Monday, January 14, 2019

Canada (CHS) layer update in the GeoGarage platform

75 nautical charts have been updated & 2 new charts added
see GeoGarage news
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Earth’s magnetic field is acting up and geologists don’t know why

Source: World Data Center for Geomagnetism/Kyoto Univ.

From Nature by Alexandra Witze

Erratic motion of north magnetic pole forces experts to update model that aids global navigation.

Something strange is going on at the top of the world.
Earth’s north magnetic pole has been skittering away from Canada and towards Siberia, driven by liquid iron sloshing within the planet’s core.
The magnetic pole is moving so quickly that it has forced the world’s geomagnetism experts into a rare move.

The movement of the Earth's magnetic poles are shown in this animation at 10-year intervals from 1970 to 2020.
The red and blue lines show the difference between magnetic north and true north depending on where you are standing. On the green line, a compass would point to true north.
credit : NOAA National Centres for Environmental Information.

On 15 January, they are set to update the World Magnetic Model, which describes the planet’s magnetic field and underlies all modern navigation, from the systems that steer ships at sea to Google Maps on smartphones.
Note : Actually, the release of the World Magnetic Model has been postponed to 30 January due to the ongoing US government shutdown.

Declination (magnetic variation) in region of north pole at 2015.0 from the World Magnetic Model .
Red - positive (east), blue - negative (west), black - zero. Contour interval is 5°.

The most recent version of the model came out in 2015 and was supposed to last until 2020 — but the magnetic field is changing so rapidly that researchers have to fix the model now.
“The error is increasing all the time,” says Arnaud Chulliat, a geomagnetist at the University of Colorado Boulder and the National Oceanic and Atmospheric Administration’s (NOAA’s) National Centers for Environmental Information.

Earth Magnetic Field Declination from 1590 to 1990
source USGS

The problem lies partly with the moving pole and partly with other shifts deep within the planet.
Liquid churning in Earth’s core generates most of the magnetic field, which varies over time as the deep flows change.
In 2016, for instance, part of the magnetic field temporarily accelerated deep under northern South America and the eastern Pacific Ocean.
Satellites such as the European Space Agency’s Swarm mission tracked the shift.

By early 2018, the World Magnetic Model was in trouble.
Researchers from NOAA and the British Geological Survey in Edinburgh had been doing their annual check of how well the model was capturing all the variations in Earth’s magnetic field.
They realized that it was so inaccurate that it was about to exceed the acceptable limit for navigational errors.

Mag.num - Model of the geomagnetic core field, based on Swarm satellite and observatory data Vertical component of the Earth's Magnetic Field at CMB.
(GFZ Potsdam)

Wandering pole

“That was an interesting situation we found ourselves in,” says Chulliat.
“What’s happening?”
The answer is twofold, he reported last month at a meeting of the American Geophysical Union in Washington DC.

First, that 2016 geomagnetic pulse beneath South America came at the worst possible time, just after the 2015 update to the World Magnetic Model.
This meant that the magnetic field had lurched just after the latest update, in ways that planners had not anticipated.

Second, the motion of the north magnetic pole made the problem worse.
The pole wanders in unpredictable ways that have fascinated explorers and scientists since James Clark Ross first measured it in 1831 in the Canadian Arctic.
In the mid-1990s it picked up speed, from around 15 kilometres per year to around 55 kilometres per year.
By 2001, it had entered the Arctic Ocean — where, in 2007, a team including Chulliat landed an aeroplane on the sea ice in an attempt to locate the pole.

This animation shows changes in Earth's magnetic field from January to June 2014 as measured by ESA's Swarm trio of satellites.
The magnetic field protects us from cosmic radiation and charged particles that bombard Earth, but it is in a permanent state of flux.
Magnetic north wanders, and every few hundred thousand years the polarity flips so that a compass would point south instead of north.
Moreover, the strength of the magnetic field constantly changes -- and it is currently showing signs of significant weakening.
The field is particularly weak over the South Atlantic Ocean -- known as the South Atlantic Anomaly.
This weak field has indirectly caused many temporary satellite 'hiccups' (called Single Event Upsets) as the satellites are exposed to strong radiation over this area.

In 2018, the pole crossed the International Date Line into the Eastern Hemisphere.
It is currently making a beeline for Siberia.

The geometry of Earth’s magnetic field magnifies the model’s errors in places where the field is changing quickly, such as the North Pole.
“The fact that the pole is going fast makes this region more prone to large errors,” says Chulliat.

To fix the World Magnetic Model, he and his colleagues fed it three years of recent data, which included the 2016 geomagnetic pulse.
The new version should remain accurate, he says, until the next regularly scheduled update in 2020.

