Namun, sejatinya alam sudah memberi peringatan. Apakah itu? Menurut profesor ilmu bumi di Chapman University di California, Dimitar Ouzounov, atmosfer di atas episentrum gempa Jepang mengalami perubahan tak biasa -- dalam beberapa hari menjelang bencana.
Penelitian ini masih data awal, belum dipublikasikan di jurnal akademis dan direview oleh ilmuwan lain, namun menawarkan sesuatu yang menarik, bahwa mungkin gempa bisa diprediksi. "Meski, potensi ilmuwan memperkirakan terjadinya gempa masih 'jauh'," kata Ouzounov seperti dimuat LiveScience, Kamis 19 Mei 2011.
Menatap langit untuk melihat pertanda bencana, khususnya gempa, sebenarnya bukan ide baru. Ada teori yang dikenal sebagai "Lithosphere-Atmosphere-Ionosphere Coupling mechanism" atau "Mekanisme kaitan Litosfer-Atmosfer-Ionosfer".
Seperti ini penjelasannya: sebelum gempa bumi terjadi, patahan yang tertekan akan mengeluarkan lebih banyak gas, khususnya gas radon yang tidak berwarna dan tak berbau.
Setelah berada di ionosfer, gas radon melepaskan molekul udara elektronnya, memisahkan partikel bermuatan negatif (elektron bebas) dan partikel bermuatan positif. Partikel-partikel bermuatan yang juga disebut ion, lantas menarik air dalam proses melepaskan panas. Dan, para ilmuwan bisa mendeteksi panas ini dalam bentuk radiasi inframerah.
Menggunakan data satelit, Ouzounov dan para koleganya mengawasi perubahan atmosfer yang terjadi beberapa hari sebelum gempa Jepang. Mereka menemukan, konsentrasi elektron dalam ionosfer meningkat, demikian juga dengan radiasi inframerah. Pada 8 Maret 2011, tiga hari sebelum gempa, adalah saat yang paling anomali.
Para peneliti juga telah mengumpulkan data lebih dari 100 gempa di Asia dan Taiwan. Menurut Ouzounov, mereka menemukan korelasi yang sama untuk gempa yang magnitudenya lebih besar dari 5,5 skala Richter dengan kedalaman kurang dari 50 kilometer. Tim saat ini sedang berusaha melibatkan para ahli gempa Jepang dan seluruh dunia dalam sebuah misi ambisius: pemantauan atmosfer internasional sebagai upaya mitigasi gempa.
Meski demikian, kesuksesan ramalan gempa masih belum terjamin. Belum ada satu pun orang yang memprediksi gempa berdasar data atmosfer. Terkadang pertanda gempa bisa dilihat dari tingkah aneh binatang atau air tanah yang berubah aliran.
Apakah ada peluang gempa bisa diprediksi lewat data atmosfer? "Ini sangat menarik," kata Henry Pollack, profesor emeritus geofisika di University of Michigan, yang tak terlibat dalam penelitian ini. "Namun masih sulit untuk disebut sebagai sebuah terobosan."
Menruut Pollack, peneliti harus melihat banyak data atmosfer terkait gempa yang ada untuk memastikan fenomena menyangkut pecahnya patahan gempa. Juga harus ditelaah, seberapa sering anomali muncul, namun tak terkait sama sekali dengan gempa.
Sementara, Terry Tullis, profesor emeritus ilmu geologi di Brown University juga sama ragunya. Para ilmuwan ahli gempa telah banyak belajar di masa lalu, untuk tidak merasa senang setiap kali muncul metode prediksi gempa. "Saya tak bermaksud menyingkirkan optimisme itu, tapi dalam titik ini, orang harus skeptis."
Friday afternoon, March 11, 2011, a massive earthquake with a strength of 8.8 on the Richter scale rocked Japan. Earthquake triggered a tsunami that rolled up buildings, people, whatever that is in the northeast coastal region. Japan, which is famous as the country most prepared to deal with earthquake disasters, helter skelter.
However, his true nature has been given a warning. What is it? According to professor of earth sciences at Chapman University in California, Dimitar Ouzounov, the atmosphere above the epicenter of Japan experienced unusual changes - within a few days before the disaster.
This research is still preliminary data, not yet published in academic journals and reviewed by other scientists, but offers something interesting, that might be an earthquake can be predicted. "However, scientists estimate the earthquake potential is still 'far'," said Ouzounov like loaded LiveScience, Thursday, May 19, 2011.
Staring at the sky to see the omen of disaster, particularly earthquakes, is actually not a new idea. There is a theory known as "Lithosphere-Atmosphere-ionosphere coupling mechanism" or "connection mechanism lithosphere-ionosphere-atmosphere."
Such an explanation: before the earthquake occurred, a depressed fracture will expend more gas, especially radon gas is colorless and odorless. Once in the ionosphere, radon gas releases electrons air molecules, separating the negatively charged particles (free electrons) and positively charged particles. Charged particles are also called ions, and then draw the water in the process releases heat.And, scientists can detect this heat in the form of infrared radiation.
Using satellite data, Ouzounov and his colleagues watched the atmosphere change that occurred several days before the Japanese earthquake. They found that increasing the concentration of electrons in the ionosphere, as well as infrared radiation. On March 8, 2011, three days before the quake, is the most anomalous.
Researchers also have collected data on more than 100 earthquakes in Asia and Taiwan. According Ouzounov, they found a correlation similar to the earthquake that magnitudenya greater than 5.5 on the Richter scale with a depth of less than 50 kilometers. The team is currently trying to involve experts Japanese earthquake and the whole world in an ambitious mission: monitoring international atmosphere as earthquake mitigation efforts.
However, the success of earthquake prediction is still not guaranteed. Not a single person who predict earthquakes based on atmospheric data. Sometimes a sign of an earthquake can be seen from the strange behavior of animals or changing groundwater flow.
Is there any chance of an earthquake can be predicted by the data's atmosphere? "It's very exciting," said Henry Pollack, professor emeritus of geophysics at the University of Michigan, who was not involved in this research. "It is still difficult to be called as a breakthrough."
Menruut Pollack, researchers have seen a lot of earthquake-related atmospheric data to ensure that there are phenomena related to earthquake fault rupture. It should also be reviewed, how often anomalies appear, but not related at all with the quake.
Meanwhile, Terry Tullis, a professor emeritus of geological sciences at Brown University as well as ragunya. Scientists seismologists have learned a lot in the past, to not feel happy every time appears earthquake prediction method. "I do not mean to get rid of that optimism, but in this point, people should be skeptical."
source:vivanews.com