Saturday, January 27, 2018

ECMWF 25 years of ensemble prediction fro weather

Lead Scientist Roberto Buizza, Director-General Florence Rabier and NOAA meteorologist Tom Hamill explain the rationale behind ensemble forecasting and set out what the future holds. 

Links :

Friday, January 26, 2018

Hydrography in the 70's

Before the arrival of GPS and satellites :
follow a team of SHOM hydrographers which will carry out a coastal mapping point using techniques from the 1970s, including optical radio guidance.

Ancient maps show islands that don't really exist

The fictional island Frisland appears in the lower left corner of this 1596 map of the Arctic
by Gerardus Mercator.
Image courtesy of the Osher Map Library and Smith Center for Cartographic Education at the University of Southern Maine

From National Geographic by Greg Miller

For centuries, mapmakers have conjured up islands that only exist in the imagination.

The treaty that drew the first borders of the newly established United States after the Revolutionary War refers to an island that does not exist.
The northern boundary of the new nation, the 1783 Treaty of Paris declared, shall pass “through Lake Superior northward of the Isles Royal and Phelipeaux.”
It sounds clear enough, but when surveyors went out to map the border in the 1820s they discovered a problem: Isle Phelipeaux was not there.

The story behind the nonexistent island Brasil, shown on this 1633 map in the Atlantic Ocean west of Ireland (far left), is a mystery.

The long and fascinating history of such phantom islands is the topic of Malachy Tallack’s new book, The Un-Discovered Islands, which he discussed recently in an interview with National Geographic. Inspired by the book, we’ve rounded up a collection of vintage maps that feature islands that don’t actually exist.

Saint Brendan, an early Christian monk, is the namesake of a nonexistent island in the North Atlantic (right of center, near the top). 
He’s also reputed to have held mass on the back of a whale, as shown on this 1621 map.

“Frisland,” for example, appears to have been the invention of a wealthy Venetian named Niccolò Zeno, who wrote a book in 1558 claiming that his ancestor had discovered the New World before Columbus.

This detail from a 1558 map that accompanied Niccolò Zeno’s dubious book, in which he claimed that his ancestor discovered the New World before Colombus, shows the faux island of Frisland (left of center, near the bottom).

Historians now consider the claim bogus, but it was influential at the time, and the islands it described appeared on maps for more than a century.

Gerhard Mercator included a circular inset map of Frisland, complete with several nonexistent towns, on his 1595 map of the region around the North Pole.

This was, after all, the era when people were just beginning to explore the world’s oceans, and news traveled slowly by modern standards.

This 1720 map shows the mythical island of Thule, first reported by the Greek explorer Pytheas around 330 B.C., off the north coast of Scotland and in the inset at top left.

Some islands were believed to have existed and later sunk. Sarah Ann Island, a speck of land in the Pacific Ocean claimed by the United States under the 1856 Guano Act, a law permitting the appropriation of islands covered with bird droppings (a valuable source of fertilizer at the time).
The island happened to be in the path of a total solar eclipse in 1937, but when astronomers went to seek it out, the island was gone.
Most likely it had never been there, but newspapers reported that it had sunk, and the rumor stuck.

For centuries, mapmakers drew California as an island, as in this Dutch map from 1689.

Other “un-discovered” islands, like Phelipeaux, appear to be the result of outright fraud.
This island appears on a map by a Virginia-born British loyalist named John Mitchell that was used by both sides to negotiate the Treaty of Paris (see below).

 Four nonexistent islands are visible in this detail from John Mitchell’s map: Phelippeaux, Pontchartrain, Maurepas, and St. Anne.

Mitchell isn’t at fault for the faux island, however.
He simply copied the island from an older map.
The island’s name, together with the names of three other nonexistent Lake Superior islands, Pontchartrain, Maurepas, and St. Anne, betray the origin of the ruse.
In the 1720s, a count named Jean-Frédéric Phélypeaux had served as a French secretary of state.
He happened to have estates named Pontchartrain and Maurepas, and his family’s patron saint just happened to be St. Anne.
Apparently, someone was kissing up to the count by inventing islands named in his honor.
The sycophant appears to have been an explorer named Pierre François Xavier de Charlevoix, whose voyages in the region had been funded by the good count Phélypeaux.
The four imaginary islands first appear on a map commissioned for a book published by Charlevoix in 1744.
The fraud went undetected for nearly a century until another treaty finally erased them from maps for good in 1842.
“This little lie that an explorer told became entangled in a really important part of history,” Tallack says.
“I find that really fascinating.”

