Global Seawater Oxygen-18 Database

Gridded Data

Simple Surface Interpolation

The data are on the standard GISS 4°x5° grid with half-size polar boxes, the point (1,1) is the South Pole (88-90°S), the point (1,2) covers 180-175°W, 88-84°S, etc. up to the North Pole box (88-90°N) at (72,46). All points at the first latitude (South pole: J=1) and the last latitude (North Pole: J=46) are homogenous.

The ASCII data can be read into a FORTRAN program using

      REAL DATA(72,46)
      CHARACTER TITLE*80
      READ(*,'(80A)') TITLE
      READ(*,'(8F9.3)') DATA

The skip value is -999.000 and denotes that no data were found within 5° of the center of that grid point.

Fully Gridded Data

This dataset is described in LeGrande and Schmidt (2006) and is available on the 33 Levitus climatology levels of the ocean and at 1°x°1 resolution. Each level is a separate record in the binary file. The data are available here in two binary formats:

A new version (1.1) is now available. Updates are described here.

Original version (1.0) is still available:

The "plain" binary version of the dataset, "calculated_d18O.data", can be read in using big-endian standards and the following FORTRAN code:

      REAL*4 DATA(360,180,33)
      CHARACTER TITLE*80
      ...
      OPEN(1,FILE="DATA",FORM="UNFORMATTED")
      DO L=1,33   ! LOOP OVER LEVELS
         READ(1) TITLE, DATA(:,:,L)
      END DO

The first box is at the south pole, centered at 179.5°W. The skip value is -1e30.

Reference

LeGrande, A.N., and G.A. Schmidt 2006. Global gridded data set of the oxygen isotopic composition in seawater. Geophys. Res. Lett. 33, L12604, doi:10.1029/2006GL026011.

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