Saturday, October 4, 2014

Nat Young's mesmerizing Tahitian wave


From HuffingtonPost

There are times when nature's elements align perfectly to give us a glimpse of what heaven might look like.
When such moments arrive for pro surfer Nat Young, we all win.
This year, the California-born surfer literally rode off into the sunset while surfing the Tahitian surf break known as Teahupoo.
The results, as seen in this video, are nothing short of mind-blowing perfection as Young glides effortlessly through the golden-hued barrel -- which actually forms twice! -- toward the island's rolling green mountains and cotton candy clouds, all while the glowing sun sinks into the horizon.
In fact, Young's ride was so perfect, he won $10,000 just for catching it on camera and submitting it to the Association of Surfing Professional's GoPro challenge.
But don't let the wave's idyllic nature fool you.
Teahupoo, which translates to "broken skulls," has an extremely shallow and jagged reef and a powerfully steep wave-shape. It's an extremely dangerous wave, saved for the bravest of souls.
Hats off to you, Young, for this deliciously daring wave.

Friday, October 3, 2014

Canada CHS 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

CHS raster charts coverage

84 charts have been updated (September 29, 2014)
    • 1312 LAC SAINT-PIERRE
    • 1313 BATISCAN AU/TO LAC SAINT-PIERRE
    • 1314 DONNACONA À/TO BATISCAN
    • 1315 QUÉBEC À/TO DONNACONA
    • 1316 PORT DE QUÉBEC
    • 1317 SAULT-AU-COCHON À/TO QUÉBEC
    • 2053 PORT HOPE HARBOUR
    • 2055 FRENCHMAN'S BAY
    • 2058 COBOURG TO/À OSHAWA
    • 2077 LAKE ONTARIO/LAC ONTARIO - WESTERN PORTION/PARTIE OUEST
    • 2203A CARLING ROCK TO/À TWIN SISTERS ISLAND
    • 2203B TWIN SISTERS ISLAND TO/À RASPBERRY ISLAND ISLAND AND/ET TONCHES ISLAND
    • 2203C ISLE OF PINES TO/À BYNG INLET
    • 2205 KILLARNEY TO/À LITTLE CURRENT
    • 2207A BAY OF ISLANDS TO/À BENJAMIN ISLANDS
    • 2207B LITTLE CURRENT
    • 2250 BRUCE MINES TO/À SUGAR ISLAND
    • 2257 CLAPPERTON ISLAND TO/À JOHN ISLAND
    • 2259 JOHN ISLAND TO / À BLIND RIVER
    • 2283A OWEN SOUND TO/À GIANTS TOMB ISLAND
    • 2283B OWEN SOUND TO/À GIANTS TOMB ISLAND
    • 2299 CLAPPERTON ISLAND TO/À MELDRUM BAY
    • 2300 LAKE SUPERIOR / LAC SUPÉRIEUR
    • 2310 CARIBOU ISLAND TO MICHIPICOTEN ISLAND
    • 2318 HERON BAY
    • 3410 SOOKE INLET TO/À PARRY BAY
    • 3440 RACE ROCKS TO/À D'ARCY ISLAND
    • 3461 JUAN DE FUCA STRAIT EASTERN PORTION/PARTIE EST
    • 3462 JUAN DE FUCA STRAIT TO/À STRAIT OF GEORGIA
    • 3724 CAAMANO SOUND AND APPROACHES / ET LES APPROCHES
    • 3726 LAREDO SOUND AND APPROACHES
    • 3741 OTTER PASSAGE TO BONILLA ISLAND
    • 3742 OTTER PASSAGE TO/À McKAY REACH
    • 3909 BRUNDIGE INLET
    • 3936 FITZ HUGH SOUND TO / À LAMA PASSAGE
    • 3939 FISHER CHANNEL TO/À SEAFORTH CHANNEL AND/ET DEAN CHANNEL
    • 3984 PRINCIPE CHANNEL - SOUTHERN PORTION/PARTIE SUD
    • 3987 KITKATLA CHANNEL AND/ET PORCHER INLET
    • 4001 GULF OF MAINE TO STRAIT OF BELLE ISLE / AU DÉTROIT DE BELLE ISLE
    • 4011 APPROACHES TO/APPROCHES À BAY OF FUNDY/BAIE DE FUNDY
    • 4016 SAINT-PIERRE TO/À ST JOHN'S
    • 4017 CAPE RACE TO / À CAPE FREELS
    • 4024 BAIE DES CHALEURS / CHALEUR BAY AUX / TO ÎLES DE LA MADELEINE
