Progress and challenges of the Dynamic Atmospheric Correction for altimetry over last 25 years

Loren Carrere (CLS, France)

CoAuthors

Damien Allain (CLS, LEGOS, FRANCE); Florent Lyard (LEGOS, FRANCE); Yannice Faugère (CLS, FRANCE); Romain Baghi (CLS, FRANCE); Jean-Michel Lachiver (CNES, FRANCE)

Event: 2018 Ocean Surface Topography Science Team Meeting

Session: Tides, internal tides and high-frequency processes

Presentation type: Type Oral

Given its current accuracy and maturity, altimetry is considered a fully operational observing system dedicated to various applications such as operational oceanography and climate studies. Altimeter measurements are corrected for several geophysical effects in order to isolate the oceanic variability, and the Dynamic Atmospheric Correction (DAC) is the second most important one after the tide correction. This DAC correction allows for the removal of high frequency ocean variability induced by the atmospheric forcing and aliased by the altimetric measurements.

The accuracy of the DAC has been improved over the last 25 years leading to centimetric accuracy in open ocean. However significant errors still remain mainly in shallow waters and in polar regions, due to bathymetric errors, to atmospheric forcing errors, to local lack of resolution, or to sea ice effects ...
The DAC has recently evolved for the three delivery modes corresponding to Near Real Time (NRT) products, Short Time Critical (STC) and Non Time Critical (NTC) and these improvements directly benefit to all altimetry product, including recent missions such as Jason-3 and Sentinel-3 as well as the past time series.

We propose to give an overview of the evolution of the DAC model over last 25 years of altimetry; we will also present the new ways of improvements which are currently being tested and we will introduce the new challenges of this DAC correction for the coming high-resolution altimetry.
 

Oral presentation show times:

Room Start Date End Date
Lagoa Do Congro Fri, Sep 28 2018,11:39 Fri, Sep 28 2018,11:51
Loren Carrere
CLS
France
lcarrere@cls.fr