Canada CHS update in the GeoGarage platform

45 nautical raster charts updates + 1 chart added

see : GeoGarage News

New report and maps: Rising seas threaten land home to half a billion

Redesign of the sea level rise maps for every coastline around the globe

by ClimateCentral

Carbon emissions causing 4°C of warming — what business-as-usual points toward today —- could lock in enough sea level rise to submerge land currently home to 470 to 760 million people, with unstoppable rise unfolding over centuries.
At the same time, aggressive carbon cuts limiting warming to 2°C could bring the number as low as 130 million people.

How to avoid the next Atlantis

These are the stakes for global climate talks December in Paris.
Our analysis details the implications of different warming scenarios for every coastal nation and megacity on the planet, and our globally searchable Mapping Choices tool maps them.
We are also publishing Google Earth fly-over videos and KML contrasting these different futures for important cities around the world, and printable high-resolution photorealistic images of select global landmarks. We have made these visualizations embeddable and downloadable.
These are the stakes for global climate talks, in pictures.

Some of our major findings include: China, the world’s leading carbon emitter, leads the world, too, in coastal risk, with 145 million people living on land ultimately threatened by rising seas if emission levels are not reduced.
China has the most to gain from limiting warming to ​2°C, which would cut the total to 64 million.
Twelve other nations each have more than 10 million people living on land at risk, led by India, Bangladesh, Viet Nam, Indonesia, and Japan.
The U.S. is the most threatened nation outside of Asia, with roughly 25 million people on implicated land.
Meeting the 2°C​ goal would cut exposure by more than half in the U.S., China, and India, the world’s top three carbon emitters, as well as in many other nations.
Global megacities with the top-10 largest threatened populations include Shanghai, Hong Kong, Calcutta, Mumbai, Dhaka, Jakarta, and Hanoi.

Explore the full interactive map >>

Links : 

• NOAA : Sea Level Rise and Coastal Flooding Impacts

Safe at sea with satellites

At sea, space technology is used to help save lives every day: managing traffic between ships, picking up migrants and refugees in distress or spotting oil spills.
The European Space Agency is once again at the forefront developing new technologies and satellites: to keep us safe at sea and to monitor the environment.
Space makes a difference here on Earth and certainly at sea where there is no infrastructure.

Book : Pacific: The Ocean of the Future by Simon Winchester review – does salvation lie in the world’s ‘dominant entity’?

Travelling the circumference of the truly gigantic Pacific, Simon Winchester tells the story of the world's largest body of water, and - in matters economic, political and military - the ocean of the future.

The Pacific is a world of tsunamis and Magellan, of the Bounty mutiny and the Boeing Company.

It is the stuff of the towering Captain Cook and his wide-ranging network of exploring voyages, Robert Louis Stevenson and Admiral Halsey.

It is the place of Paul Gauguin and the explosion of the largest-ever American atomic bomb, on Bikini atoll, in 1951.

It has an astonishing recent past, an uncertain present and a hugely important future.

The ocean and its peoples are the new lifeblood, fizz and thrill of America - which draws so many of its minds and so much of its manners from the sea - while the inexorable rise of the ancient center of the world, China, is a fixating fascination.

The presence of rogue states - North Korea most notoriously today - suggest that the focus of the responsible world is shifting away from the conventional post-war obsessions with Europe and the Middle East, and towards a new set of urgencies.

Navigating the newly evolving patterns of commerce and trade, the world's most violent weather and the fascinating histories, problems and potentials of the many Pacific states, Simon Winchester's thrilling journey is a grand depiction of the future ocean.

From The Guardian by Philip Doare

Simon Winchester argues that our destiny will be dictated by the Pacific’s vast expanses  

Will the Pacific save us?
In his biography of an ocean, Simon Winchester finds an optimistic note among all the doom we humans trail in our wake.
This enormous body of water, which covers roughly a third of the planet’s surface, has become a cistern for our western sins.
We have raided its indigenous peoples and animals; our world wars and nuclear tests have contaminated its islands and seas.
How does it repay us?
By absorbing the heat caused by our excessive burning of fossil fuels, acting as a “gigantic safety valve” to global warming.
Archipelagos may be overwhelmed and coral reefs die, but in the end, Winchester intimates, the Earth will survive because of “the dominant entity on the planet” – all 64 million square miles of it.

