7 nautical raster charts updated
see GeoGarage News
Wednesday, January 13, 2016
Satellite images are source for first-of-its-kind charts of Alaska's Yukon River
New depths are overlaid on an existing Yukon River electronic navigational chart,
demonstrating the river's changing shoreline.
From NOAA
Coast Survey has issued provisional charts for barge operators and others traversing Alaska's challenging Yukon River, relying solely on satellite images to create the electronic navigational charts that only display shoreline and shoals (shallow areas).
The ENCs, which display no depth soundings, will give the mariners annually updated information to help their navigation along the changeable river.
During a virtual meeting on January 6 with barge operators who requested NOAA's charting assistance, Andrew Kampia, the cartographer in charge of the project explained, “You may hear me refer to them as an experiment because we have not created or released a navigational product like this before.”
“The Yukon was literally uncharted,” Kampia told the group. “After some analysis and brainstorming, we decided to create a prototype ENC using only satellite data. This is unprecedented.”
Yukon River with Google imagery (Terrametrics provider)
overlayed with the GeoGarage RNC platform
Yukon River with Google Maps
overlayed with the GeoGarage RNC platform
Coast Survey is not able to provide contemporary surveys to acquire data for charting the length of the river, as funding, survey vessel availability, remoteness, and small windows of opportunity to survey are major obstacles.
Satellite-derived bathymetry from two navigation seasons between July 2014 and October 2015 helps to fill the void of contemporary data for Western Alaska.
The charts will help to address the concerns of the local barge industry that supplies goods and services to western Alaska and who have had to deal with a lack of data inshore of the 12-foot contour.
(The average draft of vessels transiting up river for village deliveries is four to six feet.)
The new Yukon River provisional ENCs US4AK98M, US4AK99M, and US4AK00M offer 1:90,000 scale coverage that spans the entrance to the Yukon River, including Apoon Pass to Kotlik, and continues east to Russian Mission.
Satellite-derived bathymetry uses satellite images and histograms and performs some logarithmic calculations that can sometimes estimate depths in relatively shallow areas.
Or, as in the case of the Yukon, satellite-derived bathymetry can estimate shoals, which are displayed on the Yukon ENCs as obstruction areas.
Unlike traditional hydrography, however, satellite-derived bathymetry doesn’t provide exact depth measurements or tidal data at the time the satellite imagery was taken.
“Shoreline depictions are derived from automated processing of satellite imagery,” Kampia said.
“We felt pretty confident in the position of the shoreline, but it is below our customary standards, so we added notes to the ENCs.”
Entrance of Yukon River with Google imagery (Terrametrics provider)
overlayed with the GeoGarage RNC platform
Entrance of Yukon River with Google Maps
overlayed with the GeoGarage RNC platform
Coast Survey has provided two special notes for the Yukon River ENCs:
WARNING PROVISIONAL ENCSince the river is in a constant state of change, Coast Survey will use satellite images after the spring thaws to make annual updates.
This ENC was constructed using the best data available. All or much of the shoreline, depths and shoals within this ENC are below customary quality, are not corrected for tides, nor based on a known sounding datum. All or much of the charted detail is highly changeable. Navigators should use this ENC with extreme caution.
SATELLITE DERIVED DEPTHS
Shoreline, depths, and obstruction areas within the area of this ENC are derived from satellite imagery from 2015. Their vertical accuracy is typically ± 2m. Uncharted dangers may exist.
Late this spring, a satellite-derived bathymetry analyst will examine the first satellite images after the Yukon thaws and is navigable.
The Landsat 8 images are available every 16 days as the satellite makes it trip around the globe, so the first usable images may not be available until May or June.
After turning the images into shoreline and bathymetric updates, updated ENCs will be issued in early July – or earlier if possible.
“We would like to routinize and improve this process over the coming years based on our analyses,” Kampia said.
“We hope to build on these successes and use these solutions in areas other than the Yukon, where traditional surveys aren’t able to provide the charts that navigators need.”
The Office of Coast Survey recently issued the revised U.S. Arctic Nautical Charting Plan, but agency officials stress that it is a “living document,” needing adjustments as priorities change.
