Submarine cables at risk from sea water, boffins warn. Wait, what? University of Wisconsin-Madison boffins have warned submarine cable owners that their landing stations and onshore cables are at risk from rising sea levels. “So what? Submarine cables are meant to get wet!” you might say – yes, but the onshore infrastructure isn't protected against a soaking like a cable designed to exist at …
Sea level rises slowly, and there aren't a whole lot of these cables so they could easily take them offline to move/protect infrastructure as needed. This is like item number 37,552 in the order of importance of things we should be worried about with sea level rise.
I'm assuming you're not familiar with what goes into making a landing station - it most certainly is not easy to take a submarine cable off line and move it. (Hooking it with a ship's anchor and dragging across the seabed doesn't count).
Apart from the new infrastructure build required to replace the landing station, replacing/extending the landing section of the cable would be quite a significant task as it is usually comprised of the heaviest and most highly armoured cable in the system. There's also more than a couple of hours worth of setup and certification work needed once the new landing station(s) have been built - more like days or weeks.
Oh, and don't forget that the cable manufacturer will want to do a feasibility study on your new build, as in some cases there may be an impact on cable capacity - normally the first amplifier is placed on the assumption the landing station is not going to move - if you extend the cable too much an additional amplifier may be required, which will change the power feeding needs of the cable and introduce more noise and distortion to the optical signals. This in turn may mean you are restricted to 10G or 40G/wavelength rather than 100G, 200G or 400G, or perhaps you will not be able to use as many wavelengths.
Nobody is going to move anything. Fiber is all or nothing in most cases. Bends are a huge issue above 40ghz on smf, generally you hook up and test. The cable manufacturer won't be doing any studies, and I'd bet most of the ta stuff is 100ghz or less. I'm not aware of any feeds into my dc that are over 100. Still too finicky, and the termination equipment is outrageously expensive at 100.
Depending in what you can put down on the ocean floor as a repeater, every 30 klicks, I'd say any issues at a facility on the coast would be pretty simple to overcome by comparison. It's not like the coastal facility is a data center, it's just a switch/repeater to some inland dc.
" I'm not aware of any feeds into my dc that are over 100. Still too finicky, and the termination equipment is outrageously expensive at 100."
Most of the stuff I see going in now is 200Gb/s wavelengths and has been for a couple of years - 100G is actually getting pulled out and replaced by 200G by one of my customers - transponders occupy the same or less number of slots, power consumption is less and as a bonus you get twice the data rate per wavelength. I guess the difference is that I work with the same types of DWDM kit that goes on the end of submarine cables, not what goes into data centres - although that said, we do sell routers that will take 400G interfaces and we do now have DWDM transponders that can do 400G coming on to the market.
"Depending in what you can put down on the ocean floor as a repeater, every 30 klicks,"
Or maybe amplifiers rather repeaters, which are limited to their original design rate and protocol - the spacing is usually a compromise between the end-of-life capacity requirement from the customer and how to achieve that with the minimum number of amplifiers. Every amplifier requires 50 volts across it, so a long cable can require as much as 25kV to be supplied, which imposes problems of its own when moving this stuff around.
"It's not like the coastal facility is a data center, it's just a switch/repeater to some inland dc."
I've done work in several landing stations - they are more "just" a switch/repeater and have all included a variety of systems for breaking out sub-rate data streams for the various cable customers in addition to the basic cable terminal equipment - ie.the large and complex power feeding equipment, some form of optical routing/DWDM kit to terminate the fibres and the crucial station earth (just in case the sea earth fails for some reason). At least two of them have included one or more major PSTN switches in addition to data switching/routing kit - months to move, years to plan.
At least two of them have included one or more major PSTN switches in addition to data switching/routing kit - months to move, years to plan.
Not necessarily.. So a lot depends on the design, and ideally at the design stage, DR should have been a consideration. The basics would be the PFE (Power Feeding Equipment) and SLT (Submarine Laser Terminal) that drive the wet sections. So that's the stuff that may need moving or duplicating, ideally with bypass cabling already installed to an alternate site. One system I worked on had all the 'customer' kit hanging off fibres in London that connected to the landing station in Cornwall.
It gets more complicated with consortia cables where multiple providers may have their own access to fibres, especially on shorter distance/high fibre cables. Or being telecomms, if some bright spark (usually sales) says 'Hey, let's collocate some customer kit in the landing station!' and gets a contract signed before the planners have had a chance to educate them with the nearest cluebat.
But global warming isn't as bigger risk as storm surges given the timescale.
They don't have to move it, just build retaining walls around the facility. There are only a limited number of relatively small facilities, it wouldn't cost much (in relative terms, especially compared to trying to move them entirely) to build up sea walls and, eventually, turn them into small islands.
