Severe storms during Earth history

Abstract

Although severe storms are recognized as important agents in sediment transport, many questions remain to demonstrate genetic links between specific sedimentary structures and textures and proposed generative agents. A detailed, physically based consideration of climatic and geographic controls on the generation and distribution of severe storms is presented on the basis of modern observations, physical processes deduced from these observations, and climate model experiments using past geographies. The results suggest that simple latitudinal distinctions for storm type (severe winter storm or hurricane) or inference from estimates of global warmth are not adequate to consider genetic links for storm-related deposits. Climate and geography produce substantial variability in storm-generation rates and in storm distributions. For example, geography may inhibit poleward penetration of hurricanes or enhance a broad latitudinal distribution. The record of tropical-sea surface temperatures indicates that values may have been below hurricane-generation thresholds during the Eocene and glacial stages. Land-sea distribution and associated thermal contrasts strongly influence the distribution and intensity of winter storms. The results from models can be compared favorably with observations of probable-storm sedimentation.