    • 4026 HAVRE-SAINT-PIERRE ET/AND CAP DES ROSIERS À/TO POINTE DES MONTS
    • 4049 GRAND BANK NORTHERN PORTION/GRAND BANC PARTIE NORD TO\À FLEMISH PASS/PAS
    • 4201 HALIFAX HARBOUR (BEDFORD BASIN)
    • 4202 HALIFAX HARBOUR POINT PLEASANT TO/À BEDFORD BASIN
    • 4266 SYDNEY HARBOUR
    • 4275 ST PETERS BAY
    • 4277 GREAT BRAS D'OR / ST. ANDREWS AND / ET ST. ANNS BAY
    • 4308 ST. PETERS BAY TO/À STRAIT OF CANSO
    • 4320 EGG ISLAND TO / À WEST IRONBOUND ISLAND
    • 4328 LUNENBURG BAY
    • 4340 GRAND MANAN
    • 4381 MAHONE BAY
    • 4384 PEARL ISLAND TO/À CAPE LA HAVE
    • 4403 EAST POINT TO/À CAPE BEAR
    • 4419 SOURIS HARBOUR AND APPROACHES / ET LES APPROCHES
    • 4421 BOUGHTON RIVER
    • 4447 POMQUET AND TRACADIE HARBOURS / HAVRES DE POMQUET ET TRACADIE
    • 4448 PORT HOOD
    • 4466 HILLSBOROUGH BAY
    • 4486 BAIE DES CHALEURS / CHALEUR BAY
    • 4622 CAPE ST MARY'S TO/À ARGENTIA HARBOUR AND/ET JUDE ISLAND
    • 4670 FORTEAU BAY
    • 4682 LARKIN POINT TO/À CAPE ANGUILLE
    • 4701 SHIP HARBOUR HEAD TO/AUX CAMP ISLANDS
    • 4827 HARE BAY TO / À FORTUNE HEAD
    • 4841 CAPE ST. MARY'S TO/À ARGENTIA
    • 4846 MOTION BAY TO/À CAPE ST FRANCIS
    • 4847 CONCEPTION BAY
    • 4850 CAPE ST FRANCIS TO / À BACCALIEU ISLAND AND / ET HEART'S CONTENT
    • 4851 TRINITY BAY - SOUTHERN PORTION / PARTIE SUD
    • 4852 SMITH SOUND AND / ET RANDOM SOUND
    • 4853 TRINITY BAY - NORTHERN PORTION / PARTIE NORD
    • 4856 BONAVISTA BAY WESTERN PORTION/PARTIE OUEST
    • 4909 BUCTOUCHE HARBOUR
    • 4913 CARAQUET HARBOUR BAIE DE SHIPPEGAN ET/AND MISCOU HARBOUR
    • 4950 ÎLES DE LA MADELEINE
    • 4956 CAP-AUX-MEULES
    • 4957 HAVRE-AUBERT
    • 5001 LABRADOR SEA/MER DU LABRADOR
    • 5031 ST LEWIS SOUND AND/ET INLET
    • 6218A KENORA RAT PORTAGE BAY
    • 6218B KENORA RAT PORTAGE BAY
    • 7220 LANCASTER SOUND EASTERN APPROACHES/APPROCHES EST
    • 7621 AMUNDSEN GULF
    • 7778 CORONATION GULF EASTERN PORTION/PARTIE EST
    • 8048 CAPE HARRISON TO/À ST MICHAEL BAY
      So 693 charts (1677 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

      New map exposes previously unseen details of seafloor

      What would the Earth look like if we could drain the oceans?
      Accessing two previously untapped streams of satellite data, scientists at Scripps Institution of Oceanography at UC San Diego and their colleagues have created a new map of the world’s seafloor, creating a much more vivid picture of the structures that make up the deepest, least-explored parts of the ocean.
      Thousands of previously uncharted mountains rising from the seafloor and new clues about the formation of the continents have emerged through the new map, which is twice as accurate as the previous version produced nearly 20 years ago

      From Scripps by Mario Aguilera

      Mysteries of the deep come alive as satellite data bring thousands of uncharted sea mountains and new clues about deep ocean structures into focus

      Accessing two previously untapped streams of satellite data, scientists at Scripps Institution of Oceanography at UC San Diego and their colleagues have created a new map of the world’s seafloor, creating a much more vivid picture of the structures that make up the deepest, least-explored parts of the ocean.


