  A topological computation method, called the MGSTD method, is applied to
time-series data obtained from meteorological measurement. The method gives
decomposition of the dynamics into invariant sets and gradient-like transitions
between them, by dividing the phase space into grids and representing the
time-series as a combinatorial multi-valued map over the grids. Since the
time-series is highly stochastic, the multi-valued map is statistically
determined by taking preferable transitions between the grids into account. The
time-series data are principal components of pressure pattern in troposphere
and stratosphere in the northern hemisphere. The application yields some
particular transitions between invariant sets, which leads to circular motion
on the phase space spanned by the principal components. The Morse sets and the
circular motion are consistent with the characteristic pressure patterns and
the change between them that have been shown in preceding meteorological
studies.
