New Greenland maps show more glaciers at risk

UCI’s BedMachine ice mapping technique enabled the creation of a three-dimensional image of a portion of the northwest coast of Greenland.

Ocean bathymetry is shown in blue and ice surface topography are displayed in white and orange.

Mathieu Morlighem / UCI

From UCI

UCI-created high-resolution charts will inform future ice and sea level forecasts

New maps of Greenland’s coastal seafloor and bedrock beneath its massive ice sheet show that two to four times as many coastal glaciers are at risk of accelerated melting as had previously been thought.

Researchers at the University of California, Irvine, NASA and 30 other institutions have published the most comprehensive, accurate and high-resolution relief maps ever made of Greenland’s bedrock and coastal seafloor.
Among the many data sources incorporated into the new maps is data from NASA’s Ocean Melting Greenland campaign.

Lead author Mathieu Morlighem of UCI had demonstrated in an earlier study that data from OMG’s survey of the shape and depth, or bathymetry, of the seafloor in Greenland’s fjords improved scientists’ understanding of both the coastline and the inland bedrock beneath glaciers that flow into the ocean.
That’s because the bathymetry at a glacier’s front limits the possibilities for the shape of bedrock farther upstream.

(a) Data coverage, including ice-penetrating radar measurements (Center for Remote Sensing of Ice Sheets, High CApability Radar Sounder, University of Denmark, Uppsala University, Pathfinder Advanced Radar Ice Sounder, Alfred Wegener Institute) and ocean bathymetry (from single-beam data in dark blue),

and (b) BedMachine v3 bed topography sources, which include mass conservation (MC), kriging, Greenland Ice Mapping Project (GIMP) (Howat et al., 2014), RTopo-2/IBCAO v3 (Jakobsson et al., 2012; Schaffer et al., 2016), and bathymetry data from multibeam and gravity inversions acquired after the compilation of IBCAO v3.

The nearer to the shoreline, the more valuable the bathymetry data are for understanding on-shore topography, Morlighem said.
“What made OMG unique compared to other campaigns is that they got right into the fjords, as close as possible to the glacier fronts. That’s a big help for bedrock mapping,” he added.

Additionally, the OMG campaign surveyed large sections of the Greenland coast for the first time ever.
In fjords for which there are no data, it’s difficult to estimate how deep the glaciers extend below sea level.

(a) BedMachine v3 bed topography (m), color coded between −1500 m and +1500 m with respect to mean sea level, with areas below sea level in blue

and (b) regions below sea level (light pink) that are connected to the ocean and maintain a depth below 200 m (dark pink) and that are continuously deeper than 300 m below sea level (dark red).

The thin white line shows the current ice sheet extent.

The OMG data are only one of many datasets Morlighem and his team used in the ice sheet mapper, which is named BedMachine.
Another comprehensive source is NASA’s Operation IceBridge airborne surveys.
IceBridge measures the ice sheet thickness directly along a plane’s flight path.
This creates a set of long, narrow strips of data rather than a complete map of the ice sheet.

Savissuaq Gletscher area in the GeoGarage platform (DGA chart)

Besides NASA, almost 40 other international collaborators also contributed various types of survey data on different parts of Greenland.

No survey, not even OMG, covers every glacier on Greenland’s long, convoluted coastline.
To infer the bed topography in sparsely studied areas, BedMachine averages between existing data points using physical principles such as the conservation of mass.

Bed topography for different sectors of Greenland:

(a) the region of Savissuaq Gletscher, (b) Hayes Gletscher, (c) Illullip Sermia, (d) Mogens Heinesen N, (e) Heimdal Gletscher, and (f) Skinfaxe.

The yellow/red lines indicate the ice front position between 1985 and today from Landsat data, and the white dotted line shows the profile used in Figure 1.

The topography is color coded between −700 m and 800 m, and contours are shown every 200 m from −800 m to 200 m above sea level.

Some glaciers, such as the one 10 km northwest of Heimdal Gletscher, were not mapped using MC.

