Thursday, November 26, 2020

Atlantis isn’t real, but here are all the places it could have been

This map shows some of the places people have thought Atlantis might be hiding.
Craig Taylor
 
From Popular Science by Eleanor Cummins
 
Plato first described the lost kingdom of Atlantis in 360 BCE.
He wrote of a mountainous island crafted by Poseidon, filled with elephants and gold.
But around 9,000 years prior, he claimed, earthquakes and floods sank the city into the sea.

He probably made the whole thing up.
Still, that hasn’t stopped Atlantologists from gathering “evidence” of its existence.
Inspiration abounds: Coastal towns collapse and islands submerge, whether from rising oceans or sinking shorelines.
These lost lands offer a setting for theories on where the city may once have stood.
 
1932 map of lodt continent of Atlantis

1. Bimini Road

In the mid-'60s, divers encountered a remarkably straight half mile of evenly spaced, uniform stones.
Carbon dating and a lack of tool marks suggest natural erosion is responsible, but some believe it’s from a sunken civilization.

2. Souss-Massa Plain

A 2008 analysis of 51 Platonic descriptors of Atlantis identified several possible coordinates, including these coastal dunes, which feature intriguing concentric dry riverbeds.
Unfortunately, there’s scant evidence of any empire.

3. Spartel Bank

Plato said the lost city lay beyond the Pillars of Hercules—two rocks in the Strait of Gibraltar.
The island of Spartel once sat there.
Passing sailors may have seen it vanish at the end of the last ice age, but if so, they left no records.

4. Doggerland

The British Isles were once connected to Europe by a low-lying landmass.
But when a megatsunami struck around 6000 BCE, the region disappeared, leaving bones and tools from local hunter-gatherers embedded in the seafloor.

5. Helike


A tsunami walloped this Greek town in Plato’s day, and many assumed its remains lay in the Corinthian Gulf.
But in the 1990s, archaeologists found it half a mile inland, buried under a few dozen feet of sediment by a process called soil liquefaction.

6. Antarctica


Historian Charles Hapgood argued the southern continent was once a northern landmass with Atlantis on its shore.
Then, 12,000 years ago, a shift in the crust sent it south.
Antarctica did make that trip—some 30 million years ago.

7. Marshall Islands


We may have another “Atlantis” someday.
Sea level rise threatens coastal communities, including this network of atolls with an average elevation of just six feet.
Without intervention, they’ll likely be underwater by midcentury.
 

Conjectural map of Atlantis. 
 
Links :

Wednesday, November 25, 2020

Hydrospatial and the marine environment

A Hydrospatial Information System for multidimensional data.
Science Sisters – Oceanography and Hydrography
 
From Hydro by Rafael Ponce 

The First Steps to Going Beyond Charting

Hydrographic offices (HOs) today exist in a world of accelerating technological change that is influencing human behaviour and creating new needs and ways of exploiting data to understand our world.
HOs have traditionally been the producers of nautical information for safety of navigation.
By the end of the 20th century, with the appearance of the IHO S-57 Standard, their main challenge was to evolve into a central database production system.
Now, the critical challenge and opportunity is to evolve from there into a true geospatial agency, developing a hydrospatial information system (HIS) capable of providing products and services for multidimensional analysis and evidence-based decision-making, to support the growing Blue Economy and the United Nations (UN) Sustainable Development Goals (SDGs), through apps and web browsers at the "speed of trust."
The technology to do this is here today; it is a matter of vision and desire to propel HOs and their customers toward the next frontier.

Hydrography is defined in the International Hydrographic Organization (IHO) S-32 Hydrographic Dictionary (IHO, 2019a) as: "The branch of applied sciences which deals with the measurement and description of the physical features of oceans, seas, coastal areas, lakes and rivers, as well as with the prediction of their change over time, for the primary purpose of safety of navigation and in support of all other marine activities, including economic development, security and defence, scientific research, and environmental protection."

