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A numerical investigation of the atmosphere-ocean thermal contrast over the coastal upwelling region of Cabo Frio, Brazil

DOURADAO, M.; OLIVEIRA, A. Pereira De
Fonte: CENTRO CIENCIAS ATMOSFERA UNAM Publicador: CENTRO CIENCIAS ATMOSFERA UNAM
Tipo: Artigo de Revista Científica
Português
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59.15587%
An one-dimensional atmospheric second order closure model, coupled to an oceanic mixed layer model, is used to investigate the short term variation of the atmospheric and oceanic boundary layers in the coastal upwelling area of Cabo Frio, Brazil (23 degrees S, 42 degrees 08`W). The numerical simulations were carried out to evaluate the impact caused by the thermal contrast between atmosphere and ocean on the vertical extent and other properties of both atmospheric and oceanic boundary layers. The numerical simulations were designed taking as reference the observations carried out during the passage of a cold front that disrupted the upwelling regime in Cabo Frio in July of 1992. The simulations indicated that in 10 hours the mechanical mixing, sustained by a constant background flow of 10 in s(-1), increases the atmospheric boundary layer in 214 in when the atmosphere is initially 2 K warmer than the ocean (positive thermal contrast observed during upwelling regime). For an atmosphere initially -2 K colder than the ocean (negative thermal contrast observed during passage of the cold front), the incipient thermal convection intensifies the mechanical mixing increasing the vertical extent of the atmospheric boundary layer in 360 in. The vertical evolution of the atmospheric boundary layer is consistent with the observations carried out in Cabo Frio during upwelling condition. When the upwelling is disrupted...

Ocean thermal energy conversion plants : experimental and analytical study of mixing and recirculation

Jirka, Gerhard H.; Johnson, R. Peter; Fry, David J.; Harleman, Donald R.F.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 7474729 bytes; application/pdf
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Ocean thermal energy conversion (OTEC) is a method of generating power using the vertical temperature gradient of the tropical ocean as an energy source. Experimental and analytical studies have been carried out to determine the characteristics of the temperature and velocity fields induced in the surrounding ocean by the operation of an OTEC plant. The condition of recirculation, i.e. the reentering of mixed discharge water back into the plant intake, was of particular interest because of its adverse effect on plant efficiency. The studies were directed at the mixed discharge concept, in which the evaporator and condenser water flows are exhausted jointly at the approximate level of the ambient ocean thermocline. The OTEC plant was of the symmetric spar-buoy type with radial or separate discharge configurations. A distinctly stratified ocean with uniform, ambient current velocity was assumed. The following conclusions are obtained: The recirculation potential of an OTEC plant in a stagnant ocean is determined by the interaction of the jet discharge zone and a double sink return flow (one sink being the evaporator intake, the other the jet entrainment). This process occurs in the near-field of an OTEC plant up to a distance of about three times the ocean mixed layer depth. The stratified internal flow beyond this zone has little effect on recirculation...

Incorporation of the new turbulence closure schemes in the Princeton Ocean Model (POM)

Souza, José Francisco Almeida de; Azevedo, José Luiz Lima de; Oliveira, Leopoldo Rota de; Soares, Ivan Dias; Mata, Maurício Magalhães
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
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One of the most challenging issues in oceanography is the simulation of the mixing processes, which are responsible for diffusion of momentum, heat, salt, sediments, etc. In the modeling of flow, the hydrodynamic model simulates the properties of the mean flow while the turbulence model, coupled to the first, is responsible for simulating the mixing processes. In this article it is used the Princeton Ocean Model (POM), which includes the well known turbulent closure model q2 − q2L of Mellor & Yamada (1982), level 2.5. To add flexibility to the modeling, the k − ε and k − ω models, which belong to the same class of models, are incorporated into the POM and two test cases, one involving the deepening of the oceanic mixed layer and the other addressing the estuarine circulation, are carried out to allow the quality assessment of the models implementation in the computer code. The tests indicated that the model implementation was adequate. Comparing with the original model available in the Princeton Ocean Model, the results showed that the model k − ε tends to overestimate the mixed layer, while the model k − ω underestimates it, within an acceptable range of tolerance. In terms of estuarine circulation, the k − ε and k − ω models showed a greater capacity of mixing at the bottom of the estuarine mixing zone and also at the surface layer.; Uma das questões mais desafiadoras em oceanografia é a simulação dos processos de mistura...