Sandy Island, which appears in the top left corner of this 1921 National Geographic map, was “un-discovered” once and for all in 2012.
 The same 1921 map depicts Morell Island, which doesn’t appear on modern maps, at the far northwest end of the Hawaiian Island chain.

One of the most recent island un-discoveries happened in 2012, when an Australian research vessel reported that Sandy Island, which maps depicted off the coast of New Caledonia in the South Pacific, was most definitely not there.
Within weeks the National Geographic Society announced that Sandy Island would be stricken from all of its maps, and other mapmakers followed suit.
Google removed Sandy Island from its maps, too, but people continued to post photos at its former location.
The photos were mostly meant as a joke, Tallack says, but they also hint at the powerful pull islands exert on the human imagination.
“Because their borders are well defined we can project our ideas onto them much more easily than we can with other places.”

Links :

Thursday, January 25, 2018

CSIRO to launch 'sailing drones' to monitor Southern Ocean

Autonomous, ocean-going vessels have been launched from Alaska for oceanic research in the Bering Sea.
NOAA has partnered with Saildrone, Inc. to monitor the vital signs of the sea–wind, temperature and salinity, to take a look at important Walleye pollock fish stocks, track Northern fur seals and locate right whales through sound.

From ComputerWorld by George Nott

A fleet of unmanned autonomous sailing drones will be launched from Hobart to monitor the notoriously treacherous Southern Ocean.

The three sea-surface drones – from San Francisco-based start-up Saildrone – will initially collect data on temperature, salinity, and ocean carbon levels, to provide estimates of biomass in the water column below.

The vessels have been commissioned by CSIRO's Oceans and Atmosphere group, as part of a five-year research partnership with Saildrone.

CSIRO Australia

The USVs (unmanned science vehicles) are launched and retrieved from a dock, and navigate to a predetermined destination using wind power, travelling at an average speed of 3 to 5 knots.

Each drone can then hold its position or perform set courses to survey an area, and can be at sea for up to a year at a time.
Data is transmitted back to shore via satellite and delivered to researchers via Saildrone's API.

"Saildrones are long-range research platforms that can be sent to remote locations for an extended period of time, delivering real-time data back to scientists that was previously impossible to collect," said CSIRO research group leader Andreas Marouchos.

Saildrones tested in San Francisco

The ability to quickly re-task the drones remotely means CSIRO can deploy them to monitor difficult to predict natural events like marine heat waves or toxic algal blooms that in the past would have required extensive planning and expense for a ship and crew.
"There's lots of opportunity to collect very interesting data with the drones across Australian waters and particularly in areas of ocean energy research in the Southern Ocean and in Antarctic waters where we see very little vessel variability and vessel access," Marouchos said.
"We're also equipping the systems with a scientific echo sounder which will insonify the water column, basically ping the water column with an acoustic pulse which allows us to look at the biota, the fish, the critters in the water column as well as potential bubble seeps coming from the ocean floor," he added.

Wing on the waves

The 20-foot 'wing', or sail, of the drones has been developed over a 10-year period by Saildrone's founder, British engineer Richard Jenkins.
It is similar to the design used on the Greenbird, the vehicle Jenkins piloted to break the world land speed record for a wind-powered vehicle in 2009.
He reached a speed of 202.9 km/h on the dry plains of Ivanpah Lake in Nevada, a record that still stands today.
Jenkins began to apply the wing design to a sea-going vessel in 2012. The company's vessels have covered more than 60,000 nautical miles.

 Saildrone in stormy Bering Sea

"The Saildrone works with a combination of wind and solar using this unique patented wing. We harness the wind energy to push the vehicle along and then we use solar to charge the batteries and that runs the computers on board. So it doesn't consume anything while it goes along and so it can stay at sea almost indefinitely," Jenkins said.
"Autonomy is a key technology for accessing the southern oceans, which are understudied due to the rough seas and the limited number of vessels that regularly pass through the region," he added.

Salty sea bots

The Saildrones join a growing number of unmanned vessels monitoring Australia's surrounding waters.

The Saildrones are expected to launch in March.

