ODC PPSD Probabilistic Power Spectral Densities
The PPSD quality service illustrates noise levels at different frequencies for channels archived at ORFEUS Data Center. This application queries a database of hourly segmented power spectral densities. At the time a request is made, individual PSDs are aggregated to show probabilistic distributions of the seismic noise levels. PSDs are calculated by the method described by McNamara, 2004 using ObsPy.