 Annual rate of change of declination for 2015.0 to 2020.0 from the World Magnetic Model (WMM2015).
Red –easterly change, blue – westerly change, green – zero change. Contour interval is 2’/year (1/30th of a degree), white star is location of a magnetic pole and projection is Mercator

Core questions

In the meantime, scientists are working to understand why the magnetic field is changing so dramatically.
Geomagnetic pulses, like the one that happened in 2016, might be traced back to ‘hydromagnetic’ waves arising from deep in the core.
And the fast motion of the north magnetic pole could be linked to a high-speed jet of liquid iron beneath Canada.

The jet seems to be smearing out and weakening the magnetic field beneath Canada, Phil Livermore, a geomagnetist at the University of Leeds, UK, said at the American Geophysical Union meeting.
And that means that Canada is essentially losing a magnetic tug-of-war with Siberia.
“The location of the north magnetic pole appears to be governed by two large-scale patches of magnetic field, one beneath Canada and one beneath Siberia,” Livermore says.
“The Siberian patch is winning the competition.”
Which means that the world’s geomagnetists will have a lot to keep them busy for the foreseeable future.

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Sunday, January 13, 2019

All aboard the Flat Earth cruise – just don’t tell them about nautical navigation

“Though there are varying models within the flat earth community, the most commonly depicted model of our earth is that of a circular disk with Antarctica serving as an ice wall barrier,” the organization writes in its FAQ section.


From The Guardian by Adam Gabbatt

Flat earthers, who believe the Earth is a large disk, may be shocked to find the ship’s navigation is based on a spherical planet

"Flat Earth" type nonsense isn't new. This 1938 map depicts an "inspirational vision" suggesting the world's axis would shift, resulting in massive climate change, as well as lifting up of some bodies of land, and a submerging of others. 

A group of people who believe the Earth is flat have announced their “biggest, boldest, best adventure yet”: a Flat Earth cruise scheduled for 2020.

 Tim O'Brien painting

The cruise, organized by the Flat Earth International Conference, promises to be a lovely time.
Flat earthers – who include the rapper B.o.B. and reality television person Tila Tequila – will be able to enjoy restaurants, swimming pools and perhaps even an artificial surf wave.

Vniversale descrittione di tvtta la terra conoscivta fin qvi. Ferando Berteli, 1565,
based on an earlier map by Giacomo Gastaldi
(source LOC)

There’s just one problem for those seeking to celebrate the flatness of the Earth.
The navigational systems cruise ships, and other vessels, use rely on the fact that the Earth is not flat: theoretically puncturing the beliefs of the flat Earth crowd.

 This iconic image speaks volumes.
To many it underscores the vastness of space, the loneliness of the cosmos and how fragile our home planet really is.
Entitled “Earthrise,” it was taken by astronaut William Anders during an orbit of the moon as part of the Apollo 8 mission.
Apollo 8 was the first manned mission to the moon, which entered the Moon’s orbit on Christmas Eve 1968.
That evening, the astronauts onboard held a live broadcast, in which they showed pictures of the Earth and moon as seen from their spacecraft. Command Module Pilot Jim Lovell said, "The vast loneliness is awe-inspiring and it makes you realize just what you have back there on Earth."
The astronauts ended the broadcast with the crew taking turns reading from the book of Genesis.

“Ships navigate based on the principle that the Earth is round,” said Henk Keijer, a former cruise ship captain who sailed all over the globe during a 23-year career.
“Nautical charts are designed with that in mind: that the Earth is round.”
Keijer, who now works as a forensic marine expert for Robson Forensic, said the existence of GPS, the global positioning system, alone is proof that the Earth is a sphere, not a flat disc. GPS relies on 24 main satellites which orbit the Earth to provide positional and navigational information.
“The reason why 24 satellites were used is because on the curvature of the Earth,” Keijer said.
“A minimum of three satellites are required to determine a position. But someone located on the other side of the Earth would also like to know their position, so they also require a certain number of satellites.
“Had the Earth been flat, a total of three satellites would have been enough to provide this information to everyone on Earth. But it is not enough, because the Earth is round.”



Proof of the sphericity of the Earth advanced by Pliny the Elder 
(and not by Aristotle, as is often said.)
Low-resolution digitization of a figure published in the book Voyages des Astronomes français à la recherche de la figure de la terre et de ses dimensions by Abbé J. Loridan (Desclée, de Brouwer et Cie, Lille, 1890).

While there are different theories within the Flat Earth community, the core belief is the Earth is flat.
The FEIC claims that after “extensive experimentation, analysis, and research”, its adherents came to believe the Earth is not a sphere.
A common model offered for the exact topography of the Earth is that it is a large disk, surrounded by “an ice wall barrier” – Antarctica.

 credit : RT composite

The Flat Earth Society, which is not connected to the FEIC, has suggested that “the space agencies of the world” have conspired to fake “space travel and exploration”.
“This likely began during the cold war,” the Flat Earth Society says.
“The USSR and USA were obsessed with beating each other into space to the point that each faked their accomplishments in an attempt to keep pace with the other’s supposed achievements.”

