Effectiveness of Tsunami Early Warning Unclear

The tsunami that hit Java earlier this week was detected by the new tsunami early warning system. According to Nature, the 'tsunami warning was issued ... just 4 minutes after a quake measuring 7.2 on the Richter scale occurred several hundred kilometres south of Jakarta, Indonesia.' Specifically, 'a 7-centimetre sea-level rise' was detected 'indicating that the quake had generated a tsunami.' This data was then relayed to Jakarta from the Pacific Tsunami Warning Center in Japan, as it was detected. What remains unclear, though, is whether or not the Jakarta officials 'were able to convey the information to the local population' as the '2-metre-high wave ... arrived at the coast only 15 to 20 minutes after the earthquake.' Peter Koltermann, a UNESCO official, stated 'it was a successful first test, but it is too early to say exactly how successful.'