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.

full screen view

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 :

• BBC : Satellites detect 'thousands' of new ocean-bottom mountains / map in 3d
• NationalGeographic : Interpolation of ocean-floor shape by satellite 
• Wired : Super-detailed interactive 3-D seafloor map
• Nature : Gravity map uncovers sea-floor surprises
• SciencesMag : Satellites reveal hidden features at the bottom of Earth's seas
• Retracking CryoSat-2, Envisat and Jason-1 radar altimetry waveforms for improved gravity field recovery

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

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

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)

IHO ENC coverage catalog

 Countries authorizing ENC publishing for webmapping onshore apps

(not for SOLAS navigation)

• IENC (Inland Electronic Navigation charts) : Inland US and Europe Waterways (fulfiling the EU INSPIRE directive requirements for viewing for spatial information in Europe).

 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 :

• NASA Earth Observatory (2012, February 24) The Aral Sea, Before the Streams Ran Dry. Accessed September 25, 2014.
• NASA Earth Observatory (2006, April 11) Aral Sea Expansion. Accessed September 25, 2014.
• NASA Earth Observatory (2000, August 25) World of Change: Shrinking Aral Sea. Accessed September 25, 2014.
• Micklin, P. (2010, September) The past, present, and future Aral Sea.Lakes & Reservoirs: Research & Management, 15 (3), 193. Accessed September 25, 2014.
• GeoGarage blog : Stranded trawlers of the Aral Sea / Fickle Aral Sea sees some recovery
• Daily Mail : Watch one of the world's biggest seas disappear: Nasa releases series of Aral Sea satellite images showing it drying up