1 Introduction
 1.1 Methodology of international modeling campaigns
 1.2 Community approaches to models and data
 1.3 Rationale for a grid standard
 1.4 Overview of paper
2 Grid terminology for Earth System science
 2.1 Geometry
 2.2 Vertical coordinate
 2.3 Horizontal coordinates
 2.4 Time coordinate
 2.5 Discretization
 2.6 Staggering, refinement, and the supergrid
  2.6.1 Triangular supergrids
  2.6.2 Raster grids
 2.7 Mosaics
 2.8 Boundary contact regions
 2.9 Overlap contact regions: Exchange grids and masks
  2.9.1 Masks
3 Representing the grid vocabulary in the CF conventions
 3.1 Linkages between files
 3.2 Grid mosaic
 3.3 Grid tile
 3.4 Unstructured grid tile
 3.5 Contact regions
 3.6 Variables
4 Examples
 4.1 Cartesian geometry
 4.2 Gaussian grid
 4.3 Reduced gaussian grid
 4.4 Tripolar grid
 4.5 Unstructured triangular grid
5 Gridspec implementations
 5.1 The GENIE Gridspec
 5.2 The GFDL implementation
6 Summary