Wednesday, February 25, 2026

Primar reaches milestone proposing more than 25,000 vector nautical charts in the ENC world catalogue


3 years later, a new milestone for Primar with an increase of 25% in the number of active ENCs
(from 20,000 to 25,041 ENCs today from 81 countries)
 
see ENC worldwide coverage with GeoGarage Google Earth plugin
All these charts can be used under conditions with the GeoGarage platform
in webmapping or GIS applications for third parties in B2B mode

IHO member states
 
Existing ENC but non RENC,
 so not provided by Primar
mainly produced by TH Thailand & GB with associated countries
(dual-badge ENCs, so blocked by UKHO for Primar)
 

New analysis hints ancient explorers mapped Antarctic

A map that shows Antarctica nearly 300 years before it was discovered ?
In 1531, French mathematician and cartographer Orontius Finaeus published a world map that included a detailed southern continent resembling Antarctica.
What makes the map so unusual is that Antarctica would not be officially discovered until more than 300 years later.
Even more striking, the landmass is shown with rivers, coastlines, and internal features beneath what is now miles of ice.Some researchers have suggested the map may have been copied from far older source material, possibly preserved through lost charts or ancient geographic knowledge passed down through time.
Others argue the continent was drawn theoretically, based on the long-held belief that a southern landmass must exist to balance the world.Whether advanced guesswork or inherited knowledge, the map raises an uncomfortable question.
How was a continent drawn in such detail long before anyone was supposed to have seen it?
 
 
From NYTimes by Walter Sullivan
 
FOR years a few imaginative authors have argued, based on 16th century maps, that the ice-covered continent of Antarctica was discovered and mapped by an ancient civilization, perhaps one from another planet.
The latter proposition was dismissed by most geographers and historians as preposterous.

Nevertheless, a careful comparison of information appearing on the maps with what is now known of the continent has led a leading geologist and polar specialist to propose that the outlines of Antarctica may, in fact, have been known long before Columbus reached America.

The generally accepted view is that Antarctica was first sighted in 1820 by American seal-hunters as well as by British and Russian explorers.

The suggestion that it may have been discovered many centuries earlier has been made by Dr. John W. Weihaupt, vice chancellor for academic affairs at the University of Colorado at Denver.
His analysis appears as the lead article in the Aug. 28 issue of Eos, the Proceedings of the American Geophysical Union.

Dr. Weihaupt, a specialist in seismic and gravity studies and planetary geology, conducted research at a number of Antarctic stations beginning with the International Geophysical Year of 1957- 58.

Interviewed by telephone recently, Dr. Weihaupt was reluctant to speculate on how the rough outline of Antarctica might have become known to early mapmakers, saying he was not a maritime historian.
He suggested, however, that Bronze Age seafarers from the Mediterranean, trading along the east and west coasts of Africa, might have ventured farther south than previously believed.
 


A Peaking Period of Warming

From 2,600 to 9,000 years ago, he said, the world was warmer than at any time in the last million years, except for the period between the last two ice ages.

Polar ice was presumably reduced, making high latitudes more tempting to explore.

Dr. Weihaupt says that, assuming the outline of Antarctica was known to early cartographers, the source of their information ''remains unanswered.''
Even crude mapping of a large continent would require a knowledge of navigation and geometry presumably beyond the ken of primitive navigators.

Speculation on prehistoric discovery of Antarctica began in 1956, when a map of the Atlantic Ocean purportedly drawn in 1513 by a Turkish admiral named Piri Re'is was shown by a Navy cartographer to Arlington H. Mallery, an engineer.
Mr. Mallery was known for his thesis that Vikings reached American shores five centuries before Columbus.

The map supposedly contained information from voyages made by Columbus.
It showed the western bulge of Africa with considerable accuracy and what seemed a crude outline of the opposite coasts of the Americas.
Those coasts continued unbroken around the southern extremity of the Atlantic, where Antarctica's Queen Maud Land is now known to lie.

This was taken by Mr. Mallery as evidence that the continent at the bottom of the world was already known.
American cartographers had seen the map as early as 1932, but little attention had been paid to its possible implications regarding Antarctica.

Mr. Mallery's argument was picked up by Prof. Charles H. Hapgood, a historian at Keene Teachers College in New Hampshire.
Professor Hapgood had published a controversial book arguing that off-center accumulations of polar ice sometimes caused gradual, but radical changes in the axis of the earth.

His analysis of the Piri Re'is map was published in 1966 under the title ''Maps of the Ancient Sea Kings - Evidence of Advanced Civilization in the Ice Age.''
He also cited several other early maps upon which Dr. Weihaupt now bases his argument.

They are the Orontius Finaeus world map of 1531, the Gerhardus Mercator world map of 1538 and a map of the Americas produced by Ptolomaeus Basilae in 1540.