As a companion to his magisterial Atlantic, Winchester’s Pacific is an equally digressive book, worthy of Herman Melville, and full of wondrous anecdotes that would fuel an entire series of QI.
Sikh guards were employed by the British to guard their colonial armouries because their religion forbade smoking.
Newly discovered deep-sea vents, where life itself may have begun, recycle all of the planet’s oceanic water every 10 years.
All of the continents could fit into this one ocean.
To encompass this vastness in one book, Winchester selects a series of key moments in the Pacific’s recent history.
He starts in 1950 with a bravura chapter, The Great Thermonuclear Sea.
It is not a pretty story.
Places recently ravaged by bloody war faced a new outrage: the multiple detonation of atomic bombs.
Far from the Berlin Wall, the cold war was rehearsed in blood-warm seas. Islands, and islanders’ bodies, became test sites for the apocalypse.
One explosion was witnessed by a reporter from the New York Times.
“It was like watching the birth and death of a star, born and disintegrated in the instant of its birth... it lighted up the sky and ocean with the light of many suns, a light not of the earth”.

Not all of Pacific’s scenes are so dark.
A scintillating chapter on the transition of surfing from Hawaii to California in 1907, courtesy of a half-Hawaiian, half-Irish surfer named George Freeth, hymns the “erotic, arching elegance” of this democratic use of the sea.
We follow the birth of the Sony Corporation in Japan and the sacking of Gough Whitlam in Australia, both tectonic shifts in the cultural rise of the Pacific Rim.
Western interests fall, with the symbolic sinking (probably due to sabotage) of the Queen Elizabeth in Hong Kong’s harbour; Prince Charles sails over its wreck in 1997 as he and the British leave the colony to new rulers described by the prince as “appalling old waxworks”.

But the greatest power of the Pacific is elemental.
It is where our weather is born, and in a brilliant chapter on El Niño and climate change, Winchester shows that the placid ocean is becoming steadily more stormy, wreaking indiscriminate havoc from the Philippines to Australia.
At the same time, those waters have become witness to “a sudden and wholesale redistribution of world power”, from America to China.
Far from running scared at the notion, Winchester wonders if it might not actually be a good thing if we were to allow the east its turn, rather than falling back on our old notions of racial superiority.
The Pacific is our future ocean.
And in this provocative, elegant book, it has found a new and lucid storyteller.

Magnetic anomalies of the world's largest volcano

 Tamu Massif, is a massive shield volcano that rises over 20 kilometers into the air
and covers an area the size of California or Japan.

Photo credit: Will Sager. 

From SchmidtOcean

Tamu Massif, located about 1000 miles east of Japan, is the largest known single volcano on Earth, but the process that created it remains a mystery.
With an area equivalent to Japan or California, the undersea volcanic mountain - a part of the western Pacific Shatsky Rise oceanic plateau - is believed to have formed during the late Jurassic period. Exactly how it formed in the age when dinosaurs still ruled is unknown, but scientists on this 32-day expedition aboard Falkor hope to reveal its origins.

Tamu Massif is located within the Shatsky rise.

Credit: Will Sager.

 Tamu Massif in the GeoGarage platform

Principal Investigator William Sager from the University of Houston Department of Earth and Atmospheric Sciences, and Geophysicist Masao Nakanishi from Chiba University, along with their science team, will transit over the western Pacific Ocean to Shatsky Rise, an undersea oceanic plateau where Tamu Massif is located.
As one of the few oceanic plateau volcanoes formed during a time of geomagnetic reversals, Tamu Massif holds a unique record of undersea geographic formation: magnetic anomalies in the oceanic crust.
This makes it easier to understand the underwater volcano’s history and the key interactions it has with the mid-ocean ridges.

Reversing poles

To appreciate geomagnetic reversals, one needs to know some aspects of Earth’s magnetic field.
Our planet has a magnetic field with North and South Poles, just like a bar magnet.
Geophysicists reason that the Earth’s magnetic field is created by the motion of the fluid iron outer core, which creates electric currents that in turn produce the magnetic field.
At certain times in the past, core flow changed, causing the poles to flip - what was once the North Pole is now the South, and vice versa.
Lava becomes magnetized as it solidifies to rock on the ocean floor, creating a record of the magnetic pole direction at the time.
The magnetic lava rock perturbs the Earth’s magnetic field, causing a negative or positive “magnetic anomaly” depending on whether it adds to or subtracts from the Earth’s field. 
In the ocean basins, the mid-ocean spreading ridges, divergent plate boundaries where oceanic crust is formed, record linear magnetic anomalies that parallel the spreading ridge crest.
Correlating the magnetic reversal pattern to time, scientists have used these magnetic anomalies to determine the age of the oceanic crust and the pattern of its development.
Because Tamu Massif formed during a time of geomagnetic reversals, its lavas also preserve magnetic anomalies that can be interpreted by scientists to show the construction of the volcano.

