An objective interpolation method for spatiotemporal distribution of marine plankton

Abstract

A Lagrangian-Eulerian interpolation method for the objective analysis of marine plankton data was developed. Based on the Gauss-Markov theorem, this method takes into account the advection effect on the distribution of passive marine plankton, and yields an estimate and confidence at every interpolating point (x, y, z, t) which is optimal in the least squares error. This method was demonstrated in the analysis of plankton data collected in the California Current region during June 1993. The interpolated time series of spatial distributions of plankton revealed areas where plankton features were more permanent due to weak advection and areas where plankton features were more time-dependent due to the existence of strong currents. Results show north-south transports and exchanges of plankton populations produced by the complex flow system in the California Current region. This Lagrangian-Eulerian interpolation produces synoptic spatial distributions of plankton at given times and their error fields, and can be used as a basic analytical tool to understand advection effects in plankton distributions.