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The Last Interglacial (LIG) represents an invaluable case study to investigate the response of components of the Earth system to global warming. However, the scarcity of absolute age constraints in most archives leads to extensive use of various stratigraphic alignments to different reference chronologies. This feature sets limitations to the accuracy of the stratigraphic assignment of the climatic sequence of events across the globe during the LIG. Here, we review the strengths and limitations of the methods that are commonly used to date or develop chronologies in various climatic archives for the time span (~140-100 ka) encompassing the penultimate deglaciation, the LIG and the glacial inception. Climatic hypotheses underlying record alignment strategies and the interpretation of tracers are explicitly described. Quantitative estimates of the associated absolute and relative age uncertainties are provided.Recommendations are subsequently formulated on how best to define absolute and relative chronologies. Future climato-stratigraphic alignments should provide (1) a clear statement of climate hypotheses involved, (2) a detailed understanding of environmental parameters controlling selected tracers and (3) a careful evaluation of the synchronicity of aligned paleoclimatic records. We underline the need to (1) systematically report quantitative estimates of relative and absolute age uncertainties, (2) assess the coherence of chronologies when comparing different records, and (3) integrate these uncertainties in paleoclimatic interpretations and comparisons with climate simulations.Finally, we provide a sequence of major climatic events with associated age uncertainties for the period 140-105 ka, which should serve as a new benchmark to disentangle mechanisms of the Earth system’s response to orbital forcing and evaluate transient climate simulations.[caption id="attachment_369" align="alignnone" width="1220"] Sequence of major climatic events across the period 140-100 ka. (Lower panel) Main paleoclimatic records. A. Obliquity (dashed grey) and 65°N summer (June 21) insolation (black). B. EDC CO2 (purple) and CH4 (grey) concentrations. C. NGRIP (thick black) and NEEM (dashed black) ice d18O. Dark red and blue bars mark the recent GI and GS nomenclature defined in Greenland ice cores {. D. EDC dD (grey). All ice core records are presented on the AICC2012 time scale. E. Calcite d18O records from the Chinese Sanbao SB41 (light brown), SB23 (intermediate brown) and SB25 (dark brown) speleothems. F. Calcite d18O records from the Italian Corchia CC5 (140-125 ka, dark brown), CC7 (lighter brown) and CC28 (117-100 ka, dark brown) speleothems. G. Percentage of temperature tree pollen (dark pink) and Mediterranean Sclerophylls pollen (purple) from the Greek Ioannina sequence presented on the original orbital-tuning time scale (section Comparison of different alignment ). H. Benthic foraminifera d13C records from the North Atlantic MD95-2042 core (dark green) and the Southern Ocean MD02-2488 core (blue), both presented on AICC2012 (sections Benthic d18O vs. temperature proxy alignments in two high-latitude cores and Comparison of different alignment ). I. Global mean sea level variations (black). J. Ice rafted detritus (IRD) from the North Atlantic ODP 980 core presented on the AICC2012 time scale. Horizontal grey bars mark the North Atlantic cold events H11, C26, C25 and C24 defined in marine sediments. Horizontal grey arrows in panels G-H illustrate the age dispersions induced by the use of different alignment methods applied in marine core MD95-2042 and the Ioannina continental sequence (section Comparison of different alignment ). (Upper panel) Timing and dating uncertainties of major paleoclimatic events. Using the same colour code as for records presented in the lower panel, thick vertical lines mark the date of events. Thin horizontal lines mark the 1s “internal” dating uncertainty within the archive (i.e. relevant when comparing the timing of events within the same archive). Shaded rectangles highlight the 1s combined dating uncertainty, which includes the “internal” age uncertainty, the alignment error (for lake and marine sediments) and the absolute dating uncertainty of the used time scale. Arrows mark the period of deglaciation (blue), of the LIG interval (red) and of the last glacial inception (green). Events are characterised by a unique number and highlighted by red crosses on dedicated records in the lower panel.[/caption]&#160;ReferencesGovina, 1,*,** , E. Capronb,*,**, P. C. Tzedakisc, S. Verheydend,2, B. Ghalebe, C. Hillaire-Marcele, G. St-Ongef, J. S. Stonerg, F. Bassinoth, L. Bazinh, T. Blunieri, N. Combourieu-Neboutj, A. El Ouahabik, D. Gentyh, R. Gersondel, P. Jimenez-Amatm, A. Landaish, B. Martratk, V. Masson-Delmotteh, F. Parreninn, M.-S. Seidenkrantzo, D. Veresn,3, C. Waelbroeckh, R. Zahnp&#160;a MARUM – Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse, 28359 Bremen, Germany.b British Antarctic Survey, High Cross, Madingley Road, CB3 0ET Cambridge, UKc Environmental Change Research Centre, Department of Geography, University College London, London WC1E 6BT, UKd Royal Belgian Institute of Natural Sciences, Jennerstraat 13, B-1000 Brussels, Belgiume GEOTOP, Université du Québec à Montréal, Montréal (Qc) H3C 3P8, Canadaf Institut des sciences de la mer de Rimouski (ISMER), Canada Research Chair in Marine Geology, Université du Québec à Rimouski, Rimouski, Canada &#38; GEOTOP Research Centerg College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, 104 CEOAS Admin Bldg., Corvallis, Oregon 97331-5503 USAh Institut Pierre-Simon Laplace/Laboratoire des Sciences du Climat et de l’Environnement, UMR 8212, CEA-CNRS-UVSQ, 91190 Gif-sur-Yvette, Francei Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Denmarkj UMR 7194 CNRS "Histoire Naturelle de l'Homme Préhistorique", Département de Préhistoire, Muséum national d'histoire naturelle, Institut de Paléontologie Humaine, 75013 Paris, Francek Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDÆA), Spanish Council for Scientific Research (CSIC), 08034 Barcelona, Spainl Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, D-27570 Bremerhaven, Germanym Institute of Environmental Science and Technology and Department of Geography, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spainn Laboratoire de Glaciologie et Géophysique de l’Environnement, UJF, CNRS, 54 rue Molière, 38402 St Martin d’Hères, Franceo Centre for Past Climate Studies, Department of Geoscience, Aarhus University, Høegh-Guldsbergs Gade 2, Aarhus C DK-8000, Denmarkp Institució Catalana de Recerca i Estudis Avançats (ICREA) and Institut de Ciència i Tecnologia Ambientals (ICTA), Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, SpainPaper in press in Quaternary Science Reviews&#160;