A5079482474- Oceanographic and Atmospheric Processes
- Geology and Paleoclimatology Research
- Methane Hydrates and Related Phenomena
- Arctic and Antarctic ice dynamics
- Geological Studies and Exploration
- Marine and coastal ecosystems
- Atmospheric and Environmental Gas Dynamics
- Climate variability and models
- Maritime Navigation and Safety
- Offshore Engineering and Technologies
- Underwater Acoustics Research
- Underwater Vehicles and Communication Systems
- Marine and environmental studies
- Geological formations and processes
- Arctic and Russian Policy Studies
- earthquake and tectonic studies
- Geological and Tectonic Studies in Latin America
- Ionosphere and magnetosphere dynamics
- Hydrocarbon exploration and reservoir analysis
- Ship Hydrodynamics and Maneuverability
- Water Quality Monitoring Technologies
- Spacecraft and Cryogenic Technologies
- Acoustic Wave Phenomena Research
- Geological and Geophysical Studies Worldwide
- Scientific Research and Discoveries
University of Bremen
2009-2024
Federal Maritime and Hydrographic Agency of Germany
2022-2024
The Atlantic Meridional Overturning Circulation (AMOC) extends from the Southern Ocean to northern North Atlantic, transporting heat northwards throughout South and sinking carbon nutrients into deep ocean. Climate models indicate that changes AMOC both herald drive climate shifts. Intensive trans-basin observational systems have been put in place continuously monitor meridional volume transport variability, some cases, heat, freshwater transport. These programs used diagnose magnitude...
Abstract Chlorofluorocarbon (component CFC-11) and hydrographic data from 1997, 1999, 2001 are presented to track the large-scale spreading of Upper Labrador Sea Water (ULSW) in subpolar gyre North Atlantic Ocean. ULSW is CFC rich comparatively low salinity. It located on top denser “classical” (LSW), defined density range σΘ = 27.68–27.74 kg m−3. follows pathways similar LSW has entered eastern Atlantic. Despite gaps, CFC-11 inventories (40°–65°N) could be estimated within 11%. The...
Abstract Recently formed Labrador Seawater (LSW) and overflow water from Denmark Strait (DSOW) are main components of the Atlantic Meridional Overturning Circulation. Both exhibit a distinct chlorofluorocarbon (CFC) maximum. Here we use 25 years CFC observations in to study features circulation LSW DSOW. From data, age fraction young deep inferred. Due superior spatial data resolution compared former attempts, regional differences spreading velocity pathways become evident, dependent on...
The southwestern part of the subpolar North Atlantic east Grand Banks Newfoundland and Flemish Cap is a crucial area for Meridional Overturning Circulation. Here exchange between subtropical gyre takes place, southward flowing cold fresh water replaced by northward warm salty within Current (NAC). As long-term experiment, circulation has been studied seven repeat hydrographic sections along (2003–2011), 2 year time series current velocities at continental slope (2009–2011), 19 years sea...
Measurements of chlorofluorocarbon inventories during 1997–2003 allow the detection and quantification significant changes in formation rates two modes Labrador Sea Water (LSW): Upper (ULSW) deep LSW, both here defined fixed density intervals. Both contribute to cold limb Meridional Overturning Circulation. Results reveal that lighter ULSW formed since mid‐1990s has started replace large pool LSW stored western North Atlantic. Formation was absent 1997–2003. compensated for this absence...
Abstract In the western North Atlantic, warm and saline water is brought by Atlantic Current (NAC) from subtropics into subpolar gyre. Four inverted echo sounders with high precision pressure sensors (PIES) were moored between 47°40′N 52°30′N to study main pathways of NAC eastern basin. The array configuration that forms three segments (northern, central, southern) allows partitioning some assessment flow paths through different Mid‐Atlantic Ridge fracture zones. We exploit correlation...
Abstract Labrador Sea Water (LSW) is one of the main contributors to lower limb Atlantic Meridional Overturning Circulation. In this study, we explore sensitivity LSW formation model resolution, Greenland melt, absence high‐frequency atmospheric phenomena, and changes in precipitation. We use five numerical simulations at both (1/4)° (1/12)° resolutions. A kinematic subduction approach used obtain rate over period 2004 2016. The control simulation, with showed a mean annual production 1.9 Sv...