In October, the Australian Institute of Marine Science (AIMS), completed a seven-day, 200 nautical mile trial voyage of its Wave Glider 'surfing robot'.
The vessel is the first of a number of technologies being put to work on the Great Barrier Reef by AIMS, the result of a five-year joint research agreement with aerospace giant Boeing.
Work is also underway to investigate the use of medium-range unmanned aerial systems equipped with hyperspectral cameras to collect high-quality imagery for seabed habitat mapping, modelling and classification, reef monitoring, and potentially 3-D reef reconstructions.

CSIRO operates a number of Autonomous Underwater Vehicles (AUVs), like the Starbug X which was built by engineers at its Hobart base.

The organisation also uses a number of robotic Argo floats, which drift at a one to two kilometre depth for ten days before ascending to the surface measuring temperature and salinity as they rise. The data is then transmitted to satellites, before the float dives and starts a new cycle.

Links :

Wednesday, January 24, 2018

The Agency that helped create the Internet now wants to wire the Ocean

DARPA promulgates vision of sensor-based "Ocean of Things"
aiming to to gauge the Seven Seas

From NewsDeeply by Paul Tullis

DARPA, the U.S. military’s R&D arm, is seeking proposals to deploy as many as 50,000 low-cost sensors across the ocean to gather data on marine conditions, but scientists say that the plan poses a significant technological challenge.

The Defense Advanced Research Projects Agency has had a hand in some of the most transformational innovations of the last half-century, including the computer network that evolved into the internet, the graphical user interface and passive radar.
Now DARPA is seeking proposals for what could be the next big thing: a network of intelligent floats “to enable persistent maritime situational awareness over large ocean areas.”

 Artist's cocept of DARPA's Ocean of Things programme.
“We plan to create floating sensor networks that significantly expand maritime awareness at a fraction of the cost of current approaches.” 
Credit : DARPA Agency

In other words, the “Ocean of Things,” as the agency describes the initiative.
It’s the marine version of the terrestrial “Internet of Things” – networked devices that communicate information about themselves to their users and to other devices, such as the Nest thermostat, which allows remote control of a house’s heating and air conditioning system, or a refrigerator that tells you when you’re out of milk.
“Head out to most parts of the open ocean, however, and no such capability exists for real-time monitoring of maritime activity,” DARPA noted in a statement.

Each float could collect environmental data such as water temperature, salinity, sea state and location, and detect the presence of vessels and marine mammals, transmitting the information via satellite.
Separately, private companies or academic institutions would develop data analytics software to process and make sense of all those bits.

The infrastructure of the Digital Ocean.
(Courtesy of Liquid Robotics, a Boeing Company)

“It’s great to see someone putting money behind this – particularly DARPA,” said Roger Hine, cofounder and chief technical officer of Liquid Robotics, a Silicon Valley company owned by Boeing that manufactures a self-propelled autonomous robot called the WaveGlider.
Liquid Robotics has proposed a “Digital Ocean” to integrate and connect devices and systems underwater, on the surface and onshore to expand understanding of the two-thirds of the planet that consists of the ocean.
“I’m really excited to see this happen,” Hine added.

The scientific case for collecting the information the Ocean of Things seeks is clear, said Jules Jaffe, a professor at Scripps institution of Oceanography at University of California, San Diego.
Jaffe designed a small swarm of underwater robots as well as the underwater imaging system used to find the Titanic.
Without a clear commercial marketplace, the private sector has lacked incentive to develop the devices and networks DARPA envisions.
“Government support is important,” he said.

 A NEMO float, part of the global Argo network of sensors, deployed in the Arctic. 
Courtesy of Argo

But Jaffe, Hine and others raised significant doubts about whether DARPA can achieve its program objectives within the constraints it has set.
The call for proposals limits the cost of the floats to $500 a piece, indicating DARPA will acquire 50,000 of them, and asks bidders to use materials “minimizing impact to the marine environment” with “biodegradable packing materials/floats” to the extent possible.

Hine pointed out that a battery sizeable enough to power such a device probably costs around $100, and the Iridium satellite modem DARPA requires is about another $100.
“It doesn’t leave a lot of budget for the actual sensing payload,” he said.