Shear and stability at the base of the mixed layer in the Arctic Ocean the role of inertial motions

Suh, George Y.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
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The Arctic environment changed significantly over recent decades and declines in perennial sea ice and thickness concentrations have been frequently observed. Current predictive models providing researchers with conservative estimates of sea ice concentrations, the lack of observations and understanding of the physical processes that promote changes in sea ice create inaccuracies that need to be improved. A fusion of buoy observations, satellite derived ice concentrations, and modeled wind data are made in this thesis to provide a better insight into sea ice inertial motions and its influence on the processes that occur in the Arctic Ocean mixed layer and to investigate whether these processes can be parameterized to improve predictive models. Observations made in the Canadian Basin and the Transpolar Drift by high resolution Autonomous Ocean Flux Buoys (AOFBs), SSMI and AMSR-E satellite derived ice concentrations, and ERA-Interim winds are used to examine the relationships between winds, ice coverage and sea ice inertial oscillations. Data collected from AOFBs and collocated Ice-Tethered Profilers (ITPs) are analyzed to investigate whether ocean mixed layer inertial oscillations contribute to shear instability at the base of the mixed layer...

The climatological seasonal response of the ocean mixed layer in the equatorial and tropical Pacific Ocean

Ries, Harry J.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
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59.197188%
Seasonal changes of mixed layer depth (MLD) can be related to the forcing by the net surface heating and wind speed. This is shown in this study by comparing the monthly mixed layer depth from temperature profiles in the Bauer-Robinson Numerical Atlas with monthly net surface heating and wind speed obtained from the Weare Marine Climatic Atlas of the Tropical Pacific Ocean. Using a conceptual model based on mixed layer physics, ocean response and atmospheric forcing are examined using the Obukhov mixing length. A pattern in the seasonal variation of upwelling along the Equator is also examined. The model links the atmospheric and oceanic climatologies through the derived MLD (oceanic data) and Obukhov mixing lengths (forcing data). The results show a high degree of pattern similarity between the seasonal response of the ocean and the seasonal changes in atmospheric forcing. The pattern of seasonal influence on MLD at the Equator is very weak in comparison to that of the tropics and sub-tropics. Keywords: Ocean models; Atmosphere models; Equatorial regions; Mixed layer marine; Air water interactions; Theses. (EDC)

Optical effects on ocean mixed layer dynamics.

White, Jonathan W.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
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59.1%
Improvements to the specification of ocean optical characteristics in mixed layer dynamics are explored. The effects of reflection (albedo), refraction and attenuation of solar radiation on mixed layer dynamics are examined. Parameterization schemes are developed to characterize the attenuation of individual spectral components of total solar radiation and the refraction of direct solar radiation. The effect of these parameterization schemes on mixed layer processes is evaluated analytically and numerically. A one-dimensional mixed layer model is used to examine the sensitivity of predicted mixed layer thermal structure to individual parameterizations. The thermal structure differences that result over long and short periods using the different parameterizations show that the accuracy of mixed layer predictions is significantly affected by the method used to describe the penetration of solar radiation into the ocean

Cloud effects on ocean mixed layer in the northeast Pacific Ocean.

