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Datum transformation is and will be an ongoing headache for map makers.
In the cited situation - the World Magnetic Model does contain a component intended to compensate the geomagnetic field changes, The component must not be tracking reality well enough.

The differences between GDA and WGS84 come from a different source. GDA moves with the Australia, while WGS84 moves with IERS Reference Meridian, 5.3 arc seconds or 102 metres (335 ft) east of the Greenwich meridian at the latitude of the Royal Observatory.

The Geocentric Datum of Australia (GDA94) was the official geodetic datum before GDA2020. It was adopted nationally in January 2000. GDA94 replaced the Australian Geodetic Datum 1966 (AGD66) and Australian Geodetic Datum 1984 (AGD84). The standard map projection associated with GDA94 is the Map Grid of Australia 1994 (MGA94), a transverse Mercator projection that conforms to the internationally accepted Universal Transverse Mercator Grid system.

GDA94 is a coordinate reference system whose origin coincides with a determination of the centre of mass of the earth, hence the term ‘geocentric’. GDA94 is a ‘plate-fixed’ or ‘static’ coordinate datum based on the International Terrestrial Reference Frame 1992 (ITRF92), held at the reference epoch of 1 January 1994.

I haven't walked the seashore. I haven't examined the sediments (and never will now, apparently). I'm certainly not the bearer of an archeology sheepskin from some exalted university.

But ...

http://www.independent.co.uk/n...

http://www.independent.co.uk/i...

Does anyone see more than two prints in any sort of logical and likely walking pattern? You know, one in front of the other, left foot, right foot? No, I didn't think so.

"Of the 50 or so examples recorded, only around a dozen were reasonably complete - and only two showed the toes in detail. Tragically, although a full photogrammetric and photographic record has been made, all but one of the prints were rapidly destroyed by incoming tides before they could be physically lifted."

That's odd: EVERY bare foot print I've ever seen clearly showed the toes (even Bigfoot's!). And how curious, that "footprints" cast in rock-hard sediment that has survived for a million years beside a seaside that's repeatedly changed depth over the milleniums .. suddenly are totally and almost completely destroyed by the very next incoming tide? How .. unfortunate.

The Happisburgh geology (readily available with the most trivial search) also does not support this. The beach surfaces and their underlying sedimentary structure are NOT a million years old.

https://www.bgs.ac.uk/landslid...
http://books.google.com/books?...

No, I'm sorry, I'm not buying this. Someone was seeing what they wanted to see.

Not sure if you're aware of this, but there are plenty of places in the world where methane is dissolved naturally into the groundwater. Here's a page relating to a methane survey in the UK, and here's one from Alberta, Canada. There are plenty of other gasses in groundwater such as CO2 and radon, but most of the other ones aren't flammable.

If you want to make the case that methane in someone's tapwater was *caused* by artificial fracking, there's more to it than simply observing that the methane occurrence post-dates the fracking operations. You need to know what the "normal" level is, and sometimes that can be quite high, to the point that you have to properly vent your well or risk an explosion. Even drawing down the groundwater (e.g., by overpumping a water well) can increase the amount of natural methane flowing from the surrounding rocks. The water well owners could have triggered the problem themselves by improper well design and/or use. Anecdotes like "my water didn't used to have methane like this until the fracking started" are meaningless without looking at the details. It has to be studied carefully.

No reason to be there?
What about the Caspian pipeline?
http://en.wikipedia.org/wiki/Trans-Afghanistan_Pipeline

What about rare metals?
http://www.bgs.ac.uk/afghanminerals/raremetal.htm

What about the fact that Iran is sandwiched between Iraq and Afghanistan?
In military parlance it's referred to as a pincer movement
http://en.wikipedia.org/wiki/Pincer_movement

> I might add to that a natural volcano eruption produces so much CO2, that our silly civilization cannot produce in a half a century.

http://www.bgs.ac.uk/downloads/start.cfm?id=432

Every volcano on earth put together releases 1% as much CO2 per year as humans do.

I prefer to believe that you were quoting a source you trusted, rather than deliberately trying to cloud the issue. Now you know something important about that source's trustworthiness. Reason from there to an assessment of that source's motives.

"Earth's climate swings hotter-colder-hotter-colder."