Hydrographic and cartographic experts will travel to Alaska in March to ask the state’s maritime industry for input that will help future surveying and charting activities for the State.
Links :
- GeoGarage blog : Avoiding rock bottom: How Landsat aids nautical charting / Keeping false pass true / Finding hidden shoals on the North Slope
Revealed: how giant icebergs breathe life into remote oceans
Iceberg B-15T still adrift
Giant icebergs leave surprising green plumes of carbon sequestration in their wakes
Giant icebergs leave surprising green plumes of carbon sequestration in their wakes
From The Conversation by Grant Bigg
As giant icebergs bob across the open seas they leave behind a trail of nutrient-rich meltwater, sparking new life in the world’s remotest and least hospitable oceans.
This in turn means more carbon is taken from the atmosphere and stored below the waves.
Massive icebergs may be a symptom of climate change – but they can also help keep it in check.
“Giant” icebergs are technically those at least 18km in length.
At any one time several dozen are afloat in the Southern Ocean, and individually they can survive for up to a decade.
They make up roughly half of the ice discharged from Antarctica, so around 1000km3 per year – equivalent to the annual flow of the Congo River.
However these icebergs come in fits and starts.
Some years hardly any break off, whereas five of the biggest icebergs recorded in the satellite era broke off into the Southern Ocean during 1999-2003.
So a big iceberg year can have a huge impact.
In fact, during previous ice ages huge “iceberg armadas” from Northern Hemisphere ice sheets are believed to have redirected the Gulf Stream – albeit thanks to melting on a slightly larger scale.
It’s clear then that meltwater from giant icebergs can directly impact circulation of the Southern Ocean, and the climate above it.
However, in a recent paper in Nature Geoscience, colleagues at the University of Sheffield and I have shown there is also a significant impact on the carbon sink, and hence the rate of exchange of CO2 between the ocean and atmosphere.
Antarctica's giant icebergs are helping fight climate change
Here’s how it works: as Antarctic ice sheets slowly slide towards the ocean they bump along the continent’s bedrock, picking up iron and other nutrients which become imprisoned within the ice.
When icebergs melt they release these chemicals into the sea.
As icebergs are essentially freshwater, their water is buoyant and ascends to the ocean surface, where the iron and nutrients are utilised by phytoplankton – tiny plant-like organisms at the bottom of the marine food web.
This makes a big difference in the Southern Ocean, where limited dissolved iron – important for cell growth – restricts productivity despite an abundance of nitrate.
Melting icebergs release iron in a bio-available form, so encourage phytoplankton growth, photosynthesis, and the draw-down of atmospheric CO2.
Chlorophyll – a direct product of
phytoplankton photosynthesis –
shows life blossoming for hundreds of
kilometres around this giant iceberg.
Giant icebergs are especially important as we found the increase in productivity from their meltwater could be as much as a factor of ten above background levels, and extend hundreds of kilometres away from the melting iceberg, both upstream and downstream.
At fixed points, the effect could last for up to a month after passage of an iceberg.
This is a far larger impact on the surrounding ocean than the limited previous observational studies had found, and could provide as much as 10-20% of the net carbon export into the deep waters of the Southern Ocean.
Giant icebergs could hold back global warming
We’ve only accurately tracked giant icebergs since the 1980s so it’s difficult to know exactly what the future holds.
However, the increasing amounts of ice discharged from Antarctica in recent decades, combined with likely acceleration of change under global warming, suggests we’ll see more giant icebergs in future. If this were so, the enhanced productivity of the Southern Ocean, taking more CO2 from the atmosphere, will act as a small check on global warming.
What of the Arctic?
Icebergs are abundant in parts of the northern oceans, as the Titanic tragedy showed.
However, those calved from Greenland are only very rarely more than a kilometre or so long, and are almost never “giants".
The North Atlantic also has plenty of iron, mostly thanks to Saharan dust carried there in the atmosphere.
The Arctic and North Atlantic are therefore missing key ingredients for a strong biological response to iceberg meltwater.
