Abstract
A correlation function varying in both time and space, ”Time-Space Correlation method”, was
applied to GEOSATaltimeter data collected from November 1986 to September 1989 (repeat
cycles 1- 62) in order to estimate wave propagation of theeddy field in the Kuroshio Extension
region. Analysis of 62 sets of collinear data has yielded the dominant speeds and directions of
wave propagations. In the zonaldirection, waves tend to propagate westward with speeds of 1.5
- 5.6 cms^-1 between 40°N and 30°N, which are in good agreement with the theoretical speeds. In
the meridional direction, the tendency of wave propagation in the eastern region of the study area
is different from that in the western region. In the eastern region, waves seem to propagate
northwardwith speeds of 2.0 - 3.0 cms^-1. However, we cannot determine whether these north
ward speeds are actual speeds or apparent speeds due to decrease of the zonal speeds with in
creasinglatitude. In contrast,propagations in the western regiontend to be towardthe axis of the
Kuroshio Extension, which is consistent with the Kuroshio Extension being an energy source.