Yes. Yes it does. It does so seasonally. It does so on El Nino / La Nina decadal scale. It does so on ~100k glacial/interglacial scale. It does so on ~250Ma "Icehouse/Greenhouse" scale. The question is, what cyclic process accounts for the average temperature increase of the last century or two? That's not clear at all. Furthermore, we can see secular, long-term changes that are pretty unique over geological time, such as the dramatic changes in the isotopic composition of the CO2 in the atmosphere that are caused by introducing so much "old" carbon into the atmosphere by burning fossil fuels.

And, no, humans do not put out less CO2 than one volcano. There are various estimates of human CO2 output, but it is more than 30 000 Mt/year and increasing. Total output from volcanoes is tougher to estimate, but is about 300 Mt/year on land [PDF]. Estimates for total output inclusive of underwater volcanism vary widely because of the uncertainties, but those totals are all less than 500 Mt/year [PDF], and some are less than 200Mt/year. Any way you slice it, this is far less than human input, let alone the comparatively minuscule amount from a *single* typical volcanic eruption. Even if you take some of the biggest eruptions in deep geological history, far in excess of eruptions that have occurred in historical times, humans still rank highly or on par with them. These sorts of "supereruptions" are rare things -- once in 100000 to million-year events. Think "Yellowstone Caldera" scale, which erupted about 2 million years ago. In effect, it's as if we're pumping CO2 into the atmosphere on the scale of some of these "biggest eruptions in Earth history" every single year, but without the mitigating effect of as much airborne ash or sulphate particles. An insightful calculation in the second article above is to use the well-studied, second-largest eruption of the last century as a measure -- the eruption of Mount Pinatubo in 1991 in the Philippines. It produced ~50 Mt of CO2 output. The equivalent of human CO2 output would be more than 600 Pinatubos a year (conservatively -- the article uses more realistic numbers and gets 700 Pinatubos/year).

You're promoting a "volcanoes produce more CO2 than humans" myth that has been shown to be wrong many times. It's not even in the ballpark. It's several orders of magnitude wrong. This does not inspire confidence.

I did manage to find one situation where your statement might be considered correct -- for a period of a few hours in a major volcanic eruption the output may be on par or greater than human CO2 output. It's explained in more detail in the second article above. But that's only briefly during the peak eruption. It's not sustained day-in, day-out, every hour over years like human outputs are. It would be pretty misleading to refer to that momentary comparison as if it was relevant in any general sense. Averaged over a year, those momentary volcanic spikes in CO2 output are pretty irrelevant.

While the UK does have the very occasional tremor, they're so minor that nothing more than a single roof tile has ever moved*.

Not true. The British Geological Survey issued an alert the day before yesterday, albeit not one of a high-priority "news flash" type since it was a mere 2.7ML. There are usually a couple above 3ML every year. There was a 5.2 magnitude in 2008.

I'm not trying to suggest even the record 6.1ML (or indeed the T5/F2 tornado in 2005) should be something that would cause great concern to a modern nuclear plant (I assume not).

There is an excess of FUD irrationality arising from Fukushima, and I'm generally pro nuclear power here in UK. But I respect that other people might have an informed, rational assessment of the risks involved and still sensibly arrive at a different view. And even the most rational of minds surely cannot help but observe the reminder that shit happens.

From the British Geological Society:

"The North Sea earthquake of 7 June 1931, with a magnitude of 6.1ML and with an epicentre offshore in the Dogger Bank area (120 km NE of Great Yarmouth), is the largest known earthquake in the UK. The felt area encompassed most of Britain, E of Ireland, the Netherlands, Belgium, N France, parts of NW Germany, Denmark and SW Norway. Damage in Britain was reported from 71 different places, with the strongest effects at Filey, where the top of a church spire was rotated. Bridlington, Beverley and Hull were also affected, with most of the damage affecting chimneys and plaster. A factory roof is reported to have collapsed at Staines (Surrey) and rocks or cliff collapse occurred at Flamborough Head and Mundesley, Norfolk. The earthquake was reported felt by a number of vessels in the North Sea and a woman in Hull died of a heart attack, apparently as a result of the earthquake."

There have been 5 earthquakes reported in Britain in the last 30 days, the largest being of magnitude 2.7. Two of these are associated with shale gas "fracking" near Blackpool.

Generally speaking though, the UK doesn't have damaging earthquakes, but it's incorrect to say that "nothing more than a single roof tile has ever been moved". *disengages pedant mode*

Interesting. On the west coast it does rain quite a bit, but last summer and this summer so far, we've had hardly any rain in Aberdeen (east coast). Maybe a couple of days rain a week when it's been at its worst in May. April was sunny as hell.

