GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Other types  (2)
Document type
Source
Language
Years
  • 1
    Publication Date: 2023-11-14
    Description: Agulhas leakage, the warm and salty inflow of Indian Ocean water into the Atlantic Ocean, is of importance for the climate-relevant Atlantic Meridional Overturning Circulation. South of Africa, the eastward turning Agulhas Current sheds Agulhas rings, cyclones and filaments of order 100 km that carry the Indian Ocean water into the Cape Basin and further into the Atlantic. Here, we show that the resolution of submesoscale flows of order 10 km in an ocean model leads to 40 % more Agulhas leakage and more realistic Cape Basin water-masses compared to a parallel non-submesoscale resolving simulation. Moreover, we show that submesoscale flows strengthen shear-edge eddies and in consequence lee cyclones at the northern edge of the Agulhas Current, as well as the leakage pathway in the region of the filaments that takes place outside of mesoscale eddies. This indicates that the increase in leakage can be attributed to stronger Agulhas filaments, when submesoscale flows are resolved.
    Description: Leakage of warm, salty waters from the Indian Ocean into the Atlantic increases by up to 40 % in high-resolution numerical ocean model simulations, suggesting that low-resolution models underestimate this key part of the global meridional overturning circulation.
    Description: Agence Nationale de la Recherche (French National Research Agency) https://doi.org/10.13039/501100001665
    Description: https://hdl.handle.net/20.500.12085/c572cde8-a82c-4c2d-9bd7-288dfc8f1939
    Description: https://www.aoml.noaa.gov/phod/gdp/data.php
    Description: https://resources.marine.copernicus.eu/?option=com_csw&view=details&product_id=GLOBAL_REANALYSIS_PHY_001_030
    Description: https://resources.marine.copernicus.eu/?option=com_csw&view=details&product_id=SEALEVEL_GLO_PHY_L4_REP_OBSERVATIONS_008_047
    Keywords: ddc:551.46 ; Climate and Earth system modelling ; Physical oceanography
    Language: English
    Type: doc-type:article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2022-06-26
    Description: Warming of the North Atlantic region in climate history often was associated with massive melting of the Greenland Ice Sheet. To identify the meltwater's impacts and isolate these from internal variability and other global warming factors, we run single‐forcing simulations including small ensembles using three complex climate models differing only in their ocean components. In 200‐year‐long preindustrial climate simulations, we identify robust consequences of abruptly increasing Greenland runoff by 0.05 Sv: sea level rise of 44 ± 10 cm, subpolar North Atlantic surface cooling of 0.7°C, and a moderate AMOC decline of 1.1–2.0 Sv. The latter two emerge in under three decades—and reverse on the same timescale after the perturbation ends in year 100. The ocean translates the step‐change perturbation into a multidecadal‐to‐centennial signature in the deep overturning circulation. In all simulations, internal variability creates notable uncertainty in estimating trends, time of emergence, and duration of the response.
    Description: Plain Language Summary: Enhanced melting of Greenland's glaciers is considered to be a major player in past rapid climate transitions and anticipated to soon impact ocean circulation under current global warming. Global warming triggers complex processes and feedbacks, of which greater amounts of meltwater slowing the large‐scale ocean circulation is only one. To better understand the sensitivity of the real but also the model ocean to just this meltwater, we run idealized experiments with up‐to‐date climate models, which use the same atmosphere and land but different ocean components. We find that sea level rise, cooling of the North Atlantic region, and slowing of the ocean circulation are responses common to all models while regional magnitudes of these responses differ considerably. Once we stop adding freshwater, all three models show that surface temperature and ocean circulation recover as quickly (or slowly) as they changed at the beginning of the experiment. Sea level rise is a lasting impact though.
    Description: Key Points: Sudden increase in Greenland freshwater release is turned into century scale change by deep ocean dynamics. Upper ocean responses to moderately enhanced freshwater release from Greenland reverse on the same timescale once release ceases. Ocean model formulation affects regional expressions but basin‐scale responses are robust, so is the timing on decadal to centennial scales.
    Description: Bundesministerium für Bildung und Forschung (BMBF) http://dx.doi.org/10.13039/501100002347
    Keywords: ddc:551.6
    Language: English
    Type: doc-type:article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...