Steps in Compositing Analysis
q Select the basis for compositing and define the categories
     The categories might be related to the phase of some cyclic
phenomenon or forcing, or to time or distance from some event. For
example, we can use NINO3 index as the basis for compositing the
ENSO cycle.
q Compute the means and statistics for each category
      We calculate the mean SST, wind stress, or heat flux for the onset,
growing, and mature phases of the ENSO cycle.
q Organize and display the results
q Validate the results
      Validation of the results can be achieved in many ways. Statistical
significance tests are only one of these.