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5. For historical reasons, mapfiles generated by ESMF_RegridWeightGen using bilinear interpolation do not include complete output grid information. In particular, they lack gridcell area, probably because the presence of a diagnosed area could be misconstrued to imply a conservation property of the mapping which, by their nature, interpolative schemes lack. However, it is helpful to include area so long as users understand that interpolative maps are non-conservative. The new maps do thismapfiles include gridcell area for bilinear interpolation maps.
The new grids and mapfiles address these problems, which have always existed in ACME and its predecessors (CESM, CCSM, CCM)...