We exploit a very large global database of in situ current velocity, and temperature time series at fixed-positions (i.e. not drifting) to create summary statistics of ocean currents. Of principal interest are a decomposition of energy in different frequency bands, and the vertical and horizontal decorrelation length scales, and the interdependence between length scales and timescales. These in situ summary statistics will be complemented with those possible from satellite data (especially low-frequency motions of near surface currents, and their horizontal decorrelation scales.) To the extent possible, we will explore statistics of processes relevant to the mechanical energy budget of the ocean: 1) mechanical energy fluxes, especially the temporal correlation of vertical velocity and pressure believed to play an important role in the vertical transfer of kinetic energy to the abyss, 2) characterization of the bottom boundary layer and its role in dissipated mechanical energy. The summary statistics will include means for the World Ocean, different ocean basins, and estimates of statistical uncertainty and regional variability. For instance, we will estimate the cumulative distribution of fraction of total kinetic energy in the internal gravity wave frequency band, among many other summary statistics. By presenting the cumulative distribution one can find identify both the median and the variability about the median found in the World Ocean. The global summary statistics we explore are useful end products in themselves that are presently largely lacking in the oceanographic literature. They are also useful for many applications including planning new observational programmes such as satellite missions, validating ocean numerical modelling projects, and understanding physical processes and comparison with theoretical predictions. These applications are being pursued in collaboration with colleagues in the United States and Europe.
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