I've never even heard of a mudslide in the UK, so I don't know where you're getting that from (. Googling for "mudslide UK", I get 1) a cocktail recipe, 2 & 3) music albums, 4) something which seems to be just one of those pages that is there to catch search traffic, and the rest of the results are British newspapers reporting stories of mudslides in other countries..

Searching instead for "landslide" (since I'm not even sure I've heard the word mudslide before) does turn up some results, but it's mostly coastal erosion. I didn't realise we built our nuclear reactors in the sea.

"All hypotheses that the well water pollution is a natural source have been discounted over the past 5-10 years,"

Wrong.

Unless you've got a URL that disputes what this one says:

http://www.bgs.ac.uk/arsenic/bangladesh/reports.ht m

"13.1.4 Source of the arsenic

There is no doubt that the source of the As is natural, i.e., derived from 'ordinary' sediments by natural geochemical processes. The quantity of As present in groundwater (and adsorbed by the sediments) is simply too large to be derived from a discrete pollution source. Also its distribution across Bangladesh and West Bengal and with depth does not tally with a pollution source. There is also no need to postulate exceptional sources such as a particular mineralised area in the upstream catchment, as some workers have done for neighbouring West Bengal (Acharyya et al., 1999), although of course such areas may exist. This is one of the lessons that needs to be learned from the Bangladesh arsenic problem.

There is more than enough arsenic in most sediments to give rise to an As problem given the appropriate geochemical conditions for release and mobilisation. If all of the arsenic in a sediment containing 1mg As kg^-1 sediment dissolves in the groundwater, then the arsenic concentration would be 6000 micrograms/L or more, way above all drinking water standards. Both the average world and typical Bangladesh sediments contain several times this amount of arsenic. In other words, Bangladesh sediments do not appear to contain an exceptional amount of arsenic /in total/ yet give rise to exceptionally large groundwater arsenic concentrations. The high solid/solution ratio in aquifers and the great toxicity of arsenic mean that the contamination of groundwaters is sensitive to an imperceptible shift in the speciation of arsenic. A change of only a few percent in the partitioning of arsenic between sediment and water is sufficient to give rise to a significant groundwater arsenic problem."

So unless you've got some sort of documentation that trumps the British Geological Survey, I suggest you take a course in "rocks for jocks" (geology 101) instead of spewing your uninformed twaddle here.

--
BMO

But you must be on crack. "The Earth is currently in the same magnetic configuration..." Take a look at this: http://www.geomag.bgs.ac.uk/reversals.html and tell me the magnetic "configuration" hasn't changed for 100s of millions of years.

That supposes that

a) The data will be preserved. There is no particular reason why it should.

If people consider it important (and I know that the author of TFA is far from the only person who thinks that it will be an important historical record in the future) then they will preserve it.

CDs and DVDs with sections or complete dumps of the data on it are produced regularly. For all the people who say "but what about the technology to read them?" I say bullshit. Both formats are adequately described in paper publications that are likely to be preserved. There are plenty of people with interest in preserving the data. It will be possible for somebody in the future (assuming they have equivalent technical capability to our own) to follow those descriptions and produce machinery to decode a CD or DVD. Both formats are expected to be capable of being read with normal equipment in a hundred year's time if looked after reasonably well... I'd wager that with advanced kit (e.g. using multiple lasers of substantially shorter wavelength than nominal to produce a detailed 3-dimensional reflectivity map of the disc that can then be reconstructed to ideal state and read in a simulation of a normal player) well-preserved CDs and DVDs will still be readable hundreds of years into the future. That's long enough for the historians of the era to have realised the value of what they have and start making duplicates.

b) The data will be understood. There are many languages of the past that we cannot understand. The same will probably will be true in the future.

Most of Wikipedia is written in English. English is the modern equivalent of Latin; it is the language in which most international commerce is undertaken, in which scientific and philosophic thought is exchanged and in which the vast majority of the world's significant cultural output is produced. These three attributes enabled knowledge of Latin to survive the so-called dark ages, and will likely enable knowledge of modern English to perpetuate thousands of years into the future also. We haven't allowed the language of Virgil to die out; why would we allow the language of Shakespeare to do so?

c) They will have an interest. For us our particular time is interesting, but are we also interested in, say, the political views in the Kassite dinasty in Mesopotamia?. And that period took four centuries, surely many interesting things happened. The quantity of data to analyze in a distant future may make all but big overviews too much for a human mind. Something like "after the Middle-Ages, the so-called Modern-Ages (1500-2500) developed, with humanity developing a primary state of technology, but still lacking a conscience of ecology. The natural resources were depleted and the balance of Earth was tipped a bit too far, ending in the natural disasters that gave birth to the Interregnum (2500-2900)."