However, large amounts of freshwater entering the North Atlantic could affect the meridional overturning circulation, a current which sends the Gulf Stream northwards along the surface while cooler, deeper water moves southwards.
More icebergs from Greenland, or further ice melting due to global warming, may help slow this current and check climate change.
Fortunately, the Northern Hemisphere no longer has the large ice sheets with a history of instability that could cause this sort of “Day After Tomorrow” scenario.
So if any giant icebergs are going to help slow climate change they will likely come from Antarctica, one of global warming’s most symbolic places.
Links :
Tuesday, January 12, 2016
Inmarsat’s maritime vision
The maritime industry is changing.
Watch our short video to
hear about Inmarsat’s maritime vision in supporting the data revolution
and setting a new standard in communications at sea.
From Maritime Executive by Wendy Laursen
Early this month, Inmarsat confirmed that global commercial service introduction has been achieved for its new Global Xpress (GX) constellation.
The constellation consists of three Ka-band, high-speed mobile broadband communications satellites.
GX is the first high-speed broadband network to span the world, and Inmarsat says that its maritime functionality, Fleet Xpress, will make video a viable proposition for remote assistance and diagnostics and will enable advanced applications such as telemedicine and video surveillance.
But the potential for very high availability has many ship management and safety applications and could ultimately include the potential for the safe deployment of unmanned vessels.
Purposely designed for mobility, the new GX system will provide a continuous, consistent service as traffic is handed seamlessly across each spot beam and from one satellite to another.
Global Xpress operates in the Ka-band, but, combined with the Inmarsat L-band network it is anticipated to deliver 99.9 percent overall network availability.
In announcing the launch of the company’s third GX satellite last year, Rupert Pearce, CEO of Inmarsat, said: “We have been working towards this day ever since we announced plans to create the Global Xpress constellation in 2010…
Global Xpress will deliver broadband speeds that are an order of magnitude faster than our fourth generation (I-4) constellation, to customers on the move on land, at sea and in the air, globally.
“As such, the GX fleet will offer a host of new opportunities for both our existing and new customers to significantly enhance their connectivity capabilities and to deploy bandwidth-hungry applications and solutions efficiently and effectively, even in the remotest and most inaccessible parts of the world. Global Xpress is, therefore, an important enabler for continued growth in global mobile broadband – it is the ‘Internet of Everywhere.”
In a series of videos Inmarsat will be taking you on a transformational connectivity journey
that is set to change the way we live our lives – watch the trailer to find out more.
The Power of Availability
New communication capabilities that have very high availability will be an enabler for the real-time transfer of significant amounts data from ship to shore and vice versa, says DNV GL in its 2015 position paper Ship Connectivity.
Potential applications include condition monitoring, remote maintenance, decision support tools and energy optimization such as those offered by engine manufacturers and system integrators, such as Rolls Royce, Wärtsila and Marorka.
In the case of Marorka, the company’s on board system can log, track, and analyse more than 500 data sources, including fuel consumption, speed, weather and draft.
The E.U. and the IMO are introducing regulations for monitoring, reporting and verification of emissions, and new satellite communications capabilities could aid in meeting these requirements by providing reliable, transparent data without unnecessary burdening ships’ crew.
Another potential environmental application would be using vessels as sailing weather stations, says DNV GL. (see WMO)
“If an advanced weather station is fitted on a vessel, relevant data may be transmitted regularly to an onshore data centre, for further analysis or data sharing.
If many vessels participate, a network with continuous feeds of weather data from many locations would be created.
This could become a meteorological Big Data application in which the collated data could be used to calibrate weather models and improve weather forecasts.”
Safety applications include the live monitoring of critical systems, says DNV GL.
This could determine the integrity and status of various safety systems and alert shoreside personnel if, for example, fire detectors are offline, watertight doors are kept open too often or if ECDIS is using an obsolete version of maps.
During emergencies, shore parties could benefit from additional data being transferred live from the vessel.
They could keep informed of the status of the navigation system and safety systems (e.g. fire and flooding status), stability information from the vessel’s loading computer and possibly video streams from strategic positions on board the vessel.