The agency listed salinity as a “potential” component of the suite of sensors, but Jaffe, who has decided not to participate in the DARPA program because “the bigger these [programs] get, the more of a pain in the ass they are,” said the least expensive device that does that costs $1,500.
With a more limited payload, though, “It’s not impossible” DARPA could acquire 50,000 intelligent floats for $500, he said.
“They’re challenging researchers to achieve aggressive goals.”

Another researcher with experience building underwater autonomous vehicles, who didn’t want to be named criticizing DARPA for fear of losing out on future funding opportunities, worries about the environmental impact of the program if it scales up.
Just 50,000 devices won’t provide much resolution of the ocean, so “scale is what makes it worth doing this research,” the researcher said.
“They have electronics, a battery on board. Putting more of them out there, I do worry about the environmental impact of these objects.”

Practical concerns are another obstacle to realizing an “Ocean of Things” as DARPA has defined it, this researcher said: “They’re going to find it really difficult to keep [individual floats] in place.
With a significant weather pattern, large- or small-scale eddies can create vortices so you end up with all the sensors in one location. Then you lose the resolution you’re hoping for.”

Hine agreed that eddies or drifting onshore are among the “significant limitations” to a float with no propulsion mechanism.
“It’s going to require a lot of engineering to make a dirt-cheap piece of electronics that actually does something useful,” he said.

John Waterston, DARPA program manager for Ocean of Things, told Oceans Deeply that, “DARPA is pushing to drive costs down on the individual floats, which is key to being able to deploy in large numbers.”
“With production rates of tens of thousands, DARPA expects that a sound business can be developed,” he added.
“We strongly believe that a well-designed float could be sufficiently modular as to be able to host a variety of sensors [which] can be switched out and usable for a variety of potential customers such as” the National Oceanic and Atmospheric Services, Department of Homeland Security “and even commercial organizations.”

If DARPA is successful, said Ryan Kastner, a UCSD professor of computer science and engineering who builds computer systems for oceangoing robots, “you’ll get an amazingly greater amount of spatial data than we have now – orders of magnitude more.” He estimated that a device that can do some of what the agency hopes would be possible in five to 10 years.
“DARPA can certainly push this sort of thing,” he said.

And that’s just what DARPA should be doing in this area, Hine maintained.
“Not all these questions should be answered at the beginning of a project like this,” he said.
“It’s good to be diving in and seeing where it takes you.”

Links :

Tuesday, January 23, 2018

Here’s where the Arctic’s wildlife will make its last stand

From National Geographic by Tim Folger

Forecasters say the region’s sea ice will dwindle to a strip above Greenland and Canada.
There, polar bears and others will fight to survive.

We see evidence of the kill first: a shockingly broad spread of scarlet, probably the blood of a ringed seal, on snow-covered sea ice.
Then the polar bear appears.
She’s big, maybe 500 pounds, trailed by a single cub.
They’ve just jumped into a lead—a long fissure of open water in the frozen sea.
In seconds they’re out of the water again, running across the ice, spooked by the approach of our helicopter.
Prolonged running can harm polar bears: Fat and fur insulate them so well they risk overheating.
François Létourneau-Cloutier, our 33-year-old Québécois pilot, takes us higher, and the mother and cub slow to an amble.

 Off the north coast of Canada’s Baffin Island, a June sun transforms snow and ice into limpid pools of turquoise.
The Arctic’s perennial sea ice cover—the ice that survives the summer melt season—has shrunk dramatically
photograph : Brian Skerry

After following them for several minutes, Létourneau-Cloutier sets the helicopter gently onto the ice a few hundred feet away and cuts the engine.
The mother rises on her hind legs, assessing our 35-foot-long flying machine with the unruffled gaze of the Arctic’s top predator; the cub remains on all fours behind her.
For a few timeless moments we savor the scene—bears against an otherwise empty immensity of snow and ice, countless shallow pools of meltwater reflecting a high summer sun ringed by faint halos of red and blue.
Then, with a frenzied whine, the helicopter’s rotor blades break the spell, and we lift off, veering southwest toward our campsite on the northernmost tip of Baffin Island, Canada, about 700 miles north of Hudson Bay.