They don't have to move it, just build retaining walls around the facility. There are only a limited number of relatively small facilities, it wouldn't cost much (in relative terms, especially compared to trying to move them entirely) to build up sea walls and, eventually, turn them into small islands.
Yep. A newbuild office right next to a river in a flood plain did this. The developers quickly discovered that nobody would rent the place due to the fact that everybody living in the area knew that area flooded not infrequently.
Shortly thereafter, a team of blokes with some JCB's turned up and built a ~2 metre high earth bank around the building, and a ramp over it for vehicle access. It was then rented out shortly afterwards.
When the river inevitably flooded, the building was left sitting in an unflooded island, and a local place hiring out canoes did some unexpected and unseasonal hires. No reason the same couldn't be done for critical infrastructure.
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Salt water is not good for cables designed for normal duty. So as well as building the dykes round the equipment, you'd also have to replace the cables going inland. And you'd need to construct an access bridge or something. It's all presumably feasible, but costs real money.
"Sea level rises slowly"
Yes, but the report states that much of the expected damage will occur within the next 15 years.
"there aren't a whole lot of these cables"
The report is about all kinds of network infrastructure including "1,100 Internet traffic hubs – data centres, Internet exchanges and the like", which "will be surrounded by water within 15 years." as well as regular underground cabling and fibre. It's not just about subsea-infrastructure; that is only a small part of a bigger problem.
Most likely the first time the problem will become apparent will be during a storm surge or hurricane, which may knock out comms and data processing for a hinterland that is many times larger than the area hit by any flooding. There is also the issue of salt water ingres into coastal groundwater, which can occur without any obvious signs of flooding as such.
It might seem a small problem compared to other issues related to global warming, but widespread loss of comms during a localised extreme weather event could be disastrous.
Most likely the first time the problem will become apparent will be during a storm surge or hurricane, which may knock out comms and data processing for a hinterland that is many times larger than the area hit by any flooding.
That's already been tested. So in October 2012, Sandy rolled in to New York, and a decent chunk of the US East Coast. That caused extensive flooding and wave scouring risking transatlantic cable landings. From memory, there were some hits on AC-2, but other cables were fine. Downstream from there was a different story, ie flooding and power outages in NYC etc.
Properly designed landing stations shouldn't be that vulnerable though. Inshore, the wet bit is generally the most vulnerable given it's shallow. So that's usually more heavily armoured, and then buried, possibly with additional protection like protective matresses and/or concrete. That may terminate onshore in a concrete pit/chamber or run straight through to the landing station itself. But the wet side is still welll armoured and protected given it's carrying a LOT of DC to power the submarine repeaters. The landing station building may be a good few kilometers inland and easier to defend against flooding or power outages. Especially if it's in Hoboken, which is notorious for flooding anyway.
In a DR scenario, usual rules apply, ie you have diesel gensets flood-proofed and diesel tanks that won't suffer water (especially salt) ingress. But if the roads are flooded, getting refueled can be fun. And services downstream from the landing station may be isolated repeater/regen sites that aren't as well protected. Especially if they're some customer sites who don't necessarily follow telco 'best practices'. But generally because infrastructure cabling is underground, flooding or water ingress is to be expected and shouldn't be a problem.
1: Florida is sinking faster than sea level is rising
2: So is the entire Mississippi Delta
Both of those are believed to be due to the effect of glacier melt rebound effect (where the glaciers were, the squashed land is rebounding upwards. Land just beyond the end of the glaciers was pushed upwards and now it's sinking)
3: Chesapeake Bay is spectacularly vulnerable to sea level rise and it's already rising locally there far faster than the global average(*) thanks to changes in the the Atlantic conveyor current (Gulf Stream) and location.
(*) Local changes happen all over. Long term prevailing winds cause local levels to pile up without changing the global levels one iota and currents act like river valleys. In the case of Chesapeake Bay the localised effect of the Gulf Stream is a 3 foot lowering of local mean sea level vs it not flowing nearby.
4: Storm surges can really ruin your day and your infrastructure.
Florida and the Mississippi river delta are hardly just beyond the end of the glaciers, unless 1000 miles counts as "just beyond".
It may have reached further in previous ice ages (from which the rebound would have presumably already happened) but didn't even fully cover Minnesota and Wisconsin in the most recent one. It never got further than the southern edge of Illinois at any point in the Pleistocene.
So all these seaworthy cables terminate 1" above the shoreline?
In an environment near the ocean with tides and surges, I put all my equipment 1 " above the high tide mark?