Perhaps the most important data asset that a HO possesses is bathymetry.
Bathymetry takes a lot of effort and dedication to collect – in the past with mechanical methods such as rods and lead lines, and today with sound, laser and imagery.
The final result is a number consisting of a measurement at a specific location and time.
Underwater Acoustic Signals

While there used to be just a few of these numbers, due to the effort that they took to collect, with today’s automation there can be billions of measurements.
Regardless of how many depths are collected, their main purpose is to populate a navigational chart, and collecting bathymetry for chart production is considered the traditional use of the data.
However, these same sound signals, or pings, are used for the sea-floor characterization of sub-bottom sediment layers, with sonars used as sediment profilers, often called sub-bottom profilers (SBP).
Using frequencies ranging from 1 to 10kHz, hydrographers can map the seabed and sub-bottom layers from sonar reflections, and obtain a better understanding of the sea floor’s physical properties.
The echoes are displayed graphically on the screen by reconstituting a vertical cross-section of sediment layers.
Using echo amplitude processing techniques and calibrated Sound Bottom Profiles, it is possible to retrieve the reflection and absorption coefficients associated with sediment layers crossed by the signal and to use these to classify the layers and identify sub-bottom areas of interest.
This is particularly relevant in providing additional uses and benefits, including contributing to the establishment of a country’s extended continental shelf, resulting in billions of dollars in economic value.

Chart Production and Location Intelligence

In the late 1990s and early 2000s, the challenge for HOs was to build central database systems from which paper/raster and Electronic Navigational Charts (ENC) and other information products could be created simultaneously.
Some HOs have achieved this; others are in the process of doing so.
In general, nearly all HOs, just like their land-based National Mapping and Geospatial Authority equivalents, understand the advantages of having a central database for the production of a multitude of information products, and the technology to build an enterprise production system is readily available through Geographic Information Systems (GIS).
Of course, we acknowledge the challenge of migrating to a new S-101 production system, but it is moving in slow motion compared to the marine world needs of today, and automation will support a smooth transition when migration to S-101 happens.
Now that we are entering the third decade of the 21st century, the challenge is to evolve the existing chart production system into a location intelligence system.
This will be enabled as production continues to transform through automation and we can focus our resources on expanding the use of hydrographic and oceanographic data in response to new demands from the marine world.
This expansion requires building a spatial data infrastructure (SDI), based on good governance, technology and people, to address these new demands – in this case, a Marine Spatial Data Infrastructure (MSDI).
Like other SDIs, it should utilize the best practices laid out in the UN Global Geospatial Information Management (UN-GGM) Integrated Geospatial Information Framework (IGIF).
An MSDI based on the IGIF will serve as the framework to develop a HIS and distribute new products and services, and to make existing ones available for a much larger user group, significantly raising the level of importance of HOs.
Such an infrastructure also increasingly needs to disseminate results as fast as possible, given the bandwidth of information transfer.
Where this once meant carrying paper surveys from the ship by hand, it is now only limited by the bandwidth of satellite throughput and web-based dissemination (which is rapidly improving through market innovation driven by applications).
This allows for collaboration in real time and helps increase the speed of trust by bringing the experts to the ship virtually, rather than waiting for the next voyage or year.

We can say that oceanography is indispensable for hydrography to be successful.
Physical oceanography parameters (such as pressure, temperature and density) combined with chemical parameters (such as salinity) are used to determine sound velocity profiles which, together with tidal data, help to determine bathymetric measurements.
These datasets, which are already collected by HOs, are very important for other applications and studies.
Biological factors also affect the sound profile, and understanding its variability with tide and wind action often leads to more questions than answers.
These issues are fundamental to what we might now call ocean weather (Hughes Clarke, 2017), and they contribute to the creation of an oceanographic information system (OIS).
This OIS is also part of the HIS and the next step of a HO toward achieving a digital transformation.
This oceanographic information is part of the location intelligence used in the HIS to identify, understand and predict the occurrence of phenomena, and in turn it too can be shared to the broader marine communities of use.