Wu, Pao-Kun
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
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69.23871%
This study was conducted to examine the effects of clouds on the ocean mixed layer, both short-term and seasonal. It utilized data collected at Ocean Station Papa in the northeast Pacific. Two numerical modeling simulations were performed (i.e., with variable cloud and with variable precipitation). The results for the variable cloud simulation indicated that the downward surface buoyancy flux and longer daylight period in summer may induce a significant albedo effect of cloud on ocean mixed layer. The upward surface buoyancy flux and longer night period in winter will result in a pronounced greenhouse effect of cloud on ocean mixed layer. The results of variable precipitation simulation showed that the mixed layer is most sensitive to precipitation between October and March. Model predictions are verified using data at Ocean Station Papa for monthly and yearly mean values of cloud cover and precipitation. The comparison between model prediction and observations shows that the mean values of observed MLD (H = 60.9 m) are much deeper than model-predicted values (H = 36.5 m)

Optimal linear fitting for objective determination of ocean mixed layer depth from glider profiles (Proof)

Fan, C.W.; Chu, Peter C.
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Artigo de Revista Científica
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Journal of Atmospheric and Oceanic Technology, American Meteorological Society; The article of record as published may be located at http://dx.doi.org/10.1175/2010JTECHO804.1; A new optimal linear fitting method has been developed to determine mixed layer depth from profile data. This methodology includes three steps: 1) fitting the profile data from the first point near the surface to a depth using a linear polynomial, 2) computing the error ratio of absolute bias of few data points below that depth versus the root-mean-square error of data points from the surface to that depth between observed and fitted data, and 3) finding the depth (i.e., the mixed layer depth) with maximum error ratio. Temperature profiles in the western North Atlantic Ocean over 14 November–5 December 2007, collected from two gliders (Seagliders) deployed by the Naval Oceanographic Office (NAVOCEANO), are used to demonstrate the capability of this method. The mean quality index (1.0 for perfect determination) for determining mixed layer depth is greater than 0.97, which is much higher than the critical value of 0.8 for well-defined mixed layer depth with that index.

Simulation of more realistic upper ocean process from an OGCM with a new ocean mixed layer model

Noh, Yign; Jang, Chan Joo; Kim, Cheol-Ho; Yamagata, Toshio; Chu, Peter C.
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Artigo de Revista Científica
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Journal of Physical Oceanography, American Meteorological Society, 32, 1284-1307.; A new ocean mixed layer model (OMLM) was embedded into an ocean general circulation model (OGCM) with the aim of providing an OGCM that is ideal for application to a climate model by predicting the sea surface temperature (SST) more accurately. The results from the new OMLM showed a significant improvement in the prediction of SST compared to the cases of constant vertical mixing and the vertical mixing scheme by Pacanowski and Philander. More accurate prediction of the SST from the new OMLM reduces the magnitude of the restoring term in the surface heat flux and thus provides a simulated ocean that can be coupled to the atmospheric general circulation model more naturally. The new OMLM was also shown to improve various other features of the OGCM such as the mixed layer depth and the equatorial circulation.

A comparison of modeled and observed ocean mixed layer behavior in a sea breeze influenced coastal region

Cross, Patrick S.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
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Approved for public release; distribution is unlimited.; A high temporal resolution data set from a mooring in Monterey Bay, California was analyzed and used to calculate heat and momentum fluxes for the purpose of forcing two ocean mixed layer models. The time frame for the study was September, 1992, a period representative of the sea breeze circulation frequently affecting this and other coastal regions. The models used were that of Price, Weller and Pinkel (1986), a Richardson number based mixing model, and Garwood (1977), a model based on the turbulent kinetic energy budget within the mixed layer. Both models were analyzed with respect to their ability to reproduce the observed diurnal variation of the temperature and depth of the mixed layer. Although the model predictions agree reasonably well with observations in regards to the phase of the diurnal temperature cycle, they were seen to underpredict its magnitude, particularly the nocturnal cooling. This lack of cooling in the models relative to the ocean could be due to penetrative convection, non-steady state turbulence, and/or diurnal advection present in the ocean but not in one or both models. Additionally, the models exhibited an upward temperature trend relative to the data which caused progressively increasing stratification. This trend was used to approximate the magnitude of vertical advective effects.

