Six cruises conducted during the U. S. GLOBEC, NW Atlantic program in January, March and June 1998 and 1999 provide the basis for this study. Surveys covered 1,500 kilometers of nearly replicate trackline around Georges Bank in about 10 days. Using wavelet analysis, power-law
distributions are determined to exist in horizontal alongtrack records of temperature, salinity, fluorescence, and acoustic backscatter, resolving spatial scales from 10^s of meters to 10^s of kilometers. These distributions are fractal, with distinct characters in different
seasonal and hydrographic regimes.

Self-similar (fractal) methods have been developed for characterizing the distribution of variance within a data series, and applying both the variability and the heterogeneity of the observed subset to extend observations into longer series. These methods make use of the fractal dimension determined from the observations. Variability in the data is preserved, because the fractal dimension is used to stochastically determine multiple solutions for new points. Heterogeneity in the data is also preserved, as fractal dimension describes variability over a continuum of scales. Many natural populations exhibit a fractal distribution that remains constant over a discrete range of scales, resulting in a power-law distribution. A critical scale is indicated when a given power-law distribution ends. Such a break is often followed by a rapid transition to a new power-law distribution.

Slopes of the determined power-law distributions (beta) are used to constrain a random midpoint displacement algorithm developed by Voss (1985) in the construction of two dimensional concentration fields. These fields are stochastic iterations of fractal fields characterized by the same fractal dimension as the observed transects. Fractally interpolated 2-D fields of fluorescence and acoustic backscatter serve as proxies, representing abundance and distribution of plankton populations on the Southern Flank of Georges Bank. Each field, based on three 100 kilometer 1-D transects, demonstrates the intermittency in plankton populations on
Georges Bank. Quantifiable intermittency in plankton populations exists over the entire range of resolved scales from meters to kilometers. Fractal interpolation has direct application to improving large-scale models of biologically mediated fluxes.

kef10@cornell.edu