Monitoring of Land Subsidence in Louisiana from GNSS Observations

GULFNet is a continuously operated network established by Louisiana Spatial Reference Center (LRSC) which is jointly created by the Louisiana State University (LSU), Center for GeInformatics (C4G) and the National Geodetic Survey (NGS). GULFNet is a positional infrastructure network that is fundamental for surveying work, GIS mapping, geospatial applications, precision farming, and navigation. The GULFNet consists of 120 stations and it is primarily located in Louisiana and the Gulf Coast from Texas at the border of Mexico to Fernandina Beach in the east coast of Florida. The GULFNet continuously operated reference stations (CORS) are aiming at determining and localizing the land subsidence in Louisiana and the Gulf Coast with high-precision using time-series analysis. In this study, we select a number of GULFNet stations to estimate the land subsidence rate in Louisiana from 2013 to 2018 as a part of GULFNet processing. The archived raw data have been mutually processed with JPL (Jet Propulsion Laboratory) data by means of precise point positioning (PPP) using Gipsy-X software. The results and estimate velocities are presented.