Those parameters and p-values are likely wildly off. But the main point is: it is very hard to envisage any dataset which would make the past three months usual.
I even deliberately chose a simulated dataset which had 9 cable cuts / 5 years, i.e. above average.
Baltic is very shallow, which raises the probability of anchor drags. More telling would be: the Baltic area compared to global ocean surface with less than 400m depth — 400m being roughly the max anchor chain length in commercial shipping. Still, I would suspect significant deviation.
An even better picture would be possible based on complete data. To my knowledge, the only commercially available comprehensive dataset on faults is OceanIQ‘s Cable Fault Data https://oceaniq.co.uk/services/cable-fault-data/
There are several estimates that need better numbers, that being one. One should also account for depths.
Another one. How many of those 15.8% are anchors dragged from a ship mile after mile like our incidents? Likely a very small proportion. ”Dragging” as normally understood is not this.
Dragging refers to a ship anchoring and as natural forces increase they lose grip and do damage. Or, the anchor bu mistake on something. These are stationary ships.
Id bet such represent close to every incident in those 15.8%. But have sofar not found good base for that. Safe to say, it is not all
Looking at the HELCOM database of shipping accidents in the Baltic Sea, the database contains only a single mention of an anchor damaging a cable in the last 20 years or so. Data is incomplete and likely missing stats as it's based on national reporting so caveats apply
In any case, whichever way you count it, the recent events constitute a significant statistical anomaly. Therefore "200 accidents occur yearly, it's within the norm" is completely misleading and the medias/services pushing that message either have their own agenda or limited mental faculties.
Furthermore, a ship just plowing through multiple cables, dragging her anchor for 10's or 100's of kilometers without noticing anything is exceedingly rare. Usual anchor drag cases mostly involve bad weather & rough sea state, which is not the case with these except new new polar bear.
This study into anchor drag incidents by Rawson and Brito touches on this subject, and one of their results was that "...larger drag distances are significantly less likely than shorter drag distances". I'm not data analysis-savvy enough to judge but looks legit
Statistical improbability does not equal attribution to RUS sabotage. Changed pattern of ship traffic (Shadow fleet) certainly would increase the probability of accidents even without nefarious intent. However the "Anchor drags happen globally all the time" argument is completely braindead.
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A completely off the cuff, take with huge pinch of salt*, estimate gives very low probability of cutting so many cables by chance.
* I fed cable cuts into my biodiversity code, so underwater cables are now basically Ugandan wasps.
- 30000 ships per month passing by cables
- 1.5 cable cuts per year
.. then simulated random data for five "normal" years matching those parameters.
The last three-month period is wildly unusual.
No real difference between months. (But remember, this part of the data is simulated data so shouldn't be.)
I even deliberately chose a simulated dataset which had 9 cable cuts / 5 years, i.e. above average.
Reduction to ACMA only may also lead to better results.
Another one. How many of those 15.8% are anchors dragged from a ship mile after mile like our incidents? Likely a very small proportion. ”Dragging” as normally understood is not this.
Id bet such represent close to every incident in those 15.8%. But have sofar not found good base for that. Safe to say, it is not all
Looking at the HELCOM database of shipping accidents in the Baltic Sea, the database contains only a single mention of an anchor damaging a cable in the last 20 years or so. Data is incomplete and likely missing stats as it's based on national reporting so caveats apply
This study into anchor drag incidents by Rawson and Brito touches on this subject, and one of their results was that "...larger drag distances are significantly less likely than shorter drag distances". I'm not data analysis-savvy enough to judge but looks legit