Tropical cyclone footprint in the ocean mixed layer observed by Argo in the Northwest Pacific

Fu, HongLi; Wang, Xidong; Chu, Peter C.; Zhang, Xuefeng; Han, Guijun; Li, Wei
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Artigo de Revista Científica
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The article of record as published may be located at http://dx.doi.org/10.1002/2014JC010316; This study systematically investigated the ocean mixed layer responses to tropical cyclone (TC) using available Argo profiles during the period of 1998–2011 in the northwest Pacific. Results reveal that isothermal layer (IL) deepening and isothermal layer (IL) cooling with evident rightward biases induced by strong TCs are clearer compared to the weak TCs. Likewise, the rightward biases of IL deepening and cooling induced by fast TCs are more obvious than that induced by slow TCs. The upwelling within TC’s eye is much stronger for the strong (slow) TCs than weak (fast) TCs. For the strong and slow TCs, the TC-induced rainfall reduces deepening of constant density layer (with its depth called the mixed layer depth, MLD), and in turn increases the barrier layer thickness (BLT). The initial BL prior to TC can restrict IL cooling more markedly under the weak and fast TCs than under the strong and slow TCs. The inertial oscillation is stronger induced by the strong (fast) TCs than by the weak (slow) TCs. In addition, the most pronounced TC-induced mixed layer deepening and IL cooling in July to October climatology occur in the subtropical gyre of the northwest Pacific with enhanced vertical diffusivity. The maximum increase of isothermal layer depth (ILD) and MLD is up to 5 m...

Deep mixed layer entrainment

Stone, Rebecca E
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
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79.10781%
Approved for public release; distribution is unlimited.; A bulk turbulence-closure mixed layer model is generalized to allow prediction of very deep polar sea mixing. The model includes unsteady three- component turbulent kinetic energy budgets. In addition to terms for shear production, pressure redistribution, and dissipation, special attention is devoted to realistic treatment of thermobaric enhancement of buoyancy flux and to Coriolis effect on turbulence. The model is initialized and verified with CTD data taken by R/V Valdivia in the Greenland Sea during winter 1993-1994. Model simulations show (1) mixed layer deepening is significantly enhanced when the thermal expansion coefficient's increase with pressure is included; (2) entrainment rate is sensitive to the direction of wind stress because of Coriolis; and (3) the predicted mixed layer depth evolution agrees qualitatively with the observations. Results demonstrate the importance of water column initial conditions, accurate representation of strong surface cooling events, and inclusion of the thermobaric effect on buoyancy, to determine the depth of mixing and ultimately the heat and salt flux into the deep ocean. Since coupling of the ocean to the atmosphere through deep mixed layers in polar regions is fundamental to our climate system...

Ocean mixed layer response to gap wind scenarios

Konstantinou, Nikolaos
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xvi, 63 p. : ill. ;
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This study focuses on understanding the oceanic response to gap outflow and the air-sea interaction precesses during the gap wind event between 26 and 28 February 2004 over the Gulf of Tehuantepec, Mexico. The U.S. Navy's Coupled Ocean Atmospheric Mesoscale Prediction Systems (COAMPS) and NPS Ocean Mixed Layer (OML) model was used to simulate the gap wind event and the temporal/spatial evolution of ocean response. Satellites, coincident in situ aircraft and AXBTs measurements of the sea surface temperature and the water temperature profiles collected during the Gulf of Tehuantepec Experiment (GOTEX) were used to define model initial conditions and aid the analysis of model results. Results for the OML simulations suggest measurable SST evolution as a result of the enhanced upper ocean mixing along the jet axes. Model sensitivity tests show the dominant effects of surface heat flux in generating upper ocean mixing while mechanical forcing by the strong wind of the gap outflow has secondary effects. Sensitivity tests also suggest that the thermocline structure is the most important factor in determing the magnitude of the ocean response while variations in SST are not sensitive to upwelling for a short time scale of several days. The study of COAMPS/OML simulations and satellite (SST) images confirms the existence of a secondary gap outflow source in the area.

