4 nautical raster charts updated
see GeoGarage news
Thursday, December 14, 2017
These imaginary islands only existed on maps
The island of Hy-Brasil is featured on this 16th-century map but isn't actually real.
From National Geographic by Simon Worall
Some islands, like King Arthur’s Avalon, were pure legend.
Others were mistakes or outright hoaxes.
In the age of GPS and Google Maps, it is hard to believe that maps can include places that don’t exist.
But author Malachy Tallack argues that maps are as much “a cartography of the mind” as they are a way to figure out where we are.
In his new book, The Un-Discovered Islands, Tallack takes readers on a journey to imaginary places—mythic islands, mapmakers’ mistakes, mirages, and outright hoaxes.
When National Geographic caught up with Tallack on a Greek island (a real one), he explained why some islands blur the line between life and death; how others have moved about on the maps; and why we’re living in an era of un-discovery.
You write, “For as long as people have been making stories, they have been inventing islands.” Explain why that is—with some examples.
It is natural for us, standing on the shore looking out to the horizon, to imagine there are places out there we cannot see.
Many cultures have such places that are important parts of their cultural traditions.
One of the best known is Hawaiki, which the Maori people believe to be not just their geographical origin, but also their spiritual origin—the place they were born from and would die into.
These islands that blur the boundaries between life and death seem to have existed in all cultures.
The ancient Greeks imagined a place called the Islands of the Blessed, which in some ways resembled the idea of the Christian heaven, except that this was paradise on Earth where the chosen few would go to when it came time to die.
That idea then migrated into Celtic mythology.
The most famous example is Avalon, where King Arthur supposedly went at the end of his life.
Another category you write about is what you call “ex-isles.” What makes an island disappear?
All of the islands in this book are, I suppose, ex-isles, in that they were places that were believed in at one point, but which are no longer found on the map.
The most common reason was that sailors would make errors.
They would think they were seeing an island whereas, in fact, it was a mirage, they were in the wrong place, or the conditions were so terrible that it wasn’t what they thought it was.
The oceans became populated by islands that, in fact, turned out not to exist.
It’s much easier to discover an island than it is to un-discover one because you have to go back and check it is not actually there.
During the Age of Discovery, explorers were also tempted to invent islands, which they would often name after rich patrons, in the hope of squeezing a bit of extra money for further exploration.
Insulae Hebrides” (the Hebrides Islands), "Farne" (the Faroes, or perhaps Fair Isle - where Fair Isle sweaters come from), Hetlandia (the Shetlands), and Orcades (the Orkneys).
Map of the Island of Thule, (spelled “Tile” on this map) in Scotland, by Olaus Magnus, 1539.
This is a detail of his much larger Carta Marina – a map of the ocean showing the Northern Lands.
For many years, it was commonly thought that Thule was one of the Hebrides Islands in Scotland.
Notice the whales (Balena, Orca) in the foreground.
The Hebrides are still famous for their whales, seals, and sea otters, and there are lots of opportunities for whale-watching boat trips.
Take the island of Thule.
It was supposedly discovered by Greek explorer Pytheas, and became part of the Greek idea of what lay in the north.
Later, it became absorbed by the Romans, who believed that the Shetland Islands were Thule.
Later on, people believed that Iceland or Norway was Thule.
Eventually, the word became not a place but an idea of northern-ness; somewhere that was extreme and far away.
It became part of the cartography of the mind more than the cartography of the map.
A detail of Septentrionalium Regionum [Region of the Northern Sea] by Abraham Ortelius
from his atlas Theatrum Orbis Terrarum [Theater of the World], Holland, 1570.
Some people argue that it was the Irish, not the Norse, who first set foot in North America.
Is there any truth to that?
In theory, it is possible.
St.Brendan is the person sometimes credited with having done that, though the stories about him vary somewhat in the telling.
The idea is that he set out to sea from Ireland and travelled to numerous places around the north Atlantic.
Some of the stories are obviously fantastical, with demons, dragons, and sea serpents.
But there are other parts that seem realistic.
They talk about islands of smoke and fire, which could be volcanoes.
Other parts seem to refer to icebergs.
But the notion that a monk made it all the way to North America and back seems, to me, extraordinarily unlikely.
Hy-Brasil: Mapping a Mythical Island
Hy-Brasil is one of the most famous and, in some ways, complicated of undiscovered islands.