The new maps reveal that two to four times more oceanfront glaciers extend deeper than 600 feet (200 meters) below sea level than earlier maps showed.
That’s bad news, because the top 600 feet of water around Greenland comes from the Arctic and is relatively cold.
The water below it comes from farther south and is 6 to 8 eight degrees Fahrenheit (3 to 4 degrees Celsius) warmer than the water above.
Deeper-seated glaciers are exposed to this warmer water, which melts them more rapidly.

Surface and bed topography along six profiles (see white dotted lines in Figure 2) from this study (solid black) and bed from B2013 (dotted red, Bamber et al., 2013) and RTopo-2 (dotted yellow, Schaffer et al., 2016). Multibeam bathymetry data (MBES) are shown in blue.

The vertical lines show the ice front position between 1995 and today.

Morlighem’s team used the maps to refine their estimate of Greenland’s total volume of ice and its potential to add to global sea level rise if the ice were to melt completely, which is not expected to occur within the next few hundred years.
The new estimate is higher by 2.76 inches (7 centimeters) for a total of 24.34 feet (7.42 meters).

OMG principal investigator Josh Willis of JPL, who was not involved in producing the maps, said, “These results suggest that Greenland’s ice is more threatened by changing climate than we had anticipated.”

On Oct. 23, the five-year OMG campaign completed its second annual set of airborne surveys to measure for the first time the amount that warm water around the island is contributing to the loss of the Greenland ice sheet.
Besides the one-time bathymetry survey, OMG is collecting annual measurements of the changing height of the ice sheet and the ocean temperature and salinity in more than 200 fjord locations. Morlighem looks forward to improving BedMachine’s maps with data from the airborne surveys.

The maps and related research are in a paper titled “BedMachine v3: Complete bed topography and ocean bathymetry mapping of Greenland from multi-beam echo sounding combined with mass conservation” in Geophysical Research Letters.
This project received support from NASA’s Cryospheric Sciences Program and the National Science Foundation’s ARCSS program.

Links :

• GeoGarage blog : Greenland’s coasts are growing as seas rise / Global warming is melting the Greenland ice ... / Map provides high-resolution look at ... /

How 16th-century European mapmakers described the World’s oceans

A 13th-century depiction of the world as a circle divided by into three continents, Asia, Europe, and Africa.

British Library/ Public Domain

From Atlas Obscura by Genevieve Carlton

For some, they were an obstacle.
For others, they were an opportunity.

According to medieval mapmakers, the world was made up of three continents ringed by narrow bodies of water.
When the voyages of Christopher Columbus, Amerigo Vespucci, and Ferdinand Magellan uncovered continents previously unknown to Europeans, this posed a major problem for those cartographers.
But these explorers did not just stumble upon uncharted land—they also became aware of expansive stretches of ocean around the world.

 Bünting Clover Leaf Map.
A 1581 woodcut, Magdeburg.

Jerusalem is in the center, surrounded by Europe, Asia and Africa.

For the first time, Europeans were confronted with the realization that they lived on a blue planet, with 71 percent of the Earth’s surface covered by water.
The narrow strips of blue on medieval mappae mundi—also known as T-O maps, which showed the earth as a T centered on Jerusalem—were suddenly dwarfed by unimaginably vast oceans.
Stories about the European discovery of the New World are ubiquitous, but stories about the discovery of so much new water are much more rare.

 Map of Borneo by Pigafetta.

For explorers, these oceans were dangerous obstacles.
Attempting to traverse them could quickly turn deadly, as the sailors on Magellan’s expedition learned when only one of their five ships—and 18 of the original 280 crewmen—returned to Spain in 1522.
Antonio Pigafetta, one of Magellan’s surviving men, described this first Pacific Ocean crossing, which took three months and 20 days, in a report.
He wrote, “We only ate old biscuit reduced to powder, and full of grubs, and stinking from the dirt which the rats had made on it when eating the good biscuit, and we drank water that was yellow and stinking.”