Multidimensional Marine Data Analysis

Bathymetry, sediment types, tides, currents, water mass physical characteristics and more can be used for marine data analysis.
HOs, through a HIS, play an increasingly important role in this.
Evidence of that relevance can be found in a recent study that shows how the rise in ocean temperatures is affecting sea grass, which together with mangroves and salt marshes stores up to 100 times more carbon than tropical forests, and at 12 times the speed (Aydin, 2017).
In identifying these environmental conditions, sea surface and water column temperatures, along with depth measurements and their trends and other oceanographic parameters, are very important.
For more information, please view the Transforming an MSDI into a Modern Hydrospatial Infrastructure webinar.

The use of bathymetry is fundamental for determining depth zonation for the classification of different types of ecosystems.
Marine mapping using echo-sounding technology detects not only the seabed morphology but also the presence of fauna and other materials in the water column, as mentioned above (volume backscattering).
Based on the deep scattering layer (DSL) and higher-density sound-scattering layer (SSL), scientists can detect animals moving vertically at different times of the day for feeding and protection.
These acoustic signals help to define the epipelagic and mesopelagic depth zones that can be correlated to climate change phenomena and, with the use of GIS models and algorithms in an MSDI, can predict biomass accumulation due to temperature-driven metabolism, growth, and trophic efficiency in the food chain (Costello and Breyer, 2017).
In classifying different pelagic regions, depth for stratifying the ocean is the first required parameter, which is valuable and more difficult to assess accurately as we go deeper and farther away from the coast.
Temperature and salinity measurements (parameters that, depending on the instrument type, are sometimes collected during hydrographic surveys) are also required.
 
 
A decision tree, created using ArcGIS Pro, for classification of sea grass.

A statistically-based classification of seabed habitats can be influenced by data contained in a HIS, such as bathymetry, slope, sediment thickness and geomorphology.
Surface primary production, bottom temperature and oxygen level complement the HIS data to identify different seascape types and then define a Marine Protected Area (MPA) network that can be used to analyse environmental variability in the water column and to compare the surface and the seabed.
This analysis allows scientists to classify blocks of ocean water mass as Ecological Marine Units (EMU) and to identify pelagic zones around the world.
EMUs provide a 3D framework up to a depth of 5,500 metres to stratify ocean sampling (Costello et al., 2018), where bathymetry is the geospatial foundation on which everything else is plotted.

These EMUs can be built at any area coverage level, from the worldwide network through the public-private partnership led by the US Geological Survey (USGS) and Esri, using the National Oceanic and Atmospheric Administration’s (NOAA’s) oceanographic data and commissioned by the Group on Earth Observations (GEO), to regional and local networks that can be built through an MSDI.
Combined with the fundamental contribution from a HIS of HOs in partnership with other agencies, these organizations support the wise use of the ocean for development and environmental resilience.
For example, to improve the regional ocean observation within the Marine Biodiversity Observation Network (MBON) (Esri, 2018), the determining seascapes project is funded under a National Aeronautics and Space Administration (NASA) Research Opportunities in Earth and Space Science (ROSES-16) A.50 GEO Work Programme.
This will evaluate dynamic seascapes on a global scale with a case study that focuses on the Arctic.
It includes comparisons of boundaries of surface seascapes with surface EMUs, particularly on seasonal scales, and comparisons of species distributions across classification schemes.
This joint effort will also facilitate the delineation of a useful MBON framework from pole to pole (Wright et al., 2018).

All of these examples highlight the relevance that a HIS, as a component of an MSDI, has in multidimensional marine data analysis and in the creation of new products and services that can be used for a wide variety of applications, involving the monitoring and evolution of our planet, from micro to macro levels and from environmental protection to economic and social development.

The Blue Economy

The World Bank defines the blue economy (World Bank, 2019) as the “sustainable use of ocean resources for economic growth, improved livelihoods and jobs while preserving the health of ocean ecosystem.”

