edu.ucar.opensky::articles:17343 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-26T16:24:08.088033 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7891757 Propagation delays induced in GPS signals by dry air, water vapor, hydrometeors, and other particulates 1999-04-27T00:00:00Z publication https://n2t.org/ark:/85065/d7891757 https://doi.org/10.1029/1999JD900095 Solheim, Frederick author Vivekanandan, Jothiram author Ware, Randolph H. author Rocken, Christian author UCAR/NCAR - Library publisher Dry air, water vapor, hydrometeors, and other particulates (sand, dust, aerosols, and volcanic ash) in the atmosphere introduce microwave propagation delays. These delays must be properly characterized to achieve the highest accuracy in surveying and atmospheric sensing using Global Positioning System (GPS) signals. In this paper we review the theory of microwave propagation delays induced by the above atmospheric constituents and estimate their maximum delays. Because the structure of atmospheric refractivity can be highly complex and difficult to model, and because measurement tools are unavailable for characterizing most of the refractive components, we use simplified examples to illustrate its effects. Our results show that propagation delays due to water vapor, cloud liquid, rain, and sandstorms can be significant in high-accuracy GPS applications. For instance, propagation through 1 km of heavy rain can induce 15-mm delays in L1₁ and because delays due to scattering are dispersive and alias as ionospheric delays in L₃ processing, L₃ range errors are magnified to 20 mm. Depending upon the distribution of precipitation relative to the configuration of GPS satellites, such unmodeled delays can induce horizontal and vertical errors of several centimeters. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication An edited version of this paper was published by AGU. Copyright 1999 American Geophysical Union. None eng geoscientificInformation