Accession Number : ADP008730

Title :   Satellite Altimetry: Attempts to Progress Beyond Studies of the Statistics of Mesoscale Variability,

Corporate Author : OREGON STATE UNIV CORVALLIS COLL OF OCEANIC AND ATMOSPHERIC SCIENCES

Personal Author(s) : Chelton, Dudley B. ; Schlax, Michael G.

Report Date : NOV 1993

Pagination or Media Count : 47

Abstract : Because of uncertainties in the marine geoid and orbit height, most applications of altimetric data have focused on mapping the sea level variance statistic. These studies have been very successful at defining the geographical distribution of eddy variability and have highlighted the close relationship between transient eddies, the intensity of the mean flow and the bathymetry. Altimeter data have also been used to estimate surface geostropic velocities and map the variance of geostropic velocity (or, equivalently, the geostrophic Reynolds stresses). These studies have demonstrated the importance of the transport of horizontal momentum into the mean flow by transient eddies. Other obvious applications of altimeter data include mapping the time evolution of the sea level field for studies of wind and buoyancy forced ocean circulation and descriptive studies of mesoscale processes such as meandering and ring formation. Such applications are limited by a number of difficult technical challenges, mostly related to uncertainties about what space and time scales can be resolved by the complex space-time sampling characteristics of satellite data. A method is presented here for identifying aliasing patterns in an arbitrary sample design and for quantifying the resolution capability of the data set. Although the discussion emphasizes altimeter data, the method is applicable to any irregularly sampled data set. The maximum resolution capability of the GEOSAT orbit configuration (neglecting measurement errors and data dropouts) is found to be about 3 deg in latitude and longitude by 30 days.

Descriptors :   *MAPPING, *HEIGHT FINDING, *SEA LEVEL, STATISTICAL ANALYSIS, ANALYSIS OF VARIANCE, OCEANOGRAPHY, SATELLITE COMMUNICATIONS, ESTIMATES, RADIO ALTIMETERS.

Subject Categories : Cartography and Aerial Photography
      Physical and Dynamic Oceanography
      Geodesy

Distribution Statement : APPROVED FOR PUBLIC RELEASE