The blue economy concept suggests that better stewardship of ocean resources that allows for sustainable development while managing the exploitation of marine and maritime resources – such as offshore energy, shipping, commercial fishing and mining – will ensure sustainable ocean health and a productive national economy.

The following are some important blue economy facts (The Commonwealth, 2019):
  • the total global ocean economy is valued at around US$1.5 trillion per year;
  • 80% of global trade by volume is carried by sea;
  • fisheries provide 350 million jobs worldwide;
  • aquaculture provides 50% of fish for human consumption and is the fastest-growing food sector;
  • by 2025, it is estimated that 34% of crude oil production will come from offshore drilling.

Shipping is a fundamental activity that contributes to the blue economy.
However, several measures have to be taken to make it safe, efficient and sustainable, from greenhouse gas (GHG) emissions control to the International Convention for the Prevention of Pollution from Ships (MARPOL) discharge regulations, and from the International Maritime Organization (IMO) International Convention for the Safety of Life at Sea (SOLAS) to e-navigation and port operations.
The shipping industry and naval forces are the main customers of HOs, consuming ENCs, paper and raster charts, and foundational maritime information for Artificial Intelligence (AI) such as finding obstructions to navigation (e.g. shipwrecks).
It is clear that there is no question about the contribution of hydrography to the blue economy.

Up-to-date charts distributed in a timely manner reduce the risk of accidents at sea and improve efficiency with better navigational routes.
These products are also used ashore, where monitoring ship traffic and port operations is important not only for safety and efficiency but also for regulating shipping emissions by including Automatic Identification System (AIS) data (location and speed) in a GIS, with parameters such as engine power and fuel consumption rates to estimate emissions in time and space.
This has been an important application in the Green Ports movement.

A HIS would provide the necessary resources to efficiently plan for navigation routes, ship speeds, bilge water management and port services.
 
 
Ecological marine units 3D visualization.
Maritime Boundaries Delimitation


One area that has always been critical for a maritime nation’s development is the realization of its maritime limits and boundaries, which will be defined in the new IHO S-121 Maritime Limits and Boundaries product specification.
Based on the UN Convention on the Law of the Sea (UNCLOS), these maritime limits define what level of jurisdiction and what resources a maritime nation has rights to beyond the shoreline.
Part of the responsibility of determining these limits lies with the national HO, which intervenes in delimiting the baselines.
These baselines determine the establishment of the territorial sea, contiguous zone and exclusive economic zone.
This information, along with the foot of the continental slope derived from bathymetric analysis, is combined with other criteria to determine the extended continental shelf zone.
The proper and accurate justification for claiming these areas is backed up by hydrographic, oceanographic, geological and geodetic data, which therefore has a very significant effect on a nation’s economy, usually measured in billions of dollars, and environmental well-being.
Nautical charts are the legal documents that describe the above-mentioned maritime boundaries.
These lines are used by mariners to know where they are and what legal jurisdiction they are sailing in and thus what activities are allowed within those waters.
The law enforcement agencies also use this geospatial information to ensure that the regulations are not violated and for resource surveillance in the water column, seabed and subsoil.

UN Sustainable Development Goals

At a global scale, nothing is more relevant than the UN Sustainable Development Goals (SDGs), an ambitious call for action to help countries achieve 17 social and economic development objectives by the year 2030.

Location information plays a very important role in measuring and making progress on the SDGs.
This is particularly true in the maritime community to achieve SDG-14, Life below Water.
Hydrographic information (bathymetry) is also the foundation of the ‘Elevation and Depth’ theme.
Comprehensive and authoritative bathymetric data complemented by geological and soils datasets from the seabed in a HIS are essential features to be provided by national HOs.
The nautical chart is also fundamental in the ‘Transport Networks’ theme, to identify marine and inland waterways that impact SDGs 2 (Zero Hunger), 3 (Good Health and Well-Being), 8 (Decent Work and Economic Growth), 9 (Industry, Innovation and Infrastructure) and 11 (Sustainable Cities and Communities) (UN, 2019a).

