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Author
Le Sommer, Julien ; Chassignet, E.P. ; Wallcraft, A. J.
Title
Ocean Circulation Modeling for Operational Oceanography: Current Status and Future Challenges
Type
$loc['typeBook Chapter']
Year
2018
Publication
New Frontiers in Operational Oceanography
Abbreviated Journal
Volume
Issue
Pages
289-305
Keywords
OCEAN MODELING ; OCEAN CIRCULATION ; PARAMETERIZATIONS
Abstract
This chapter focuses on ocean circulation models used in operational oceanography, physical oceanography and climate science. Ocean circulation models area particular branch of ocean numerical modeling that focuses on the representation of ocean physical properties over spatial scales ranging from the global scale to less than a kilometer and time scales ranging from hours to decades. As such, they are an essential build-ing block for operational oceanography systems and their design receives a lot of attention from operational and research centers.
Address
Corporate Author
Thesis
Publisher
GODAE OceanView
Place of Publication
Tallahassee, FL
Editor
Chassignet, E. P., A. Pascual, J. Tintoré, and J. Verron
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ user @
Serial
948
Permanent link to this record
Author
Winterbottom, H
Title
The Development of a High-Resolution Coupled Atmosphere-Ocean Model and Applications Toward Understanding the Limiting Factors for Tropical Cyclone Intensity Prediction
Type
$loc['typeManuscript']
Year
2010
Publication
Abbreviated Journal
Volume
Issue
Pages
Keywords
Tropical cyclone vortex initialization, Coupled atmosphere-ocean model
Abstract
The prediction of tropical cyclone (TC) motion has improved greatly in recent decades. However, similar trends remain absent with respect to TC intensity prediction. Several hypotheses have been proposed attempting to explain why dynamical NWP models struggle to predict TC intensity. The leading candidates are as follows: (1) the lack of an evolving ocean (i.e., sea-surface temperature) boundary condition which responds as a function of the atmosphere (e.g., TC) forcing, (2) inappropriate initial conditions for the TC vortex (e.g., lack of data assimilation methods), (3) NWP model grid-length resolutions which are unable to resolve the temporal and length scale for the features believed responsible for TC vortex intensity. modulations (i.e., eye-wall dynamics, momentum transport, vortex Rossby wave interactions, etc.), and (4) physical parametrization which do not adequately represent the air-sea interactions observed during TC passage. In this study, a coupling algorithm for two independent, high-resolution, and state-of-the-art atmosphere and ocean models is developed. The atmosphere model -- the Advanced Weather Research and Forecasting (WRF-ARW) model is coupled to the HYbrid Coordinate Ocean Model (HYCOM) using a (UNIX) platform independent and innovative coupling methodology. Further, within the WRF-ARW framework, a dynamic initialization algorithm is developed to specify the TC vortex initial condition while preserving the synoptic-scale environment. Each of the tools developed in this study is implemented for a selected case-study: TC Bertha (2008) and TC Gustav (2008) for the coupled-model and TC vortex initialization, respectively. The experiment results suggest that the successful prediction (with respect to the observations) for both the ocean response and the TC intensity cannot be achieved by simply incorporating (i.e., coupling) an ocean model and/or by improving the initial structure for the TC. Rather the physical parametrization governing the air-sea interactions is suggested as the one of the weaknesses for the NWP model. This hypothesis is (indirectly) supported through a diagnostic evaluation of the synoptic-scale features (e.g., sea-level pressure and the deep-layer mean wind beyond the influence of the TC) while the assimilated TC vortex is nudged toward the observed intensity value. It is found -- in the case of TC Gustav (2008) using WRF-ARW, that as the assimilated TC vortex intensity approaches that of the observed, the balance between the mass and momentum states for WRF-ARW is compromised leading to unrealistic features for the environmental sea-level pressure and deep-layer (800- to 200-hPa) mean wind surrounding the TC. Forcing WRF-ARW to assimilate a TC vortex of the observed maximum wind-speed intensity may ultimately compromise the prediction for the TC's motion and subsequently mitigate any gains for the corresponding intensity prediction.Suggestions for additions to the coupled atmosphere-ocean model include a wave-model (WAVEWATCH3), the assimilation of troposphere thermodynamic observations, and modifications to the existing atmospheric boundary-layer parametrization. The current suite of atmosphere model parametrizations do not accurately simulate the observed azimuthal and radial variations for the exchange coefficients (e.g., drag and enthalpy) that have been indicated as potentialpredictor variables for TC intensity modulation. However, these modifications should be implemented only after the limitations for the current coupled-model and TC vortex initialization methods are fully evaluated.
