georefid:2002-030917SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=2002-030917<gco:CharacterString>Jiggling the tropical thermostat in the Cretaceous hothouse</gco:CharacterString>2002-01-01publicationgeorefid:2002-030917Norris, Richard D.Woods Hole Oceanographic Institution, Department of Geology and Geophysics, Woods Hole, MA, United StatesauthorBice, Karen L.Arizona State University, United StatesauthorMagno, Elizabeth A.Southampton Oceanography Centre, United KingdomauthorWilson, Paul A.authorGeological Society of America (GSA), Boulder, CO, United StatespublisherdocumentHardcopyGeology (Boulder)30 (4)299-302Modern open-ocean sea-surface temperatures rarely exceed approximately 28-29 degrees C, and the same has been thought to represent a rough maximum for past tropical climates. However, new isotopic estimates from the uppermost Cenomanian in the tropical western North Atlantic suggest that mixed-layer temperatures reached approximately 33-34 degrees C (+ or -2 degrees C) during the middle Cretaceous hothouse. Uppermost Cenomanian tropical sea-surface temperatures may have been as much as 4-7 degrees C warmer than the highest modern mean annual temperatures. Such extreme conditions suggest that warm tropical oceans could have driven substantially intensified atmospheric heat transport near the Cenomanian-Turonian boundary. The tropical "thermostat" was set higher than today, challenging the hypothesis of tropical climate stability.completedStratigraphyassemblagesAtlantic Oceanbiochemistryclimate changecoresCretaceousDeep Sea Drilling ProjectDemerara RiseDSDP Site 144Equatorial AtlanticForaminiferageochemistryGlobigerinaceaGlobigerinelloidesHedbergellaHeterohelixInvertebrataisotope ratiosisotopesLeg 14marine environmentMesozoicmicrofossilsNorth AtlanticNorthwest AtlanticO-18/O-16oxygenpaleoclimatologypaleoecologypaleotemperatureplanktonic taxaProtistaRotaliinasea-surface temperaturestable isotopestropical environmenturn:org.iodp:exp:14urnlargerWorkCitationcampaignurn:org.iodp:exp:14:site:144urnlargerWorkCitationstudyurn:org.iodp:exp:14urnlargerWorkCitationcampaignEnglishgeoscientificInformation-54.2031-54.20319.27149.2714