It has nothing whatsoever to do with the country Brazil.
It’s long been thought that this island was part of Irish mythological tradition.
Certainly, there are numerous islands within Celtic and Irish tradition that can sometimes be seen, and sometimes disappear.
Hy-Brasil was thought of be one of those.
More recent studies have shown that Hy-Brasil didn’t appear in Irish mythology until the 19th century, hundreds of years after it was first located on a map.
At that time, there were numerous other places called Brasil.
The name referred to a kind of red dye, which was very valuable and one of the things explorers were looking for.
Hy-Brasil, which appeared on maps off the southwest coast of Ireland, may actually have come from rumors of the North American continent spread amongst European sailors.
It was then later absorbed into the Irish mythological tradition, which is the opposite direction from what you would expect.
My favorite story in the book is of Princess Caraboo and the island of Javasu.
Give us a synopsis.
That is also my favorite.
[Laughs] It is an odd story and a strange island because, unlike most of these places, it never appeared on a map.
The story begins in the south of England, in the early 19th century, when a woman appeared on a doorstep, dressed and behaving slightly oddly.
Nobody knew who she was.
She didn’t speak English and nobody could understand what she said.
She was taken in by the family of the local magistrate, Samuel Worrall, who looked after her and tried to find out who she was.
Eventually, they located a man who said he could understand what she was saying.
He said that the woman, who called herself Caraboo, had come from the island of Javasu, in the Far East, and was a princess.
But it turned out this was not the case.
She was actually a woman called Mary Wilcox, from Devon, who had had a difficult life.
She probably had mental health problems and had essentially retreated from the world.
But she attracted wealthy people from all over England because, at that time, the British were obsessed with the glamour of the Orient.
There were newspaper stories; her portrait was painted.
And that turned out to be her downfall because somebody recognized her in the newspaper and realized she was not who she was thought to be.
She is generally portrayed as a hoaxer.
But the real hoaxer was the man who pretended to understand what she was saying and invented all of these details about Javasu and the life of this supposed princess, Caraboo.
In the end, she was deported to the U.S.
For a time, she managed to make a living off her fame, but eventually she returned to England and lived in poverty.
She is buried in Bristol in an unmarked grave.
But some years ago, they made a movie about her.
In his only novel, The Narrative of Arthur Gordon Pym of Nantucket, Edgar Allan Poe incorporates one of the best-known stories of fictional isles, the Auroras, which you call “among the most inexplicable of phantom islands.” Why?
Most phantom islands were seen once and never seen again.
A sailor thought he saw an island and later was found to be wrong.
The Auroras break that mold because they were seen not just once, but seven or eight times, between the Falkland Islands and South Georgia.
One of the ships that saw the Auroras was a Spanish research vessel, which went there specifically to find and survey the islands.
So it was very strange that, after that time, nobody else could find them.
They seem to have completely disappeared.
The best explanation for it is that all these sailors and ships, including the highly skilled Spanish surveyors, were somehow mistaken by conditions, potentially by icebergs, in that region.
It’s one of several places where none of the explanations seem quite good enough.
Nobody knows exactly what happened to the Auroras.
Some islands are the result not of cartographic error but downright fraud.
Tell us how one phantom island played havoc with the peace treaty between the United States and Britain.
When the Treaty of Paris was drawn up in 1783, a big part of it was finalizing the borders between the new country, the U.S., and its neighbors.
Most of those borders were fairly simple.
But in the north, around the Great Lakes, it was more complicated geographically and politically.
The treaty locates the border as running through Lake Superior, where it goes north of the isles Royale and Philippeaux.
Charlevoix map of the Great Lakes, 1744
Unfortunately, it was found several decades later that Isle Philippeaux did not exist.So, in the original treaty that created the U.S. as a country, there was a place that did not exist.
Isle Philippeaux, along with several other islands within Lake Superior, was invented by a priest, who named them after a rich French politician, with the intention of getting more money.
The islands known as Los Jardines stubbornly remained on maps for 400 years, even though they never existed.
In that time, they even moved about, didn’t they?
Like the Auroras, it’s hard to explain how Los Jardines, or Los Buenos Jardines, came to exist for such a long time.
They were first reported in 1529 by Alvaro de Saavedra Ceron, in the Western Pacific, not far from New Guinea.