Address
Department of Meteorology
Corporate Author
Thesis
$loc['Ph.D. thesis']
Publisher
Florida State University
Place of Publication
Tallahassee, FL
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
572
Permanent link to this record
Author
Yu, P
Title
Development of New Techniques for Assimilating Satellite Altimetry Data into Ocean Models
Type
$loc['typeManuscript']
Year
2006
Publication
Abbreviated Journal
Volume
Issue
Pages
Keywords
Data Assimilation, Reduced Space, First Baroclinic Mode, Ocean Models, Vertical Normal Mode Decomposition, Variational
Abstract
State of the art fully three-dimensional ocean models are very computationally expensive and their adjoints are even more resource intensive. However, many features of interest are approximated by the first baroclinic mode over much of the ocean, especially in the lower and mid latitude regions. Based on this dynamical feature, a new type of data assimilation scheme to assimilate sea surface height (SSH) data, a reduced-space adjoint technique, is developed and implemented with a three-dimensional model using vertical normal mode decomposition. The technique is tested with the Navy Coastal Ocean Model (NCOM) configured to simulate the Gulf of Mexico. The assimilation procedure works by minimizing the cost function, which generalizes the misfit between the observations and their counterpart model variables. The “forward” model is integrated for the period during which the data are assimilated. Vertical normal mode decomposition retrieves the first baroclinic mode, and the data misfit between the model outputs and observations is calculated. Adjoint equations based on a one-active-layer reduced gravity model, which approximates the first baroclinic mode, are integrated backward in time to get the gradient of the cost function with respect to the control variables (velocity and SSH of the first baroclinic mode). The gradient is input to an optimization algorithm (the limited memory Broyden-Fletcher-Goldfarb-Shanno (BFGS) method is used for the cases presented here) to determine the new first baroclinic mode velocity and SSH fields, which are used to update the forward model variables at the initial time. Two main issues in the area of ocean data assimilation are addressed: 1. How can information provided only at the sea surface be transferred dynamically into deep layers? 2. How can information provided only locally, in limited oceanic regions, be horizontally transferred to ocean areas far away from the data-dense regions, but dynamically connected to it? The first problem is solved by the use of vertical normal mode decomposition, through which the vertical dependence of model variables is obtained. Analyses show that the first baroclinic mode SSH represents the full SSH field very closely in the model test domain, with a correlation of 93% in one of the experiments. One common way to solve the second issue is to lengthen the assimilation window in order to allow the dynamic model to propagate information to the data-sparse regions. However, this dramatically increases the computational cost, since many oceanic features move very slowly. An alternative solution to this is developed using a mapping method based on complex empirical orthogonal functions (EOF), which utilizes data from a much longer period than the assimilation cycle and deals with the information in space and time simultaneously. This method is applied to map satellite altimeter data from the ground track observation locations and times onto a regular spatial and temporal grid. Three different experiments are designed for testing the assimilation technique: two experiments assimilate SSH data produced from a model run to evaluate the method, and in the last experiment the technique is applied to TOPEX/Poseidon and Jason-1 altimeter data. The assimilation procedure converges in all experiments and reduces the error in the model fields. Since the adjoint, or “backward”, model is two-dimensional, the method is much more computationally efficient than if it were to use a fully three-dimensional backward model.