 Claudius Ptolemy, 13th Century world map

The oceans also posed a problem for mapmakers.
Reports from explorers deviated wildly from pre-Columbian perceptions of the world’s water, as evidenced in mappae mundi.
The 1475 world map in Lucas Brandis’s Rudimentum novitiorum captures this older outlook on the world.
Asia, at the top of the map, represents one hemisphere, while wedges depicting Europe and Africa sit in the bottom half of the world.
The map was not intended to be representative; instead it focused on a Christian ordering of space with Jerusalem at the world’s center.
The world’s territories appear as hills, and in Europe, rulers sit atop them, with the pope in Rome shown holding a gold cross.
Asia and Africa, less well known to 15th-century Europeans, have more fanciful illustrations, including a pair of dragons, a burning phoenix, and a man-eating demon chasing his victim while clutching his severed arm.
On the map, the Mediterranean separates Europe from Africa and the rivers Don and Nile mark the divide between Asia and its neighbors.
Yet on this particular map, these bodies of water are marked by thin black lines and nothing more.
The only water seems to flow from the four great rivers at the top of the map, which represents the Garden of Eden’s Earthly Paradise.

A 1475 woodcut world map, published in Rudimentum novitiorum.

Public Domain 

The discovery of massive bodies of water forced mapmakers to devise creative solutions.
One of the earliest strategies was to shrink the oceans.
Here, mapmakers borrowed from Columbus himself, who minimized his trans-Atlantic voyage by claiming that the crossing took only 33 days.
However, Columbus only counted from the Canary Islands to the Indies, omitting the 37 days spent traveling from Spain to the Canaries, which included repairs on two of his three ships.

Cantino planisphere (1502)

One of the earliest maps to show the New World, the 1502 Cantino planisphere, shrunk the Atlantic by showing Flores Island, the westernmost of the Azores, just slightly west of the jutting coast of Brazil, when in fact it is several degrees of longitude east of the Brazilian coast.

 Battista Agnese world map (1544)

Battista Agnese, a Genoese mapmaker who produced at least 100 hand-drawn atlases for wealthy patrons, also narrowed the Atlantic in his 1544 world map.
Agnese drew only 10 degrees of longitude between Brazil’s furthest east point and Africa’s furthest west, nearly halving the actual distance of over 3,000 kilometers (1,864 miles).
These cartographic manipulations consistently under-measured the Atlantic, minimizing the distance between the Old World and the New.

From 1570, a world map by Abraham Ortelius. Public Domain

Sixteenth-century mapmakers also invented massive “undiscovered” continents to fill the oceans.
Two of the most famous maps from the 16th century, Abraham Ortelius’s 1570 world map in his atlas Theatrum Orbis Terrarum, and Gerhard Mercator’s 1569 world map, (which introduced the Mercator projection) rely on this approach.
Produced less than a hundred years after the Rudimentum novitiorum, Ortelius’s map shows a completely transformed globe.
The shapes of the world’s continents, recognizable to our contemporary eyes and now divided by the grid of latitude and longitude, are arranged with north at the top, a convention that only emerged in the 16th century.
The least familiar part of the globe is its southern stretches, which Ortelius labels “Terra Australis Nondum Cognita,” or southern land not yet known.

 1604 copy of 1602 Kunyu Wanguo Quantu

Both the Ortelius and Mercator map admitted that the world’s oceans were vastly larger than those shown on any pre-Columbian map, but both also hypothesized a massive southern continent to “balance” the landmasses north of the equator.
Mercator made this explicit in 1595, when he wrote, “it was necessary for such a continent to exist below to Antarctic Pole, which … would balance the other lands.” Europeans were so certain that this continent existed that Australia, first spotted by Europeans in 1606, took its name from the Latin term for Terra Australis.
These imagined continents did not just multiply the Earth’s land—they also limited the disturbing vastness of the world’s oceans.