While a HIS can provide new products and services to support SDG-14, traditional products such as nautical charts have a very significant (and sometimes overlooked) impact on several other SDGs.
An important effort is being made by the UN Statistics Division and the UN-GGIM members to maintain an Open SDG Data Hub, which contains over one million observations.
An SDG indicators API has been created to give programmatic access to the global indicators database using the OpenAPI specification and thus to enable live information services to be provided.
 
 
Collecting bathymetric data using multibeam echosounders (MBES).
(Courtesy: iSURVEY Group)

Hydrospatial Information System

The UN Economic and Social Commission for Asia and the Pacific (ESCAP) has created a gateway to data portals, enabling people to access and download statistical information and filter it by specific SDG (ESCAP, 2019).
From here, the Resource Watch, which provides hundreds of datasets on the state of the planet and human well-being, can be accessed (ResourceWatch, 2019).

Filtering the data by the world oceans will render dozens of layers containing relevant hydrographic, oceanographic, biological, shipping and other information that users can combine for their own analysis.
This is an example of how a HIS can support this important global endeavour.

A HIS organizes hydrographic, oceanographic and other maritime data to focus on the business value of three main areas: marine environment, the blue economy, and maritime safety and security.

Recognizing that demand for hydrographic data is growing, and developing the technology to address those demands are the first steps to going beyond charting.
A clear vision will be required to establish the strategy for determining the destination of the HOs and the route to successfully reach the next geospatial frontier using HIS.

Tuesday, November 24, 2020

Stormy waters: Israel and Lebanon negotiate their maritime border

An Israeli military observation tower overlooking the Mediterranean Sea and part of the maritime border with Lebanon, is seen near Rosh Hanikra, in northern Israel October 13, 2020.
Reuters/Ammar Awad
 
From Atlantic Council by Udi Evental

After a decade of United States-led mediation, on October 14, delegations on behalf of Israel and Lebanon entered negotiations on the demarcation of their disputed maritime borderline.
These landmark talks were made possible following a framework agreement, of which details remain classified.

Two of the most significant obstacles on the long path leading to the negotiations were mediation and Beirut’s demand to couple together maritime and land border disputes.

Israel demanded that the US mediate while Lebanon was insistent that the United Nations (UN) lead the effort.
The dispute appears settled thanks to a formula that would place the talks under US mediation and UN sponsorship, therefore providing the UN with a meaningful role to play in the process.
 
Israel-Labanon frontier with the GeoGarage platform (SHOM nautical chart)

The disputed borders

As far as the land border is concerned, it seems that the agreement was worded with constructive ambiguity, expressing hope for future progress on this issue.
The US Assistant Secretary of State David Schenker, who led the mediation efforts, encouraged both sides to renew the dialogue to solve the disputed points in separate track talks between the Lebanese Armed Forces (LAF), Israel Defense Forces (IDF), and UN Interim Force in Lebanon (UNIFIL).
Such discussions take place every couple of months as part of a trilateral mechanism established after the 2006 Lebanon War.

As it stands, there are thirteen disputed points between Israel and Lebanon along the international land border known as the “Blue Line,” which was mapped out by the UN—and to which Israel withdrew in 2000.
Most of these disputes are a result of scale problems originating in the 1949 Armistice Agreement map, upon which the UN-demarcated Blue Line was based.

While the Blue Line continues eastwards to the Golan Heights, Lebanese militant group Hezbollah claims that the area of Sheba’a Farms, located on the western slopes of Mount Hermon, is conquered Lebanese land.
This view runs contrary to the stance of the UN and Israel, who regard the area as territory that once belonged to Syria.

The land border dispute is somewhat connected to the maritime border dispute.
Regarding the latter, much of Israel and Lebanon’s focus is on two points between which the demarcation line is drawn: a land-based point of origin at Rosh Hanikra and the western most point out at sea (two hundred nautical miles from the coast).
Israel has delineated a line extending northwards while Lebanon’s line inclines southwards.
The result is a triangular-shaped disputed area covering some 860 km2, estimated to be rich in natural gas fields and oil reserves.
 
