title: Evidence for global cooling in the Late Cretaceous.
abstract: The Late Cretaceous 'greenhouse' world witnessed a transition from one of the warmest climates of the past 140 million years to cooler conditions, yet still without significant continental ice. Low-latitude sea surface temperature (SST) records are a vital piece of evidence required to unravel the cause of Late Cretaceous cooling, but high-quality data remain illusive. Here, using an organic geochemical palaeothermometer (TEX86), we present a record of SSTs for the Campanian-Maastrichtian interval (~83-66 Ma) from hemipelagic sediments deposited on the western North Atlantic shelf. Our record reveals that the North Atlantic at 35 °N was relatively warm in the earliest Campanian, with maximum SSTs of ~35 °C, but experienced significant cooling (~7 °C) after this to <~28 °C during the Maastrichtian. The overall stratigraphic trend is remarkably similar to records of high-latitude SSTs and bottom-water temperatures, suggesting that the cooling pattern was global rather than regional and, therefore, driven predominantly by declining atmospheric pCO2 levels.
authors.affiliation: Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK.
authors.forename: Christian
authors.initials: C
authors.lastname: Linnert
authors.affiliation: Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK.
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Robinson
authors.affiliation: Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK.
authors.forename: Jackie A
authors.initials: JA
authors.lastname: Lees
authors.affiliation: Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK.
authors.forename: Paul R
authors.initials: PR
authors.lastname: Bown
authors.affiliation: Departamento de Ciencias de la Tierra, Instituto de Investigación en Ciencias Ambientales (IUCA), Universidad de Zaragoza, Pedro Cerbuna, 12, E-50009 Zaragoza, Spain.
authors.forename: Irene
authors.initials: I
authors.lastname: Pérez-Rodríguez
authors.affiliation: Dipartimento di Scienze della Terra "A. Desio", Università degli Studi di Milano, via Mangiagalli 34, 20133 Milano, Italy.
authors.forename: Maria Rose
authors.initials: MR
authors.lastname: Petrizzo
authors.affiliation: Dipartimento di Scienze della Terra "A. Desio", Università degli Studi di Milano, via Mangiagalli 34, 20133 Milano, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Falzoni
authors.affiliation: Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK.
authors.forename: Kate
authors.initials: K
authors.lastname: Littler
authors.affiliation: Departamento de Ciencias de la Tierra, Instituto de Investigación en Ciencias Ambientales (IUCA), Universidad de Zaragoza, Pedro Cerbuna, 12, E-50009 Zaragoza, Spain.
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Arz
authors.affiliation: 1] Department of Geosciences, Mississippi State University, 108 Hilbun Hall, PO Box 5448, Oktibbeha, Mississippi 39762, USA [2].
authors.forename: Ernest E
authors.initials: EE
authors.lastname: Russell