 Gerard De Jode Universi Orbi seu Terreni Globi (1578)

Other cartographers embraced the ocean’s blank canvas in a different way: by emphasizing just how empty it was.
In addition to minimizing the size of the Atlantic in his beautifully-colored maps, Agnese painted the land a rich green, depicting the mountains, rivers, and lakes that dotted the territory.
On the land, water is drawn in brilliant blue, and the Red Sea and the Gulf of California are colored red, a convention borrowed from mappae mundi.
The ocean, by contrast, was largely blank, the untreated vellum standing in for water.
Agnese did scatter a few islands throughout and used the blank space to highlight Ferdinand Magellan’s route as he circumnavigated the globe.
But his map implies that Magellan did not discover anything notable in the ocean; rather, the ocean was an emptiness between “real” places, defined by the absence of land rather than containing anything worth recording.
Agnese’s unknown land, or terra incognita, which also faded into blank vellum, was visually identical to the explored oceans, perhaps hinting that the ocean was ultimately unknowable.

"A Complete Geographical Map of all the Kingdoms of the World" (坤輿萬國全圖),

the first Chinese world map, 1602

But the seeming blank space of the ocean signified more than peril and emptiness—it also posed an opportunity for enterprising mapmakers.
Blank spaces on the map could be filled with promotions for the map’s creator or his hometown.
The French royal cosmographer and mapmaker André Thévet manufactured not one but two fictional Thevet Islands in the Atlantic in the 1580s.
Similarly, in a 1558 book with an accompanying map, Nicolò Zeno, a Venetian nobleman from a flagging family, alleged that his familial predecessors, Nicolò (his namesake) and Antonio Zeno, had landed on the invented island of Frisland and led voyages in the North Atlantic that discovered the New World in 1380, over a century before Columbus’s Genoa or Vespucci’s Florence could claim the glory.
And on his 1560 world map, Paolo Forlani, one of Venice’s most active mapmakers, used the wide oceans to promote Venice by sprinkling the Atlantic, Pacific, and Indian Oceans with Venetian galleys, clearly not designed for transoceanic voyages.
The ships not only filled the water, but they also proclaimed Venetian dominance in an era when Venice had already lost the race to colonize distant territories.

Forlani’s map of North America from 1566. Public Domain

Mapmakers also explored a range of design techniques to fill the oceans.
Giovanni Lorenzo D’Anania’s 1582 map of the North Atlantic not only populated the waters with imaginary islands, but also filled the sea with dark dots and large labels for the land, minimizing the impression of blankness.
In his 1566 map of North America, Forlani similarly peppered the Atlantic with islands both real and invented, expanded the size of North America, and dotted the waters on his engraving to avoid the impression that the oceans were simply blank.
He also made the Pacific much smaller than the Atlantic, placing the island of Japan halfway between North America and Asia.

Map of the Southern hemisphere, 1593 by Gerard de Jode

These mapmakers and the explorers who crossed the newly found oceans saw the water both as an obstacle, separating Europeans from their destination and posing countless dangers, and as an opportunity.
A blank space on a map let a mapmaker reinvent himself, much like pirates who roamed the seas, by manufacturing islands or adding flourishes to promote his city.
And when mapmakers signed their works, they almost always did so in the ocean.

Links :

• GeoGarage blog : Ancient nautical maps' surprising accuracy ... / From Ptolemy to GPS, the brief history of maps / The greatest maps in history, collected in ... / Maps have ‘north’ at the top, but it could’ve ... /  Portolan charts 'too accurate' to be medieval / The golden age of nautical charts - When ... / The making of a mysterious Renaissance map / Venetian navigators : the voyages of the ... / The end of the map : why the World looks ...
• LOC : Portolan atlas of the Mediterranean Sea, western Europe, and the northwest coast of Africa
• Avan Stallar : maps gallery

Bird vs fish

Giant trevallies launch themselves out of the water to catch fledgling terns.

 

Links :

• The Conversation : Blue Planet academic consultants on the message that humanity cannot afford to ignore
• GeoGarage blog : David Attenborough on the scourge of the oceans: 'I remember being told plastic doesn't decay, it's wonderful'

Mystery of Kitfield Ledge solved with a little nautical chart research

Left: Current edition of NOAA chart 13279   /   Right: 1912 edition of chart 243.