 On a nearly ice-free August morning, walruses flop ashore on Devon Island, north of Baffin. Walruses dive as deep as 300 feet to feed on clams and other bottom dwellers.
In between dives they rest on sea ice; dry land is a less convenient substitute.
photograph : Florian Ledoux

Within a few decades such vistas are unlikely to exist, at least not here, during summer.
As the planet heats up, the summer sea ice and all the superbly adapted life it supports—the bears, the seals, the walruses, the whales, the Arctic cod, the crustaceans, the ice algae—may well vanish around Baffin.
As we fly over the vast frozen expanse, it almost strains belief to think that we’re witnessing—and with the rest of humanity, helping to cause—its demise.
In the 1980s satellite data showed that Arctic sea ice extended on average across nearly three million square miles at the end of summer.
Since then more than a million square miles has been lost—an area roughly the size of Alaska, Texas, and California combined.

Climate models suggest that by the 2050s, less than 200,000 square miles of perennial sea ice will remain.
The good news, such as it is: What’s left will collect in a compact region, not here but farther north, above Greenland and Canada’s Ellesmere Island.
That shrunken redoubt will be the last stand for many of the Arctic’s wild things.

 A pod of beluga whales swims through Lancaster Sound north of Baffin Island.
The whitest ones are adults that have already molted: Every summer belugas seek out shallows where they can rub off their old skin against gravel and sand.
Photograph : Paul Nicken

“The animals that depend on the edge of the sea ice for a living will be congregating there in the summer,” says marine ecologist Enric Sala, leader of the National Geographic Society’s Pristine Seas project.
“It will be like one of those watering holes in Africa where everybody shows up.”

Sala has come to Baffin with divers and filmmakers to document the icy world that’s doomed here—and to make the case for preserving the “last ice” farther north.
Since he started Pristine Seas a decade ago, the project has helped protect more than three million square miles of ocean.
But preserving the remnants of Arctic ice, which will require the cooperation of Greenland and Canada, will be its most ambitious undertaking.

It’s also the most urgent.
“The Arctic is changing faster than anything else,” Sala says, and as the ice goes away, shipping, fishing, and oil and gas development may intrude.
If sea ice and its denizens are to be protected, it must happen before exploitation of Arctic resources becomes unstoppable.
With the last-ice project, Sala says, “we’re looking 25 years ahead.”

In satellite photos, and perhaps in our imaginations, the icescape glazing the top of our world appears static, like a featureless white continent, permanent and immobile.
Actually it’s a jostling mass of ice floes that, propelled by winds and currents, drift from one side of the Arctic to the other in journeys lasting years.

 Dripping wet, a polar bear climbs onto an ice floe in northernmost Hudson Bay. Polar bears perch on sea ice to ambush seals—the source of 90 percent of their calories—when the seals surface. National Geographic Explorer-in-Residence Enric Sala is leading an effort to preserve some of the bears’ dwindling habitat.
“In Russia we found bears stuck on islands eating grass and seabirds,” he says.
Photograph : Paul Souders

“People don’t understand the Arctic,” says Stephanie Pfirman, an oceanographer at Barnard College and Columbia University.
“They think of it as an ice cap.
They think that it’s rigid and that when it melts it’s just melting back on the edges.
They don’t think of this dynamic aspect of it.”

In 2010 Pfirman was part of a team that identified the most likely location for the Arctic’s last summer sea ice, work that has helped guide the Pristine Seas effort.
Comparing a variety of computer models and satellite data, she and her colleagues found that winds and currents conspire to funnel drifting sea ice from all over the Arctic onto the northern edges of Greenland and the Canadian Arctic Archipelago—a region of spectacular fjords and more than 36,000 islands, including Ellesmere and Baffin.
Year after year, massive ice floes stack up in that relatively calm zone.
Some of the ice there is decades old and more than 80 feet thick.

Pfirman and her colleagues realized that by mid-century, this frigid haven would hold the Arctic’s only year-round ice.
Their discovery was far from obvious.
In some earlier climate models, Pfirman says, the Arctic’s ice cover simply retreated evenly along its southern flank as the planet warmed, ultimately settling right around the North Pole.
“That makes no sense at all, though,” she says.
“There’s no reason for ice to congregate at the North Pole.
It’s going to keep moving until it hits something.”