DNV GL also proposes VDR-in-the-cloud as a way of sending vessel black box data to shore on a regular basis in case the voyage data recorder is not found after an accident.
Remote control and autonomy
Ultimately, the increased reliability and capacity of data transfer could enable the controlling of ship functions from shore.
“Remote control of vessel functions will have intensive requirements regarding the communication link to the vessel,” says DNV GL.
“Firstly, the connection needs broadband in order to be able to transfer sufficient amount of information to the onshore operator and back to the vessel. The bandwidth requirements for the forward link will be smaller as it will be mainly control commands from pilot to vessel.
“Secondly, as loss of communication will result in loss of ability to control the vessel, the communication system must be highly reliable. Furthermore, the connection should have low latency to avoid an introduced lag impeding reaction times, which may be critical for adequate response times.”
The provision of a robust and dependable communication link could be provided by redundancy and diversity where several independent communication systems are used.
Backing up a satellite connection with a terrestrial connection, such as 3G or 4G, is another alternative.
If communication is lost, a fail-safe logic could be applied, so that the autonomous system configures the vessel to the safest possible state until communication is restored.
Rolls-Royce leads a project for ship automation
Satellite Number 4
Inmarsat continues to build its capacity for VSAT service technology.
A fourth GX satellite – Inmarsat-5 F4 – is currently completing construction and testing by Boeing in California.
This satellite is now likely to be launched in the second half of 2016 in order to provide additional GX network capacity.
During the course of 2016, Inmarsat will be introducing a series of market-specific, high-speed connectivity services powered by Global Xpress.
Links :
Monday, January 11, 2016
The floor of the ocean comes into better focus
Undersea mountains near
the Hawaiian Islands, from the Marine Geoscience Data System. Images of
the mountains and nearby seafloor are derived from sonar readings taken
along the paths sailed by research ships.
Read more at: http://phys.org/news/2016-01-floor-ocean-focus.html#jCp
Read more at: http://phys.org/news/2016-01-floor-ocean-focus.html#jCp
Undersea mountains near the Hawaiian Islands, from the Marine Geoscience Data System.
Images of the mountains and nearby seafloor are derived from sonar readings taken along the paths sailed by research ships.
From Phys by David Funkhouser (Columbia Univ)
The bottom of the ocean just keeps getting better.
Or at least more interesting to look at.
In an ongoing project, mappers at Lamont-Doherty Earth Observatory have been gathering data from hundreds of research cruises and turning it all into accessible maps of the ocean floor with resolutions down to 25 meters.
You can see some of the results here, at a mapping site that allows scientists—and you—to zero in on a particular location, zoom in and download topographical maps of the ocean floor.
The Lamont data has also contributed to the latest version of Google ocean map, which now offers its own more closely resolved view of the ocean floor globally.
(You can take a quick tour of the updated Google map here.)
"I love looking at everything," said Vicki Ferrini, a scientist at Lamont who oversees the team that synthesizes the data and creates the maps. Ferrini may have absorbed more data about the ocean floor than anyone; a self-professed map and data geek, she says she has her own map of the oceans in her head.
"I really like these sinuous channels in the deep sea, they're very cool to me. … There [are] clearly concentrated areas of energy that are able to scour these river-like features through the seafloor. And the [mid-ocean] ridges are all pretty cool."
A map showing the tracks of research vessels where more detailed imagery of the seafloor is available.
The new data from
Lamont covers about 8 percent of the ocean floor, a fraction of the
oceans, but a sizable piece overall of the earth's surface. The data
mostly comes as a byproduct of scientific expeditions that send research
vessels criss-crossing the seas, explained Suzanne Carbotte, a
professor of marine geology and geophysics at Lamont. The cruises may
not be focused on ocean topography at all; but as the ships sail, they
keep their measuring instruments humming and collect sonar data.
The sonar sends a pulse of sound down through the water column, and uses the speed of the sound's return to calculate depth. Data from U.S. expeditions is archived by the National Oceanic and Atmospheric Administration. Lamont processes that data, gathers more from scientists around the world, and turns it into maps.
