There are several causes for cut undersea cables, including:
1. Natural disasters: Undersea cables can be damaged by natural disasters such as earthquakes, tsunamis, and undersea landslides. The movement of tectonic plates or the shifting of underwater sediments can result in the cables being severed.
2. Ships and anchoring: Ships, particularly large cargo vessels or fishing boats, can accidentally anchor or drag their anchors across undersea cables, causing them to be cut. This can happen in busy shipping lanes or areas where fishing is common.
3. Fishing activities: Fishing trawlers or nets can also accidentally snag and damage undersea cables. In areas where fishing is prevalent, there is a higher risk of cables being cut due to these activities.
4. Sabotage or intentional damage: In some cases, undersea cables have been deliberately cut as an act of sabotage or terrorism. These incidents can disrupt communication networks and cause significant economic and social impact.
5. Aging and wear and tear: Over time, undersea cables can deteriorate due to factors such as corrosion or damage caused by severe weather conditions. This can result in the cables eventually breaking or being cut.
6. Maintenance activities: Undersea cables require regular maintenance, including repair and replacement. During these operations, there is a risk of accidental cutting or damage to the cables.
It is worth noting that undersea cables are generally designed to be durable and are protected by layers of armor and insulation to withstand various external factors. However, the causes mentioned above can still lead to cable cuts, which may require expensive and time-consuming repairs.
Citations:
[1] https://www.kentik.com/blog/dual-subsea-cable-cuts-disrupt-african-internet/
[2] https://www.wired.com/story/submarine-internet-cables-egypt/
[3] https://www.wired.com/story/russia-undersea-internet-cables/
[4] https://alaskapublic.org/2023/06/12/cut-cable-causes-weeks-long-north-slope-northwest-alaska-internet-and-cellphone-outages/
[5] https://www.lawfaremedia.org/article/cutting-cord-legal-regime-protecting-undersea-cables