 Pants made of polar bear fur identify Naimanngitsoq Kristiansen, an Inuit man from Qaanaaq in northwestern Greenland, as a seasoned hunter.
With sea ice thinning every year, his dogsled journeys have grown increasingly hazardous.
Photograph : Paul Nicken

Despite the steep decline in store over the next several decades, a long, narrow band of perennial ice will persist late into this century.
If we can end our reliance on planet-heating fossil fuels, it could survive even longer—into a time when, just maybe, we’ll figure out how to remove enough carbon from the atmosphere to cool the planet again.
“The ice models don’t drop down to zero,” Pfirman says.
“Some people say it’s hopeless, because we’re on a trajectory where ice is going to be lost.
But if you look at the climate models, it drops down precipitously, and then it has this long tail, which gives us some time to act and potentially mitigate the warming.”

The ice that does remain in the Arctic may provide a stable environment, albeit a compact one, for organisms that depend on ice.
“For people concerned about habitats, it’s not that you will sometimes have the summer ice off the coast of Siberia and sometimes have the ice in the Beaufort Sea,” Pfirman says.
“Because you couldn’t sustain a habitat if that ice was moving all around.
It’s actually pretty consistently going to be banked up off the coastlines of Greenland and Canada.”

“This is a newcomer,” says Theo Ikummaq, stooping and pointing to a delicate green shoot on the rocky beach near our campsite.
Ikummaq, a 60-year-old native of Igloolik, an island off of Baffin, is a guide and adviser for our expedition.
It’s a cold and foggy June afternoon; the inlet we’re walking along is still frozen.
Clouds have covered the sun for days now.
Ikummaq carries a rifle over his shoulder in case we need to scare away polar bears.
We’ve already spotted the tracks of one in the sand only a few hundred yards from our camp.

The little green shoot, maybe a couple of inches high, has no name in the Inuit dialect spoken in this part of the Arctic.
Ikummaq doesn’t recognize it; he knows only that it’s another example of how the land and life are changing here.
During our walk we’ve passed what Ikummaq says are new features in the landscape: large circular sinkholes, created by thawing permafrost.

 Narwhals mingle in Lancaster Sound, off Baffin Island.
They winter in ice-covered waters, feeding on halibut.
The corkscrew tusk, a canine that grows up to nine feet long, may serve to impress females, which rarely have one.
Photograph : Paul Nicken

Later that day, in the big tent where we have our meals, Ikummaq tells me the names for a few Arctic animals.
An aarluk—“kills everything”—is a killer whale; a tingugliktuq—“bad liver, don’t eat”—is a horned lark.
But some animals, such as robins, are so new to the Arctic that Ikummaq, at least, doesn’t know names for them.

With global warming, plant and animal species from the south have started to move north.
It’s a trend that will only accelerate, says Brendan Kelly, a biologist at the University of Alaska in Fairbanks.
As the habitat for Arctic wildlife shrinks, the animals that survive are likely to undergo profound changes.
Diverse species will be thrust into closer contact than ever before.

“There’s the potential for a massive scrambling of genes in the whole Arctic Ocean,” Kelly says.
“We did a survey of marine mammals and came up with 34 species that are capable of hybridizing.” For reasons that scientists don’t yet understand, marine mammals have tended to retain the same number of chromosomes—a key requirement for hybridization—as they diverged into different species and even genera.

“So you end up with things that you would otherwise say are different genera, but are in fact able to produce fertile hybrid offspring,” says Kelly.
“An example would be harp seals and hooded seals, which we classify as different genera—but we’ve seen them hybridize in the wild.
There is some evidence of a hybrid between belugas and narwhals.” Pizzlies—crosses of grizzlies and polar bears—already roam the Arctic.
Genetic studies show that polar bears began diverging from grizzly bears within the past 500,000 years.
Global warming threatens to reunite the two species.

“We could lose polar bears,” Kelly says.
“They might be reabsorbed into the grizzly bear genome out of which they came.
We’re not just talking about ecological change.
We’re talking about evolutionary change—really sped up.”

The end result, says Kelly, is likely to be a tremendous, irreversible loss of genetic diversity.
But even if that weren’t the case, the Arctic’s wildlife would still be in trouble.
“We’re changing the habitat so fast that even if they have the genetic diversity to respond, they may not have the time.” For some of the world’s iconic species, the last-ice region could make the difference between survival and extinction.

