Dimension Averaging

The Dimension Averaging operation can perform one of two average types:

1) spatial area average, weighted by cosine latitude; or

2) the mathematical mean (average) along one or more dimensions (without weighting). Averaging is done for all user selected geophysical parameters or data arrays contained in a set of input files representing a time series. The dimension-averaged data are then constructed into a time series and saved to a single output HDF file for further operations.

Inputs

The input to this operation is a set of input HDF files representing a time series. The input files contain the user selected parameters as n-dimensional data arrays.

Outputs

The output is an HDF file containing the dimension-averaged data as a time series.

Algorithm

Each dimension is averaged separately, except for area average where all values are averaged within the spatial region. Missing data points are filled with fill values during processing and are not included in the calculation. All other valid data points are averaged using the mathematical mean, which can be an weighted area average using the cosine latitude as the weight.

Mean value computation:

Weighted mean value computation (w is the weighting factor, in this case the cosine latitude):

This Technical Summary page is a draft version -- for information on this operation while

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