      Thousands of previously uncharted mountains rising from the seafloor and new clues about the formation of the continents have emerged through the new map, which is twice as accurate as the previous version produced nearly 20 years ago.


      Global map of marine gravity
      (image: David Sandwell)

      Developed using a scientific model that captures gravity measurements of the ocean seafloor, the new map extracts data from the European Space Agency’s (ESA) CryoSat-2 satellite, which primarily captures polar ice data but also operates continuously over the oceans, and Jason-1, NASA’s satellite that was redirected to map the gravity field during the last year of its 12-year mission.

      Marine gravity model of the North Atlantic (10 mGal contours).
      Red dots show locations of earthquakes with magnitude > 5.5 and they highlight the present-day location of the seafloor spreading ridges and transform faults.
      This gravity information shows the details of the plate tectonic history of the rifting of these continents including the subtle signatures of fracture zones that are currently buried by sediment.

       Marine gravity model of the Central Indian Ocean (10 mGal contours). Red dots show locations of earthquakes with magnitude > 5.5 and they highlight the present-day location of the seafloor spreading ridges and transform faults.
      The image is centered at the Indian Ocean Triple Junction where three major tectonic plates meet (African plate – left; Indo-Australian plate – right; Antarctic plate bottom.
      This region of the Indian Ocean is very poorly charted and includes the search area for the Malaysian flight MH370 that was lost March 8, 2014.

      Combined with existing data and drastically improved remote sensing instruments, the new map, described in the journal Science, has revealed details of thousands of undersea mountains, or seamounts, extending a kilometer or more from the ocean bottom.
      The new map also gives geophysicists new tools to investigate ocean spreading centers and little-studied remote ocean basins.
      “The kinds of things you can see very clearly now are abyssal hills, which are the most common land form on the planet,” said David Sandwell, lead scientist of the paper and a geophysics professor in the Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics (IGPP) at Scripps.

       Vertical gravity gradient (VGG) model of the Indian Ocean Triple Junction.
      The image is centered at the Indian Ocean Triple Junction where three major tectonic plates meet (African plate – left; Indo-Australian plate – right; Antarctic plate bottom.

      Vertical gravity gradient (VGG) model of the Southwest Indian Ridge.
      This is the slowest spreading ridge on the Earth and has large fracture zone signatures that record the rifting and spreading between Africa and Antarctica.

      The authors of the study say the map provides a new window into the tectonics of the deep oceans. Previously unseen features in the map include newly exposed continental connections across South America and Africa, and new evidence for seafloor spreading ridges at the Gulf of Mexico that were active 150 million years ago and are now buried by mile-thick layers of sediment.


      The high-resolution multibeam sonar bathymetry data show that the newly charted seamount is not very prominent and rises just over 600 m from its base.

      The summit of the seamount rises 1,100 meters from the 5,100-meter-deep ocean floor.
      (3D view of the SouthWest side of the seamount with 23° slopes)
      However, it's wide enough to be detected in the gravity signal.
      - courtesy of Larry Mayer,  University New Hampshire -

      “One of the most important uses of this new marine gravity field will be to improve the estimates of seafloor depth in the 80 percent of the oceans that remains uncharted or is buried beneath thick sediment,” the authors say in the report.
      “Although CryoSat-2’s primary mission is in the cryosphere, we knew as soon as we selected its orbit that it would be invaluable for marine geodesy, and this work proves the point,” said Richard Francis, a coauthor of the paper and project manager for the development of CryoSat-2 at the European Space Agency, and honorary professor in the Department of Earth Sciences at University College London.