A line of buoys placed by Israel near the Lebanese-Israeli maritime border, which is not recognized by Lebanon and the UN, seen from the southern coastal town of Naqoura, Lebanon, July 23, 2010.
(AP Photo/Mohammed Zaatari)
 
Pushback in Lebanon

As opposed to Israel, kick-starting negotiations in October resonated strongly and caused a political storm in Lebanon.
On the one hand, some commentators applauded the framework agreement, regarding it as a practical expression of the recognition of Israel and expressing hope that it would be completed for the good of the Lebanese national interest.

On the other hand, proclamations made by Hezbollah’s leader, Hassan Nasrallah, and pro-Hezbollah news outlets, such asAl-Akhbar and Al-Mayadeen, were more noticeable.
They expressed stark opposition to any symbolic gestures that could imply normalization.
Similarly,Ibrahim Alamin, editor of the Al-Akhbar newspaper—which is closely associated with Hezbollah—claimed that consenting to conduct negotiations with Israel reflects unprecedented Lebanese weakness, which is liable to invite US pressure to differentiate the demarcation of the maritime and land borders once and for all.

Interestingly, against a background of calls in the Lebanese media to adopt tougher positions, the Lebanese delegation placed a demand at the table that almost doubled the disputed 860 km2 area that had been negotiated in the past decade.
Fearing the move might derail the talks, the US and UN sought to pressure Lebanese President Michel Aoun into returning to the original framework of negotiations.

The Hezbollah factor

The talks between Israel and Lebanon over the maritime border demonstrate that Hezbollah no longer vetoes such negotiations after preventing any breakthrough in the last decade.

As far as Hezbollah is concerned, negotiations that make a distinction between the maritime and land borders—including the question of Sheba’a Farms—weaken its image as the “defender of Lebanon” and undermine its already-eroded legitimacy to possess “the weapon of the resistance” outside state control.
Moreover, the US—Hezbollah’s arch enemy and that of its patron Iran—is the key mediator in the talks.

Hezbollah was forced to swallow these bitter pills due to the special circumstances in Lebanon, first and foremost, its economic collapse.
Hezbollah’s opposition to negotiations that would potentially funnel billions of dollars to Lebanon would have reinforced public allegations that the organization disrupts the country’s ability to rise out of the crisis.
This is especially so given its support of the corrupt sectarian system and its efforts to stonewall the French initiative to set up a reformative government in Beirut, which would pave the way towards international aid.

Hezbollah’s need to compromise reflects the damage to its internal status within Lebanon and a degree of erosion in its overall deterrent capability vis-à-vis Israel.
The latter is why it has been so determined to avenge the death of one of its operatives in Syria in July and to continue its efforts to carry out an attack against Israel along the border.

Despite the concession it has made, Hezbollah is working to restrict the Lebanese negotiation team.
The idea is to gain a position of influence and to guarantee some portion of its dividends if Hezbollah fails in derailing the negotiations and the two countries eventually reach an agreement.

The big picture

It appears that most of the parties involved in the talks have an interest in their success.
Lebanon, much more than Israel, needs to resolve the dispute, as foreign companies currently hesitate to realize franchises or investments for exploration and drilling in the disputed area.
The extraction of the natural resources in the maritime border area will help Lebanon contend with the unprecedented crisis into which it has been plunged.
By doing so, it can limit its energy costs when faced with a collapsing electricity infrastructure, deal with the problem of air and environmental pollution, reduce its foreign debt—one of the highest in the world—and create jobs.

Israel’s potential profit could be mainly on a strategic level.
The negotiations—let alone an agreement—should reinforce stability with Lebanon and make it more difficult for Hezbollah to escalate the situation on the border.

The launching of talks is an important achievement for Washington, too.
The US has proven that it is still a significant player not only in the Gulf, but also in the Mediterranean, after its influence in Syria, Libya, and amongst the Palestinians has suffered setbacks in recent years.

