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BDSN Noise Summary

One of the tools used by the BSL to monitor the health of the network is the analysis of the power spectral density of the background noise. Once a week, the power spectral density (psd) is computed in the period ranges 16-32, 32-64, 64-128, 128-256, and 256-512 seconds is computed for all the broadband stations. This weekly assessment is reviewed by the BSL staff and is available on the Web.

For comparision, here are three cumulative summary plots for the vertical, north, and east components in the band from 32-128 seconds. These figures display time series of the PSD results for the current calendar year. In order to show all the stations on the same plot, the mean has been removed from each time series and is displayed on the right-hand side. The offset between the stations is 20 dB.

Cumulative PSD results
Year Vertical North East
2011 PSD plot PSD plot PSD plot
2010 PSD plot PSD plot PSD plot
2009 PSD plot PSD plot PSD plot
2008 PSD plot PSD plot PSD plot
2007 PSD plot PSD plot PSD plot
2006 PSD plot PSD plot PSD plot
2005 PSD plot PSD plot PSD plot
2004 PSD plot PSD plot PSD plot
2003 PSD plot PSD plot PSD plot
2002 PSD plot PSD plot PSD plot
2001 PSD plot PSD plot PSD plot
2000 PSD plot PSD plot PSD plot
1999 PSD plot PSD plot PSD plot

In the table below, we provide cumulative psd plots for each station, summarizing the results for the year to date. In each figure, the vertical component psd is plotted with blue diamonds, the north component psd with red squares, and the east component psd with green circles. The results are presented in the 5 different frequency bands, and the USGS/Albuquerque low noise model is plotted as a dashed line in each.

In all figures, the PSD units are in dB (decibel) relative to 1 (m/s**2)**2/Hz. These plots are updated weekly.

Station Name Cumulative PSD
ARC 1999 2000 2001 None
BDM 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
BKS 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
BRIB 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
BRK 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
CMB 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
CVS 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
FARB 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
HOPS 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
HUMO None 2003 2004 2005 2006 2007 2008 2009 2010 2011
JCC None 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
JRSC 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
KCC 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
MHC 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
MIN 1999 None
MNRC None 2003 2004 2005 2006 2007 2008 2009 2010 2011
MOD None 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
ORV 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
PACP None 2003 2004 2005 2006 2007 2008 2009 2010 2011
PKD 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
POTR 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
SAO 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
WDC 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
WENL 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
YBH 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

The PSD results were computed using an algorithm developed by BSL staff seismologist Bob Uhrhammer. The software used compute the power spectral density is available to the public.

BDSN Overview BDSN Map BDSN Table