Relationship between the sonic layer depth and mixed layer depth identified from U.S. Navy sea glider data

Villarreal, Vance A.
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Tipo: Tese de Doutorado
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Approved for public release; distribution is unlimited; The mixed layer depth (MLD) represents the upper ocean mixing, and the sonic layer depth (SLD) reveals the capacity of the upper ocean to trap acoustic energy and create a surface duct. A set of sea glider date from the Naval Oceanographic Office is used to identify the MLD and SLD at five locations. The maximum angle method is found to be the best among 17 existing MLD determination schemes of the four major methods (difference, gradient, curvature, and maximum angle). The maximum angle method is also found better than the currently used maximum value method in determining SLD. The optimally determined MLD and SLD by the maximum angle method from theNavy's glider data shows that one can swiftly, accurately, and objectively determine the MLD and SLD for operations in seas around the world.; Lieutenant, United States Navy

The role of salinity in equatorial mixed layers

Stougard, Pegeen O'Neil
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: x, 56 p.
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Approved for public release; distribution is unlimited; The purpose of this study was to understand the role of surface salinity flux in changing heat exchange between the ocean and the atmosphere by means of its effect on mixed layer dynamics. This was accomplished by a series of thirty-day mixed layer experiments using the one-dimensional Naval Postgraduate School (NPS) mixed layer model. Results from the NPS mixed layer model, forced with both idealized and in situ data from the western equatorial Pacific Ocean, demonstrated that salinity can play a significant role in potentially changing the surface heat flux, with its effect on the mixed layer depth and mixed layer temperature. Precipitation stabilized the mixed layer by creating a barrier layer, which slowed entrainment. The net accumulation of rain was found to be an important source of buoyancy that reduces entrainment by subsequent wind mixing events.; http://www.archive.org/details/roleofsalinityin00stou; Lieutenant, United States Navy

Thermodynamic feedback between cloud and ocean mixed layer

Garwood, Roland W., Jr.; Chu, Peter C.
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Artigo de Revista Científica
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Advances in Atmospheric Sciences, Vol. 7, No. 1; A cloud-ocean planetary boundary layer (OPBL) feedback mechanism is presented and tested in this paper. Water vapor, evaporated from the ocean surface or transported by the large-scale air flow, often forms convective clouds under a conditionally unstable lapse rate. The variable cloud cover and rainfall may have positive and negative feedback with the ocean mixed layer temperature and salinity structure. The coupling of the simplied Kuo's (1965) cumulus cloud model to the Kraus-Truner's (1967) ocean mixed layer model shows the existence of this feedback mechanism. The theory also predicts the generation of low frequency oscillation in the atmosphere and oceans.

An embedded mixed layer-ocean circulation model

Adamec, David; Elsberry, Russell L; Garwood, Roland W; Haney, Robert Lee
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Relatório
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The rationale and numerical technique of embedding an oceanic bulk mixed layer model with a multi-level primitive equation model is presented. In addition to the usual prognostic variables that exist in a multi-level primitive equation model, the embedded model predicts the depth of the well mixed layer as well as the jumps in temperature and velocity that occur at the base of that layer. The depth of the mixed layer need not coincide with any of the fixed model levels used in the primitive equations calculations. In addition to advective changes, the mixed layer can deepen by entrainment and it can reform at a shallower depth in the absence of entrainment. When the mixed layer reforms at a shallower depth, the vertical profile of temperature below, the new, shallower mixed layer is adjusted to fit the fixed-level structure used in the primitive equations calculations using a method which conserves heat, momentum and potential energy. Finally, a dynamic stability condition, which includes a consideration of both the vertical current shear and the vertical temperature gradient, is introduced in place of the traditional 'convective adjustment)'. A two-dimensional version of the model is used to test the embedded model formulations and to study the response of the ocean to a stationary axisymmetric hurricane. The model results indicate a strong interdependence between vertical turbulent mixing and advection of heat; The work reported herein was initially supported by the Naval Postgraduate School Foundation Research Program with funds provided by the Chief of Naval Research. Subsequent support was provided by the Office of Naval Research...