From NOAA by Nick Perrugini

Most NOAA Office of Coast Survey customers have a practical mariner’s bent—they are interested in up-to-date and accurate navigational products and services.
However, an increasing number of customers are using Coast Survey online resources for historical research.

In May 2017, Coast Survey received an inquiry via the Inquiry and Discrepancy Management System (IDMS) that illustrates this point.
Original message: My dad is from Manchester-By-Sea, MA. There is a ledge on the NAUTICAL charts, “Kitfield Ledge”. Is there a place where we can get some history, when it was named, and how it came about. We have not been able to find any information on that. My dad was born in 1926, and he and his dad, used to lobster off of Black Beach in the 1930’s. We were back there 2 years ago and did some research at the Cape Ann Museum, but were not able to locate any information. Appreciate any help you may be able to provide. Thank you.

 Kitfield Ledge with the GeoGarage platform
& Google Maps search

 Kitfield Ledge with the GeoGarage ENC platform and Bing satellite imagery
(ENC with depths in meters)

The first step in solving this mystery was to locate Kitfield Ledge on the current chart.
Using the “Place Names” search in the Chart Catalog, Kitfield Ledge was located on the current edition of chart 13279.

Using the Historical Map & Chart Collection, I was able to trace the name back to Coast and Geodetic Survey Chart 243 published in 1912.

 An historic nautical chart of Ipswich Bay to Gloucester Harbor, Massachusetts published in 1912 by the U.S. Coast & Geodetic Survey showing topography, water depths in fathoms, and nautical features.

source : Amazon

Interesting….but where to go from here?
I then accessed the hydrographic surveys archive maintained by NOAA’s National Center for Environmental Information (NCEI, formerly NGDC).
Using the interactive map interface for bathymetric data, I was able to view and download an 1896 hydrographic survey that showed Kitfield Ledge.
Geographic name references are not always included in hydrographic survey descriptive reports, however to my surprise,the following note was discovered in the hand written descriptive report.

(Transcription)

45. “Kitfield’s Ledge.  This ledge lies SW of Crow Island with a least depth of 2 ½ fathoms.  It is covered with kelp and Crow Island Rock is situated on it. Its name was derived from the fact that at old woman, Granny Kitfield by name, used to fish for cod on it with much success.“

Granny Kitfield must have been quite an angler to have a rocky ledge named after her!
The Granny Kitfield inquiry, and its resolution, illustrates that Coast Survey (and other organizations within the National Ocean Service) offer impressive online resources to assist in historical research.
Many customers are interested in what shoreline or coastal features looked like a century ago.
Others are interested in where a currently charted feature (like a wreck) originated.
Resources that may help customers interested in historical research include:

• Historical Charts
• Hydrographic Surveys Archive
• Historical T-Sheets 
• Wrecks and Obstructions
• Historical information about charted features: Coast Survey’s Marine Chart Division’s Nautical Data Branch does a stellar job of tracking down the origin of currently charted features.

So go ahead, check these resources out.
Mysteries of the deep are waiting to be discovered—or maybe you’ll find another one of Granny Kitfield’s favorite fishing spots.

BP and Shell planning for catastrophic 5°C global warming despite publicly backing Paris climate agreement

Neither company sets targets to reduce emissions and
BP’s total investment in renewable and clean technologies has actually shrunk since 2005, 
the report said 

From The Independant by Ben Chapman

Companies are trying to 'have their oil and drink it' by committing to 2°C in public while planning for much higher temperature rises, says shareholder campaign group, ShareAction

Oil giants Shell and BP are planning for global temperatures to rise as much as 5°C by the middle of the century.
The level is more than double the upper limit committed to by most countries in the world under the Paris Climate Agreement, which both companies publicly support.

The discrepancy demonstrates that the companies are keeping shareholders in the dark about the risks posed to their businesses by climate change, according to two new reports published by investment campaign group Share Action.
Many climate scientists say that a temperature rise of 5°C would be catastrophic for the planet.

