Isotopic and palynological evidence for a new Early Jurassic environmental perturbation

► A negative carbon isotope excursion is noted in the Late Sinemurian. ► This CIE occurs in both the marine and terrestrial realms. ► The event coincides with the acmes of two thermophilic palynomorphs. ► These geochemical and palynological data indicate a warming event. ► It represents a release of isotopically light carbon.