Like it or not, we live in interesting times. The development of mass industry, weapons of mass destruction and global near-instantaneous communication have changed the world significantly. We (in the developed countries) are, on a large scale, substantially different from the people of just fifty to a hundred years ago. And unless you expect a Vinge-like Singularity to occur, the rate of change can't really continue as it is. We're living on a rather steep piece of the slope of technological capability, and I expect it will shallow-out in the next fifty or so years. Late-19th to mid-21st century history will likely be a heavily studied period in the future.

I mean, nobody will be particularly interested in what the US thought about the obesity problem, compared to say, what the Germans did, in the beginning of the 21st century.

No? How people ate in the past is a serious area of study now... why should it not be in the future?

...when a reversal happens, we're left without the Earth's magnetic field, which protects us from lethal cosmic rays...

A quick google shows that this incorrect. The atmosphere continues to block most incoming radiation even during those times when the magnetic field has completely collapsed. 'Cosmic ray' is not the right choice of wording here, either-- very little of the incoming radiation meets the definition of cosmic ray, which is good because neither the magnetosphere nor the atmosphere provides much protection against true cosmic rays.

Magnetic field reversals coincide with mass surface life extinctions

This is completely incorrect. There have been numerous studies to look for correlations between pole reversals and extinction rates; no significant correlations have been found by any of the serious researchers (though it is currently fashionable among the half-baked set to claim otherwise--- the fun of Chicken Little Syndrome).

Here's one reputable source: the British Geological Survey. Google will reveal thousands more, but you'll need to sort out which ones are authoritative and which suffer from CLS.

Ok, didn't check that bit - it was from memory.

Looking on Google again I found what I'd been think of. It's the Geodynamo if anyone want to look for it.

"Currents flowing in giant loops through the earth's core."
You're pretty much correct there on how they think it happens.

Basically the guy noticed that the direction the molton core convects is different in some places than others. And it changes the way the magnetic flux acts.

When the convects in one direction, the flux goings in one direction; when it convects in the other the flux reverses the direction (which is what I was thinking of when I said about the North/South poles).

Lots of pretty pictures on a few sites talking about the Geodynamo, I'm sure there'd be more stuff around if anyone wants to look for it.

http://www.psc.edu/science/Glatzmaier/glatzmaier.h tml
http://www.psc.edu/research/graphics/gallery/geody namo.html

The first two animations on that page show fairly when what's happening.
The core of the Earth is rather chaotic in terms of which direction the convection is happening in and therefore which direction the magnetic flux is in (this is what I'd been thinking of).
These bits change over time and move around to different points under the Earth's surface (think hotspots which move and cause chains of volanos which are all dormant apart from the ones at the end).
Which direction the flux moves in overall is essentially a complex summation of where these lines of flux are moving.
During the reversal lots of areas of convection change direction and change the direction of their flux. As they do so the overall lines of flux move and weaken, until they swap around.

This is quite an informative page on magnetic field reversals, and it talks about the Geodynamo at the end.
http://www.geomag.bgs.ac.uk/reversals.html

Obligatory Wikipedia links:
http://en.wikipedia.org/wiki/Magnetic_polarity_rev ersal
http://en.wikipedia.org/wiki/Geomagnetic_reversal
http://en.wikipedia.org/wiki/Geodynamo
http://en.wikipedia.org/wiki/Dynamo_theory

Ah, no. You can look here and see for yourself. The number of major earthquakes isn't even above average. Of course the average they give for earthquakes over 7.0 is only based on observations since 1990, so you can look here and do your own comparison. You'll see that the average number of major earthquakes was actually lower for the first four years of the new millenium than for quite a few other four year periods.

The UK & US geological survey people kick out the magnetic charts. Look herefor starters.

The link in my parent post will just give you a few minute's warning if you're about to die of solar radiation because the field is goofed up. Sorry guys.

Pilots only need a very gross measurement of magnetic field. They really only care about the field coming from the earth's core. We measure the field coming from the core and the rocks then remove the core's field. The field from the rocks is much smaller, but can tell you a lot.

Magnitude 4.8 (yeah, that would be a nice jolt), in Dudley, W. Midlands, at 23:53 GMT on 22 Sep.