Map continuity

[BigIrish77]

So, the story I am working on takes place in the real world, and at one point involves a small but inhabitable-sized island that will eventually crumble into the sea, around the mid 1700's (it's part of a back story).

It's an island that does not exist in real life.

My question is, how do I account for that island never having been on a map before it crumbled?

Or do I even need to worry about that?

 

[Abernovo]

The coast of Australia was not accurately mapped until the 18th Century, when Captain Cook travelled along it and joined the dots of a partially discovered land (New Holland?). If a small islands like Australia (and New Zealand) can be missed, what else could have been?

Also, just because it wasn't mapped by European cultures, doesn't mean it didn't exist. The Americas were there before Columbus, the Vikings, or (tenuously) Brendan ever set sail. Finally, some islands were mapped, but incorrectly. There is the case of a British warship sinking at the end of the 18thC because of poor navigation charts - a large rock, known to be a shipping risk, was misplaced on a map. I can't remember the name, but do recall the losses to be massive, and the incident led to a more organised Admiralty mapping office.

Don't worry too much. Write the story. It's not one hundred per cent our world, anyway, unless you're writing a non-fiction historical account. Your island is just another character. Good luck.

 

[Mr Orange]

Make it in an isolated part of the Pacific or Atlantic and I don't think there will be any issue. You could even invent an ancient map that did happen to show it.... there were plenty of maps showing foreign lands before western Europe got there after all...

 

[alchemist]

Even aside from the issue of maps being incomplete in those days, there's no problem incorporating a fictional island into a real world setting. It shouldn't be something to worry about.

 

[chrispenycate]

How big is 'inhabitable sized'? If it can support a community of a few hundred and isn't on the main shipping routes it'll be marked with the same symbol as a reef; steer clear, danger. If it's lucky it might get a 'possible source of fresh water' sign.

If you want a community of a couple of hundred thousand with industry more complex than 'net weaving' and 'canoe building', this might be a trifle more difficult, but remember European ships generally stayed within eyesight of the coast (which, admittedly, is where the vast majority of islands is found, so a little volcanic blip, if it wasn't on the way from somewhere to somewhere else (or a 'pirate' base preying on ships that were) would be easily overlooked until you get satellite surveillance, or at least regular air travel.

 

[Mr Orange]

as alchemist quite rightly points out, you're making up a fictional island so who cares if it doesn't appear on non-fictional maps...

of course if its off the main trade routes by a good distance then it is very likely it wouldn't have been visited before 1700, unless someone was very lost...

expanding on my previous post, if it's a back story you could invent a fictional portugese ship that mapped it after getting lost and then when the area was mapped in more detail (after 1700), it was gone...

 

[Bowler1]

Very recently there was an earthquake in Northern India, Pakistan or somewhere near there. Anyway, an island popped up right out of the sea bed, and this is common in the area. Most of these wash away after a ferw years, being just sand and rubble, and also as the land settles back down long after the earthquake. I read this on the BBC news, check it out!

BBC News - Pakistan quake island off Gwadar 'emits flammable gas'

I know, cool or what!

 

[alchemist]

Very cool, although this...

"There were dead fish on the surface. And on one side we could hear the hissing sound of the escaping gas," Mr Baloch said.
Although they couldn't smell gas, they did put a match to the fissures from where it was oozing, and set it on fire

... sounds like the opening paragraph of a Darwin awards story

 

[Mirannan]

Another way an island could disappear is by sea level rise; quite a few Pacific islands have a maximum height of just a metre or two above sea level and might well disappear if sea level rose that much. The island nation of Tuvalu is one of them, IIRC. (which may actually be several islands, but you get the point...)

 

[ZombieWife]

I don't think it's a big deal, but of course my mind goes to fun places thinking about it. What if nobody mapped it or knew of it except for ONE GUY and he drew a map and that map was hidden away and whoahhhh! Adventure time!

 

[nightdreamer]

Don't worry about it. There are still map errors and islands "disappear" from time to time, so yours isn't that unusual. Pacific Island, Bigger Than Manhattan, Vanishes : Krulwich Wonders... : NPR

 

[Bowler1]

"However, their "Hey, it's missing!" report made little impression in cartographic circles. Ham enthusiasts and mapmakers apparently don't talk much."

Maybe they should have boosted their signal some more?

 

[Chel]

Here I was thinking "Map Continuity" would be about why maps in trilogies hardly ever update between books, even if the story itself might demand it - such as wars resulting in new borders being drawn or cities being razed to the ground and such.

I'm not complaining, mind you! It was an interesting topic even if I have nothing else to add than a possible derailing-hook.

 

[jastius]

all sea coasts erode.. many towns and villages have disappeared off the map of britain..



The Holderness coastline suffers the highest rate of coastal erosion in Europe: 5 feet (1.5 m) a year on average or 2 million tonnes of material a year.[2] Some of this is transported by longshore drift with about 3% of material being deposited at Spurn Head spit, to the south. The growth of Spurn Head is demonstrated by a series of lighthouses that have been built on the point. It is thought that approximately 3 miles (5 km) of land has been lost since the Roman era, including at least 23 towns/villages, including Ravenspurn. The Holderness coastline is susceptible to erosion due to the long north-easterly fetch, allowing for powerful waves, and the softness of the geology that make up the cliffs. Holderness is also a former bay that was filled in during the last ice age and is now made up of chalk/glacial compounds that are easily eroded such as boulder clay.