Address
Department of Oceanography
Corporate Author
Thesis
$loc['Ph.D. thesis']
Publisher
Florida State University
Place of Publication
Tallahassee, FL
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
ISBN
Medium
Area
Expedition
Conference
Funding
NSF, ONR, NASA
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
589
Permanent link to this record
Author
Todd, A.C. ; Morey, S.L. ; Chassignet, E.P.
Title
Circulation and cross-shelf transport in the Florida Big Bend
Type
$loc['typeJournal Article']
Year
2014
Publication
Journal of Marine Research
Abbreviated Journal
J Mar Res
Volume
72
Issue
6
Pages
445-475
Keywords
Coastal circulation ; ocean modeling ; larval transport ; gag grouper ; Florida Big Bend
Abstract
Address
Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
0022-2402
ISBN
Medium
Area
Expedition
Conference
Funding
BP/Deep-C, NOAA NGI, NASA/JPL/OVWST, ONR
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
148
Permanent link to this record
Author
Hiester, H.R. ; Morey, S.L. ; Dukhovskoy, D.S. ; Chassignet, E.P. ; Kourafalou, V.H. ; Hu, C.
Title
A topological approach for quantitative comparisons of ocean model fields to satellite ocean color data
Type
$loc['typeJournal Article']
Year
2016
Publication
Methods in Oceanography
Abbreviated Journal
Methods in Oceanography
Volume
17
Issue
Pages
232-250
Keywords
Satellite data ; Ocean model ; Ocean color ; Sea surface salinity ; Shape comparison ; Hausdorff distance
Abstract
Address
Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
2211-1220
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
78
Permanent link to this record
Author
Danabasoglu, G. ; Yeager, S.G. ; Kim, W.M. ; Behrens, E. ; Bentsen, M. ; Bi, D. ; Biastoch, A. ; Bleck, R. ; Böning, C. ; Bozec, A. ; Canuto, V.M. ; Cassou, C. ; Chassignet, E. ; Coward, A.C. ; Danilov, S. ; Diansky, N. ; Drange, H. ; Farneti, R. ; Fernandez, E. ; Fogli, P.G. ; Forget, G. ; Fujii, Y. ; Griffies, S.M. ; Gusev, A. ; Heimbach, P. ; Howard, A. ; Ilicak, M. ; Jung, T. ; Karspeck, A.R. ; Kelley, M. ; Large, W.G. ; Leboissetier, A. ; Lu, J. ; Madec, G. ; Marsland, S.J. ; Masina, S. ; Navarra, A. ; Nurser, A.J.G. ; Pirani, A. ; Romanou, A. ; Salas y Mélia, D. ; Samuels, B.L. ; Scheinert, M. ; Sidorenko, D. ; Sun, S. ; Treguier, A.-M. ; Tsujino, H. ; Uotila, P. ; Valcke, S. ; Voldoire, A. ; Wang, Q. ; Yashayaev, I.
Title
North Atlantic simulations in Coordinated Ocean-ice Reference Experiments phase II (CORE-II). Part II: Inter-annual to decadal variability
Type
$loc['typeJournal Article']
Year
2016
Publication
Ocean Modelling
Abbreviated Journal
Ocean Modelling
Volume
97
Issue
Pages
65-90
Keywords
Global ocean – sea-ice modelling ; Ocean model comparisons ; Atmospheric forcing ; Inter-annual to decadal variability and mechanisms ; Atlantic meridional overturning circulation variability ; Variability in the North Atlantic
Abstract
Address
Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
1463-5003
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
34
Permanent link to this record
Author
Downes, S.M. ; Farneti, R. ; Uotila, P. ; Griffies, S.M. ; Marsland, S.J. ; Bailey, D. ; Behrens, E. ; Bentsen, M. ; Bi, D. ; Biastoch, A. ; Böning, C. ; Bozec, A. ; Canuto, V.M. ; Chassignet, E. ; Danabasoglu, G. ; Danilov, S. ; Diansky, N. ; Drange, H. ; Fogli, P.G. ; Gusev, A. ; Howard, A. ; Ilicak, M. ; Jung, T. ; Kelley, M. ; Large, W.G. ; Leboissetier, A. ; Long, M. ; Lu, J. ; Masina, S. ; Mishra, A. ; Navarra, A. ; George Nurser, A.J. ; Patara, L. ; Samuels, B.L. ; Sidorenko, D. ; Spence, P. ; Tsujino, H. ; Wang, Q. ; Yeager, S.G.