Trust me. Back in the 80's/90's the main switchpoint Inland in Va or MD got flooded, took out communication on the East Coast for a day. It was weeks before full capacity was restored. I can assure you that lesson was not forgotten. An underground bunker seemed like a good idea at the time. Unfortunately the equipment was sitting in a foot or two of water, once it breeched.
Now this transatlantic stuff is totally over-engineered. I'd bet those cables terminate 20-30 ft above highest tide in sealed structures with massive pumps and backup systems. Tsunami might get it, but I'd bet even then they could have it online in a day or three..
Problems are usually more mundane, like the fiber cut 2-3 years ago in Roll,Az. Took out the fiber on both sides of the RR tracks doing some road work. Took out as in they had to run all new cable for the segment in the ground. That took some time, we routed dallas to chicago to la for over a week from phx.
It may have been over-engineered a few years a go but sea level rise and its effects are not linear, they are heavily fractal - New Orleans is a good example. Another is Dunwich in Suffolk a couple of storns over 100 years removed more than half the village and moved the coastline back the same distance its moved in the last 500.
And as for a Tsunami - well you may think they could get it back online in a day or three but when the a storm like this hits then there is unlikely to be any roads left and no power anyway as the grid will probably be taken out too, We dont have enough redundancy cos profits for real disaster management.
For New Orleans, it's not that the sea is rising faster than other areas (this is - hardly at all) that is the problem, it's that the land is sinking. It's built on weak sediment from the Mississippi river, not bedrock - this is to be expected. Time to move to "solid" ground (technically no such thing as it's all a thin crust on a bunch of molten core material).
it's that the land is sinking. It's built on weak sediment from the Mississippi river
It's also resting on a swampy floodplain that people are sucking all the water from - which makes the land drop, thus making the problem worse..
The same is happening in parts of China, India and Bangladesh.
"It's also resting on a swampy floodplain that people are sucking all the water from - which makes the land drop, thus making the problem worse."
I think the current record for subsidence caused by pumping fluids belongs to Los Angeles-Long Beach Harbor where parts of the Port of Long Beach sank as much as 29 feet due to pumping oil from the Wilmington Oil Field. The subsidence was eventually stabilized by injecting salt water as oil was removed.
In general, you're correct. Sea levels are rising -- but slowly. If one has any doubts, it's easy enough to check for one's self. NOAA has data for US tide gauges on line. They'll even do a linear fit and compute the rate of rise for you. Typically, it's about 7-10 inches a century. Hint: The two longest records are for The Battery in New York and San Francisco. For data on stations outside the US, try the Permanent Service For Mean Sea Level.
That said. Folks are prone to build infrastructure without sufficient allowance for worst case storm surge. Worst case storm surge in a strong tropical storm can reach 7 to 8 meters. (23-26 feet). And that's before allowing for tides and waves. I suppose that it's inevitable that sooner or later one of the stations will be flooded. But compared to the near certainty of occasional massive flooding and/or total destruction of seafront residential and commercial property every time a tropical cyclone makes landfall, the potential problem is not very large.
"Worst case storm surge in a strong tropical storm can reach 7 to 8 meters."
This.
At Avarua atoll one storm surge came through in the dead of night and silently took the entire population out to sea (The actual hurricane was 200 miles away). It was well above local treetop level so hanging onto any wasn't an option (it ripped most of them out anyway).
It was 3-4 weeks before all the survivors were located and rescued.
"Sea levels are rising -- but slowly."
Yes but the rate of rise is increasing. And the rate of the rate of rise is also increasing, and is expected to continue to do so. Expected sea level rise by 2100 is 60cm - 2m plus. Likely on the higher side of that from much of the recent analysis.
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Given what Musk tweeted, perhaps he could be used as aggregate in the foundations of any concrete pilings required. Or perhaps the arsehole's apologised by now - in which case he should make up for being such an idiot with a free ticket on his shiny new Dragon 2 capsules. Once they've been tested.
Although if Musk is really going to go big into his tunnel drilling company, why can't he just dig some really long tunnels under all the oceans, so that they fill up with water and lower the sea levels. Who wouldn't want to go from London to New York by underwater train? Nuclear powered, naturally.
It might be best to construct Thunderbirds 2 and 4 first though.
I suspect the key point in this is not the detail of the cables affected, but the timing. "You thought you there was no rush..."
And sometimes, "redundant" routing isn't. I remember, back in the Nineties, two US cable links, different operators, apparently totally independent, crossed a river on the same bridge, which fell down.
"Fancy fibre network with redundant links between two nodes. Unfortunately they were laid in the same ducting, so links not redundant when someone else trenches the street without checking what's in the ground..."