      Interpolation of ocean-floor shape by satellite
      •  Most ocean maps are derived from satellite altimeter measurements
      • Satellites infer ocean-floor features from the shape of the sea surface
      • They detect surface height anomalies driven by variations in local gravity
      • The gravity from the extra mass of mountains makes the water pile up
      • In lower-mass regions, such as over trenches, the sea-surface will dip
      • Limited high-resolution ship data has calibrated the satellites' maps

      The new map also provides the foundation for the upcoming new version of Google’s ocean maps to fill large voids between shipboard depth profiles.
      “The team has developed and proved a powerful new tool for high-resolution exploration of regional seafloor structure and geophysical processes,” says Don Rice, program director in the National Science Foundation’s (NSF) Division of Ocean Sciences.
      “This capability will allow us to revisit unsolved questions and to pinpoint where to focus future exploratory work.”
      “The use of satellite altimeter data and Sandwell’s improved data processing technique provides improved estimates of marine gravity and bathymetry world-wide, including in remote areas,” said Joan Cleveland, Office of Naval Research (ONR) deputy director, Ocean Sensing and Systems Division. “Accurate bathymetry and identifying the location of seamounts are important to safe navigation for the U.S. Navy.”

       Depths over seamounts, including Reed Bank and Palawan, in the South China Sea are pictured

      In addition to Sandwell and Francis, coauthors of the paper include R. Dietmar Muller of the University of Sydney, Walter Smith of the NOAA Laboratory for Satellite Altimetry, and Emmanuel Garcia of Scripps.
      The study was supported by NSF, ONR, the National Geospatial-Intelligence Agency, and ConocoPhillips.

      Links :

      Thursday, October 2, 2014

      Earth's oceans get numerical ratings for overall health

      The world's oceans get a 'D' in a health report card called the Ocean Health Index.
      Still, researchers say, with all the problems facing our seas, the result was better than expected.
      (Photo : University of California Santa Barbara)

      From TechTimes by Jim Algar

      It's report card time for the world's seas, as a newly released Ocean Health Index has graded the globe's marine expanses in terms of overall health.

      The index, produced by a coalition led by scientists at the National Center for Ecological Analysis and Synthesis at the University of California, Santa Barbara and by Conservation International, covers the 15 ocean regions of the world beyond national jurisdiction -- the world's high seas.
      The University of British Columbia, the New England Aquarium and other institutions also contributed data to the index.

      The average score?
      On a typical school report card, it would be a "D" with 67 out of a possible 100, based on a "quantifiable assessment of the capacity of our oceans to deliver benefits and resources sustainably," the index's website said. (see Press Release)

       The new Ocean Health Index is designed to assess the importance of the seas to people as well as other species. Here, a man paddles over a coral reef in Bird's Head, Raja Ampat, Indonesia.
      Photograph courtesy Sterling Zumbrunn, Conservation International
      The oceans were rated on their contribution to maintaining a healthy climate, safeguarding biodiversity and providing sustainable food sources, UCSB researchers say.
      To determine the scores, the researchers looked at ecological, economic, social and political factors and combined them all in a computer model for a final grade.
      The index identified pollution, overfishing, climate change and the lack of marine protections as key problems.

      There was variation around the world, the researchers noted, with the Antarctic and the Southern Ocean both scoring above the 67 average, receiving a grade of 72.HuffingtonPost : Despite Its Remoteness, Antarctica's Health Matters
      "Antarctica and the Southern Ocean are protected by distance from many of the threats caused by human populations, such as chemicals, excessive nutrients, and pathogens and trash," noted Greg Stone, chief scientist at the Moore Center for Science and Oceans at Conservation International.

        UPI/Matthew Healey

      The improvement in scores since the previous index released in 2012 was likely due to conservation measures that have slowed the decline in ocean health seen since the beginning of the industrial era, the researchers said.
      "The score of 100 that is set as a target for each goal reflects a status that is feasible to achieve and can sustainably produce maximum benefits now and in the future," says Steve Katona, managing director for the Ocean Health Index.
      "Any score below 100 means there is room for improvement."

      Still, he said, given recent bad news of overfishing, deaths of coral reefs, pollution and climate change, the score should be seen as better than many people may have expected, he says.
      "If you come home with a paper from school, your parents aren't real happy if it's a 67, but most people expected a score for the ocean that was worse," he said.