 Walruses dive and court near the Norwegian island of Spitsbergen.
Their skin, light gray or brown in frigid water, reddens when the blubbery animals haul out on land and blood flushes through their thick outer layers of skin.
Photograph : Paul Souders

“Peaceful, isn't it?” Enric Sala is smiling as he joins me on the beach in front of our camp’s double row of two dozen orange tents.
We’re looking east across the frozen reaches of Navy Board Inlet toward Bylot Island, several miles away.
Covered with mountains and glaciers, a refuge for denning polar bears and hundreds of thousands of nesting birds, it’s larger than the big island of Hawaii.
The sun is out, the weather has finally lifted, and there’s barely any wind.
After more than a week of waiting, Sala and his team of divers are eager to explore some open water around a couple of small islands off Bylot’s western shore.
In a few weeks, algae will be in full bloom, the water will cloud, and underwater filming opportunities will vanish.
But now, the sea here is just beginning to blaze with life.

“Sunlight is like a lighter for this ecosystem; it’s why we’re here now,” says Manu San Félix, a diver and photographer who has joined us on the beach, wearing his dry suit.
Over the next few days, if the weather holds, he, Sala, and other expedition members will record the beauty of what will be lost if we fail to protect the Arctic’s last ice.

The harder work, more arduous even than diving in freezing water, will take years: persuading governments to cooperate to save a region that extends across borders.
Preserving the last-ice region itself won’t be enough; because ice migrates long distances, its sources eventually will have to be protected as well.
Right now, for example, Siberian ice contaminated with nickel and lead from the Russian industrial city of Norilsk—one of the world’s most polluted places—sometimes drifts into the Canadian Arctic.
There it poisons the food web as it melts.

“It’s a good sign that we are seeing narwhals, belugas, and polar bears,” says San Félix.
It means the food chain here is still healthy.
We talk about a pod of bowhead whales that were spotted during a helicopter flight the other day and about how their huge heads enable them to smash through two feet of ice.
Bowheads can live 200 years or more.
(One way their age has been determined is by carbon-dating old harpoon points embedded in their bodies.) The oldest of them now, says San Félix, might have been born when Napoleon was still alive.
“Imagine!” he says.
“That calf we filmed might be here in 2215!”

If we’re lucky, that is, and foresighted enough.
Says Sala: “This is not a simple, linear story where we know how it ends.”

Links :

Monday, January 22, 2018

Undersea maps reveal Great Barrier Reef in unparalleled detail

A visualisation of the Great Barrier Reef based on a joint project between Geoscience Australia, James Cook University and the Australian Hydrographic Service.
The visualization shows the Great Barrier Reef sea floor in unprecedented detail.
The bathymetry dataset is produced at 30 metre resolution using a combination of historical and new sea floor mapping data and is a vast improvement on the previously available 250 metre resolution dataset.
The new dataset covers an area of 1.7 million square kilometres and provides a unique understanding of the structure of the Reef.

From Geosciences AU

High-resolution sea floor maps released today show 1.5 million square kilometres of Australia's iconic Great Barrier Reef in unprecedented detail.
The maps are the product of a collaborative project between James Cook University, Geoscience Australia and the Australian Hydrographic Service.

This is the first high-resolution mapping of the sea floor of the entire Great Barrier Reef.
Attribution: "Australian Hydrographic Service, Geoscience Australia, James Cook University" 
JCU's research leader, Dr Robin Beaman, initiated the project in 2009.
"The Great Barrier Reef data is the first in a series of '30-metre' datasets that will be released as part of this project. This represents the highest resolution depth model of the Great Barrier Reef, to date," he said.
"We're using cutting-edge scientific techniques to combine historical and newly-acquired bathymetry (undersea mapping) data of the entire northern coastline of Australia," he said.
"Along with the quality of the new data we've acquired, we've also been able to access undersea mapping data collected over the past few decades by government and university research programs."
"Our partners at Geoscience Australia will be releasing open source data of large parts of the coastline as it becomes available. The grids we've built will enhance our understanding of the terrain of the sea floor in shallow waters off the coast of northern Australia."

 new 30 m bathymetry gridding
Attribution: "Australian Hydrographic Service, Geoscience Australia, James Cook University"

Chief of Geoscience Australia's Environmental Geoscience Division, Dr Stuart Minchin, said he was pleased that his team was able to get on board and support this important project with such wide-ranging potential.
"The dataset we've released today maps the entire Great Barrier Reef with data that is around eight times higher resolution than what was available previously. This is a vast improvement and it creates huge opportunities for the scientific and policy community, most importantly for the environmental management of the reef," Dr Minchin said.
"Having greater knowledge of the shape of the reef will be a critical tool for the government agencies responsible for its protection.