He described 10 low-lying islands or atolls, which he named Los Buenos Jardines, and these islands remained on the map for a long time.
Two hundred or so years later, they moved northwards but there is no good explanation for why that happened.
Perhaps a cartographer made an error or a sailor decided he had seen them elsewhere.
It was not until 1973 that the International Hydrographic Organization finally removed them from the charts.
Deleted islands : once upon a time, Captain Sir Frederick Evans a rigorous ocean surveyor wiped 123 islands off the map
Today, it’s very difficult for us to imagine the lack of knowledge that many explorers had.
They had no accurate way of measuring longitude until the mid-18th century, so they weren’t always sure where they were.
In the Pacific Ocean, particularly, many islands appeared on maps but later had to be removed.
You call the 20th century “a time of un-discovery.” Tell us the story of Sandy Island and why you believe it is important that some places remain mysteries.
Sandy Island is the most recent island to be un-discovered, in late 2012.
An Australian research vessel noticed discrepancies between the navigational chart and the systems they had on board, some of which showed Sandy Island in the region between Australia and New Caledonia, and some of which did not.
They decided to have a look for themselves but found there was no such island, neither above nor beneath the surface.
But Sandy Island still appeared on all kinds of charts and even Google Maps and Google Earth.
We assume digital navigation is perfect, that there are no mistakes, but there can be and this is the most famous example.
It was widely reported around the world and people became quite excited about the idea of an island that both did and did not exist.
The reason, I think, is that, as the Age of Discovery came to a close, we lost some of the sense of mystery about the world that we had always had.
To find a place that broke all the rules, which appeared on a map, yet wasn’t actually there, was an exciting idea.
Sandy Island seems to speak to our deep desire for there to still be mysterious places out there.
What I’ve tried to do is recreate that sense of the mystery of geography.
Links :
- National Geographic : How explorer Robert Peary discovered a continent that wasn’t there
- Crossing the Ocean Sea : The Mythical Atlantic Islands
- Atlas Obscura : How to Put a Fake Island on the Map
- Wikiwand : List of fictional islands
- Wikipedia : Phantom island
- GeoGarage blog : South Pacific Sandy Island 'proven not to exist' / How a fake island landed on Google Earth / Mystery of the phantom islands solved: Lands that ... / About the Null island at 0°0'0" N 0°0'0" E / 657 new islands discovered worldwide / Lost Islands: the story of Islands that have vanished ... / Improbable South Pacific reefs / Hy-Brasil, the other Atlantis /
Wednesday, December 13, 2017
NASA shows new Tongan Island made of tuff stuff, likely to persist years
Hunga Tonga-Hunga Ha’apai as seen in September 2017
see on Google Maps
see on Google Maps
Image: 2017 DigitalGlobe
From Earther by Maddie Stone
Hunga Tonga-Hunga Ha’apai wasn’t supposed to last.
The cloud of volcanic ash that became island-shaped in early 2015, about a month after an underwater volcano erupted in the South Pacific Kingdom of Tonga, was expected to be washed away by the ocean in three to four months.
Hunga Tonga with the GeoGarage platform (Linz chart)
And according to new research led by NASA, it could last for decades more.
“We haven’t had an island like this sustain itself in 50 years,” Jim Garvin, chief scientist of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, told reporters at a press conference at the American Geophysical Union meeting in New Orleans yesterday.
In late December 2014 into early 2015, a submarine volcano in the South Pacific Kingdom of Tonga erupted, sending a violent stream of steam, ash and rock into the air.
When the ash finally settled in January 2015, a newborn island with a 400-foot summit nestled between two older islands – visible to satellites in space.
The newly formed Tongan island, unofficially known as Hunga Tonga-Hunga Ha'apai after its neighbors, was initially projected to last a few months.
Now it has a 6- to 30-year lease on life, according to a new NASA study.
As Garvin explained, the shallow submarine eruption that birthed Hunga Tonga-Hunga Ha’apai was special.
Not only did the eruption spew lava, “it also produced some of the explosive magma water interactions that were the hallmark of the eruption that produced Surtsey,” an island off the coast of Iceland that formed in the 1960s and has persisted to this day.
Hunga Tonga-Hunga Ha'apai is the first island of this type to erupt and persist in the modern satellite era, it gives scientists an unprecedented view from space of its early life and evolution.