In the past I've worked with a transport system which had full protection at the optical layer - on two different wavelengths of the same DWDM system ie., not even different fibres in the same cable sheath which, if carefully chosen to be on opposite sides of the central strength member, can give a small measure of protection, but on the same fibre pair.
Cables in the ground are designed to stand in water. Pits fill with water.
Long haul telecoms cables will be armored - steel or gevlar . Several layers of plastic, Plus Steel Tape. Plus Gel or tape to swell and block any water that does get in. Search youtube with "Outer Sheath and Armor Removal Procedure for Interlocking Armored Cables" or similar terms to see the cables being worked on..
Cables in the ground are designed to stand in water. Pits fill with water.
In my (UK) experience, the legacy underground copper telephone cables - the major trunk cables with 100 pair / 200 pair - are polyethylene sheathed with a foil wrap as a moisture barrier, then a paper wrap, then the cores with PTFE insulation, and are filled with petroleum jelly.
These are pretty resistant to water, but the polyethylene does become porous over extended time periods.
The bigger problem is where joints are introduced, these are commonly sealed in a Polyethylene tube with liquid resin poured into formers at the cable entries, then wrapped in self-amalgamating tape and latterley heat-shrink tubing. These tend to lose their watertight properties quite quickly.
It's rare,in the UK for armoured cable to be used in ductwork.
Here in Australia the Telstra maintenance people often just wrap the stuff in a plastic shopping bag. Single use plastic shopping bags are in the process of being phased out, so I guess now they'll just use the Glad Wrap their lunch came wrapped in?
Yes, I'm well aware I'm talking about last mile copper phone / data connections, not undersea cables. I'll get my coat, it stops more water than your average plastic shopping bag.
These are pretty resistant to water, but the polyethylene does become porous over extended time periods
And, as the article (and my house[1]) shows - the problem is where the cables terminate.
[1] Exterior connection is on the pavement, in a water runoff area. The connection either wasn't sealed properly when installed ot (more likely) something went wrong afterwards. After about 3 years occupancy of the house, I started to get DSL drops and bad line noise every time it rained for any length of time. If the runoff got deep enough, it reached the line connection in the pavement and proptly filled it up. At which point, DSL became unusable as did the landline. BT (after many attempts and logging it as "no fault found" because of how long it took them to investigate) eventually fixed it. But only after I poured several watering-cans of water over the area to simulate the rainwater runoff..
at risk from rising sea levels.
Are they talking about real sea level rise or is this some pie in the sky idea they got from an unvalidated computer model?
In the real world there are some places where the sea level has risen a little mainly because the land has sunk, while there are other places where the sea level has dropped but in general terms there has been very little change in level over the past 100 years.
The only real problem would be if California has an earthquake and disappears into the sea, but that might be considered a good thing ;)
"It never takes long for articles like this to reveal those still in denial about climate change due to our greenhouse gas emissions. What evidence would ever convince you?"
Models that make verifiied predictions would help. I think that if you forget your preconceptions and do some research, you will find that the Climate Models have never made even one prediction that would persuade an objective, unbiased observer. It's not that CO2 isn't a greenhouse gas. It is. And it isn't that CO2 isn't increasing. The CO2 measurement program put in place by Charles Keeling in the 1950s stands up to scrutiny.
But the Global Climate Models are clearly generating highly dubious numbers and worse, they aren't providing insights into what causes glaciations, what ends them, what causes obvious cyclic phenomena like ENSO, PDO, AMO. It may be that the idea of climate modeling using the same basic techniques used for weather forecasting simply can't ever work over time spans greater than, at most, a few hundred hours.
@ Ivan 4
Sea level is a bit odd in UK, as situation quite complex. Quite a lot of UK land is still "rebounding" upwards, very gradually (we are talking geology and long time scales) from being compressed by heavy ice covering in the last ice age.
Thus depends how sea level rises (not just amount oif water but thermal expansion to consider)relative to land movements, and then you get things like erosion of land to factor in - most coastal land is in flux and land may be lost / gained in short time scales depending on the environment.
Then add in plate movements...
All gets very complex, modelling is thus difficult, but people give it a try to do as good a job as they can. Models are imperfect but a lot better than nothing.
There's also an interesting theory that a Danish friend of mine once pointed out. If all the ice melts and the sea rises, Denmark and similar areas will actually see the sea lower. A lot of the water will tend to bulge around the equator, leaving the polar regions with less water. She's expecting Denmark to get bigger as a result.
All very complex as you say.
"Quite a lot of UK land is still "rebounding" upwards, "
in some parts.
Other parts (such as the southeast) are rebounding the other way, having been beyond the glaciers and pushed upwards by the land squashed downwards by the glaciers.