      Links :
      • NYTimes : Introducing the Ocean Health Index
      • PSmag : Is the Global Ocean healthy? We can answer that now
      • UCSantaBarbara : Rating the Planet’s Oceans
      • National Geographic : Ocean Health Gets "D" Grade in New Global Report Card
      • HuffingtonPost : Despite Its Remoteness, Antarctica's Health Matters

      Wednesday, October 1, 2014

      Did Marco Polo "discover" America?

      "Map with Ship" has the informality of a "napkin sketch on vellum," says map expert John Hessler, suggesting its maker was not a trained cartographer.
      (Library of Congress, Geography & Map Division)

      From Smithsonian by Ariel Sabar

      For a guy who claimed to spend 17 years in China as a confidant of Kublai Khan, Marco Polo left a surprisingly skimpy paper trail.
      No Asian sources mention the footloose Italian.
      The only record of his 13th-century odyssey through the Far East is the hot air of his own Travels, which was actually an “as told to” penned by a writer of romances.
      But a set of 14 parchments, now collected and exhaustively studied for the first time, give us a raft of new stories about Polo’s journeys and something notably missing from his own account: maps.

       Marco Polo's Book of Travels mentions a voyage east of Siberia for "forty days."
      This expedition to Alaska and the West Coast is documented in this "Map-with-Ship" that was given to the Library of Congress in the 1930s by the Marcian Rossi Family.
      Gunnar Thompson has argued in support of the authenticity of this map before the Society for the History of Discoveries; and he has offered to pay for a radiocarbon test of the ancient vellum or sheepskin. (jp2 map file)

      If genuine, the maps would show that Polo recorded the shape of the Alaskan coast—and the strait separating it from Asia—four centuries before Vitus Bering, the Danish explorer long considered the first European to do so.
      Perhaps more important, they suggest Polo was aware of the New World two centuries before Columbus.

      Marco Polo visits the Great Kublaï Khan of China

      “It would mean that an Italian got knowledge of the west coast of North America or he heard about it from Arabs or Chinese,” says Benjamin B. Olshin, a historian of cartography whose book, The Mysteries of the Marco Polo Maps, is out in November from the University of Chicago Press. “There’s nothing else that matches that, if that’s true.”


      But as Olshin is first to admit, the authenticity of the ten maps and four texts is hardly settled.
      The ink remains untested, and a radiocarbon study of the parchment of one key map—the only one subjected to such analysis—dates the sheepskin vellum to the 15th or 16th century, a sign the map is at best a copy.
      Another quandary is that Polo himself wrote nothing of personal maps or of lands beyond Asia, though he did once boast: “I did not tell half of what I saw.”

      The parchments came to America in the steamer trunks of an enigmatic Italian immigrant named Marcian Rossi.
      Rossi landed on Ellis Island as a teenager in 1887 and later told a historian that the documents were passed down through patrician ancestors from an admiral to whom Polo had entrusted them.
      The mustachioed, bow-tie-fancying Rossi was a father of six who worked as a tailor in San Jose, California.
      He was also a charming, cigar-puffing raconteur, who despite little schooling wrote a sci-fi thriller, A Trip to Mars.

       Colombus Notes on Marco Polo's "Le Livre des Merveilles", latin edition

      Might Rossi have conjured a Polo fantasy, too?
      “He certainly was enough of a character,” says his great-grandson, Jeffrey Pendergraft, a Houston energy executive who is custodian of the family papers.
      But neither Pendergraft nor cartographic experts suspect Rossi of forging the maps.
      “The incredible amount of knowledge in them about a whole variety of subjects—I would be very skeptical that my great-grandfather possessed,” Pendergraft says.

      When Rossi donated the palimpsest “Map with Ship” to the Library of Congress in the 1930s, even the FBI was stumped.
      The agency’s analysis, requested by the library and signed by J. Edgar Hoover, was mum on the question of authenticity.


      One reason the parchments have languished since then is their idiosyncrasy.
      They tell of people and places absent not just from Polo’s narrative but from known history.
      And they’re an awkward fit for the era’s known map styles—Portolan sailing charts, the grids and projections of Ptolemy, and the medieval schematics known as mappae mundi.

