  The comparative analysis of output from multiple models, and against
observational data analysis archives, has become a key methodology in reducing
uncertainty in climate projections, and in improving forecast skill of medium-
and long-term forecasts. There is considerable momentum toward simplifying such
analyses by applying comprehensive community-standard metadata to observational
and model output data archives.
  The representation of gridded data is a critical element in describing the
contents of model output. We seek here to propose a standard for describing the
grids on which such data are discretized. The standard is drafted specifically
for inclusion within the Climate and Forecasting (CF) metadata conventions.
  The contents of this paper have been in the "grey literature" since 2007: it
has been posted to arXiv to be citable. To preserve its integrity, the contents
have not been updated.