Professor Hapgood proposed that the Orontius Finaeus map showed the coast of Antarctica as it would appear if the continent were not covered with ice, as may have been the case between the last two ice ages.

The suggestion that Antarctica had been mapped by some civilization that thenvanished won few adherents among historians and geographers.

Two years after the book appeared, however, Erich von D"aniken, a Swiss hotel-keeper turned writer, carried the argument one large step further. In his book ''Chariots of the Gods?'' he proposed that the maps were derived from aerial views obtained by visitors from beyond the earth.

Dr. Weihaupt said he ignored the Piri Re'is map as of questionable authenticity.
He concluded, however, that the Orontius Finaeus and Mercator maps, through their resemblance to the actual outline of Antarctica, ''suggest that man's knowledge of that continent may date from a time somewhat earlier than that century,'' or at least three centuries before the continent's modern discovery.
 

A Modern and Complete Map of the World by the Royal Mathematician Oronce Fine of the Dauphiné.
LOC 
 
Virtually Complete Outline

Both maps show virtually the complete outline and details of a continent that, like Antarctica, is centered on the South Pole.

Generations of scholars have debated over who discovered Antarctica.
The American candidate has been Nathaniel Palmer, captain of a sealing sloop from Stonington, Conn. American and British sealers had begun hunting south of Drake Passage below Cape Horn and on Nov. 17, 1820, Palmer sailed farther south and may have sighted the tip of the Antarctic Peninsula.

The British candidate is Edward Bransfield of the Royal Navy, ordered to explore the area for an outpost to control the south side of that critical waterway between the Atlantic and Pacific.Britain gives Jan. 30, 1820, as the date of Bransfield's discovery.

Two weeks earlier two Russian ships under Adm. Thaddeus von Bellingshausen may have sighted the ice-covered Princess Martha Coast.

Multinational exploration of Antarctica and probing of its ice cover have now produced relatively complete maps of the continent as it would appear free of ice.

Deep fiords would exist where ice streams now reach the sea. An archipelago comparable to the Philippines would lie south of Drake Passage.
The Ross Ice Shelf, an apron of ice 1,000 feet thick and as large as France, would be an open gulf.

The Orontius Finaeus map shows such a gulf, suggesting the possibility it was free of ice at some prehistoric time.
Dr. Weihaupt cites polar specialists who suspect the Ross Ice Shelf may break up into icebergs and vanish if the climate warms and he proposes this may already have happened after the last ice age.

Some ancient Greek philosophers suggested that, to make the world symmetrical, there should be a large land mass at the South Pole to balance the northern continents.
Maps such as that of Orontius Finaeus were explained as flights of imagination based on such reasoning.
But Dr. Weihaupt finds the resemblance to what is now known of the continent, in terms of its size, outline and scattered mountain ranges to be striking.

''The geography of the southern continent,'' he concluded, ''may thus have been known in its broad configuration before the mid-16th century. While the evidence bodes thus, I have no hesitation in reminding the reader, as myself, of Sir Walter Raleigh's admonition that conjectures 'painted on Maps, doe serve only to mislead such discoverers as rashly believe them.' ''
 
Links :

Tuesday, February 24, 2026

Maritime boundary dispute between Ghana and Togo: causes, history, conflict risk, consequences, and scenarios




From RLI Robert Lansing Intitute
 
Ghana has formally notified Togo that it will pursue international arbitration under the United Nations Convention on the Law of the Sea (UNCLOS) to resolve a longstanding dispute over their maritime boundary in the Gulf of Guinea.
 
This move reflects deep-rooted historical disagreements, competing economic interests linked to offshore oil and gas rights, and frustration with failed bilateral negotiations.
By choosing a legal pathway, Accra aims to reduce tensions while preserving peace, but underlying strategic interests still carry the risk of future conflict if the arbitration outcome is contested.


 
Historical Background and Causes of the Dispute

Colonial Legacy and Ambiguous Borders

Like many African maritime disputes, the Ghana–Togo conflict has roots in colonial-era frontier demarcations.
Boundaries drawn by colonial powers in the late 19th and early 20th centuries often lacked precise geographical coordinates, especially offshore.
This ambiguity became more consequential as offshore energy resources gained economic importance.
 
 visualization of Ghana-Togo nautical chart with EEZ in the GeoGarage platform (SHOM raster chart)
 
Ghana Togo EEZ (GeoGarage platform)
 
The dispute centers on how to delimit a maritime boundary that defines sovereign rights over offshore oil, gas, and potentially mineral deposits in the Gulf of Guinea.

Trigger Points

The most salient flashpoint occurred in 2017–2018, when Togolese authorities prevented Ghanaian seismic survey vessels from conducting oil and gas exploration in waters Accra considered its own.
Ghana viewed this as an infringement on its sovereign rights, while Togo asserted competing claims over the same maritime area.

