Share Email Print

Proceedings Paper

Inclusion of high resolution MODIS maps on a 3D tropospheric water vapor GPS tomography model
Author(s): Pedro Benevides; Joao Catalao; Giovanni Nico; Pedro M. A. Miranda
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Observing the water vapor distribution on the troposphere remains a challenge for the weather forecast. Radiosondes provide precise water vapor profiles of the troposphere, but lack geographical and temporal coverage, while satellite meteorological maps have good spatial resolution but even poorer temporal resolution. GPS has proved its capacity to measure the integrated water vapor in all weather conditions with high temporal sampling frequency. However these measurements lack a vertical water vapor discretization. Reconstruction of the slant path GPS observation to the satellite allows oblique water vapor measurements. Implementation of a 3D grid of voxels along the troposphere over an area where GPS stations are available enables the observation ray tracing. A relation between the water vapor density and the distanced traveled inside the voxels is established, defining GPS tomography. An inverse problem formulation is needed to obtain a water vapor solution. The combination of precipitable water vapor (PWV) maps obtained from MODIS satellite data with the GPS tomography is performed in this work. The MODIS PWV maps can have 1 or 5 km pixel resolution, being obtained 2 times per day in the same location at most. The inclusion of MODIS PWV maps provides an enhanced horizontal resolution for the tomographic solution and benefits the stability of the inversion problem. A 3D tomographic grid was adjusted over a regional area covering Lisbon, Portugal, where a GNSS network of 9 receivers is available. Radiosonde measurements in the area are used to evaluate the 3D water vapor tomography maps.

Paper Details

Date Published: 16 October 2015
PDF: 13 pages
Proc. SPIE 9640, Remote Sensing of Clouds and the Atmosphere XX, 96400R (16 October 2015); doi: 10.1117/12.2194857
Show Author Affiliations
Pedro Benevides, Univ. de Lisboa (Portugal)
Joao Catalao, Univ. de Lisboa (Portugal)
Giovanni Nico, Instituto per le Applicaziioni del Calcolo "Mauro Picone" (Italy)
Pedro M. A. Miranda, Univ. de Lisboa (Portugal)

Published in SPIE Proceedings Vol. 9640:
Remote Sensing of Clouds and the Atmosphere XX
Adolfo Comerón; Evgueni I. Kassianov; Klaus Schäfer, Editor(s)

© SPIE. Terms of Use
Back to Top