The Google ocean map, covering the entire ocean floor, relies mostly on data collected by satellite that is curated by the Scripps Institution of Oceanography, in partnership with NOAA, the U.S. Navy and the National Geospatial Intelligence Agency, with contributions from the Japan Agency for Marine-Earth Science and Technology and Australia Geosciences-AGSO. It also incorporates the more precise data from Lamont. (A video produced by Scripps at this site offers an interesting global tour of mid-ocean ridges.)
Read more at: http://phys.org/news/2016-01-floor-ocean-focus.html#jCp
The new data from Lamont covers about 8 percent of the ocean floor, a fraction of the oceans, but a sizable piece overall of the earth's surface.The sonar sends a pulse of sound down through the water column, and uses the speed of the sound's return to calculate depth. Data from U.S. expeditions is archived by the National Oceanic and Atmospheric Administration. Lamont processes that data, gathers more from scientists around the world, and turns it into maps.
The Google ocean map, covering the entire ocean floor, relies mostly on data collected by satellite that is curated by the Scripps Institution of Oceanography, in partnership with NOAA, the U.S. Navy and the National Geospatial Intelligence Agency, with contributions from the Japan Agency for Marine-Earth Science and Technology and Australia Geosciences-AGSO. It also incorporates the more precise data from Lamont. (A video produced by Scripps at this site offers an interesting global tour of mid-ocean ridges.)
Read more at: http://phys.org/news/2016-01-floor-ocean-focus.html#jCp
The data mostly comes as a byproduct of scientific expeditions that send research vessels criss-crossing the seas, explained Suzanne Carbotte, a professor of marine geology and geophysics at Lamont.
The cruises may not be focused on ocean topography at all; but as the ships sail, they keep their measuring instruments humming and collect sonar data.
The sonar sends a pulse of sound down through the water column, and uses the speed of the sound's return to calculate depth.
Data from U.S. expeditions is archived by the National Oceanic and Atmospheric Administration. Lamont processes that data, gathers more from scientists around the world, and turns it into maps.
Welcome to a Deep Sea Vents Tour in Google Earth, where you can watch
the deepest volcanic eruption ever captured on video at the West Mata
volcano, near Fiji and learn about the exciting discovery of
hydrothermal vents.
Columbia University's Lamont-Doherty Earth
Observatory highlights Ridge 2000 discoveries in this tour now visible
with the new underwater terrain data published in Google Earth from
Columbia's Global Multi-Resolution Topography Synthesis covering half of
the ocean that has ever been mapped in detail.
The Google ocean map, covering the entire ocean floor, relies mostly on data collected by satellite that is curated by the Scripps Institution of Oceanography, in partnership with NOAA, the U.S. Navy and the National Geospatial Intelligence Agency, with contributions from the Japan Agency for Marine-Earth Science and Technology and Australia Geosciences-AGSO.
It also incorporates the more precise data from Lamont.
The seafloor off the northwest coast of the United States and southwest Canada.
From the Marine Geoscience Data System.
The satellite data details small changes in sea surface height which, through gravity, reflect the underlying topography of the sea floor.
The latest version of the Scripps-NOAA ocean map offers a resolution of roughly 500 meters—an improvement over the earlier, 1 kilometer resolution.That means one data point for every 500-meter-square grid of the seafloor.
Even that rough picture is valuable, Carbotte said.
"The coarse data does a beautiful job revealing the detailed boundaries of earth's tectonic plates and other large-scale seafloor structures, and the map covers the entire ocean," she said.
Those measurements allowed researchers to discover a new "microplate" in the Indian Ocean—a remnant from the crustal shifts that sent the Indian subcontinent crashing into Eurasia, creating (and still forming) the Himalaya mountains.
Those measurements allowed researchers to discover a new "microplate" in the Indian Ocean—a remnant from the crustal shifts that sent the Indian subcontinent crashing into Eurasia, creating (and still forming) the Himalaya mountains.
Researchers studying that plate have come up with a more precise date for when that collision began, 47.3 million years ago.
But the finer resolution mapping processed by Lamont opens up other avenues for scientists.
But the finer resolution mapping processed by Lamont opens up other avenues for scientists.
