This research investigated the potential of the upper atmosphere layer height changes as precursor of the Padang
Earthquake on 30 September 2009. We analyzed the occurrence of atmospheric gravity wave (AGW) in all-sky imager
(ASI) images and h’F in ionosonde mounted on Kototabang (0.2°S, 100.3°E, -10.4° magnetic latitude) Indonesia from
seven days before and after the earthquake and found that there was an unusual evening in h’F variation on 24 and 29
September 2009. A positive h’F deviation on 24 and 29 September 2009 are with a maximum value of 42 and 31.5. For
both these dates, the maximum h’F value reached 234 km and 261 km at 00:30 LT and 20:30 LT with the median value
of 192 km and 229.5 km, respectively. The increase in h’F on 24 September 2009 before the midnight was caused by
encouragement from AGW observed at a wavelength of OH bands (~86 km) that happened a few minutes earlier. While
the increase in h’F on 29 September 2009, suspected to be caused by the emergence of the AGW, though it cannot be
proven because ASI does not operate due to rainy weather over Kototabang. For Dst index during the month of
September 2009, there is nothing worth under -50 nT, this means a change of altitude h’F six and one days before the
earthquake is not caused by the influence of magnetic storm but caused by AGW resulting from the epicenter.
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