      The parchments bear inscriptions, some cryptic, in Italian, Latin, Arabic and Chinese.
      Olshin, a professor at the University of the Arts in Philadelphia, who spent more than 13 years researching and writing his new book, is the first scholar to fully decode and translate the maps and to trace Rossi’s ancestry, with some success, back to Polo’s Venice.
      One of Olshin’s most tantalizing finds are allusions to “Fusang,” an obscure fifth-century Chinese name for a “land across the ocean” that some scholars now contend was America.

      One of many Asian junks that Yuan Chinese explorers and Marco Polo could have used in 1285
      to map America's West Coast from Alaska to Peru

      History says little about Polo’s three daughters. (He had no sons.)
      But Fantina, Bellela and Moreta have star turns here, signing their names to some of the parchments and claiming to have drawn them from their father’s “letters,” apparently after his death.
      Bellela writes of hitherto untold encounters with a Syrian navigator, a band of lance-toting women in ermine pelts and people on a peninsula “twice as far from China” who wear sealskin, live on fish and make their houses “under the earth.”

      Travels made Polo an instant celebrity after his return to Venice, both for his descriptions of faraway lands and for what his countrymen suspected was wild fabrication.
      His daughters may have plunged back into their father’s notes in hopes of securing his reputation, surmises Stanley Chojnacki, a University of North Carolina expert on gender relations in 14th-century Venice, and “to claim by reason of defending him a certain measure of respectability and status and importance themselves.”

      Links :
      • DailyMail : The incredible map that shows Marco Polo may have discovered America in the the 13th century - 200 years before Christopher Columbus
      • MarcoPoloinSeattle : Marco Polo’s New World Maps (claiming the explorer then went south to Washington state.)
      • Reading Colombus

      Tuesday, September 30, 2014

      GeoGarage B2B platform proposes ENC nautical charts viewing

      Cowes (Island of Wight), UKHO ENC overlayed on Google Maps imagery

      Cowes (Island of Wight), UKHO RNC (raster chart) overlayed on Google Maps imagery

      The GeoGarage platform serves right now images of vector ENC Electronic navigational charts as a complementary offer to the different raster nautical charts (RNC) layers for its B2B customers.

      This implementation of ENCs (worldwide catalogue of 12 618 charts at this date) allows to complete the catalog of available nautical charts (more than 9 000 raster charts) proposed by the Marine GeoGarage platform, for regions where the GeoGarage can't propose -for the moment- raster data (pending licenses with some international Hydrographic Offices).

      It can be used in combination with or as a backdrop to other geo-spatial data layers (e.g. Vessel Traffic monitoring, weather) in third-parties web or mobile B2B applications.

      Note : these ENC charts can't be used for B2B integrators who plan to use them in public applications (due to restrictions on s-63 data use)

       Hamburg harbour, BSH ENC overlayed on Google Maps imagery

      GeoGarage supports a wide variety of ENC data products :

      • s-57 data from international Hydrographic Offices with which Marine GeoGarage got some partnerships
      • s-63 encrypted data (signed specifically for the GeoGarage customer in the Primar / IC-ENC catalogues)

       Countries authorizing ENC publishing for webmapping onshore apps
      (not for SOLAS navigation)

       La Garonne river (at Langon), VNF IENC overlayed on Google Maps

      Technically,  the GeoGarage platform is developed in accordance with OGC requirements, making it the simple tool for the integration of nautical charts layer in third-parties B2B applications.

       USACE IENC (US) overlayed on Bing Maps with ArcGIS JS viewer

      The GeoGarage utilizes a Web Map Service for displaying available ENC in WMS clients such as the Javascript viewers (OpenLayers, Leflet, ArcGIS, or customized Google Maps)

       San Francisco, NOAA ENC overlayed on Google Maps imagery

      The display of the vectorial ENC vector data can be configured according the specifications and the business needs of the B2B final integrator :
      • the raster display supporting all the IHO s-52 (ECDIS) symbolization chart settings
      • extended chart object filtering possibility
      • optimizing delivery of chart across the Internet through image tile cache, for quick display of selected areas
       Singapore ENC overlayed on Google Maps imagery

      Don't hesitate to contact the GeoGarage team to get some more information about Terms of Use and pricing.