"It allows you to study the active modern processes that shape the seafloor," Carbotte said, like earthquakes and undersea landslides that can flush sediments across long distances.
A section from the Marine Geoscience Data System map shows details along the mid-Atlantic ridge.
Scientists can dive into the maps and data and use various tools at the Marine Geoscience Data System site, created to provide free public access to marine geoscience data.
Lamont-Doherty serves as the host laboratory; funding comes from the National Science Foundation, and from Google.
The mapping page, here, has a "masking" tool (at the upper right) that allows the viewer to see the tracks of research vessels and contrast the sonar data results with the broader ocean map.
Some of the more interesting features include the deep ocean trenches, the zigs and zags of fault lines where earth's crust is forming and deforming, and massive oceanic plateaus and undersea volcanoes that reflect volcanic outpourings away from the mid-ocean ridges.
There are "fabulous canyons that carve the continental margins and channels that extend out into the deeper oceans," Carbotte said.
Scientists expect to see plenty of activity along the edges of tectonic plates including at the mid-oceanic ridges, where new crust is formed from upwelling and melting of the mantle below, and at subduction zones, where enormous slabs of earth's crust collide and one plate sinks beneath another.
2015 Ocean in Google Earth Global Map Update- After.
“We're updating the entire Google ocean at once- the Scripps, NOAA, US Navy, NGA, GEBCO SRTM15plus global ocean map and the Columbia Lamont high resolution ocean map synthesis together at the same time- something that we've never done before."
Six years ago, we launched an explorable ocean seafloor in Google Earth and Maps.
Since then, Google Earth has been downloaded over 2 billion times, and Google Maps has over 100 million users a month, enabling a new generation of virtual ocean explorers.
Three years ago, we released the 2nd major global update in partnership with the Scripps Institution of Oceanography, NOAA, the US Navy, NGA, and GEBCO with major contributions from IFREMER and the IBCAO arctic synthesis), resulting in a 1 km resolution global map.
Today, we announce our 3rd and biggest update to our global ocean map with the first ever SRTM15 global grid curated by Scripps Institution of Oceanography, in partnership with NOAA, the US Navy, NGA, and with major contributions from JAMSTEC (2.2% of the seafloor), Australia Geosciences- AGSO (0.5% of the seafloor) and Lamont-Doherty Earth Observatory at Columbia University with their latest high resolution synthesis.
There’s a brand new major discovery- the first microplate discovered in the Indian Ocean over an area larger than the state of West Virginia, named the “Mammerickx Microplate” after Jacqueline Mammericks, who is the author of all the original GEBCO maps in the Pacific Ocean.
The full data reference list is here.
New areas to explore include the Philippine Sea, Ryukyu Trench, the Seafloor fabric east of Hawaii, the continental margins around Australia, and the Reykjanes Ridge.
Incorporating data from 3 satellite altimeters significantly improves the spatial resolution of areas having no ship coverage.
The SRTM15 grid is in the public domain and available online here.
Our partners at the Lamont-Doherty Earth Observatory at Columbia University have curated more than 33 years of ship-based data from nearly 900 global research cruises conducted aboard more than 20 ships.
This latest update representing 3 years of work adds nearly 1.6 million ship-track km of coverage from 400 additional cruises conducted by 18 different institutions including the Schmidt Ocean Institute.
This release brings the total ship-track coverage to 28 million square km of the ocean at 100m resolution.
This is a 3% increase from the 2011 publication, bringing the total area in the Columbia compilation to ~8% of the ocean in high resolution.
High-res underwater mapping is vital to understanding important earth processes such as how tsunamis spread around the globe.
This is the best multi-resolution map of the ocean that’s been created in history.
“We're updating the entire Google ocean at once- the Scripps, NOAA, US Navy, NGA, GEBCO SRTM15plus global ocean map and the Columbia Lamont high resolution ocean map synthesis together at the same time- something that we've never done before."
Six years ago, we launched an explorable ocean seafloor in Google Earth and Maps.
Since then, Google Earth has been downloaded over 2 billion times, and Google Maps has over 100 million users a month, enabling a new generation of virtual ocean explorers.
