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
  • AGU (American Geophysical Union)  (3)
  • Elsevier  (2)
  • AMS (American Meteorological Society)
  • 2010-2014  (5)
  • 2011  (5)
Document type
Publisher
Years
  • 2010-2014  (5)
Year
  • 1
    Publication Date: 2020-08-05
    Description: On interannual to decadal times scales, model simulations suggest a strong relationship between anomalies in the deep water formation rate, the strength of the subpolar gyre, and the meridional overturning circulation in the North Atlantic. Whether this is valid, can only be confirmed by continuous, long observational time series. Several measurement components are already in place, but crucial arrays to obtain time series of the meridional volume and heat transport in the subpolar North Atlantic are still missing. Here we summarize the recent developments of the deep water formation rates and the subpolar gyre transports. We discuss how existing observational components in the subpolar North Atlantic could be supplemented to provide long-term monitoring of the meridional heat and volume transport. Through a combined analysis of observations and model results the temporal and spatial scales that had to be covered with instruments are discussed, together with the key regions with the highest variability in the velocity and temperature fields.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2017-06-20
    Description: Multi-decadal weakening trend of the equatorial Pacific easterly winds since 1960 has reversed after 1993. The trend reversal has induced cooling (shallow thermocline) trend in the equatorial western Pacific before 1993, followed by a warming (deep thermocline) trend from 1993 to the present. All available atmospheric reanalysis products corroborate the trend reversal during the two multi-decadal periods. The magnitudes of the multi-decadal trends of the easterly winds, however, differ among the reanalysis products. The trend reversals of regional ocean circulations are assessed using linear regressions between wind and transport anomalies in an eddy-permitting numerical model, suggesting that since 1993 the Indonesian Throughflow and the Leeuwin Current transports have also reversed their multi-decadal weakening trends. Key Points: - There have been reversals of the multi-decadal weakening trends of trade winds - Different reanalysis products capture different trends in trade winds
    Type: Article , PeerReviewed
    Format: text
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2019-09-23
    Description: Reconstructions of the spatial pattern of recent multi-decadal sea level trends in the Indian Ocean (IO) indicate a zonally-extended band in the southern tropics where sea level has substantially fallen between the 1960s and 1990s; the decline is consistent with the observed subsurface cooling associated with a shoaling thermocline in this region. Here the origin and spatio-temporal characteristics of these trends are elucidated by a sequence of ocean model simulations. Whereas interannual variability in the southwestern tropical IO appears mainly governed by IO atmospheric forcing, longer term changes in the south tropical IO involve a strong contribution from the western Pacific via wave transmission of thermocline anomalies through the Indonesian Archipelago, and their subsequent westward propagation by baroclinic Rossby waves. The late 20th-century IO subsurface cooling trend reversed in the 1990s, reflecting the major regime shift in the tropical Pacific easterlies associated with the Pacific Decadal Oscillation.
    Type: Article , PeerReviewed
    Format: text
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2024-04-08
    Description: For the past 50 years it has been assumed that the principal pathway for the deep limb of the Atlantic Meridional Overturning Circulation (AMOC) is the Deep Western Boundary Current (DWBC). However, recent observations of Lagrangian floats have shown that the DWBC is not necessarily a unique, dominant, or continuous pathway for these deep waters. A significant portion of the deep water export from the subpolar to the subtropical gyres follows a pathway through the interior of the Newfoundland and subtropical basins, which is constrained by the western boundary and the western flank of the Mid-Atlantic Ridge. The hypothesis that deep eddy-driven recirculation gyres are a mechanism for partitioning the deep limb of the AMOC into the DWBC and this interior pathway is investigated here. Eulerian and Lagrangian analyses of the output of ocean general circulation models at eddy-resolving, eddy-permitting, and non-eddy permitting resolutions are used to test this hypothesis. Eddy-driven recirculation gyres, simulated in the eddy-resolving and eddy-permitting models and similar to recirculations inferred from hydrographic data, are shown to shape the export pathways of deep water from the subpolar to the subtropical gyres.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2023-01-31
    Description: Vast amounts of methane hydrates are potentially stored in sediments along the continental margins, owing their stability to low temperature – high pressure conditions. Global warming could destabilize these hydrates and cause a release of methane (CH 4) into the water column and possibly the atmosphere. Since the Arctic has and will be warmed considerably, Arctic bottom water temperatures and their future evolution projected by a climate model were analyzed. The resulting warming is spatially inhomogeneous, with the strongest impact on shallow regions affected by Atlantic inflow. Within the next 100 years, the warming affects 25% of shallow and mid-depth regions containing methane hydrates. Release of methane from melting hydrates in these areas could enhance ocean acidification and oxygen depletion in the water column. The impact of methane release on global warming, however, would not be significant within the considered time span.
    Type: Article , PeerReviewed
    Format: text
    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...