Data Services Products: MEQL - typhoon Maysak Microseism Energy Quick Look (MEQL) Highlight - super typhoon Maysak

Summary

Images on this page represent the median integrated power time series calculated from the power spectral densities (PSDs) for the vertical, N-S and E-W components of selected seismic stations along the path of super typhoon Maysak (formed on 2015-03-26 & dissipated on 2015-04-07).

Description

IRIS DMC’s Noise Toolkit is used to compute microseism energy (ME) variations at different period bands for selected GSN stations located along the super typhoon Maysak’s path. These ME values are calculated by integrating the power spectral density (PSD) functions computed from the waveform data of the above stations. The resulting power time histories show variations in stations noise level caused by passage of super typhoon Maysak.

Image to the right (click for a larger view) shows map of Maysak’s path and its wind speeds in blue (data from US Naval Research Laboratory, Marine Meteorology). On this map location of 4 selected seismic stations: IU.GUMO, IU.DAV, RM.SZP & TW.YULB are shown in red.

For each station median microseismic power values are computed for the (BHZ, BH1,BH2) or (BHZ BHN,BHE) channel groups at period bands of 1s to 5s, 5s to 10s & 11s to 30s that correspond to the local microseism (LM), secondary microseism (SM) and the primary microseism (PM) bands respectively. The resulting microseismic power values are smoothed using a moving 6 hour median window. The time span for computations is from 2015-03-20 to 2015-04-12 that covers typhoon Maysak (formed on 2015-03-26 & dissipated on 2015-04-07).

The following images (one set per station) show the microseism energy temporal variation of the BHZ and 2 horizontal channels at the selected stations for the period band of 1s to 5s (local microseism, top row), 5s to 10s (secondary microseism, middle row) and 11s to 30s (primary microseism, bottom row). click on each image for a larger view.

IU.GUMO

local microseism (LM), 1s to 5s
secondary microseism (SM), 5s to 10s
primary microseism (PM), 11s to 30s

IU.DAV (gaps in data)

local microseism (LM), 1s to 5s
secondary microseism (SM), 5s to 10s
primary microseism (PM), 11s to 30s

RM.SZP

local microseism (LM), 1s to 5s
secondary microseism (SM), 5s to 10s
primary microseism (PM), 11s to 30s

TW.YULB

local microseism (LM), 1s to 5s
secondary microseism (SM), 5s to 10s
primary microseism (PM), 11s to 30s

Citations and DOIs

Credits

  • IRIS DMC Products Team

Categories

Tags

MEQL

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