Following the 2017 incident, the two countries formed a Joint Maritime Boundary Technical Committee tasked with developing a mutually acceptable delimitation.
However, persistent differences in methodological approaches, baseline coordinates, and nautical chart interpretations prevented agreement.
Efforts at joint patrols, fishing coordination, and non-invasive exploration were negotiated, but these interim measures did not resolve the core boundary question.

Strategic Stakes and Underlying Drivers

Economic Interests: Oil and Gas Prospects

The disputed area lies offshore in a region with significant hydrocarbon potential.
For Ghana, energy exports have been central to economic growth; securing maritime rights expands access to exploration and production.
For Togo, securing equivalent rights is crucial for diversifying its economy and capturing revenue from offshore energy.
These competing economic imperatives heighten the stakes of any boundary resolution.

Institutional Limitations

Both Ghana and Togo have strong incentives to maintain peaceful bilateral relations, but domestic political considerations complicate compromise.
National pride and political constituencies tied to oil sector expansion make territorial concessions politically sensitive.

Why Arbitration? Possibility of Escalation

Shift to Legal Resolution

By invoking international arbitration under UNCLOS, Ghana is signaling both frustration with bilateral talks and a preference for rules-based settlement.
This move may reduce immediate tensions by placing the dispute in a neutral legal forum rather than a political or military arena.

Risk of Non-Compliance or Contestation

Arbitration results under UNCLOS are legally binding; however, there is no supranational enforcement mechanismother than diplomatic and reputational pressures.
If Togo perceives the outcome as unfavorable, Accra’s reliance on legal authority may still be challenged politically—especially if resource revenues are at stake.

Low Likelihood of Military Escalation—But Not Zero

Historical patterns in the Gulf of Guinea show that maritime disputes between neighbors rarely escalate into armed conflict, largely because of regional institutions (like the African Union) and shared economic interests in cooperative security.
However, localized incidents—such as naval confrontations or fishing vessel detentions—remain possible if either side interprets enforcement actions as provocative.


Consequences of Arbitration and Possible Outcomes
  • Scenario A: Arbitration Decides in Ghana’s FavorClear boundary line defined according to UNCLOS principles.
Ghana gains exclusive rights to the contested offshore area.
Increased investor confidence leads to accelerated oil and gas development.
Togo may attempt to negotiate side agreements for revenue sharing or joint concessions to maintain stability.

-> Implications:
Economic benefits for Accra are substantial.
However, domestic political pressure in Lomé may rise if Togo perceives limited access to resources.
  • Scenario B: Arbitration Favors Togo or Splits the DifferenceThe decision might allocate portions of the contested area to both states.
Togo could claim validation of its sovereign claims.
Ghana may push for shared resource exploitation frameworks.

-> Implications:
This could ease bilateral tensions if framed as fair, but risk domestic backlash in Accra if perceived as a loss.
Cooperative frameworks for exploration and production could emerge.
  • Scenario C: Arbitration Decision Is Contested or RejectedTogo might question the legal basis or fairness of proceedings.
Bilateral tensions could rise again.
Threat of localized maritime incidents increases.

-> Implications:
Renewed diplomatic tensions could undermine regional cooperation and investor confidence.
Third-party mediation by the African Union or United Nations may be required.

Broader Regional Context

African states increasingly face maritime boundary and resource disputes across the continent, particularly in the oil- and gas-rich Gulf of Guinea.
Regional institutions such as the Economic Community of West African States (ECOWAS) and the African Union (AU) have frameworks for peaceful dispute resolution, but practical implementation varies by case.

 
In september 2017, Ghana wins its maritime boundary case n°23 against Cote d’Ivoire when the Special Chamber (SC) of the International Tribunal for Law of the Sea (ITLOS) delivered its judgment
source : Foley Hoag 

Policy Implications and Recommendations
  • Strengthen UNCLOS Implementation: Encourage both states to commit in advance to abiding by arbitration results.
  • Establish Joint Resource Management Zones: Even if boundaries are agreed, mechanisms for shared exploitation can reduce competition and enhance cooperation.
  • Regional Mediation Support: AU and ECOWAS should offer facilitation services to ensure arbitration does not reignite tensions.
  • Transparency Measures: Regular public communication on proceedings can manage domestic expectations and reduce nationalist rhetoric.
The maritime dispute between Ghana and Togo reflects historic boundary ambiguities, economic competition for offshore resources, and frustrated bilateral diplomacy.
Ghana’s decision to seek international arbitration under UNCLOS is a strategic attempt to resolve the dispute within a rules-based framework, lowering the risk of escalation.
While military conflict remains unlikely, diplomatic, economic, and political tensions persist, and outcomes depend heavily on the arbitration ruling and its acceptance by both parties.
The situation underscores broader challenges in African maritime boundary governance and the need for robust regional mechanisms for peaceful dispute resolution.

