Toarcian greenhouse warming shifted climate belts poleward with global change implications

Atmospheric convection cells determine the latitudinal position of climate belts. Changes therein, because of anthropogenic forcing, will have a major impact on local–regional ecosystems. However, the magnitude of latitudinal change in the position of atmospheric convection cells, and by inference climate belts is poorly understood. Here, we analyze changes in the isotopic composition of land plant molecular fossils preserved in sedimentary archives spanning the Toarcian Oceanic Anoxic Event (~183 Ma), one of the largest climate change events in the last 500 million years, to reconstruct latitudinal changes in palaeo-humidity. Our data reveal a significant poleward expansion of the low-latitude arid climate belts to mid-palaeo-latitudes (~10°), in response to major carbon releasing, associated with global warming. This improves our understanding of environmental dynamics during periods of climate change.