The result is that the UK is far more geologically active than people realise and has a long history of large earthquakes (richter 6+) at intervals far enough apart that people forget they happen (the next Dover and Canterbury quake cycles are well "overdue")
Mind you that only needs to be a 200-300 year cycle - lookup "New Madrid" to see an even bigger disaster waiting to bite people on the arse. The USA has only woken up to that one in the last 25 years and is vastly unprepared for the consequences of a sequence of 8+ shocks in the middle of the continent (it will be far worse than anything Yellowstone or the Cascades can inflict on the population there)
"Are they talking about real sea level rise or is this some pie in the sky idea they got from an unvalidated computer model?"
It doesn't matter what your view is on this. I've tried to explain this before. Climates change over time. Sea levels change over time. Irrespective of whether you think this can be stopped by reducing CO2 emissions or whether you think it doesn't happen anyway you're going to be proved wrong. Even in places where there's a medium term* geological lowering of land level some ports have silted up and found themselves inland.
Don't expect your coastlines to remain in the same place. Don't expect floodplains not to be flooded. And don't expect fossil carbons to be an endless supply. Our descendants are going to curse us for shoving them up power-station chimneys when they run out of chemical feed-stocks (and that includes coke for making steel).
* Since the first few millennia of the current interstadial.
California has an earthquake and disappears into the sea, but that might be considered a good thing
Even better if there's an earthquake and the rest of the US disappears, leaving only California.. (and Canada of course - I'd recommend that Canada start deploying nukes along the border in order to snap the continent in half..)
That way, the 49ers might finally win a Superbowl again.
The science fiction of yesteryear has inspired much of what we enjoy today, so it is not without merit. Nevertheless, I have a difficult time considering any technology prognostication beyond 3-5 years as anything but science fiction. It is absolutely impossible to determine what the technical realities of the Internet will be in fifty years.
My theory is that in fifty years the backbone of the global network that replaces the Internet will consist largely of satellite constellations in LEO, and that dependence upon submarine cables will be significantly reduced. It isn't any more or less valid than what professors from UW theorize, or anyone else for that matter.
Frankly, the thought of taking seriously predictions that are unreliable beyond five years, which are further augmented by predictions that are unreliable beyond ten days, is hysterically funny.
"The Dutch solved these sorts of problems 300 years ago."
Up to a point. It comes with other kinds of problems - eg: 1953's "de Watersnoodramp"
The British solution is called the Thames barrier - and that is no longer suffficient to contain a 1953-level surge.
> Well , given that a "1953 level surge" must be a constant
A surge by definition happens against the day to day average level.
The Thames barrier was intended to only be used in anger a few times per decade and to last until at least 2032. It's being used a few times per year and has already come close to being overtopped on at least one occasion.
https://www.theguardian.com/cities/2015/feb/19/thames-barrier-how-safe-london-major-flood-at-risk
As the article points out, it's predicted that sun and moon positions are expected to result in higher tidal surges in the North Sea between 2032-2060 than have been seen in the 1960-2030 period.
Well, yes and no. The "watersnood ramp" was the result of a combination of factors. A lot of which have been tackled by the "delta plan". Flood defences aren't and will never be 100% fail safe but the Dutch system works pretty dang well. I also seem to recall the Brits where warned the Thames barrier was under-sized even in the design phase.
There is little problem planning a downtime to alter the shore installation given several years notice. Unplanned cuts get fixed all the time. The operator network have enough capacity to just works with what is left. On the multi decade time scale, you have maintain power plant. The only potential risk is that sea defense fails or coastal erosion catches you by surprise.
Impacted means compressed by an impact or blow. Apparently this is not the effect noted, so maybe "affected" would be a better choice.
The general term 'impact' has unfortunately become a universal and often highly imprecise replacement for a range of specific and precise words indicating effects. The result is loss of real meaning.
In a case such as this it matters, as the real effects appear to be corrosion-related and due to water permeability of the fibres, neither of which have anything at all to do with impacts.
Finally, an easily verifiable, objective measure of climate change. "1,100 Internet traffic hubs – data centres, Internet exchanges and the like – will be surrounded by water within 15 years." Not just some minor damage to some of them due to a tsunami, or a rogue wave, or random storm surge. 1,100 specific internet traffic hubs *surrounded by water* due to rising sea levels.
If that starts to happen within the next 5-10 years, with a vast majority of the *1,100 surrounded by water within 15 years*, then climate change/global warming is a thing and the skeptics will buy in. If not, then it's a hoax, and the Global Warming Alarmists will pipe down and we can move on with our lives. Right?
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