      The Aral sea loses its Eastern lobe

      acquired August 19, 2014
      Satellite images from NASA show that over the last 14 years, one of the world's largest inland bodies of water, the Aral Sea in Central Asia, has almost completely dried up and disappeared.
      NASA Earth Observatory image by Jesse Allen, using data from the Level 1 and Atmospheres Active Distribution System (LAADS).
      Caption by Kathryn Hansen.
      Instrument(s): Terra - MODIS

      acquired August 25, 2000

      From NASA 

      Summer 2014 marked another milestone for the Aral Sea, the once-extensive lake in Central Asia that has been shrinking markedly since the 1960s.
      For the first time in modern history, the eastern basin of the South Aral Sea has completely dried.

      This image pair from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite shows the sea without its eastern lobe on August 19, 2014 (top).
      Substantial changes are apparent when compared to an image from August 25, 2000 (bottom), and again when compared to the approximate location of the shoreline in 1960 (black outline).

      "This is the first time the eastern basin has completely dried in modern times," said Philip Micklin, a geographer emeritus from Western Michigan University and an Aral Sea expert.
      "And it is likely the first time it has completely dried in 600 years, since Medieval desiccation associated with diversion of Amu Darya to the Caspian Sea."

      The Aral Sea circa 1856

      In the 1950s and 1960s, the government of the former Soviet Union diverted the Amu Darya and the Syr Darya—the region's two major rivers—to irrigate farmland.
      The diversion began the lake's gradual retreat.
      By the start of the Terra series in 2000, the lake had already separated into the North (Small) Aral Sea in Kazakhstan and the South (Large) Aral Sea in Uzbekistan.
      The South Aral had further split into western and eastern lobes.

       The changes are dramatically documented in a series of images from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite.
      By 2000, when this sequence of satellite photos begins, a large portion of the sea had already been drained.
      Instead of a single large body of water, there were now two smaller ones: the Northern and Southern Aral Seas.
      The Southern Aral Sea shrunk further into two lobes connected by narrow channels at the top and bottom.
      In ensuing years, the lobes get smaller and smaller.
      A drought from 2005 to 2009 accelerated the changes, NASA says.
      Also in 2005, Kazakhstan completed a dam project aimed at shoring up water supplies in the Northern Aral Sea at the expense of the southern portion.
      The most recent photo, from August 2014, shows just a thin sliver of water remaining on its western edge.

      The eastern lobe of the South Aral nearly dried in 2009 and then saw a huge rebound in 2010.
      Water levels continued to fluctuate annually in alternately dry and wet years.

      According to Micklin, the desiccation in 2014 occurred because there has been less rain and snow in the watershed that starts in the distant Pamir Mountains; this has greatly reduced water flow on the Amu Darya.
      In addition, huge amounts of river water continue to be withdrawn for irrigation.
      The Kok-Aral Dam across the Berg Strait—a channel that connects the northern Aral Sea with the southern part—played some role, but has not been a major factor this year, he said.
      "This part of the Aral Sea is showing major year-to-year variations that are dependent on flow of Amu Darya," Micklin said.
      "I would expect this pattern to continue for some time."

      Links :


      Monday, September 29, 2014

      Flight MH370: New search images reveal seabed details


      The floor of the ocean is dotted with the remains of extinct volcanoes, known as seamounts

      From BBC by

      The team looking for missing flight MH370 has released detailed images of the seabed - revealing features such as extinct volcanoes and 1,400-metre depressions for the first time.
      The collection of data from one of the most secret parts of the world is a by-product of the search.
      Until now there were better maps of Mars than of this bit of the sea floor.

       Possibility MH370 crash area with the Marine GeoGarage (AHS chart)

      The Malaysian Airlines plane vanished without trace on 8 March with 239 people on board.
      Twenty-six countries have helped look for the Boeing 777, but nothing has ever been found.
      The aircraft was flying from the Malaysian capital, Kuala Lumpur, to Beijing.

      There are also depressions on the seabed, some as deep as 1,400 metres

      The maps will be used to guide search vehicles close to the seabed

      The team at the Australian Transport Safety Bureau (ATSB), which is leading the hunt for the plane, is using sonar to map the new "priority" search area, at the bottom of the Southern Indian Ocean.
      After that they will deploy two or three deep-sea vehicles to begin the painstaking, inch-by-inch seabed search for wreckage.
      The "priority" area is based on the only piece of hard evidence investigators have, which is a series of brief, electronic "hellos" between the Boeing and a satellite.
      It is the equivalent of your mobile phone buzzing next to a loud speaker because it is checking in with a ground station, even when you are not making a call.
      But those "hellos" don't give an exact location, just a very rough idea, so the smaller, "priority" area is still 60,000 sq km (23,200 sq miles) - an area roughly the size of Croatia.

