geodetic reference does not appear on this map.
According the scale (1:595 000), the thickness of the pencil line (0.3 mm) is 178.5 m.
A cartridge indicates that the chart should not be used without consulting other documents, in particular Volume 1 of the Navigator's Guide for information on charts, their accuracy and limitations.
With regard to other navigation aids (radars, GPS, depth sounder), no malfunction was reported.
The lack of a landing card is an underlying factor.

The course was plotted by the captain at sea on MaxSea to arrive in the northwest of Tikéi near the 1000 m sounding line.
It is in fact an approximate isobath (broken line).
The master on board requested to plot this route on the two paper charts (7347 and 6689).
The road passes 1 mm from the islet of Tikéi on map 6689 (less than 600 m) and the landing point is not formalized although it is the first time that Arafenua approaches Tikéi.
It appears that the rules of caution set out in the navigator's guide volume 1 and its supplementary booklet entitled "L'hydrographie, les documents nautiques, leurs imperfections et leur bon usage" were not respected.
In particular the main advice for the layout of a road so as to ward off dangers which is the "thumb rule".
As specified in the above documents, the thumb refers to both an old length (2.7cm) and the width of the browser thumb.
The guard distance from the coast of Tikéi to the scale of the larger paper chart (6689) is nearly 9 miles (36 minutes at 14 knots).
Within this distance Tikéi should only be approached with great care.
The "thumb rule" also applies to electronic maps provided that the map is used at compilation scale, i.e. the scale of the paper map used to develop the electronic map.

The ease of use of the mapping software and the illusion of precision given by the electronic map that can be zoomed at will associated with GPS have made us forget the basic rules of caution.
In particular the constructive doubt with which aids to navigation should be exploited.
The habit of sailing together, for many years and in areas known for transits of a few hours, has blunted the knowledge acquired during initial training.
The master at sea's brief elaboration of the route and the absence of remarks on the route by the various watchkeepers were a determining factor in the grounding.

During the 0100 to 0400 watch, watch leader B could not accurately determine the island's position on the radar due to rain.
Having failed to adjust the anticlutter, he focuses on tracking the course on MaxSea without using the overlay function of the second radar.
He does not master the use of this equipment installed in 2012.
The island does not appear on the MaxSea map because the zoom is set to maximum.
Watch leader B loses track of the distance between him and Tikéi until he prepares his relief. Although the optical and radar watches were severely degraded, he did not take any action while approaching Tikéi at night.
It was only about 5 minutes before the grounding that he asked to intuitively reduce the engines by 100 revolutions.
The conduct of the landing watch is inadequate.
This is a determining factor.



The grounding

The ARAFENUA grounded because the actual position of the island is 1500 m further north than that indicated on the MaxSea mapping.

 DF 48 Arafenua was deemed irrecoverable after grounding on 1 June in French Polynesia.

At the scale of the 6689 paper map used, these 1500 m represent 2.5 mm.
This shift in the island's position is a contributing factor.

Extract from the Arafenua MaxSea mapping with overprinting of the satellite image where the edge of the 'platier' appears on the 2000 m probe line

 

Import in Google Earth of the route drawn on MaxSea  

Screenshot of 'Arapo' ECDIS, with Arafenua position and radar overlay

According to SHOM information, the Tikéi atoll was the subject of geodesy work in 1948 (astronomical geodesy) and 2001 (GPS).

These geodetic measurements are consistent with the uncertainties of the astronomical measurements: the difference is 150 m (approximate value, the precise location of the astronomical geodesy station has not been found).
The paper chart 6689 (scale 1/595000), published in 1978, was based on chart 6057 (1/510000), which it replaced.

Map 6057, published in 1952, uses one minute of topography also produced by the 1948 geodetic mission.

 original geoTIFF 6689 chart overlaid on Google Earth

- showing original 1500 meters shift with satellite imagery because datum none WGS84-

Analysis of the documents shows that this minute is not consistent with the geodetic measurements, which was not identified during the preparation of the mission documents and during the cartographic work: the position of the island on the topographic minute is 1 mile further south, probably due to a transcription error during the preparation of this document.
This shift affected the chart 6057 then the current chart 6689, as well as the electronic navigation chart ENC FR266890 which were elaborated from this same paper chart.

6689 Iles Tuamotu (partie Ouest), de Tahiti à Rangiroa et Makemo

scale : 1:593,700 / pub 1978 / ed 2009/ datum : unknown -non WGS84-

  view in W4D (Android test)

ENC FR266890 (ed : 30/11/2010) scale 1:350,000

Polynésie Française - Iles Tuamotu (Western part)

The force of habit and the absence of constructive doubt in the use of navigational aids combined with a lack of vigilance in the development and monitoring of navigation led to the grounding.

Note : SHOM issued offset information for paper map 6689 "Tuamotu Islands (western part)" (Preliminary Notice 14 37-P-07), and associated ENC FR266890.

Other notes from BEA mer :

• To the software publisher MaxSea :

3 2014-R-028 : to display on the vector map a blatant warning when the user uses the zoom beyond the compilation scale.

• At SHOM :

4 2014-R-029: to propose to IHO an amendment to the standard to show on ENC maps a clear warning when the user uses the zoom beyond the compilation scale.

Links :

• HEO : thread on Arafenua grounding
• Blog Fustier :  Raster Charts… the comeback
• GeoGarage blog : Digital map error may have led to minesweeper ... / USS Guardian probe report evades key issues / Time running out for USS Guardian in Tubbataha as ...

World Magnetic Model updated

Compasses have been used for several thousand years to determine direction.

They point in the direction of magnetic force at the user’s location, and the direction it points is, more often than not, in a different direction than geographic north (toward the North Pole), a more precise direction is achieved by knowing the angle between them (magnetic declination).

However, declination changes with location and time, and a geomagnetic model is often used to correct for it.

Since the changes in geomagnetic fields are difficult to predict, timely model updates (every 5 years for the WMM) are required for navigational accuracy.

The WMM satisfies all these criteria and is therefore widely used in navigation.

Examples include, but are not limited to, ships, aircraft and submarines.

Magnetometer based attitude (roll and pitch) control is commonly used in aircraft and satellites.

From NOAA

NOAA and British Geological Survey update World Magnetic Model :
Critical changes made to ensure accurate navigation

NOAA officials announced today the World Magnetic Model (WMM), a representation of Earth’s large-scale magnetic field and an indispensable complement to GPS devices used by NATO, the United States and United Kingdom militaries, as well as civil applications ranging from mineral exploration to smartphone apps, has been updated.

 Annual rate of change of declination for 2015.0 to 2020.0 from the World Magnetic Model (WMM2015).

Red –easterly change, blue – westerly change, black – zero change.

Contour interval is 1’/year (sixtieth of a degree) up to ± 20’/year,

thereafter 5’/year, and projection is Mercator

Changes in the Earth's outer core trigger unpredictable changes in its magnetic field, an invisible force that extends from Earth's interior to where it meets a stream of charged particles emanating from the Sun.
For example, over the past few decades the North magnetic pole has been drifting toward Siberia at an irregular speed.
This migration can adversely affect the accuracy of navigation if not compensated for by an updated WMM.

Declination (magnetic variation) from the WMM2015
The WMM2015 is a large-scale representation of Earth’s magnetic field.
The blue and red lines indicate the positive and negative difference between where a compass points the compass direction and geographic North.
Green lines indicate zero degrees of declination.
(Credit: NOAA)

“We know the Earth’s magnetic field is constantly changing,” said Stephen Volz, Ph.D., assistant NOAA administrator for NOAA’s Satellite and Information Service.
“But thanks to the environmental intelligence gathered from a wide array of platforms, including satellite observations, we can make vital updates to the World Magnetic Model and ensure the most accurate navigation for commercial applications.”

 Estimated WMM2015 declination inaccuracy

without considering crustal and disturbance field contributions.

 Global distribution of the declination error provided by the WMM2015 error model

Updated every five years, the WMM, created using satellite observations of the Earth’s magnetic field, provides accurate magnetic field declination, the difference between true north and magnetic north critical for navigational safety.
Scientists continuously survey the magnetic field and can precisely map the present field and its rate of change and then extrapolate changes into the future.
WMM-corrected magnetic compass readings are not subject to ionospheric disturbances and work everywhere, including under the sea and in deep canyons.

Declination in region of North Pole at 2010. from WMM2010

Red -positive (East), blue -negative (West), black -zeroContour interval is 5° and projection is Polar Stereographic

credit : BGS NERC

"Although GPS is a great tool for navigation, it is limited in that it only provides your position. Your orientation, the direction you are facing, comes from the magnetic field," said James Friederich, a geodetic scientist at the U. S. National Geospatial-Intelligence Agency.
"Our war fighters use magnetics to orient their maps. Your smartphone camera and various apps can use the magnetic field to help determine the direction you are facing. All of these examples need the WMM to provide your proper orientation."

The WMM is the standard navigation model for the U.S. Department of Defense, North Atlantic Treaty Organization, International Hydrographic Organization and consumer electronics.
For the last 10 years, NOAA’s National Geophysical Data Center (NGDC) in Boulder, Colorado, working with the British Geological Survey in Edinburgh, Scotland, has co-developed the WMM on behalf of the U.S. National Geospatial-Intelligence Agency and the United Kingdom’s Defence Geographic Centre.
NOAA’s partner, the Cooperative Institute for Research in Environmental Studies (CIRES), contributed key science to this project.

Links :

• WBGS WMM2015 calculator  /  NOAA magnetic declination estimated value calculator 
• NOAA WMM 
• NOAA CrowdMag (allows users to collect their own magnetic field data using the magnetometers in their smartphone): Androïd / iOS