Deepening of the ocean mixed layer at the northern Patagonian continental shelf: a numerical study

Zanella, Juan; Alvarez, Ezequiel; Pescio, Andres; Dragani, Walter
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/05/2014 Português
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A possible deepening of the ocean mixed layer was investigated at a selected point of the Patagonian continental shelf where a significant positive wind speed trend was estimated. Using a 1-dimensional vertical numerical model (S2P3) forced by atmospheric data from NCEP/NCAR I reanalysis and tidal constituents from TPXO 7.2 global model on a long term simulation (1979-2011), it was found that the mixed layer thickness presents a significant and positive trend of 10.1 +/- 1.4 cm/yr. Several numerical experiments were carried out in order to evaluate the impact of the different atmospheric variables (surface zonal and latitudinal wind components, air temperature, atmospheric pressure, specific humidity and cloud coverage) considered in this study. As a result it was found that an increase in the wind speed can be considered as the main responsible of the ocean mixed layer deepening at the selected location of the Patagonian continental shelf. A possible increasing in the mixed layer thickness could be directly impacting on the sea surface temperature. Preliminary results obtained in this paper show that a slight but significant cooling in the temperature of the sea upper layer (of the order of 1 C every 50 years) could be happening since some decades ago at the northern Patagonian continental shelf waters.; Comment: 16 pages...

On the annual cycle of the sea surface temperature and the mixed layer depth in the Gulf of México.

MENDOZA,V. M.; VILLANUEVA,E. E.; ADEM,J.
Fonte: Centro de Ciencias de la Atmósfera, UNAM Publicador: Centro de Ciencias de la Atmósfera, UNAM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2005 Português
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Using an integrated mixed layer model we carry out a simulation of the annual cycle of the sea surface temperature (SST) and of the mixed layer depth (MLD) in the Gulf of México. We also compute the annual cycle of the entrainment velocity in the deepest region of the Gulf of México. The model is based on the thermal energy equation and on an equation of mechanical and thermal energy balance based on the Kraus-Turner theory; both equations are coupled and are vertically integrated in the mixed layer. The model equations are solved in a uniform grid of 25 km in the Gulf of México, the northwestern region of the Caribbean Sea and the eastern coast of Florida. The surface ocean current velocity and the atmospheric variables are prescribed in the model using observed values. We show the importance of the Ekman pumping in the entrainment velocity. We found that the upwelling plays an important role in increasing the entrainment velocity, producing an important reduction in the SST and diminishing the depth of the mixed layer in the Campeche Bay. In the rest of the Gulf of México the downwelling tends to reduce the entrainment velocity, increasing the SST and the MLD. Comparison of the computed annual cycle of the SST and the MLD with the corresponding observations reported by Robinson (1973)...

Sea surface temperature and mixed layer depth changes due to cold-air outbreak in the Gulf of Mexico

VILLANUEVA,E. E.; MENDOZA,V. M.; ADEM,J.
Fonte: Centro de Ciencias de la Atmósfera, UNAM Publicador: Centro de Ciencias de la Atmósfera, UNAM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2010 Português
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The impact of a cold-air outbreak (CAO) on the mixed layer in the Gulf of México (GoM), during the period 18-23 October 1999, is shown in this work. A numerical model, based on the thermal energy equation and the balance equation between the thermal and mechanical energies, is used for computing both, the sea surface temperature (SST) and the sea mixed layer depth (MLD) changes due to atmospheric forcing before and during the CAO. The importance of the contributions to the temperature tendency by thermal forcing at the surface, the vertical entrainment of cold water from the thermocline, the horizontal transport of thermal energy by ocean currents and by turbulent eddies in the mixed layer are analyzed, as well as the contributions to the entrainment velocity by deepening of the mixed layer and the Ekman's pumping velocity. During the passage of the CAO on the GoM the SST changes were markedly influenced by the increase in the surface wind speed. At the end of the period the experiments show that the vertical entrainment turned out to be the most determining process in the cooling of the mixed layer, even overhead of the latent and sensible heat fluxes and the horizontal transport by ocean currents and by turbulent eddies.