Given these conditions, there is a chance that the negotiations could eventually make progress, even if they are expected to be long and arduous and, under certain circumstances, might become a hostage of the political instability in Lebanon.

In light of the extreme sensitivity attached to this issue in Lebanon, Israel must ensure that it conducts low-key negotiations.

Senior Israeli officials would do well to avoid making declarations regarding normalization with Lebanon or dwelling on the potential of any future Israeli-Lebanese cooperation, even if this entails profits for both sides (the conveyance of gas to Europe being an example).
It is also in Israel’s interest to maintain the trilateral track (IDF, LAF, and, UNIFIL) in parallel to the ongoing negotiations, and to try and use this framework to promote a solution to the disputed points along the Blue Line.

Links :

Monday, November 23, 2020

Which countries are mapping the ocean floor?


Spilhaus projection used by NZ cartographer Andrew Douglas-Clifford.

From Visual Capitalist by Nick Routley

Our vast and complex planet is becoming less mysterious with each passing day.

Consider the following:
Thousands of satellites are now observing every facet of our planet
Around three-quarters of Earth’s land surface is now influenced by human activity
Aircraft-based LIDAR mapping is creating new models of the physical world in staggering detail

But, despite all of these impressive advances, our collective knowledge of the ocean floor still has some surprising blind spots.

Today’s unique map from cartographer Andrew Douglas-Clifford (aka The Map Kiwi) focuses on ocean territory instead of land, highlighting the vast areas of the ocean floor that remain unmapped.

Which countries are exploring their offshore territory, and how much of the ocean floor still remains a mystery to us?
Let’s dive in.
 
What Do We Know Right Now?

Today, we have a surprisingly incomplete picture of what lies beneath the waves.
In fact, if you were to fly from Los Angeles to Sydney, the bulk of your journey would take place over territory that is mapped in only the broadest sense.

Most of what we know about the ocean floor’s topography was pieced together from gravity data gathered by satellites.
While useful as a starting point, the resulting spatial resolution is about two square miles (5km).
By comparison, topographic maps of Mars and Venus have a resolution that’s 50x more detailed.

As the map above clearly illustrates, only a few large pieces of the ocean have been mapped—and not surprisingly, many of these higher resolution portions lie along the world’s shipping lanes.

Another way to see this clear difference in resolution is through Google Maps:

As you can see above, these shipping lanes running through the Pacific Ocean have been mapped at a higher resolution that the surrounding ocean floor.

The Countries Mapping the Ocean Floor

The closer an area is to a population center, the higher the likelihood it has been mapped.
That said, many countries still have a long way to go before they have a clear picture of their land beneath the waves.

Here is a snapshot of how far along countries are in their subsea mapping efforts :

*An exclusive economic zone (EEZ) is the sea zone stretching 200 nautical miles (nmi) from the coast of a state.

Japan and the UK, which have the 5th and 8th largest EEZs respectively, are the clear leaders in mapping their ocean territory.

Piecing Together the Puzzle

Sometimes tragedy can have a silver lining.
By the time the search for Malaysia Airlines Flight 370 concluded in 2014, scientists had gained access to more than 100,000 square miles of newly mapped sections of the Indian Ocean.

Of course, it will take a more systematic approach and sustained effort to truly map the world’s ocean floors.
Thankfully, a project called Seabed 2030 has the ambitious goal of mapping the entire ocean floor by 2030.
The organization is collaborating with existing mapping initiatives in various regions to compile bathymetric information (undersea map data).

It’s been said without hyperbole that we know more about the surface of Mars than we do about our own planet’s seabed, but thanks to the efforts of Seabed 2030 and other initiatives around the world, puzzle pieces are finally falling into place.

Links :

Sunday, November 22, 2020

SP80 | Prototype sailing on Lake Geneva


SP80 presents the first images of its prototype sailing on Lake Geneva!
More information on the project to break the World Sailing Speed Record by reaching 80 knots: