The large-scale distribution of coal deposits is generally associated with wet paleoclimates and is given a wide tolerance for paleotemperatures. Numerical modeling of the climate pattern considering continental positioning at 100 Ma indicates five latitudinally controlled "wet" and "dry" zones. Coal deposits have a high probability of being formed in the wet zones where precipitation exceeds evaporation. The global belts of net precipitation and net evaporation for the Cretaceous show no basic latitudinal deviation from those of today. The wet zones run from the polar regions to approximately the 35° latitudes and include the equatorial region between the 4° to 8° latitudes. Based upon precipitation balance alone, coals would be expected in the equatorial ropics and the higher latitudes up to and including the polar regions.

Several factors, such as the absence of coal deposits from Cretaceous tropical landmasses, indicate that other controls on coal formation are present. As part of IGCP Project 191 (Cretaceous Paleoclimate Atlas Project), the significance of climate control on coal formation is determined by mapping coal distribution relative to paleogeography and coal abundance and quality. The quantity and quality of North American data relative to quantitative coal distribution provides a good framework for observation in the Cretaceous. Distributions of coal by Cretaceous stage level show a good relationship with paleolatitude and a shifting pattern relative to sea level cycles.

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