An open ocean region in Neoproterozoic glaciations would have to be narrow to allow equatorial ice sheets

• Published in: Geophysical Research Letters
• Main Authors: Rodehacke, C.B., Voigt, Aiko, Ziemen, F., Abbot, D.S.
• Other Authors: Danish Meteorological Institute (DMI), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL), Max Planck Institute for Meteorology (MPI-M), Max-Planck-Gesellschaft, Department of Geophysical Sciences Chicago, University of Chicago
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology; Ice Sheet; Sea ice
• Online Access: https://hal.science/hal-01091217; https://hal.science/hal-01091217/document; https://hal.science/hal-01091217/file/2013GL057582.pdf; https://doi.org/10.1002/2013GL057582

International audience A major goal of understanding Neoproterozoic glaciations and determining their effect on the evolution of life and Earth's atmosphere is establishing whether and how much open ocean there was during them. Geological evidence tells us that continental ice sheets had to flow into the ocean near the equator during these glaciations. Here we drive the Parallel Ice Sheet Model with output from four simulations of the ECHAM5/Max Planck Institute Ocean Model atmosphere-ocean general circulation model with successively narrower open ocean regions. We find that extensive equatorial ice sheets form on marine margins if sea ice extends to within about 20° latitude of the equator or less (Jormungand-like and hard snowball states), but do not form if there is more open ocean than this. Given uncertainty in topographical reconstruction and ice sheet ablation parameterizations, we perform extensive sensitivity tests to confirm the robustness of our main conclusions. Key Points Low-elevation eq. ice sheets form if sea ice extends to 20 degrees latitude This limits the amount of open ocean possible in Neoproterozoic glaciations This result is robust to large parameter variations ©2013. American Geophysical Union. All Rights Reserved.