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Apply temporal filter

Year-on-year differences

This option replaces each data point with the dfference between the
value of this year and the previous year. It acts as a (primitive)
high-pass filter and is often used to eliminate to first order slow
variations or trends. Note that higher-order effects, such as a
slowly varying variance, are not removed.
Subtract mean of previous years

This is an extension of the year-on-year differences in which the mean
of the previous Average with previous years

The converse is to average with No overlap

If there is an option "no overlap" (currently only on the verification pages), this means that instead of the default sliding window, non-overlapping windows are taken. An example: if you have 100 years of data with a 10-yr running window ("average with [9] previous years"), you will normally get 90 or more data points that are not independent: years 1-10, 2-11, 3-12, ..., 91-100. With this option you will get 10 independent data points: years 1-10, 11-20, ..., 91-100.

Plans

One day I will implement more sophisticated low-pass, high-pass and
band-pass filters.
See also the detrend option.

This page is part of the help system of the KNMI Climate Explorer