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Analysis of tide gauge records from the December 2004 Indian Ocean tsunami
Author(s) -
Leonard Mark
Publication year - 2006
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2006gl026552
Subject(s) - tide gauge , geology , aliasing , sampling interval , sampling (signal processing) , seismology , indian ocean , interval data , oceanography , sea level , filter (signal processing) , statistics , mathematics , computer science , computer vision , data envelopment analysis
I analyze records of the tsunami caused by the 2004 Sumatra – Andaman M9.3 earthquake from tide gauges, seismic stations and satellites, in the central Indian Ocean. I demonstrate that the tide gauge records with sampling intervals of 4 minutes or more are seriously aliased and under‐sample the tsunami waveform. Care needs to be taken when using this data for modeling this or future tsunami. The 1 minute sampling interval data accurately record the main features of the tsunami. The tsunami had significant energy at periods shorter than 1 minute and this resulted in, probably minor, aliasing of the 1 minute data. It is suggested that tide gauges intended for monitoring of tsunami use a sampling interval of at most 60 seconds, with effective anti aliasing filters being applied. Where the data is to be used for modeling at least 4 samples per minute data should be recorded.