edu.ucar.opensky::articles:23397 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-25T15:09:45.816040 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7736v56 https://doi.org/10.3334/CDIAC/OTG.NDP093_GLODAPv2 https Related Dataset #1 Global Ocean Data Analysis Project, Version 2 (GLODAPv2), ORNL/CDIAC-162, ND-P093 Internal variability dominates over externally forced ocean circulation changes seen through CFCS 2020-05-16T00:00:00Z publication https://n2t.org/ark:/85065/d7736v56 https://doi.org/10.1029/2020GL087585 Lester, J. G. author Lovenduski, N. S. author Graven, H. D. author Long, Matthew author Lindsay, Keith author UCAR/NCAR - Library publisher Observations of oceanic transient tracers have indicated that the circulation in the Southern Ocean has changed in recent decades, potentially driven by changes in external climate forcing. Here, we use the CESM Large Ensemble to analyze changes in two oceanic tracers that are affected by ocean circulation: the partial pressure of chlorofluorocarbon-12 (pCFC12) and the idealized model tracer Ideal Age (IAGE) over the 1991 to 2005 period. The small ensemble mean change in IAGE suggests that there has been very little externally forced change in Southern Ocean circulation over this period, in contrast to strong internal variability. Further, our analysis implies that real-world observations of changes in pCFC12 may not be a robust way to characterize externally driven changes in Southern Ocean circulation because of the large internal variability in pCFC12 changes exhibited by the individual ensemble members. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. None eng geoscientificInformation