"The Roulette Wheel Earth Theory" by Orlando Ferguson (1893)
That awkward moment when the flat earth isn’t even flat.
In contrast, the Square Earth Theory is based on its formulator's novel interpretation of certain Bible passages, dependent on a belief that God is incapable of symbolism, metaphor, and allegory.
This theory would presumably have no gravitational problems as those would be taken care of by God.

 New correct map of the flat surface, stationary earth
Other TitleWhen reading map lay it flat on table
Contributor Names : Abizaid, John George, 1868-
source : LOC

The FEIC did not respond to requests for more information on the Flat Earth cruise.

"Not amount of evidence will ever persuade an idiot"
Mark Twain quote

The organization could potentially try to staff the cruise ship with a crew which does not think the Earth is round, but Keijer said that would be difficult.
“I have sailed 2 million miles, give or take,” Keijer said.
“I have not encountered one sea captain who believes the Earth is flat.”

Fantasy map of a flat earth by Antar Dayal

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Saturday, January 12, 2019

So close! SpaceX fairing test ends with narrow miss of ship's net

SpaceX has been attempting to recover the fairings from the Falcon 9 rocket with a net-carrying ship, named Mr. Steven, in hopes of reusing them.
In the latest test, it narrowly missed the net. 


Commercial rocket company SpaceX has built its business model around recovering as much of its equipment as possible after each launch.
Reused rockets save SpaceX tens of millions of dollars for each flight, relative to single-use operations, and that savings can be passed on to its customers.  

To make recoveries possible, SpaceX has developed several novel methods for retrieving components at sea.
It has two autonomous deck barges that serve as offshore landing pads for booster rockets, and it has recovered multiple boosters after launch from its Cape Canaveral site.
One recent at-sea recovery made history: on December 3, a SpaceX orbital-class booster rocket became the first of its kind to make three full round trips, thanks to a successful deck barge landing.

SpaceX is also developing a specialized workboat to retrieve rocket nose cone fairings - the high tech aerodynamic shells that surround the payload during launch.
This unusual boat, dubbed Mr. Stevens, is intended to work like a catcher's mitt.
It is a fast crewboat retrofitted with a large net above its back deck, and its role is to maneuver underneath a fairing as it falls towards the sea.
(The fairings are equipped with parachutes, slowing their descent.)


So far, the catching tests have not been successful, but the but the boat has still managed to recover the fairings from the water for later reuse.
After the Mr. Stevens missed two fairings from a live launch last year, SpaceX CEO Elon Musk said that the "plan is to dry them out and launch again. Nothing wrong with a little swim."

In another recent test, a helicopter dropped a fairing from altitude so that the Mr. Stevens could make an attempt at a catch (top).
The effort was not successful, but the boat came within feet of landing the fairing.
Musk has previously said that each fairing is worth $6 million, raising the prospect of significant savings from recovery and reuse.

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Friday, January 11, 2019

Accident research highlights concerns over technology use


From Marimec by Gavin Lipsith

Technical failures have been identified as the immediate cause of 7.9% of maritime accidents analysed in a study spanning more than 600 incidents over 15 years.

The study by the Seafarers International Research Centre (SIRC) at Cardiff University looked at 693 accident investigation reports from the UK, Australia, the US, New Zealand, Germany and Denmark between 2002 and 2016.

Numbers of accident investigation reports by country of origin

It placed inadequate risk management as the leading cause of accidents, representing the immediate cause in 17% of cases and a contributory cause in 27.1%.


Technology featured prominently in accident reports, with technical failures the sixth most frequent immediate cause.
But ineffective use of technology was a bigger concern, noted as either an immediate or contributory cause in 115 cases (16.6%) compared to just 80 cases (11.5%) for technical failures.

As an example of a technical failure, the report cited the engineroom fire on board anchor handling tug/supply vessel Maersk Master in 2008.
The water mist system did not start automatically (because of inappropriate placement of smoke and heat detectors) and could not be engaged immediately by using the control panel by the engineroom entrance.

 Credit: The causes of maritime accidents in the period 2002-2016
by Acejo, I., Sampson, H., Turgo, N., Ellis, N., Tang, L. (November 2018)

The report differentiates between ineffective use, when technology has not been used to its full potential, and inappropriate use, when it had been misused.
In accidents involving collisions, ineffective and inappropriate use of technology combined were the leading contributory cause, present in 31% of cases.

When Spirent took part in the STAVOG project to analyse the impact of GPS disruption on sea vessels, it found low-level interference could degrade signals, causing positioning readings to be out by up to 270 metres.

An inappropriate use of technology was highlighted as a cause of the collision between general cargo vessels Francisca and RMS Bremen in 2014.
The officers on watch on both vessels failed to verify GPS positions, which were in fact false as the result of a technical fault, by means of another system (such as radar) or by sight.

Other noteworthy causes include inadequate training or experience (a factor in 16.3% of cases), inappropriate or ineffective maintenance (12.1%), poor design (10.9%) and lack of manufacturer guidance (4.2%).

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