Abstract Subpolar Mode Water (SPMW) is an important water mass originating in the eastern North Atlantic. Its formation, subject to modification through oceanic interior mixing, can directly influence volume of contributing Atlantic meridional overturning circulation. Utilizing observation‐based data sets spanning from 1993 2018, we estimated formation rates and SPMW within isopycnal layers examined its temporal variability. Two complementary approaches were used estimate rate: a...
Marine heatwaves (MHWs), prolonged periods of unusually high ocean temperatures, have been observed worldwide and are expected to increase in both intensity frequency due anthropogenic climate change. This rise MHW has led significant biological ecological shifts, including changes species distributions, large-scale mortality, the decline or extinction local species. The tidal Elbe discharges into German Bight. It plays a crucial role region's ecology, serving as dynamic estuarine ecosystem...
Transient tracer observations from GLODAPv2 and more recent data are used tocompute transit time distributions (TTDs) for Labrador Sea Water. These TTDs then integratedbasin wide over the subpolar, subtropical tropical Atlantic. This allows to infer ventilation,export formation rates of LSW. We further devide LSW density range into an upper (ULSW) adeeper part (DLSW). The results reflect known variability formation, with high ratesof DLSW in 1990s after 2015, periods increased ULSW...
In 2003 and in 2005, hydrographic data provided sufficient spatial coverage the Labrador Sea to infer basin wide changes water mass characteristic of Upper Water (ULSW). The ULSW was considerably saltier warmer 2005 than 2003. Although convection leads mixing with salinity‐poor surface is opposed observed salinity trend, increased vertical homogeneity CTD profiles, increase thickness intensification potential vorticity minimum for isopycnals σ Θ = 27.700–27.734 kg/m 3 point winter which...
Abstract A new data set of temperature and salinity fields reconstructed from satellite altimetry between January 1993 April 2014 is combined with observations mesoscale eddies in the subpolar North Atlantic 40°N–55°N 43°W–20.5°W. The used to calculate meridional heat freshwater transports related propagation crossing 47°N, a latitude close boundary subtropical gyres. largest by are observed western part Newfoundland Basin. Around 35–45% across 47°N stem individual isolated large...
Abstract Since climate model studies project a decline of the Atlantic Meridional Overturning Circulation (AMOC) in 21st century, monitoring AMOC changes remains essential. While variability is expected to be coherent across latitudes on longer than decadal timescales, connectivity inter‐annual and seasonal timescales less clear. Model observational estimates disagree regions meridional observations at multiple are needed study its connectivity. We calculate basin‐wide volume transports...
Abstract. The Atlantic inventory of anthropogenic carbon (Cant) and its changes between 1990 2020 are investigated by applying the transit time distribution (TTD) method to tracer data. In contrast previous TTD applications, here we take into account admixture old waters free tracers. greatest difference from other methods based on direct observations is higher Cant storage in deep ocean. Estimations decadal increase yield general a smaller share North larger South compared our results....
The deep water formation in the Labrador Sea is simulated with Finite-Element Sea-Ice Ocean Model (FESOM) a regionally focused, but globally covered model setup. has regional resolution of up to 7 km, and simulations cover time period 1958–2009. We evaluate capability setup reproduce realistic Sea. Two classes modeled Water (LSW), lighter upper LSW (uLSW) denser (dLSW), are analyzed. Their layer thicknesses compared uLSW dLSW derived from observations region for interval 1988–2009. results...
Abstract Surface geostrophic velocity fields derived from satellite altimetry between January 1993 and April 2014 are used to detect investigate eddies in the North Atlantic 40°N–55°N 60°W–10°W. Focus is on a zonal section along 47°N, roughly at boundary subpolar subtropical gyres. Sea surface temperature data quantify anomalies associated with respective fluxes related these eddies. Identified eddy pathways across 47°N mean background full‐depth ship observations carried out 11 cruises 2003...
Abstract Eddies generated off the west Greenland coast modulate deep convection in Labrador Sea, while there are still open questions related to their formation mechanisms. Using 11 years (2008–18) of output from a NEMO model configured with 1/60° nest we present patterns baroclinic and barotropic instability coast. We highlight generation Irminger Rings at Cape Desolation boundary current eddies location Overturning Subpolar North Atlantic Program (OSNAP) West section. In between these...