ShareAction claims that the companies’ actions put the value of millions of people's pensions at risk.
Two years after BP and Shell shareholders voted resoundingly in favour of forcing the companies to make detailed disclosures about climate risks, the companies have made unconvincing steps forward, according to the reports.
ShareAction said that Shell and BP are meeting their legal requirements, but are putting shareholders’ capital at risk because of numerous failings in their plans for the future.

Neither company sets targets to reduce emissions and BP’s total investment in renewable and clean technologies has actually shrunk since 2005, the reports said.
That’s despite the company’s public-facing image of being “beyond petroleum”.

BP invests just 1.3 per cent of its total capital expenditure in low-carbon projects while Shell has pledged to invest 3 per cent of its annual spend on low-carbon by 2020.

Both companies assess the resilience of their businesses against climate models in which temperatures warm by between 3°C and 5°C.
A maximum warming of 2°C beyond pre-industrial levels is the central aim of the landmark Paris climate agreement, which both firms say they support.
It is widely believed that any warming beyond 2°C could cause serious and potentially irreversible changes to the climate.
Shell reaffirmed its commitment to the Paris Agreement in a statement publicising its most recent AGM.
“Shell has a clear strategy, resilient in a 2°C world,” the company said, but its change modelling document states that “the emissions pathways until the middle of the century overshoots the trajectory of a 2°C goal”.

ShareAction’s report also found that top executives at both Shell and BP are still given incentives to pursue strategies centred on oil and gas and are paid bonuses over three to six years for fossil fuel projects that could have damaging effects for shareholders decades later.
Michael Chaitow, senior campaigns officer at ShareAction, said the report revealed an “uncomfortable discrepancy” between Shell and BP’s public support for a low-carbon economy and their actual business planning.
“Shell and BP want to have their oil and drink it too, by advocating for the landmark Paris Agreement to limit global temperature rises to below 2°C degrees, while planning for scenarios that would violate it,” he said.

The group called on Shell and BP shareholders, which include powerful institutional investors, to demand that the two oil companies do more to tackle climate change.

In 2015, more than 98 per cent of shareholders in both Shell and BP voted for resolutions that require the companies to regularly report on their emissions, resilience to climate change, investment in low-carbon technology and executive incentives.
The resolutions helped pave the way for subsequent shareholder resolutions on climate-related disclosure at oil and gas companies including Exxon and Occidental Petroleum.

Following the Shell and BP resolutions, billionaire businessman and former New York Mayor, Michael Bloomberg, founded a task force to press companies to properly disclose to the world the risks that climate change presents.

Catherine Howarth, chief executive of ShareAction, said the chief executives of both Shell and BP are running companies that look “poorly prepared for the speed of technological and economic change now underway in the global energy market”.
She added: “Millions of pension savers are exposed to Shell and BP’s shares. These reports challenge the professional investors looking after our pension savings to manage the growing financial risks facing BP and Shell more actively in the coming year.”

Neither BP nor Shell would comment on the report directly.
BP said it “anticipates a range of scenarios to give us flexibility in our approach".

Links :

• The Independant : Gas companies spend €104m lobbying to ensure Europe remains 'locked in' to fossil fuels for decades, report finds
• Desmog : Shell, BP Climate Disclosures 'Just a Marketing Tool' — Report
• LATimes :  What Exxon knew about the Earth's melting Arctic
• Investors : Royal Dutch Shell charges into a future beyond oil
• NYTimes : Saudi Arabia’s Grand plan to move beyond oil: Big goals, bigger hurdles 
• Wired : Could San Francisco get the oil industry to pay for Climate change ? 
• OilPrice : Big Oil Sinks $1 Billion into climate fund
• UN : Carbon dioxide levels surge to new high in 2016, UN weather agency reports 
• The Guardian : Global atmospheric CO2 levels hit record high
• GeoGarage blog : In a 1991 film, Shell Oil issued a stark warning about climate change risks, and much of it has proved to be true