SCEC Award Number 21176 View PDF
Proposal Category Individual Proposal (Data Gathering and Products)
Proposal Title Robust Common-Mode Filtering to Best Reduce Uncertainty and Temporal Variability in CGM GPS Velocities
Investigator(s)
Name Organization
Corné Kreemer University of Nevada, Reno
Other Participants
SCEC Priorities 2a, 5c, 1a SCEC Groups Geodesy
Report Due Date 03/15/2022 Date Report Submitted 12/22/2023
Project Abstract
 We applied the CMC Imaging approach (Kreemer & Blewitt 2021) to the time-series of all CGPS stations in the western US available from the Nevada Geodetic Lab (NGL) (Blewitt et al. 2018). We consider the time interval Jan 1 1994 till Dec 31, 2021. CMC Imaging results in significantly reduced scatter in the GPS time-series, and correspondingly the velocity uncertainties as well. The actual velocities will improve as well, particularly for shorter operating stations, as long period signals such as droughts get captured by the common-mode and removed from the time-series.
Intellectual Merit The project showed the efficacy of CMC Imaging and how it can help improve community geodetic velocities and their uncertainties
Broader Impacts The project supported a first generation graduate student.
Exemplary Figure Figure 7 - Example time-series for station TORP of MIDAS velocity for 2.5 year periods centred on a moving window for every 0.2 years. Red/blue line and outline are velocity and one standard deviation for unfiltered and filtered time-series, respectively. Velocities are plotted relative to long-term trend and, for reference, the dashed and dotted lines are 1 and 2 standard deviations in that trend, resp. Scatter is indicated by the RMS statistic.