  The present study was undertaken with the aim of contributing to the
characterization of the nonstationary variability of the hydrological regime of
the Kasai River using the wavelet analysis for 1940-1999. The rainfalls and
discharge over Kasai Basin have marked fluctuations with a perceptible downward
trend and some shift around 1950, 1960, 1970, 1983 and 1994. The results show
that rainfalls over Kasai basin and the discharge at Ilebo station patterns
exhibit a strong annual oscillation and some intermittent oscillations in 2-8
years (1950-1975, 1983-1995) and 8-16 years (1970-1999) time scales. The
wavelet coherence analysis reveals a weak possible connection between
hydrological variables (rainfalls, discharge) and climate indices relative to
sea surface temperature and atmospheric circulation over Atlantic tropical,
Indian and Pacific Oceans (coherence less than 0.55).