This gives those organizations a far more detailed view of the reef with which they can identify new reef structures and coral formations.
"Bathymetry data is also an important input for oceanographic modelling which can be used to improve our knowledge of climate change impacts, marine biodiversity and species distribution. It will also support modelling of tides and ocean currents.
"We've been able to support the team at JCU, who are specialists in this kind of marine research by contributing our resources and expertise to the project. We've also worked with the Australian Hydrographic Service to bring their vast stores of marine mapping data into the project as well.
"Collaborating with these organisations over the past four years has seen us map the entire northern Australian coastline, including the Great Barrier Reef. We saw the value in JCU's work and the potential of these high-quality datasets to provide greater certainty on Australia's maritime boundaries for government and other maritime operators."

 Northerly view of Hook and Line Reefs off Airlie Beach.
Depths are coloured red (shallow) to blue (deep), over a depth range of 84 metres. 
Attribution: "Australian Hydrographic Service, Geoscience Australia, James Cook University"
Hook reef with the GeoGarage platform 
(AHS nautical raster charts overlaid upon Google Maps satellite imagery)

Easterly view of Sudbury and Moore Reefs off Cairns.
Depths are coloured red (shallow) to blue (deep), over a depth range of 100 metres.
Attribution: "Australian Hydrographic Service, Geoscience Australia, James Cook University"

Moore & Sudbury Reefs with the GeoGarage platform

(AHS nautical raster charts overlaid upon Google Maps satellite imagery)

Westerly view of One Tree and Heron Reefs off Gladstone.
Depths are coloured red (shallow) to blue (deep), over a depth range of 100 metres.
Attribution: "Australian Hydrographic Service, Geoscience Australia, James Cook University"
 Wistary, Heron, Sykes, One Tree Reefs with the GeoGarage platform 
(AHS nautical raster charts overlaid upon Google Maps satellite imagery)

Dr Beaman said he was pleased that the Great Barrier Reef bathymetry was the first dataset to be released, given the reef's unique marine environment.
"Being based in northern Queensland, JCU prides itself on being at the forefront of scientific research when it comes to the reef; we are committed to providing government and researchers with information that will ultimately help protect it," he said.
The series of datasets produced through this project will provide a detailed view of the marine geography of Australia's northern coastline, providing greater certainty on the location and extent of the country's maritime boundaries.
The datasets will support safety of life at sea, the enforcement of law, and government operations.

Case study: Captain Cook and the Endeavour

When Captain Cook's ship the Endeavour first entered the Great Barrier Reef on 20 May 1770, Cook found an 'insane labyrinth' of coral.
The ship ran aground on what is now called Endeavour Reef.
Captain Cook made painstaking maps of the region, such as this section from Cape Tribulation to Cape Flattery.

Captain Cook's map of the Great Barrier Reef, from Cape Tribulation to Cape Flattery

 Cape Tribulation to Cape Flattery with the GeoGarage platform 
(AHS nautical raster charts overlaid upon Google Maps satellite imagery)

In 2009, we had 250 m bathymetry grids of this area:

250 m bathymetry data of the Great Barrier Reef, from Cape Tribulation to Cape Flattery

The new 30 m bathymetry grids of this region show it in extraordinary detail.

30 m bathymetry data of the Great Barrier Reef, from Cape Tribulation to Cape Flattery

Links :

Sunday, January 21, 2018

2017: one year time lapse of surface winds over the South America and the Atlantic

This animation shows a full, one year time lapse animation of surface winds from Jan 1, 2017 until Jan 1, 2018.
The data come from NWS's GFS numerical weather model 
Blue colors represent slower winds.
Greens and yellows are faster winds.
Streamlines show the direction of the wind in each frame of the animation.
A few things to notice:
1. Look for the trade winds. Can you find the Inter-tropical Convergence Zone?
2. Where are the "Roaring Forties" and why do they occur?
3. What occurs regularly in the North Atlantic / Caribbean / Gulf of Mexico, but very rarely in the South Atlantic? (No occurrences in 2017.)