Haiti data to help quake prediction
doi:10.1038/nindia.2010.89 Published online 6 July 2010
Do sudden changes in surface and atmospheric parameters and ozone level signal an impending earthquake?
A team of Indian earth scientists strongly believes so. They have reached this conclusion after analyzing data during the recent earthquake in Haiti that killed thousands of people.
"The satellite and ground data show pronounced changes one day prior to the main Haiti earthquake event which occurred on 12 January 2010," Ramesh Singh, who led the research, told Nature India. Analysis of the data shows existence of a 'coupling' between lithosphere and atmosphere — a knowledge that could be exploited for predicting earthquakes, he says.
Singh who was formerly with IIT Kanpur is presently a professor of earth system science and remote sensing at Chapman University in California and is also an affiliate faculty at Sharda University in Noida near New Delhi. Singh carried out the study together with his colleague Waseem Mehdi and graduate student Manish Sharma, both at Sharda University.
Singh said the study was prompted by earlier observations by him and other groups that some marked changes take place in the ground, atmosphere and ionosphere before the occurrence of high magnitude earthquakes. He wanted to confirm if such changes also occurred during the Haiti earthquake.
To do this, Singh and his collaborators used data from ground observatories and US space agency NASA's remote sensing satellites. The surface and atmospheric parameters over the epicenter of the Haiti earthquake for a one year period were used for the analysis to see variations in these parameters before, during and after the earthquake.
According to their report, the surface temperature at a height of 2 meters above ground over the epicenter of Haiti earthquake reached the minimum one day prior to the main event. A low air temperature was also observed at different heights over the epicenter and relative humidity was observed to peak one day prior to the earthquake event.
The surface latent heat flux (which is the heat from the Earth's surface to the atmosphere) also peaked one day prior to the main event exactly as was found by Singh in the case of Gujarat (India) earthquake of 26 January 2001. The total ozone concentration dipped to minimum on the day of the Haiti earthquake on 12 January 2010 and afterwards found to increase — similar to the pattern seen during other earthquakes — Gujarat (India) in 2001, Denali (in Alaska) in November 2002, Sumatra in December 2004 and Wenchuan (China) earthquake of May 2008.
"The present results clearly show pronounced changes in surface, atmosphere and total ozone concentration, associated with the Haiti earthquake," the scientists report. Singh said that the Haiti study confirms the changes observed in other earthquakes but scientists are still debating about the physical processes responsible for the observed changes prior to the earthquakes.
In conclusion the scientists report that ground and atmosphere parameters "show a strong coupling which need to be observed continuously in earthquake prone areas to understand if the complementary nature will provide an indication of an impending earthquake."
- Singh, R. P. et.al. Complementary nature of surface and atmospheric parameters associated with Haiti earthquake of 12 January 2010. Nat. Hazards Earth Sys. 10, 1-7 (2010)