Eddies in the North Greenland Sea and Fram Strait From Satellite Altimetry, SAR and High‐Resolution Model Data

AbstractThe influence of a high horizontal resolution (5–15 km) on the general circulation and hydrography in the North Atlantic is investigated using the Finite Element Sea Ice–Ocean Model (FESOM). We find a stronger shift of the upper-ocean circulation and water mass properties during the model spinup in the high-resolution model version compared to the low-resolution (~1°) control run. In quasi equilibrium, the high-resolution model is able to reduce typical low-resolution model biases. Especially, it exhibits a weaker salinification of the North Atlantic subpolar gyre and a reduced mixed layer depth in the Labrador Sea. However, during the spinup adjustment, we see that initially improved high-resolution features partially reduce over time: the strength of the Atlantic overturning and the path of the North Atlantic Current are not maintained, and hence hydrographic biases known from low-resolution ocean models return in the high-resolution quasi-equilibrium state. We identify long baroclinic Rossby waves as a potential cause for the strong upper-ocean adjustment of the high-resolution model and conclude that a high horizontal resolution improves the state of the modeled ocean but the model integration length should be chosen carefully.

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Mesoscale eddy statistics and implications for parameterization refinements from a diagnosis of a high resolution model of the North Pacific

Ocean Modelling ◽

10.1016/j.ocemod.2010.02.004 ◽

2010 ◽

Vol 33 (3-4) ◽

pp. 205-223 ◽

Cited By ~ 7

Author(s):

Hiroyuki Tsujino ◽

Shiro Nishikawa ◽

Kei Sakamoto ◽

Hideyuki Nakano ◽

Hiroshi Ishizaki

Keyword(s):

High Resolution ◽

North Pacific ◽

Mesoscale Eddy ◽

The North ◽

Resolution Model ◽

High Resolution Model ◽

The North Pacific

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Freshwater distribution in the Arctic Ocean: Simulation with a high-resolution model and model-data comparison

Journal of Geophysical Research Atmospheres ◽

10.1029/2007jc004111 ◽

2008 ◽

Vol 113 (C5) ◽

Cited By ~ 35

Author(s):

Robert Newton ◽

Peter Schlosser ◽

Douglas G. Martinson ◽

Wieslaw Maslowski

Keyword(s):

High Resolution ◽

Arctic Ocean ◽

The Arctic ◽

Model Data ◽

Data Comparison ◽

The Arctic Ocean ◽

Resolution Model ◽

High Resolution Model ◽

Ocean Simulation

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Towards Direct Simulation of Future Tropical Cyclone Statistics in a High-Resolution Global Atmospheric Model

Advances in Meteorology ◽

10.1155/2010/915303 ◽

2010 ◽

Vol 2010 ◽

pp. 1-13 ◽

Cited By ~ 23

Author(s):

Michael F. Wehner ◽

G. Bala ◽

Phillip Duffy ◽

Arthur A. Mirin ◽

Raquel Romano

Keyword(s):

High Resolution ◽

Radiative Forcing ◽

General Circulation ◽

Circulation Model ◽

Atmospheric Model ◽

Tropical Storm ◽

Model Studies ◽

The North ◽

Resolution Model ◽

High Resolution Model

We present a set of high-resolution global atmospheric general circulation model (AGCM) simulations focusing on the model's ability to represent tropical storms and their statistics. We find that the model produces storms of hurricane strength with realistic dynamical features. We also find that tropical storm statistics are reasonable, both globally and in the north Atlantic, when compared to recent observations. The sensitivity of simulated tropical storm statistics to increases in sea surface temperature (SST) is also investigated, revealing that a credible late 21st century SST increase produced increases in simulated tropical storm numbers and intensities in all ocean basins. While this paper supports previous high-resolution model and theoretical findings that the frequency of very intense storms will increase in a warmer climate, it differs notably from previous medium and high-resolution model studies that show a global reduction in total tropical storm frequency. However, we are quick to point out that this particular model finding remains speculative due to a lack of radiative forcing changes in our time-slice experiments as well as a focus on the Northern hemisphere tropical storm seasons.

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Objective Center-Finding Algorithm for Tropical Cyclones in Numerical Models

Atmosphere ◽

10.3390/atmos10070376 ◽

2019 ◽

Vol 10 (7) ◽

pp. 376 ◽

Cited By ~ 1

Author(s):

Chengwu Zhao ◽

Junqiang Song ◽

Hongze Leng ◽

Juan Zhao

Keyword(s):

High Resolution ◽

Tropical Cyclones ◽

Numerical Models ◽

Small Scale ◽

Two Dimensional ◽

Model Data ◽

Centroid Algorithm ◽

Resolution Model ◽

High Resolution Model ◽

Resolution Simulation

Precise center-detection of tropical cyclones (TCs) is critical for dynamic analysis in high resolution model data. The existence of both smaller scale perturbations and larger scale circulations could reduce the accuracy of center positioning. In this study, an objective center-finding algorithm is developed based on a two-dimensional Fourier filter and a vorticity centroid algorithm. This proposed algorithm is able to automatically adjust its parameters according to the scale of the target vortex instead of using artificially prescribed parameters in previous research. What’s more, this new algorithm has been optimized and validated by a hundred idealized vortexes with different sizes and small-scale perturbations. A high-resolution simulation of Typhoon Soudelor (2015) was used to evaluate the performance of the new algorithm, and the proposed objective center-finding algorithm was found able to detect a precise and reliable center.