The new study offers insight into its longevity and the erosion that shapes new islands.
Understanding these processes could also provide insights into similar features in other parts of the solar system, including Mars.
Garvin believes Hunga Tonga-Hunga Ha’apai has outlived its expected lifespan because of chemical interactions between warm seawater and volcanic material, which caused its rocky shorelines to harden shortly after the eruption.
If this hunch is correct, it would make the new island the first long-lived “surtseyan” island of the satellite record.
Scientists are now monitoring the volcanic island closely, using monthly satellite images to track its changing coastlines, and nearshore measurements with research vessels to map the seafloor.
They’ve watched it change dramatically.
Initially, Hunga Tonga-Hunga Ha’apai was fairly oval-shaped, rising 400 feet from its coastlines to a central tuff cone.
Over time, the entire island has become thinner and more stretched out as material erodes off the tuff cone and collects along the coastlines.
The first big change came in April 2015, when satellite images revealed that the cliffs marking the southern rim of the crater had collapsed.
A few weeks later, the last remnants of the crater wall were gone, opening a central lake to the ocean.
A high-resolution satellite image of Hunga Tonga-Hunga Ha’apai right after it formed, in January 2015.
Image: Pleiades-1A ©2015 CNES Distribution Airbus DS
At that time, Garvin explained, there was a risk of ocean waves impacting the tall cliffs on the inside of the crater, accelerating the cone’s collapse.
But within a few more weeks, a sandbar had formed to protect the crater lake.
That feature has persisted until this day.
The other major change has been the growth of a large peninsula to the northeast.
By April 2015, that peninsula connected Hunga Tonga-Hunga Ha’apai to another nearby island.
It has continued to widen over time.
To their surprise, the researchers are finding that the total volume of the island, as estimated using elevation models, has remained fairly stable after the first few months.
Hunga Tonga-Hunga Ha’apai is now expected to survive for anywhere from six years to about three decades, depending on how quickly the tuff cone at its center is destabilized.
“This island is fighting for its life,” Garvin said.
“And our predictions suggest we’ve got potentially another decade [or more] to watch this thing evolve from space.”
Changes to Hunga Tonga-Hunga Ha’apai’s shoreline over time are overlain atop a September 2017 satellite image.
Image: NASA/©DigitalGlobe
In addition to just being cool as hell, tracking this island’s evolution could help us understand the history of other worlds, namely, our friendly neighborhood Red Planet.
As Garvin explained, Mars features fields of small volcanoes “very similar to Hunga Tonga-Hunga Ha’apai in appearance, but we don’t know the context in which they formed.”
in brown, erosion areas
NASA 2017 Digital Globe
The question now is, are the different stages of the Earthly island’s evolution evident in volcanic features on Mars?
And if so, does that tell us something about when Mars last had water, and how deep and widespread that water was?
“We think [this is] a real opportunity for learning,” Garvin said.
Digital elevation model showing the topography of Iceland’s Surtsey island (left) and Hunga Tonga-Hunga Ha’apai (right).
Image: NASA This has been your periodic reminder that Earth is a dynamic, amazing world, and we’re damn lucky to live on it.
Links :
- NASA : NASA shows new Tongan Island made of tuff stuff, likely to persist years / New Island Made of Tuff Stuff / Facebook NASA / The Birth of a New Island: Press Materials
- The Guardian : Pacific pop-up: island that rose from the ashes might last 30 years
- DailyMail : The remarkable island born from an underwater volcanic eruption: NASA reveals new Pacific island Hunga Tonga-Hunga Ha'apai formed in 2015 and could survive for up to 30 years
- National Geographic : New Volcanic Island May Survive Much Longer Than Expected
- GeoGarage blog : Image of the week : birth of a new island in Tonga / New volcanic island unveils explosive past
Tuesday, December 12, 2017
Seven charts that explain the plastic pollution problem
Dr Lucy Quinn from the British Antarctic Survey looks at plastic ingested by albatross.
From BBC by Alison Trowsdale, Tom Housden and Becca Meier.
Design by Sue Bridge and Joy Roxas.
Marine life is facing "irreparable damage" from the millions of tonnes of plastic waste which ends up in the oceans each year, the United Nations has warned.