Three years ago, we released the 2nd major global update in partnership with the Scripps Institution of Oceanography, NOAA, the US Navy, NGA, and GEBCO with major contributions from IFREMER and the IBCAO arctic synthesis), resulting in a 1 km resolution global map.
Today, we announce our 3rd and biggest update to our global ocean map with the first ever SRTM15 global grid curated by Scripps Institution of Oceanography, in partnership with NOAA, the US Navy, NGA, and with major contributions from JAMSTEC (2.2% of the seafloor), Australia Geosciences- AGSO (0.5% of the seafloor) and Lamont-Doherty Earth Observatory at Columbia University with their latest high resolution synthesis.
There’s a brand new major discovery- the first microplate discovered in the Indian Ocean over an area larger than the state of West Virginia, named the “Mammerickx Microplate” after Jacqueline Mammericks, who is the author of all the original GEBCO maps in the Pacific Ocean.
The full data reference list is here.
New areas to explore include the Philippine Sea, Ryukyu Trench, the Seafloor fabric east of Hawaii, the continental margins around Australia, and the Reykjanes Ridge.
Incorporating data from 3 satellite altimeters significantly improves the spatial resolution of areas having no ship coverage.
The SRTM15 grid is in the public domain and available online here.
Our partners at the Lamont-Doherty Earth Observatory at Columbia University have curated more than 33 years of ship-based data from nearly 900 global research cruises conducted aboard more than 20 ships.
This latest update representing 3 years of work adds nearly 1.6 million ship-track km of coverage from 400 additional cruises conducted by 18 different institutions including the Schmidt Ocean Institute.
This release brings the total ship-track coverage to 28 million square km of the ocean at 100m resolution.
This is a 3% increase from the 2011 publication, bringing the total area in the Columbia compilation to ~8% of the ocean in high resolution.
High-res underwater mapping is vital to understanding important earth processes such as how tsunamis spread around the globe.
This is the best multi-resolution map of the ocean that’s been created in history.
Explore the ocean seafloor with Columbia University's Lamont-Doherty
Earth Observatory Global Multi-Resolution Topography (GMRT) Synthesis
covering half of all of the ocean that has ever been mapped in detail,
an area larger than North America.
You can also view new data of Cordell
Bank and the Gulf of the Farallones off of the California coast from
California State University Monterey Bay (CSUMB) along with a beautiful
50 meter synthesis of the Hawaiian Islands from the University of
Hawai'i at Manoa's School of Ocean and Earth Science and Technology
(UHM-SOEST).
But the new mapping has helped scientists see that there's also geologic activity in the broad interior spaces of the oceanic plates, Carbotte says, such as fields of volcanic seamounts of many sizes, and far-reaching channels of sediments transported into the deep ocean.
The finer resolution helps scientists study how the crust forms at mid-ocean ridges and then deforms before descending into earth's mantle, bending and faulting along subduction zones.
The finer resolution helps scientists study how the crust forms at mid-ocean ridges and then deforms before descending into earth's mantle, bending and faulting along subduction zones.
"With the new detailed data from many subduction zones, we can conduct comparative studies of this bend faulting and relationships to the rate of subduction, the age of the plate and sediment cover, and [that] helps us in … understanding the subduction process," Carbotte says.
Multibeam sonar
readings from the R/V Falkor opened up the details of Scott Reef, off
the west coast of Australia, to view at about a 10 m resolution, shown
here from the GeoMapApp.
Read more at: http://phys.org/news/2016-01-floor-ocean-focus.html#jCp
Read more at: http://phys.org/news/2016-01-floor-ocean-focus.html#jCp
Multibeam sonar readings from the R/V Falkor opened up the details of Scott Reef, off the west coast of Australia, to view at about a 10 m resolution, shown here from the GeoMapApp.
The process of
mapping the ocean floor in detail continues; there's enough data already
available to keep Carbotte, Ferrini and the staff busy for a long time.
