title: Intensification of the meridional temperature gradient in the Great Barrier Reef following the Last Glacial Maximum.
abstract: Tropical south-western Pacific temperatures are of vital importance to the Great Barrier Reef (GBR), but the role of sea surface temperatures (SSTs) in the growth of the GBR since the Last Glacial Maximum remains largely unknown. Here we present records of Sr/Ca and δ(18)O for Last Glacial Maximum and deglacial corals that show a considerably steeper meridional SST gradient than the present day in the central GBR. We find a 1-2 °C larger temperature decrease between 17° and 20°S about 20,000 to 13,000 years ago. The result is best explained by the northward expansion of cooler subtropical waters due to a weakening of the South Pacific gyre and East Australian Current. Our findings indicate that the GBR experienced substantial meridional temperature change during the last deglaciation, and serve to explain anomalous deglacial drying of northeastern Australia. Overall, the GBR developed through significant SST change and may be more resilient than previously thought.
authors.affiliation: MARUM-Center for Marine Environmental Sciences, University of Bremen, 28359 Bremen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Felis
authors.affiliation: Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory 0200, Australia.
authors.forename: Helen V
authors.initials: HV
authors.lastname: McGregor
authors.affiliation: Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, USA.
authors.forename: Braddock K
authors.initials: BK
authors.lastname: Linsley
authors.affiliation: School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK.
authors.forename: Alexander W
authors.initials: AW
authors.lastname: Tudhope
authors.affiliation: Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory 0200, Australia.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Gagan
authors.affiliation: Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8567, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Suzuki
authors.affiliation: Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa 277-8564, Japan.
authors.forename: Mayuri
authors.initials: M
authors.lastname: Inoue
authors.affiliation: 1] School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK [2] Department of Earth Sciences, University of Oxford, Oxford OX1 3AN, UK.
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Thomas
authors.affiliation: 1] Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory 0200, Australia [2] Australian Nuclear Science and Technology Organisation, Institute for Environmental Research, Kirrawee DC, New South Wales 2232, Australia [3] Department of Nuclear Physics, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, Australian Capital Territory 0200, Australia.
authors.forename: Tezer M
authors.initials: TM
authors.lastname: Esat
authors.affiliation: Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA.
authors.forename: William G
authors.initials: WG
authors.lastname: Thompson
authors.affiliation: National Centre for Antarctic & Ocean Research, Vasco-da-Gama, Goa 403804, India.
authors.forename: Manish
authors.initials: M
authors.lastname: Tiwari
authors.affiliation: Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, California 95064, USA.
authors.forename: Donald C
authors.initials: DC
authors.lastname: Potts
authors.affiliation: 1] Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), 27570 Bremerhaven, Germany [2] Climate Risk Analysis, Heckenbeck, 37581 Bad Gandersheim, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Mudelsee
authors.affiliation: Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa 277-8564, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Yokoyama
authors.affiliation: Geocoastal Research Group, School of Geosciences, The University of Sydney, Sydney, New South Wales 2006, Australia.
authors.forename: Jody M
authors.initials: JM
authors.lastname: Webster