Using multibeam sonar systems and a marine magnetometer, the science team and Falkor crew plan on collecting seafloor and magnetic data in October and November of this year, to build a well-constrained magnetic anomaly map.
This map will allow for a better understanding of both Tamu Massif formation and its internal structure.
While it will not be possible to completely cover all of Tamu Massif with multibeam sonar bathymetry data, new underwater depth information collected on the cruise will substantially improve the knowledge of Tamu Massif topography and structure, all of which will help in understanding the monster volcano hidden beneath the sea.

 Cruise survey plan. Heavy lines show proposed cruise tracks.

Ingress and egress transit tracks are not shown.

Credit: Will Sager.

The Birth of a Giant

Shatsky Rise is one of the largest oceanic plateaus and is believed to have formed at the triple junction of three tectonic plates: the Pacific, the Farallon, and the Izanagi.
Like most oceanic plateaus, it is a huge volcanic mountain range consisting mainly of basalt rock covered with a generally thin veneer of sediments.
How such a massive volcano as Tamu Massif formed in this area is unknown.
Did it erupt as a huge boil on top of the mid-ocean ridges?
Did it disrupt and reorganize the seafloor, spreading the ground wide at the triple junction?
The answer to these fundamental questions will help scientists understand how oceanic plateaus form and how such volcanic eruptions interact with mid-ocean ridges and their underlying magma convection system.

 Model of hotspot volcanism.  A. Rising mantle plume. B. Outpourings of basalt generate the oceanic plateau. C. Less voluminous activity produces a volcanic chain. Image from Tasa Graphics.

Plume Head versus Fertile Mantle

There are two main, competing models that are debated about Tamu Massif’s formation.
The “plume head” hypothesis proposes that hot mantle under the ocean floor, begins to rise, forming a growing column of slowly flowing material.
When this “plume head” reaches the base of the outermost shell of the Earth, it bursts through, causing a massive eruption and intrusion of igneous material, as well as forming large oceanic plateaus (if undersea, as the case would be here).
This model gained acceptance mainly because geochronology data from several other geographic features appear consistent with short-lived and massive outpourings of lava.
This hypothesis excites Earth scientists because it implies periods of massive flux of mantle material to the surface.
Moreover, such massive eruptions also imply the release of large quantities of heat and gasses, which could have far-ranging environmental effects.
An alternative idea - the “fertile mantle” hypothesis - suggests eruptions occur because plate boundaries and cracks are releasing pressure above areas of upper mantle with lower melting temperatures.
This hypothesis implies that the source of plateau magma is shallow, and that the massive vertical mantle movement of the “plume head” hypothesis does not occur.
Simply, a “plume head” creates a large volcano in a huge, short, gushing eruption.
At a much slower pace, and a “fertile mantle” fosters extended surges of molten core, releasing stress at plate boundaries and forming a series of merging volcanoes over a longer period of time.
Oceanic plateau structure is key to figuring out whether this dichotomy is true, but plateau structure is poorly understood because these features are so large in size, as well as hidden and inaccessible beneath the sea.
Today, earth scientists still debate which of these two mechanisms provide a better explanation for large areas of volcanic rocks, known as igneous provinces.
Many oceanic plateaus contain significant complexities – unexpected ingredients or evidence - that do not lend themselves to clear origin certainty.
Depending on whom you talk to, the “plume head” model either needs amendments or should be dismissed.
As is often the case in science, neither hypothesis may be entirely correct, but these two concepts provide a framework for debate that will ultimately help geoscientists understand this important flux of material to the Earth’s surface.

credit Schmidt Ocean Institute

Translating Evidence into Fact

The linear magnetic anomalies in the mid-ocean ridges are key to understanding how Tamu Massif formed.
One side (north) of Tamu Massif seems to have magnetic lineations, but the other (south) seems to have a broad, coherent anomaly caused by the whole volcano.
On this side, massive lava flows have been cored and imaged by acoustic profiling.
Magnetic lineations imply well-behaved, limited magmatic eruptions whereas the coherent anomaly implies a massive eruption.
Thus, it appears that Tamu Massif may have a Jekyll and Hyde personality.
To date, the magnetic data has been collected sparsely, and the science team hopes this cruise will fill the existing gaps with precise mapping of undersea geography and magnetic charting.
The goal is to combine the newly collected data with existing data to construct both magnetic and bathymetric contour maps of Tamu Massif.
Perhaps a revelation from tiny magnetically charged particles will explain the creation of one of Earth’s largest physical features.

 Links :

• Schmidt Ocean Institute : Closing Thoughts from Chief Scientist Dr. William Sager
• Marine GeoGarage : Underwater volcano is Earth's biggest
• Sci-news : Newly-Discovered Seamount Named after Research Vessel Falkor