Search Results

You are looking at 11 - 12 of 12 items for :

  • Author or Editor: P. Y. Le Traon x
  • Refine by Access: All Content x
Clear All Modify Search
M.-I. Pujol
,
G. Dibarboure
,
P.-Y. Le Traon
, and
P. Klein

Abstract

An Ocean System Simulation Experiment is used to quantify the observing capability of the Surface Water and Ocean Topography (SWOT) mission and its contribution to higher-quality reconstructed sea level anomaly (SLA) fields using optimal interpolation. The paper focuses on the potential of SWOT for mesoscale observation (wavelengths larger than 100 km and time periods larger than 10 days) and its ability to replace or complement altimetry for classical mesoscale applications. For mesoscale variability, the wide swath from SWOT provides an unprecedented sampling capability. SWOT alone would enable the regional surface signal reconstruction as precisely as a four-altimeter constellation would, in regions where temporal sampling is optimum. For some specifics latitudes, where swath sampling is degraded, SWOT capabilities are reduced and show performances equivalent to the historical two-altimeter constellation. In this case, merging SWOT with the two-altimeter constellation stabilizes the global sampling and fully compensates the swath time sampling limitations. Benefits of SWOT measurement are more important within the swath. It would allow a precise local reconstruction of mesoscale structures. Errors of surface signal reconstruction within the swath represent less than 1% (SLA) to 5% (geostrophic velocities reconstruction) of the signal variance in a pessimistic roll error reduction. The errors are slightly reduced by merging swath measurements with the conventional nadir measurements.

Full access
J. A. Johannessen
,
P.-Y. Le Traon
,
I. Robinson
,
K. Nittis
,
M. J. Bell
,
N. Pinardi
, and
P. Bahurel

In response to the joint European Commission and European Space Agency initiative to establish by 2008 a system for Global Monitoring for Environment and Security (GMES), the Marine Environment and Security for the European Area (MERSEA) Strand-1 Project was executed to assess and demonstrate the capacity of present monitoring and forecasting systems. The study area covered the North Atlantic, with its northwest European shelf seas, and the Mediterranean. By integrating of existing satellite observations with data from in situ measurement networks and ocean models, daily mean products and forecasts from four core data assimilation systems (~1 0 km resolution) were compared and distributed through an Open-source Project for a Network Data Access Protoco (OPeNDAP) server from1 June 2003 to 31 May 2004.Moreover, downscaling to high-resolution (1–5 km) models was used for specific applications to harmful algal bloom, eutrophication, and oil spill monitoring in the Baltic, North Sea, Irish Sea, Iberian coastal shelf seas, and the Aegean Sea. The lessons learned from this project are reported here.

Full access