Covering just 8 percent of the oceans has involved hundreds of cruises
over millions of miles. The oceans are so large that a thorough mapping
would involve an estimated 125 to 200 ship-years of cruises (mapping on
land, even on distant planets, can happen far more quickly using
satellites). The Lamont crew updates their maps every six months.
Lamont has been collecting measurements and other data about the oceans for more than half a century. The first comprehensive map of the global ocean floor was created by Lamont oceanographers Marie Tharp and Bruce Heezen and published in 1977. In the 1980s, another Lamont scientist, William Haxby, used satellite measurements to compose the first "gravity field" map of the oceans. Now, the same database contributing to Google Earth feeds Lamont's EarthObserver, a global scientific mapping application for iPads and other mobile devices.
When we step onto an airliner, "We have map displays at our seats that show the flight paths, and it used to be the ocean was just a single flat, featureless blue," Carbotte said. "Now they make use of these new ocean floor maps, so when you're flying across the middle of the Atlantic, you can see the mid-ocean ridge right from your airplane seat."
Read more at: http://phys.org/news/2016-01-floor-ocean-focus.html#jCp
Lamont has been collecting measurements and other data about the oceans for more than half a century. The first comprehensive map of the global ocean floor was created by Lamont oceanographers Marie Tharp and Bruce Heezen and published in 1977. In the 1980s, another Lamont scientist, William Haxby, used satellite measurements to compose the first "gravity field" map of the oceans. Now, the same database contributing to Google Earth feeds Lamont's EarthObserver, a global scientific mapping application for iPads and other mobile devices.
When we step onto an airliner, "We have map displays at our seats that show the flight paths, and it used to be the ocean was just a single flat, featureless blue," Carbotte said. "Now they make use of these new ocean floor maps, so when you're flying across the middle of the Atlantic, you can see the mid-ocean ridge right from your airplane seat."
Read more at: http://phys.org/news/2016-01-floor-ocean-focus.html#jCp
The process of mapping the ocean floor in detail continues; there's enough data already available to keep Carbotte, Ferrini and the staff busy for a long time.
Covering just 8 percent of the oceans has involved hundreds of cruises over millions of miles.
The oceans are so large that a thorough mapping would involve an estimated 125 to 200 ship-years of cruises (mapping on land, even on distant planets, can happen far more quickly using satellites).
The Lamont crew updates their maps every six months.
Lamont has been collecting measurements and other data about the oceans for more than half a century.
New Global Seafloor Map Incorporated into Google Ocean
Updated Google Earth image at right shows new seafloor features in the western Philippine Sea compared to earlier version
see : Scripps
Lamont has been collecting measurements and other data about the oceans for more than half a century.
The first comprehensive map of the global ocean floor was created by Lamont oceanographers Marie Tharp and Bruce Heezen and published in 1977.
In the 1980s, another Lamont scientist, William Haxby, used satellite measurements to compose the first "gravity field" map of the oceans.
Now, the same database contributing to Google Earth feeds Lamont's EarthObserver, a global scientific mapping application for iPads and other mobile devices.
When we step onto an airliner, "We have map displays at our seats that show the flight paths, and it used to be the ocean was just a single flat, featureless blue," Carbotte said.
Global map of ocean depths and land elevations,
with data mapped to colour (cyan to dark grey) by quantile.
courtesy of geotheory.co.uk
"Now they make use of these new ocean floor maps, so when you're flying across the middle of the Atlantic, you can see the mid-ocean ridge right from your airplane seat."
Links :
Links :
- GeoGarage blog : Seafloor features are revealed by the gravity field / New maps reveal California's sensational seafloor geography / Monterey Canyon: Stunning deep-sea topography revealed / New map exposes previously unseen details of seafloor / USGS maps California seafloor in unprecedented detail /'Un-mappable' Great Barrier Reef finally mapped in 3D / Bing Maps now shows ocean floor topography / Marie Tharp: the woman who mapped the ocean floor / Secretly mapping the sea floor / New bathymetry in Google Earth / New map reveals New Zealand's seafloor in stunning detail / NIWA survey reveals deep water canyons off Otago coast (NZ) /A virtual first look at unexplored seafloor : Farallon islands / 3-D maps reveal depths of sea floor
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