Aldbrough, Holderness. Coastal erosion.


All the villages affected by the erosion are located on the north side of the estuary of the River Humber. The area stretches from Flamborough Head (high chalk cliffs, just north of Bridlington) down to Spurn Head (sand spit, on above map). Villages such as Ravenser, which sent representatives to the parliament of Edward I, have totally disappeared.
(from...)
Holderness - Wikipedia, the free encyclopedia

volcanic islands erode quickly and can disappear..
Surtsey (Icelandic, meaning "Surtr's island") is a volcanic island off the southern coast of Iceland. At 63.303°N 20.6047°WCoordinates:

63.303°N 20.6047°W Surtsey is the southernmost point of Iceland. It was formed in a volcanic eruption which began 130 metres (426 ft) below sea level, and reached the surface on 14 November 1963. The eruption lasted until 5 June 1967, when the island reached its maximum size of 2.7 km2 (1.0 sq mi). Since then, wind and wave erosion have caused the island to steadily diminish in size: as of 2002, its surface area was 1.4 km2 (0.54 sq mi).[1]The eruption that created Surtsey also created a few other small islands along this volcanic chain, such as Jólnir and unnamed other peaks. Most of these eroded away fairly quickly.
from..
Surtsey - Wikipedia, the free encyclopedia


rising sea levels can flood over low lying areas..
Climate change 'will wreak havoc on Britain's coastline by 2050' | Environment | The Observer


flooding for hydroelectric dams or tidal basins can flood out low lying areas..
Environmental and Social Issues of the Three Gorges Dam in China


or for shipping locks.. these like the panama canal can in some instances be emptied out again.

The Lost Villages - Wikipedia, the free encyclopedia



lands can sink.. either from soft alluvial soil

Venice's Sinking Map From Satellite Data Teases Apart Natural, Man-Made Influences (PHOTOS)


mining and groundwater loss can cause sinkholes...

That sinking feeling: Villagers shocked as vast spaces of land are swallowed up by 20 huge sinkholes in less than five months | Mail Online


using a combination of these could make an island disappear in your story effectively and with the tides reappear..

and until the income tax thing came in with the domesday book, it was the responsibility of the landowners to map.

 

[BigIrish77]

Wow, this thread blew up in a good way! I didn't expect this many responses in such a short time!

Looking at all of these replies, I suppose some back story might be in order.

Without giving too much away, the island was basically a barren land mass in the middle of the ocean just of the southeast coast of Ireland. Then, it was struck with a meteor in the 1600's and within a year became lush with vegetation. So people moved to it. In the mid 1700's, the island crumbles in on itself (my story explains how), thus why it is no longer around.

Now, my girlfriend has asked if it was possible to have the meteor create the island. Basically, in that scenario, it would crash into the ocean and force land upward. This would be a reason it was never mapped before - it wasn't there (right along with bowler1's line of thought). But, a meteor with size and force enough to do that would cause catastrophic events, would it not?

As for the size of the island, it would only have to house a few hundred to maybe a thousand families from the 1600's - mid 1700's time, so grand scales of industrial structures would not be in the equation.

Thank you for all of the input and look forward to the future replies as well!

EDIT: Changed "villagers" to "families," as that is more accurate to what I meant.

 

[nightdreamer]

I would have more trouble with the meteor creating the island than there just being an extra one there that has since vanished. I sometimes toy with a plot that involves a large island off the coast of Cornwall, which has since "faded away" in this reality, and I could argue that along with that fading so did all references to it. But that's fantasy, and I don't know how far you intend to go in that direction.

 

[BigIrish77]

Yea, the more I got to looking at what happens when a meteor hits the earth, there is more destruction than anything else.

So, I am gonna go with the "it was there, and they just did not map it" line.

 

[Aleph]

Yes, I've read several stories of the "Island off the Coast of Ireland that Sinks Under The Sea", it's a common enough fantasy trope and I can't recall anyone explaining it, so you shouldn't have too much trouble. (One version: The island was a Whale)

My favourite "island" book is the Drowned Lands (does anyone remember that book. Is a slim volume but so well written.) It had Stonehenge being built because of a prophecy the island was going to drown, suitably creepy and magical.

A meteor the size of a small island would probably cause a global extinction event, similar to what killed off the dinosaurs!

 

[BigIrish77]

So, I did a little research, and it looks like I am going to need to have an island size of about 100 or so square kilometers to have the population density I am looking for (~4000 inhabitants).

Too big? Or still possible.

I suppose I could squeeze them in a bit if need be, but I don't see it gong much below 80 square kilometers for ~4000 people.

 

[alchemist]

South east of Ireland is basically Wales and Cornwall. Those shipping routes have been busy since shipping began and I think it very unlikely an island would stay undiscovered. South west is a different matter...