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Corrigendum to “Mesoscale eddy statistics and implications for parameterization refinements from a diagnosis of a high resolution model of the North Pacific” [Ocean Model. 33 (2010) 205–233]

Ocean Modelling ◽

10.1016/j.ocemod.2018.08.010 ◽

2018 ◽

Vol 131 ◽

pp. 101-102

Author(s):

Hiroyuki Tsujino ◽

Shiro Nishikawa ◽

Kei Sakamoto ◽

Hideyuki Nakano ◽

Hiroshi Ishizaki

Keyword(s):

High Resolution ◽

Pacific Ocean ◽

North Pacific ◽

North Pacific Ocean ◽

Mesoscale Eddy ◽

Ocean Model ◽

The North ◽

Resolution Model ◽

High Resolution Model ◽

The North Pacific

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Spreading dynamics of central Labrador and Irminger Sea Waters

10.5194/egusphere-egu2020-8602 ◽

2020 ◽

Author(s):

Patricia Handmann ◽

Martin Visbeck ◽

Arne Biastoch

Keyword(s):

High Resolution ◽

Ocean Model ◽

Shelf Break ◽

Labrador Sea ◽

Mean Velocity ◽

The North ◽

Irminger Sea ◽

First Results ◽

Resolution Model ◽

High Resolution Model

Water mass formation in the Subpolar North Atlantic and successive southward export, connects high latitudes with lower latitudes, as a part of the lower Atlantic meridional overturning (AMOC) limb. The role of regional importance, in particular the respective roles of the Labrador and Irminger Sea, in this process are in debate.&#160;This study analyses pathways connecting the Labrador and Irminger Sea in detail, using simulated Lagrangian particle trajectories. To give further insight on interconnectivity and flow patterns we used two setups with different velocity fields, a high-resolution ocean model (VIKING20X) and a gridded Argo float displacement climatology.&#160;Both setups indicate two distinct pathways with interconnectivity on the order of 20% of the total amount of seeded particles between the Labrador Sea and Irminger Sea. One pathway is following the recirculation in the Labrador Sea along the Greenland shelf break; the other is along the Newfoundland shelf break turning to the north/northwest at the Orphan-Knoll region towards the central Irminger Sea. For the Argo based advective-diffusive particle trajectory integration a 2.5&#8211;3.5 year travel time scale was derived between the Labrador and the Irminger Sea, while the experiments with the temporarily varying high-resolution model output revealed significantly shorter spreading times of about 1.5&#8211;2 years. While both pathways are represented in either setup, the pathway following the Newfoundland shelf break is populated stronger in the model-based experiments. In general we found that connectivity between the two regions is weaker in the experiments based on the climatological mean velocity output of the model than in those based on the Argo derived fields, first results indicate that this is due to stronger boundary currents and a weaker recirculation in the Labrador Sea.

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Flow paths and variability of the North Atlantic Current: A comparison of observations and a high-resolution model

Journal of Geophysical Research Oceans ◽

10.1002/2016jc012444 ◽

2017 ◽

Vol 122 (4) ◽

pp. 2686-2708 ◽

Cited By ~ 13

Author(s):

Tilia Breckenfelder ◽

Monika Rhein ◽

Achim Roessler ◽

Claus W. Böning ◽

Arne Biastoch ◽

...

Keyword(s):

High Resolution ◽

North Atlantic ◽

North Atlantic Current ◽

Flow Paths ◽

The North ◽

Resolution Model ◽

High Resolution Model ◽

The North Atlantic ◽

Atlantic Current

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Dissecting the Barotropic Transport in a High-resolution ocean model

10.5194/egusphere-egu2020-18490 ◽

2020 ◽

Author(s):

Martin Claus ◽

Yuan Wang ◽

Richard Greatbatch ◽

Jinyu Sheng

Keyword(s):

High Resolution ◽

North Atlantic ◽

Spatial Scales ◽

Ocean Model ◽

Water Model ◽

North Atlantic Current ◽

The North ◽

Circulation Patterns ◽

Resolution Model ◽

High Resolution Model

We present a method to decompose the time mean vertically averaged transport, as simulated by an high-resolution ocean model, into its four dominant components. These components are driven by the gradient of potential energy per unit area (PE), the divergence of the flux of time mean momentum (MMF) and eddy momentum (EMF), and the wind stress. Since the local vorticity budget and the bathymetry are noisy and dominated by small spatial scales, a barotropic shallow water model is used as a filter to diagnose the respective transports instead of integrating along lines of constant f/H. Applying this method to the output of a high-resolution model of the North Atlantic we find that PE is the most important driver, including the northwest corner. MMF is an important driver of transport around the Labrador Sea continental slope and, together with the EMF, it drives significant transport along the path of the Gulf Stream and North Atlantic current. Additionally, the circulation patterns driven by the EMF compares well with an estimate based on a satellite product. Hence, the presented method provides insights into the relative importance of the different dynamical processes that may drive barotropic transport in an ocean model. But it may also be used to isolate potential issues if a model misrepresents the barotropic transport.

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