Links :

Monday, February 23, 2026

Changes in ice volume : Cryosat maps ice volume loss in Antarctica and the Arctic


This animation shows changes in ice volume in Antarctica, Greenland and the Arctic ocean measured by the CryoSat satellite, 2010–15.
CryoSat’s readings also contribute to our knowledge of global ocean depth.

From BBC by Jonathan Amos 

European scientists have found a way to super-charge their study of the ice sheets in Antarctica and Greenland.

The novel technique boosts the data about height changes that are gathered by radar instruments on satellites.
Known as swath altimetry, it permits researchers to see broader regions of the ice sheets in any one pass overhead, and at a much finer scale.
Areas of melting or accumulation can now be investigated with 100 times more information.
The new approach has so far been applied only to a small set of data acquired by the Cryosat spacecraft.
But the intention eventually is to go back and reprocess the entire six-year archive of observations made by this European Space Agency (Esa) mission.
Swath altimetry will totally change the way scientists are able to study some phenomena, says Dr Noel Gourmelen from Edinburgh University, UK.
"The temporal and spatial improvements mean that if we have a surge in a glacier, it now makes it much easier to look at where that event initiated. Did the whole glacier start moving at once?
Or did the change start at the ocean, meaning the ocean was having an impact on the glacier?
Or perhaps it was further back, meaning different processes were involved.
Now, we're better able to trace the history and the causes of the surge," he told BBC News.
To be clear, swath altimetry changes nothing about how Cryosat operates - only in the way its data is processed.
The spacecraft already has a special radar designed to meet the peculiar challenges of observing ice sheets.
With its twin antennas, the instrument can work in an interferometric mode, detecting not just the distance to a spot below it on the ice but also the angle to that location.
Without this ability, it would struggle to map effectively the steep slopes and ridges found at the edges of the ice sheets - the very locations where recent melting and thinning have been most pronounced.

 Cryosat has just super-charged its ability to map the ice sheets

Broader brush

But even in this improved mode, standard data processing concentrates on the nearest radar echo return point and ignores much of the energy in the rest of the signal.
Swath processing, on the other hand, unpacks it all, revealing a line of additional elevation points.
It is now possible to see more of the shape of a depression or valley, not simply the rim or ridge that surrounds it. And because the "brush" of detection is much broader, it takes less time to "paint" the map of an ice sheet.
"We can now see detail that was simply not possible before," said Cryosat's principal scientific advisor, Prof Andy Shepherd.
"We can now map with about 500m spatial resolution the elevation and elevation change of Antarctica and Greenland, and other ice caps and glaciers across the globe."

The power of swath altimetry

The images below of the Petermann Glacier in northwest Greenland show the effect of standard processing versus the new swath approach. The latter pulls out far more elevation information from the radar signal.



The new swath mode has been a major talking point here in Prague at the European Space Agency's Living Planet Symposium, as has the the future of Cryosat itself.
Its radar measurements are highly valued, and are credited with having transformed studies of the Arctic, the Antarctic and Greenland.
But the mission is now operating beyond its design lifetime and could die in orbit at any time.
Researchers have urged Esa and the European Commission to find the means to fund a follow on.
Dr Andrew Fleming from the British Antarctic Survey said if its strand of information was lost with no suitable replacement, it would send many researchers "to bed in tears".
Outgoing Esa Earth observation director, Prof Volker Liebig, said there was no plan for a direct successor, and there was insufficient time to build one even if the money was available.
But the idea that the commission could launch a similar satellite in its Sentinel series of spacecraft in the 2020s was now being discussed, he added.
Prof Liebig said there was no denying the importance of a Cryosat capability, particularly in studying Arctic sea-ice.
"[Cryosat] is a mission that has a geopolitical meaning because the Arctic is the place that will change most in our lifetime as a result of climate change," he told the symposium.
"Plus two degrees [in temperature increase] worldwide means plus six degrees or even 10 degrees at the poles. I've even seen some statements of plus 15 degrees. And this means that by mid-century, in only 30 years from now, Arctic sea-ice will have disappeared completely in summertime."

Sunday, February 22, 2026

Project Deep Blue

 
Project Deep Blue explores the hidden world beneath the ocean’s surface.
From shallow reefs to the deepest parts of the sea, we uncover marine life, underwater landscapes, and the mysteries of the deep ocean.
This channel features – Deep-sea exploration – Rare and unknown marine creatures – Underwater environments and geology – Ocean science and unexplained phenomena
Our goal is to educate, inspire, and spark curiosity about the vast blue world that covers most of our planet. 
 
Links :