Without warningThe disasters this week show people on Pacific shores still lack basic protection from tsunamis
Richard Hamblyn guardian.co.uk, Friday 2 October 2009 20.00 BST
The official responses to this week's double disaster – first, the Samoan tsunami on Tuesday, and then the Sumatran earthquakes on Wednesday and Thursday – again reveal worrying flaws in the early warning systems that are the first, and usually only, lines of defence against the natural hazards that regularly afflict the world's most seismically unstable regions.
When Tuesday's 8.3 magnitude undersea earthquake struck at 6.48am local time, 190km south of the Samoan islands, it was registered instantly at the Pacific Tsunami Warning Centre on Ewa Beach, Oahu, which then issued tsunami warnings to a number of Pacific island groups, including New Zealand and Samoa.
Once such warnings are received, it is up to local authorities to pass them on to their coastal inhabitants by whatever methods have been agreed, with instant automated text messaging among the most widely used techniques. Text messaging is of particular value in the event of locally generated tsunamis, when the window of warning is usually a matter of minutes, rather than hours. But those Samoans who felt Tuesday's tremor and waited for the text that would tell them whether to head inland waited in vain, for no message was sent out.
And had anyone turned down the radio or television so as not to miss the incoming text alert, they would have missed the islands' only warning – given out on local radio just as the first of two giant waves began battering the islands' southern shores.
On New Zealand's North Island, meanwhile, several hundred people received their "instant" text alert some three hours late, by which time the tsunami warning had already been cancelled. The messaging service has now been suspended, and an inquiry is already under way.
But technological failure is not the only factor that contributed to Tuesday's death toll, which currently stands at 169: according to officials at the Samoa Meteorology Division, many of those killed were caught by the morning's second wave as they headed to the beaches to pick up the fish that had been washed ashore by the first wave. Given that tsunamis usually take the form of a series of powerful waves, sometimes even hours apart, such a fatal lack of awareness speaks of a wider failure to pass on even basic tsunami knowledge and preparedness to the islands' coastal inhabitants.
Education remains the only truly effective means of reversing the effects of disaster amnesia, but the last island-wide safety drill took place in October 2007, in response to a tsunami earlier that year that killed 22 people on the nearby Solomon Islands. Ironically, a similar tsunami safety drill had been scheduled for American Samoa on Tuesday, but the real thing arrived unannounced instead.
The situation in Indonesia is just as bad. Although neither of this week's Sumatran earthquakes proved tsunami–genic, the authorities have to work on the assumption that any powerful undersea earthquake is liable to generate tsunamis (the epicentre of Wednesday's 7.6 magnitude quake was around 50km offshore from the city of Padang). This is, after all, the same faultline that caused 2004's Boxing Day disaster, and produces regular local tsunamis every year.
But there are only 22 detection buoys to monitor all 6,000 inhabited islands in the Indonesian archipelago, and none of those cover northern Sumatra, Indonesia's most vulnerable region and the scene of the highest loss of life in 2004, where the death toll in Aceh province alone exceeded 130,000. And even where there is detection equipment in place, there are no guarantees it will stay there. In July 2006 a local tsunami off the Javanese coast killed nearly 700 people; it later transpired that the two detection buoys that monitor that stretch of coast had been removed from the sea some months before, and were awaiting repairs in a dockside warehouse. Given that these buoys cost about $250,000 each, and require at least $125,000 worth of annual maintenance per unit, tsunami preparedness is proving a costly undertaking for developing nations such as Indonesia.
This week's earthquakes were severe enough – the official death toll is 715, though UN estimates put it closer to 1,100 – but had either been tsunamigenic, the city of Padang would have been as unprotected as it was in December 2004, despite the $30m that has been spent in developing the region's interim warning system. Sumatra will have to wait until 2010 for its own detection buoys to be installed, but as Tuesday's pantomime across the far wealthier south Pacific demonstrated, installing the equipment is one thing; getting it to do its job is quite another.
