In Pakistan, it is often reported that the internet is experiencing slowdowns, and one frequent explanation from Pakistan Telecommunication is that faults in the underwater internet cables are responsible for the disruptions. But how exactly do these underwater cables get damaged? Speculation abounds, with the most intriguing theory suggesting that shark bites might be to blame, leading to our internet service being interrupted.

The Importance of Undersea Cables

A staggering 99% of global digital communications rely on a vast network of underwater cables. If these cables break, it can cause widespread disruption in internet services. In this report, we aim to explore how the ocean's behavior impacts internet connectivity, whether sharks truly play a role in damaging these cables, and how technicians go about repairing them once they are damaged. We also delve into how technicians identify the locations and types of faults in these cables.

A Historical Context: The 1929 Earthquake

To understand the challenges of maintaining undersea cables, we can look back to November 18, 1929, when a significant earthquake measuring 7.2 on the Richter scale struck south of the Burin Peninsula in Canada. While the local residents experienced minimal damage primarily the shattering of some dishes—the underwater consequences were far more severe. A tsunami reaching a height of 43 feet struck the Burin Peninsula, resulting in 28 fatalities.

The earthquake triggered a landslide on the ocean floor, which went largely unnoticed by the public at the time, as there was little awareness of tsunami risks or the possibility of underwater landslides. When earthquakes or geological movements occur, the tectonic plates on the ocean floor shift, causing the water to become denser and increasing pressure on the seabed. This leads to landslides in the ocean, known as turbidity currents.

The 1928 earthquake generated a landslide that traveled several thousand kilometers, reaching speeds of 57 to 80 miles per hour. Although the event was not immediately recognized as significant, it served as a crucial lesson for the future. The path of the landslide coincided with the routes of the then-cutting-edge communication technology: the transatlantic cables. The earthquake caused these cables to break at 28 locations, with 12 of them snapping simultaneously while the remaining 16 broke at intervals.

The mystery lay in the timing: why did the cables not all break at once? Scientists later discovered in 1952 that the distance from the earthquake's epicenter determined when each cable would snap. The further a cable was from the earthquake's center, the longer it took to break. Researchers found that the landslide had exerted a powerful shock on the cables, which could withstand only a certain level of pressure before breaking.

At that time, little was known about turbidity currents. However, the damage to the cables, combined with the records of their failure, provided new insights into wave movements in the ocean’s surface and depths. Despite the complexity of repairing the cables back then, the event unveiled a previously unseen aspect of nature’s power.

As the decades passed and the network of underwater cables expanded, the repair and maintenance of these cables led to further scientific discoveries, alongside advancements in internet speed. Today, internet speed is so rapid that our daily lives, income, health, and safety increasingly depend on it, placing our existence at the mercy of these underwater cables.

The Impact of Cable Breaks on Internet Systems

So, why do our systems get thrown into disarray when these cables break? Currently, a total of approximately 1.4 million kilometers of cables stretch across the world’s oceans and seas. These cables are integral to every ocean and sea. If one cable is connected to another, their combined length would span as far as the diameter of the Sun. The task of transporting 99% of our information from one point to another relies solely on these cables.

Some might assume that these cables are thick and heavy, but surprisingly, most of them are only about two centimeters wide. Some cables are even as narrow as household pipes used for watering plants. If a widespread failure of internet cables were to occur, similar to the situation in 1929, communications between North America and Europe would be severely affected. However, according to Mike Clear, a researcher affiliated with the International Cable Protection Committee, "the network around the world has become quite robust."

The Frequency of Underwater Cable Incidents

Every year, between 150 and 200 incidents occur that damage these cables. However, compared to the sheer number of cables, the frequency of these issues is relatively low. Most problems encountered with these cables are resolved quickly. The world relies heavily on these underwater infrastructures, and as technology progresses, so does our ability to repair and maintain them effectively.

In conclusion, while the undersea internet cables play a crucial role in our digital communication, they are also susceptible to various natural phenomena and even animal interactions. As our dependence on the internet grows, understanding the intricacies of these cables and their maintenance becomes increasingly important. The next time you experience a slow internet connection, you might consider the complex world beneath the waves that supports our digital lives, along with the unseen challenges technicians face to keep us connected.