Tonga volcano eruption

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The Big Bang that took a nation off the grid

The strong submarine Hunga-Tonga-Hunga-Ha'apai volcano eruption and the subsequent tsunami and shock waves were felt across the Pacific Ocean and beyond.

This “Big Bang” released mechanical energy equivalent to hundreds of Hiroshima nuclear explosions, creating supersonic air pressure waves that were observed from space.

In the Kingdom of Tonga, the volcanic ash, tsunami and shock waves caused widespread devastation in several islands, and, in particular, destroyed the only fibre-optic cable that connects the islands with the rest of the world, leaving the country offline for more than three weeks. Four months later, communication between islands is still not fully restored. Disruption of Internet connectivity with Tonga had serious implications on its economy: about 30 per cent of household consumption and 40 per cent of national GDP in Tonga depend on remittances from international migrants sent via the Internet. The disruption particularly affected women, who are highly dependent on remittances and have to deal with the increases in water and food prices during the emergency.

Like Tonga, many other islands rely on a single cable, increasing their vulnerability not just to volcanic eruptions or tsunamis but also to more frequent disturbances, such as damage from fishing boats.

Additionally, the relief and recovery efforts of the Tongan government and emergency services were hampered by the inability to communicate. Access to satellite connectivity is limited, and even with it, communications failed due to the volcanic ash. Undersea fibre optic cables are crucial for the communication of the Pacific Islands with the rest of the world.

Like Tonga, many other islands rely on a single cable, increasing their vulnerability not just to volcanic eruptions or tsunamis but also to more frequent disturbances, such as damage from fishing boats. While adding an additional cable seems an easy solution, countries face many challenges, starting with the high financial investment needed (e.g. the construction of the cable to Tonga cost $15 million in 2013) but also concerns related to foreign surveillance and ownership of data by the countries providing more cables.

Wider picture

In a world highly interconnected by communication and technology, the inability to “be online” becomes a vulnerability in the context of extreme events as the case of the Hunga-Tonga Hunga-Ha'apai volcano eruption showed. Many Pacific Island countries, such as Vanuatu and Samoa, also depend on a single submarine cable, and satellite services are restricted and not widespread enough to cover basic connectivity needs. Damage to critical telecommunication infrastructure not only hinders response actions but also minimizes the effectiveness of early warning systems, compromising disaster risk management strategies and triggering offline scenarios as in Tonga.

Root Causes

Unequal distribution of economic opportunities and limited livelihood options

A lack of perception, awareness or preparation in governance relating to risk management and response

Pursuit of economic or developmental interests with a lack of consideration for impacts on the environment

Drivers

An absent or poorly communicated warning of a hazard’s impending arrival.

Intentional mass removal of trees, often for resource extraction or changing land use.

Infrastructure vulnerable to extreme events, often due to lack of investment, maintenance, inadequate planning or poor construction.

Impacts

Through their impacts on natural and agricultural systems, supply chains and economies, the impacts of tipping points and disasters can put access to the foods we depend on for survival at risk

Water security can be impacted by tipped systems and disasters when sufficient availability or access to water for health and livelihoods is disrupted. Water sources can also get contaminated and make vectors for other risks

Tipping point impacts and disasters can force people to move from their homes due to the loss of shelter, livelihoods or the risk of further incidents occurring. People may be temporarily displaced or urged to migrate to other areas

Disasters cause fatalities both when they occur and in the aftermath with cascading effects on physical and mental health

Public and private structures and systems can be affected by disasters and risk tipping points impacts, from homes and properties to physical assets critical for providing health services, transport, food, water, communications and more

Even those surviving disasters or tipping point impacts when they occur can be at risk of short- and long-term health impacts cascading from pollution, damage of critical infrastructure, livelihood disruption or other consequences of systems being affected

Just like people, nature also feels the impacts of systems tipping and various hazards resulting in threats to health and physical damage to individuals, populations, communities or entire ecosystems

Reduction of people’s ability to support themselves or their family, both temporarily or permanently, is an impact that is interconnected with many others, including health and food security

Solutions

Coexisting with natural processes for our overall benefit

Having established safety nets to protect people from adverse impacts

Developing risk-aware infrastructure and land-use planning

Enhancing our capacity to predict and communicate risks

Explore more from the 2023 report