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The spectra above from single snaphots have a lot of noise which can be removed by averaging. We next analyze how much averaging is necessary from an aqua planet NE256 simulation with 1 month of daily snapshots. The legend indicates how many snapshots (spaced 1 day apart) were used when averaging E(k). With 28 snapshots the data is still a touch noisy at the lower frequencies, so we recommend at least 60 snapshots. Need to test the minimum spacing: 60 snapshots from hourly data is probably not as good as 60 snapshots from daily data. In the plot below, each curves are all shifted downward so they would not be plotted on top of each other.
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