Boxing Day tsunami a reminder we are all in harm’s way

Twenty years ago today, the rising and falling floor of the Indian Ocean sent tsunamis pouring over highly vulnerable coastal communities across southern Asia, causing massive human suffering and sparking compassion and generosity as the world quickly realised the multinational impact of the tidal waves.

The death toll for Indonesia’s Aceh province is generally listed at about 160,000. The official global figure of those killed in the tsunami, including in Sri Lanka, India, Thailand and the Maldives among others, is upwards of 230,000 – 26 Australians among them.

Just as Australians had come running to the aid of victims 30 years earlier in the aftermath of Cyclone Tracy, the 2004 Boxing Day tsunami, brought out the best in the world; when confronted with our collective vulnerability, differences were cast aside.

A RAAF Hercules evacuates refugees from Banda Aceh after the tsunami.Credit: Nick Moir

Then-prime minister John Howard announced a $1 billion relief package for Aceh and the affected island of Nias. Australians donated millions as hastily organised aid concerts and an international cricket game rattled the tins. The tsunami also helped cement Australia’s emerging friendship with Indonesia – a relationship pivotal to stability and prosperity in our region. The calamity also shifted the political ground in Indonesia’s long-standing conflict with the separatist Free Aceh Movement, putting an end to the three decades of conflict. The arrival of aid prompted early hopes for a similar breakthrough in Sri Lanka’s long-running civil war with the Tamil Tigers, but it was to continue for five years.

The havoc and tragedy unleashed by the Boxing Day tsunamis set alarm bells ringing. When the tidal waves struck, there was no warning system. However, one positive and lasting outcome was the establishment two years later of an Indian Ocean tsunami warning system.

But for all we have learnt about these ferocious natural phenomena of the oceans, why is it we cannot better protect ourselves from their devastation?

The most common cause of tsunamis is an earthquake unleashed by sudden shifts in tectonic plates. Such violent forces are notoriously difficult to predict above water, let alone at ocean depths. And tsunamis move so fast that it is improbable much can be done to clear coastal areas in their paths.

In 1491, the Mahuika comet dropped into the Pacific Ocean, triggering a tsunami so forceful it crashed over the 100-metre high cliff at The Gap at Watsons Bay and obliterated much of the scientific record of any earlier tsunamis that had hit eastern Australia. Knowledge of Sydney’s vulnerability to such an event is therefore limited. But a 2018 analysis by the University of Newcastle found Manly’s Corso is the most vulnerable place in Sydney to a tsunami and put the likelihood of a tsunami powerful enough to flood Manly occurring in our lifetime at 12 per cent.

It is clear, however, none of us are out of harm’s way and the 20th anniversary of the Boxing Day tsunami is a reminder of another element in the risk of existence.

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