Richard Hamblyn guardian.co.uk, Friday 2 October 2009 20.00 BST
The official responses to this week's double disaster – first, the Samoan tsunami on Tuesday, and then the Sumatran earthquakes on Wednesday and Thursday – again reveal worrying flaws in the early warning systems that are the first, and usually only, lines of defence against the natural hazards that regularly afflict the world's most seismically unstable regions.
When Tuesday's 8.3 magnitude undersea earthquake struck at 6.48am local time, 190km south of the Samoan islands, it was registered instantly at the Pacific Tsunami Warning Centre on Ewa Beach, Oahu, which then issued tsunami warnings to a number of Pacific island groups, including New Zealand and Samoa.
Once such warnings are received, it is up to local authorities to pass them on to their coastal inhabitants by whatever methods have been agreed, with instant automated text messaging among the most widely used techniques. Text messaging is of particular value in the event of locally generated tsunamis, when the window of warning is usually a matter of minutes, rather than hours. But those Samoans who felt Tuesday's tremor and waited for the text that would tell them whether to head inland waited in vain, for no message was sent out.
And had anyone turned down the radio or television so as not to miss the incoming text alert, they would have missed the islands' only warning – given out on local radio just as the first of two giant waves began battering the islands' southern shores.
On New Zealand's North Island, meanwhile, several hundred people received their "instant" text alert some three hours late, by which time the tsunami warning had already been cancelled. The messaging service has now been suspended, and an inquiry is already under way.
But technological failure is not the only factor that contributed to Tuesday's death toll, which currently stands at 169: according to officials at the Samoa Meteorology Division, many of those killed were caught by the morning's second wave as they headed to the beaches to pick up the fish that had been washed ashore by the first wave. Given that tsunamis usually take the form of a series of powerful waves, sometimes even hours apart, such a fatal lack of awareness speaks of a wider failure to pass on even basic tsunami knowledge and preparedness to the islands' coastal inhabitants.
Education remains the only truly effective means of reversing the effects of disaster amnesia, but the last island-wide safety drill took place in October 2007, in response to a tsunami earlier that year that killed 22 people on the nearby Solomon Islands. Ironically, a similar tsunami safety drill had been scheduled for American Samoa on Tuesday, but the real thing arrived unannounced instead.
The situation in Indonesia is just as bad. Although neither of this week's Sumatran earthquakes proved tsunami–genic, the authorities have to work on the assumption that any powerful undersea earthquake is liable to generate tsunamis (the epicentre of Wednesday's 7.6 magnitude quake was around 50km offshore from the city of Padang). This is, after all, the same faultline that caused 2004's Boxing Day disaster, and produces regular local tsunamis every year.
But there are only 22 detection buoys to monitor all 6,000 inhabited islands in the Indonesian archipelago, and none of those cover northern Sumatra, Indonesia's most vulnerable region and the scene of the highest loss of life in 2004, where the death toll in Aceh province alone exceeded 130,000. And even where there is detection equipment in place, there are no guarantees it will stay there. In July 2006 a local tsunami off the Javanese coast killed nearly 700 people; it later transpired that the two detection buoys that monitor that stretch of coast had been removed from the sea some months before, and were awaiting repairs in a dockside warehouse. Given that these buoys cost about $250,000 each, and require at least $125,000 worth of annual maintenance per unit, tsunami preparedness is proving a costly undertaking for developing nations such as Indonesia.
This week's earthquakes were severe enough – the official death toll is 715, though UN estimates put it closer to 1,100 – but had either been tsunamigenic, the city of Padang would have been as unprotected as it was in December 2004, despite the $30m that has been spent in developing the region's interim warning system. Sumatra will have to wait until 2010 for its own detection buoys to be installed, but as Tuesday's pantomime across the far wealthier south Pacific demonstrated, installing the equipment is one thing; getting it to do its job is quite another.
posted by rjb @ Friday, October 02, 2009
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