"This is a planetary crisis... we are ruining the ecosystem of the ocean," UN oceans chief Lisa Svensson told the BBC this week.
But how does this happen, where is most at risk and what damage does this plastic actually do?
Why is plastic problematic?
Plastic as we know it has only really existed for the last 60-70 years, but in that time it has transformed everything from clothing, cooking and catering, to product design, engineering and retailing.
One of the great advantages of many types of plastic is that they're designed to last - for a very long time.
And nearly all the plastic ever created still exists in some form today.
In July a paper published in the journal Science Advances by industrial ecologist Dr Roland Geyer, from the University of California in Santa Barbara, and colleagues, calculated the total volume of all plastic ever produced at 8.3bn tonnes.
Of this, some 6.3bn tonnes is now waste - and 79% of that is in landfill or the natural environment.
This vast amount of waste has been driven by modern life, where plastic is used for many throwaway or "single use" items, from drinks bottles and nappies to cutlery and cotton buds.
Four billion plastic bottles...
Drinks bottles are one the most common types of plastic waste. Some 480bn plastic bottles were sold globally in 2016 - that's a million bottles per minute.
Of these, 110bn were made by drinks giant Coca Cola.
Some countries are considering moves to reduce consumption.
Proposals in the UK include deposit-return schemes, and the improvement of free-drinking water supplies in major cities, including London.
So how much plastic waste ends up in the sea?
It's likely that about 10m tonnes of plastic currently ends up in the oceans each year.
In 2010 scientists from the National Center for Ecological Analysis and Synthesis and the University of Georgia in Athens estimated the figure as 8m tonnes, and forecast that to rise to 9.1m tonnes by 2015.
The same study, published in the journal Science in 2015, surveyed 192 coastal countries contributing to ocean plastic waste, and found that Asian nations were 13 of the 20 biggest contributors.
Plastic waste accumulates in areas of the ocean where winds create swirling circular currents, known as gyres, which suck in any floating debris.
There are five gyres around the globe, but the best known is probably the North Pacific gyre.
It is estimated debris takes about six years to reach the centre of the North Pacific gyre from the coast of the US, and about a year from Japan.
All five gyres have higher concentrations of plastic rubbish than other parts of the oceans.
They are made up of tiny fragments of plastic, which appear to hang suspended below the surface - a phenomenon that has led it to being described as plastic soup.
And the hard-wearing qualities of most plastics means that some items can take hundreds of years to biodegrade.
However, there are moves to clean up the North Pacific gyre.
An operation led by a non-profit organisation Ocean Cleanup is due to begin in 2018.
The Marine Conservation Society found 718 pieces of litter for every 100m stretch of beach surveyed during their recent Great British Beach Clean Up.
That was a 10% increase on last year.
The origin of a lot of the litter is difficult to trace, but the public contributes about 30%.
"Sewage-related debris", or items flushed down toilets that should have been put in the bin, amounted to some 8.5%.
For sea birds and larger marine creatures like turtles, dolphins and seals, the danger comes from being entangled in plastic bags and other debris, or mistaking plastic for food.
Turtles cannot distinguish between plastic bags and jellyfish, which can be part of their diet.
Plastic bags, once consumed, cause internal blockages and usually result in death.
Larger pieces of plastic can also damage the digestive systems of sea birds and whales, and can be potentially fatal.
Over time, plastic waste slowly degrades and breaks down into tiny micro-fragments which are also causing scientists concern.
This can result in malnutrition or starvation for the fish, and lead to plastic ingestion in humans too.
The effect on humans of eating fish containing plastic is still largely unknown.
But in 2016 the European Food Safety Authority warned of an increased risk to human health and food safety "given the potential for micro-plastic pollution in edible tissues of commercial fish".
Links :
- The Times : Ten rivers carry 90% of plastic found in oceans
- FT : The plastics suffocating life within our oceans
- Treehugger : UK celebrates first "Plastic Free Coastline" community
- GeoGarage blog : 'Planet is doomed' unless ocean health improves ... / New study helps explain how garbage patches form in ... / Scientists and engineers turn ocean plastic into new ... / Our seas have become a plastic graveyard - but can ... / We can solve the ocean plastic problem / 'Biodegradable' plastics are a big fat lie / Study finds rising levels of plastics in oceans / ...
Monday, December 11, 2017
Subscribe to:
Posts (Atom)