Small scales variability of the wet tropospheric correction

Marie-Laure Frery (CLS, France)

CoAuthors

Bruno Picard (Fluctus SAS, France); Francois Soulat (CLS, France); Nicolas Picot (CNES, France); Gérald Dibarboure (CNES, France); Nathalie Steunou (CNES, France)

Event: 2019 Ocean Surface Topography Science Team Meeting

Session: Instrument Processing: Propagation, Wind Speed and Sea State Bias

Presentation type: Type Poster

The wet tropospheric correction (WTC) is a major source of uncertainty in altimetry budget error, due to its large spatial and temporal variability. For most of the current and future nadir altimetry missions, a nadir microwave radiometer (MWR) provides brightness temperature (TB) observations from which the WTC is retrieved.

For the future SWOT mission, two radiometers will be aboard, respectively pointing at the center of each swath. The WTC over the whole swath will be estimated by linear interpolation between the two retrieved WTC.

The spatial and temporal variability of the WTC has been characterized by Stum et al in 2011 by analysis of MWR and model estimations. In this study, scanning radiometers were used in order to estimate the correlation radius in the zonal and meridional directions. The study was performed globally over ocean.

In the study presented here, two methods will be used to estimate the small scales variability of the wet tropospheric correction (below 20-30 km). Over ocean, we will use Jason-1 Geodetic phase/Jason2 matchups, comparing the WTC estimated for each mission as the distance between the two missions is varying. The method was initially developed by G. Dibarboure to estimate the SSH spatial variability in Karin/Swot_nadir comparisons.

Over land or coastal areas, using high density GPS networks, analyses of the differences between each couple of GPS stations provding Zenithal Tropospheric Correction will be analyzed with respect to the distance that separate them.
 

Poster show times:

Room Start Date End Date
The Gallery Tue, Oct 22 2019,16:15 Tue, Oct 22 2019,18:00
The Gallery Thu, Oct 24 2019,14:00 Thu, Oct 24 2019,15:45
Marie-Laure Frery
CLS
France
mdenneulin@groupcls.com