       The new maps reveal the "priority" search area in the southern Indian Ocean

      However, the data is not designed to pick up the aircraft, as the resolution is too coarse.
      Simon Boxall from the National Oceanography Centre says that despite this, it does provide a detailed look at the seabed.
      "Those 'bumps' on the sea floor in the flat, featureless plains to the south of Broken Ridge are each bigger than Ben Nevis.
      "Five kilometres (3 miles) across and typically rising 1.5km (0.9 miles) from the sea floor. The terrain of the area around Broken Ridge makes the European Alps look like foothills," he said.
      Making sonar maps is vital to ensure the team does not crash its deep-water vehicles into ridges and volcanoes. The equipment is pulled along the sea floor by a 10km armoured cable.
      Snagging that cable could damage the kit, or even cut it free, so the maps help them avoid any obstructions.
      The deep sea search vehicles have sonar that can pick out odd lumps, cameras that can double check if that lump is wreckage or just a rock and an electronic nose that can smell aviation fuel in the water, even if it is heavily diluted.


      The operation to find flight MH370 is the most complex search in history.
      They may find clues within months.
      Or they may never find the aircraft.

      Links :

      Sunday, September 28, 2014

      Velella, "by-the-wind sailors"


      The tiny sea creatures, called "by-the-wind sailors," washed ashore in Humboldt, California (above) and other beaches along the West Coast.

      From LiveSciences by Tanya Lewis

      An invasion is afoot along beaches from Oregon to California: Millions of glassy purple, jellyfish-like sea creatures that look like sailboats have been washing ashore.
      Known as "by-the-wind sailors," they typically live in the open ocean, but when warm water and storms draw them near shore, the wind blows them onto beaches, where they die in stinking piles.
      These creatures, whose scientific name is Velella velella, aren't actually jellyfish, but hydrozoans, related to the Portuguese man-of-war.
      Yet unlike man-of-war, they don't sting humans, though authorities don't recommend touching your face or eyes after handling them.

       Velella velella is known by the names sea raft, by-the-wind sailor

       or also purple sail, little sail, or simply Velella.

      Each little sailboat, measuring about 2.75 inches (7 centimeters) long, is in fact a colony of hundreds of smaller organisms, each with a specialized function such as feeding or reproduction, researchers say.
      "They sit at the surface of the ocean and have little sails," and their movement depends on which way the wind is blowing, said Richard Brodeur, a fishery biologist at NOAA Fisheries' Newport, Oregon, research station.


      Most of the time off the coast of Oregon and California, the winds are blowing toward the South, into the open ocean, Peterson said.
      But when big storms sweep out of the southwest — like one that hit California two weeks ago — it blows these living flotillas onto the beaches, he said.
      There, they usually die, giving off a bad smell as they rot, he added.


      Tons of the nautical creatures can be found at sea, but they don't always come ashore, Brodeur told Live Science. But recently, huge numbers of them have been washing up on land.
      "This happens every few years, where they get blown onto the beaches," said Bill Peterson, an oceanographer also stationed at NOAA Fisheries' Newport lab. In 2009 or 2010, the beach had piles of the creatures 2-feet to 3-feet (60 to 90 cm) thick, and "it stunk like heaven," Peterson told Live Science.


      Velella - Planktonic Vessels
      from Parafilms

      Colonies of polyps transported by prevailing winds, velella drift at the surface of warm seas.
      Plankton Chronicles Project by Christian Sardet, CNRS / Noe Sardet and Sharif Mirshak, Parafilms

      The animals can be found all over the world, but they mostly live in tropical or subtropical waters, Peterson said.
      They like warm water, which has recently been pooling off the Oregon and California coasts, he said. When you get warm water combined with storms, that's when the creatures blow ashore.
      Peterson said these beach invasions don't happen every year, but there's nothing unusual about the one this year.