Title
An assessment of Southern Ocean water masses and sea ice during 1988-2007 in a suite of interannual CORE-II simulations
Type
$loc['typeJournal Article']
Year
2015
Publication
Ocean Modelling
Abbreviated Journal
Ocean Modelling
Volume
94
Issue
Pages
67-94
Keywords
Southern Ocean ; CORE-II experiments ; Water masses ; Sea ice ; Ocean model intercomparison
Abstract
Address
Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
1463-5003
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
99
Permanent link to this record
Author
Danabasoglu, G. ; Yeager, S.G. ; Bailey, D. ; Behrens, E. ; Bentsen, M. ; Bi, D. ; Biastoch, A. ; Böning, C. ; Bozec, A. ; Canuto, V.M. ; Cassou, C. ; Chassignet, E. ; Coward, A.C. ; Danilov, S. ; Diansky, N. ; Drange, H. ; Farneti, R. ; Fernandez, E. ; Fogli, P.G. ; Forget, G. ; Fujii, Y. ; Griffies, S.M. ; Gusev, A. ; Heimbach, P. ; Howard, A. ; Jung, T. ; Kelley, M. ; Large, W.G. ; Leboissetier, A. ; Lu, J. ; Madec, G. ; Marsland, S.J. ; Masina, S. ; Navarra, A. ; George Nurser, A.J. ; Pirani, A. ; y Mélia, D.S. ; Samuels, B.L. ; Scheinert, M. ; Sidorenko, D. ; Treguier, A.-M. ; Tsujino, H. ; Uotila, P. ; Valcke, S. ; Voldoire, A. ; Wang, Q.
Title
North Atlantic simulations in Coordinated Ocean-ice Reference Experiments phase II (CORE-II). Part I: Mean states
Type
$loc['typeJournal Article']
Year
2014
Publication
Ocean Modelling
Abbreviated Journal
Ocean Modelling
Volume
73
Issue
Pages
76-107
Keywords
Global ocean–sea-ice modelling Ocean model comparisons Atmospheric forcing Experimental design Atlantic meridional overturning circulation North Atlantic simulations
Abstract
Address
Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
1463-5003
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
159
Permanent link to this record
Author
Morey, S.L. ; Dukhovskoy, D.S.
Title
A downscaling method for simulating deep current interactions with topography – Application to the Sigsbee Escarpment
Type
$loc['typeJournal Article']
Year
2013
Publication
Ocean Modelling
Abbreviated Journal
Ocean Modelling
Volume
69
Issue
Pages
50-63
Keywords
Ocean modeling ; Model nesting ; Topographic flows ; USA ; Gulf of Mexico ; Sigsbee Escarpment
Abstract
Address
Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
1463-5003
ISBN
Medium
Area
Expedition
Conference
Funding
DeepStar, HYCOM Consortium
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
183
Permanent link to this record
Author
Srinivasan, A. ; Chassignet, E.P. ; Bertino, L. ; Brankart, J.M. ; Brasseur, P. ; Chin, T.M. ; Counillon, F. ; Cummings, J.A. ; Mariano, A.J. ; Smedstad, O.M. ; Thacker, W.C.
Title
A comparison of sequential assimilation schemes for ocean prediction with the HYbrid Coordinate Ocean Model (HYCOM): Twin experiments with static forecast error covariances
Type
$loc['typeJournal Article']
Year
2011
Publication
Ocean Modelling
Abbreviated Journal
Ocean Modelling
Volume
37
Issue
3-4
Pages
85-111
Keywords
Data assimilation ; Ocean modeling ; Ocean prediction ; Twin experiments ; Sequential assimilation ; MVOI ; EnOI ; SEEK ; ROIF ; EnROIF
Abstract
Address
Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
1463-5003
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
320
Permanent link to this record