and Again it happened during the Christmas season and, again, without warning, for the people: flood waves on Saturday at 21.30 local time in the Islands of Java and Sumatra coasts met in the Sundastraße, around 430 Indonesians and Indonesians in at the death torn to 1,500 were injured, many are still missing. Four years after the tsunami disaster of 2004, some 230,000 people were killed, was a German involvement in the developed early warning system at the Start. Why not hit it? We discussed with Jörn lauterjung from GeoForschungsZentrum Potsdam (GFZ). He has co-developed the technology.
TIME ONLINE: Indonesia’s early warning system alert as soon as an earthquake or tsunami is recorded, the dangerous flood waves, Tsunamis, therefore, trigger should hit. There is enough time left until the troubled sea, and water meets Land, people can still bring in security. So the idea. But last Saturday they were surprised by the deadly waves. The technique was broken?
Jörn Lauterjung is the Director for data, information and IT services at the GeoForschungsZentrum Potsdam (GFZ) and Co-Director of the Central Asian Institute for applied Geosciences. He was involved as a project coordinator in the development of the Indonesian tsunami early warning system. © private
Jörn Lauterjung: no, that was not an early warning system is broken. But this time, a landslide triggered by underwater after a volcanic eruption, the flood waves. And on such a special cause, the System is not designed. It fails in the case of strong classical earth – or seaquakes, which can reach at least a Magnitude of 7.0. 90 percent of all Tsunami events worldwide and in Indonesia. The cause this time was tragic, a concatenation of a volcanic eruption, an underwater landslide, and various other factors. There was no warning. This makes me very concerned. And also, that around Christmas people due to a Tsunami were killed.
Zeit ONLINE: But there was, despite everything, a vibration that stirred the sea water. The measuring stations are not conscious of?
according to Jung But. The early warning system has also recorded quite data of the Event. It registered a seismic activity of 5.1 – only the triggered no tsunami alert. On the basis of the measurement data, the computer – based System is not able to distinguish a vibration from a landslide or a volcanic eruption of an earth-or seaquake.
1/14 Two days later: villagers in Sumur the debris left by the Tsunami, to inspect. © Fauzy Chaniago/AP/dpa 2/14 eruption of Anak Krakatau, The volcano is under the water surface in the Sunda Strait between Sumatra and Java. © Nurul Hidayat/Bisnis Indonesia/Antara photo/Reuters 3/14 the destruction looks in Carita (province of Banten) from the air. © Akbar Nugroho Gumay/Antara Foto/Reuters 4/14 rescue workers search in Carita to the Victims. © Fauzy Chaniago/AP/dpa 5/14 In Carita breaks down a man, after he has identified a loved one among the dead. © Fauzy Chaniago/AP/dpa 6/14 The water washing is also a coach. © Azwar Ipank/AFP/ 7/14 police officers search for Victims in a destroyed beach hotel in Pandelang. © Jorge Silva/Reuters 8/14 injured on the loading area of a Transporter in front of a hospital in Pandeglang © Basarnas/Antara Foto/Reuters 9/14 residents inspect the damage of the tsunami at the coast in the South of Sumatra. © Ferdi Awed/AFP/ 10/14 Destroyed buildings and cars in Anyer, in the province of Serang © Dasril Roszandi/AFP/ 11/14 could be A Survivor in the rubble of their house in Sumur, from the mountains a few belongings, © Fauzy Chaniago/AP/dpa 12/14 In security: the inhabitants of the Region of Bandar rest in a government building. © Ardiansyah/Antara Foto/Reuters 13/14 A Bus with bright headlights in front of a Bungalow © Ed Wray/ 14/14 search in the rubble: a Survivor with a head-lamp in Tanjung © Achmad Ibrahim/AP/dpa
TIME ONLINE: Between the excitation of the tsunami under the water and the impact of the first flood waves on the coast and took just 24 minutes. Exactly where the waves were and how high they were?
according to Jung: The Tsunami was measured in the entire Sundastraße, that is, along the Strait between Sumatra and Java. The four of us level measurements are available, a total of between 30 and 90 centimeters. It will be of some coastal wave heights of 2.5 sections, but up to 3 meters reported, which can be generated by local reinforcement factors, such as the special topography of the seabed or of a particular coastal forms. In addition, the moon, and a particularly high Tide was full.
Zeit ONLINE: But you could program the early warning system so that it is factoring in all these factors, and also detects when a Tsunami of a landslide is triggered?
according to Jung: This is, unfortunately, extremely difficult and requires a considerable amount of instrumentation. It is also of no help, set early-warning system “more sensitive”, that is, the threshold for seismic events, for earthquakes of Magnitude 4 to 5 happen almost every day in Indonesia. This measure would then lead to a very large number of false alarms.
Indonesia – the number of dead after the Tsunami The Tsunami has risen to the Indonesian Islands of Sumatra and Java has killed at least 429 people. Among the dead were mostly local tourists. © Photo: Jorge Silva/Reuters
TIME ONLINE: In previous Tsunamis, there was also often a natural warning signs: sea water on the beaches pulled back far before the huge flood rolled on, the animals fled minutes before the impact of the water. People noticed this time because nothing?
according to Jung: no, that was particularly tricky at this event. It is none of the usual natural warning signs – not even a strong earthquake that could be felt over a certain period of time.
TIME ONLINE: The tsunami events with deadly consequences seem to pile up lately. Especially in Indonesia. This is only a subjective impression or are there statistics? And could the climate change have a reinforcing effect – for example, through rising sea levels?
according to Jung: This is probably a subjective impression, also through a larger Medieninteresse of such events is increased since the tsunami disaster of 2004. We must not forget that it is here again (just like in Sulawesi a few weeks ago) to a local Tsunami. And now no small-talk of the catastrophic event, but it has happened before in 2004 with a comparable frequency, only it wasn’t reported. The actual cause of all these phenomena is plate tectonics. Indonesia lies on a very active plate tectonic Zone. This has nothing to do with rising sea levels or other consequences of climate change.