how to use gcm-filter to bandpass filter ？

[Blissful-Jasper]

1、How to use gcm-filter to bandpass filter in three-dimensional data? such as ： wind speed component：u、v 2、Whether to make the consideration of equal spacing. 3、How to set those parameters？ 4、 how to simply understand the data variables corresponding to the parameters

[NoraLoose]

Hi @xpji!

Re 1:

• Number of dimensions: GCM-Filters can be applied to three- (or four-) dimensional data, see for example here. But the filter operates over two dimensions only, which have to specified when applying the filter: filter.apply(da_masked, dims=['y', 'x'])
• Band-pass filtering: GCM-Filters is for low-pass filtering. If you want to create a band-pass filter, you can do this by using and combining GCM-Filters with different filter scales, see for example Equation (7) in @jakesteinberg's paper Steinberg et al., 2022.

Re 2 - 4: Here you can find examples for how to apply filters with equal filter scales in x- and y-direction.

Please let us know if you have further questions!

[NoraLoose]

I'm closing this issue because it has been stalled for more than a year.