scholarly journals The impact of upwelling on the intensification of anticyclonic ocean eddies in the Caribbean Sea

Ocean Science ◽  
2019 ◽  
Vol 15 (6) ◽  
pp. 1419-1437 ◽  
Author(s):  
Carine G. van der Boog ◽  
Julie D. Pietrzak ◽  
Henk A. Dijkstra ◽  
Nils Brüggemann ◽  
René M. van Westen ◽  
...  
Keyword(s):  
Coastal Upwelling ◽  
Caribbean Sea ◽  
Vertical Shear ◽  
Ekman Transport ◽  
Density Gradients ◽  
River Plumes ◽  
Salinity Gradients ◽  
The Caribbean ◽  
Anticyclonic Eddies ◽  
The Impact

Abstract. The mesoscale variability in the Caribbean Sea is dominated by anticyclonic eddies that are formed in the eastern part of the basin. These anticyclones intensify on their path westward while they pass the coastal upwelling region along the Venezuelan and Colombian coast. In this study, we used a regional model to show that this westward intensification of Caribbean anticyclones is steered by the advection of cold upwelling filaments. Following the thermal wind balance, the increased horizontal density gradients result in an increase in the vertical shear of the anticyclones and in their westward intensification. To assess the impact of variations in upwelling on the anticyclones, several simulations were performed in which the northward Ekman transport (and thus the upwelling strength) is altered. As expected, stronger (weaker) upwelling is associated with stronger (weaker) offshore cooling and a stronger (weaker) westward intensification of the anticyclones. Moreover, the simulations with weaker upwelling show farther advection of the Amazon and Orinoco River plumes into the basin. As a result, in these simulations the horizontal density gradients were predominantly set by horizontal salinity gradients. The importance of the horizontal density gradients driven by temperature, which are associated with the upwelling, increased with increasing upwelling strength. The results of this study highlight that both upwelling and the advection of the river plumes affect the life cycle of mesoscale eddies in the Caribbean Sea.

scholarly journals The Impact of Upwelling on the Intensification of Anticyclonic Ocean Eddies in the Caribbean Sea

2019 ◽  
Author(s):  
Carine G. van der Boog ◽  
Julie D. Pietrzak ◽  
Henk A. Dijkstra ◽  
Nils Brüggemann ◽  
René M. van Westen ◽  
...  
Keyword(s):  
Coastal Upwelling ◽  
Caribbean Sea ◽  
Vertical Shear ◽  
Ekman Transport ◽  
Density Gradients ◽  
River Plumes ◽  
The Caribbean ◽  
Western Side ◽  
Anticyclonic Eddies ◽  
The Impact

Abstract. The mesoscale variability in the Caribbean Sea is dominated by anticyclonic eddies that are formed in the eastern part of the basin. These anticyclones intensify on their path westward while they pass the coastal upwelling region along the Venezuelan and Colombian coast. In this study, we used a regional model to show that this westward intensification of Caribbean anticyclones is driven by the advection of cold upwelling filaments. These dense filaments are advected by the anticyclones, leading to an increase of the horizontal density gradients at the western side of the anticyclones. Following the thermal wind balance, the increased density gradients result in an increase of the vertical shear of the anticyclones and to their westward intensification. To assess the impact of variations in upwelling on the anticyclones, several simulations were performed in which the northward Ekman transport (and thus the upwelling strength) is altered. As expected, stronger (weaker) upwelling is associated with more stronger (weaker) offshore cooling and a more (less) westward intensification of the anticyclones. The simulations with weaker upwelling show farther advection of the Amazon and Orinoco River plumes into the basin. The dispersion of the river plumes affects the formation process of the anticyclones, where the horizontal density gradients were mainly determined by the salinity gradients of the river plume and not by temperature gradients that were associated with upwelling.

scholarly journals The Surface Circulation of the Caribbean Sea and the Gulf of Mexico as Inferred from Satellite Altimetry

2009 ◽  
Vol 39 (3) ◽  
pp. 640-657 ◽  
Author(s):  
Aida Alvera-Azcárate ◽  
Alexander Barth ◽  
Robert H. Weisberg
Keyword(s):  
Gulf Of Mexico ◽  
Time Scales ◽  
Satellite Altimetry ◽  
Southern Oscillation ◽  
Caribbean Sea ◽  
Vertical Shear ◽  
Loop Current ◽  
Surface Circulation ◽  
The Caribbean ◽  
Anticyclonic Eddies

Abstract The surface circulation of the Caribbean Sea and Gulf of Mexico is studied using 13 years of satellite altimetry data. Variability in the Caribbean Sea is evident over several time scales. At the annual scale, sea surface height (SSH) varies mainly by a seasonal steric effect. Interannually, a longer cycle affects the SSH slope across the current and hence the intensity of the Caribbean Current. This cycle is found to be related to changes in the wind intensity, the wind stress curl, and El Niño–Southern Oscillation. At shorter time scales, eddies and meanders are observed in the Caribbean Current, and their propagation speed is explained by baroclinic instabilities under the combined effect of vertical shear and the β effect. Then the Loop Current (LC) is considered, focusing on the anticyclonic eddies shed by it and the intrusion of the LC into the Gulf of Mexico through time. Twelve of the 21 anticyclonic eddies observed to detach from the LC are shed from July to September, suggesting a seasonality in the timing of these events. Also, a relation is found between the intrusion of the LC into the Gulf of Mexico and the size of the eddies shed from it: larger intrusions trigger smaller eddies. A series of extreme LC intrusions into the Gulf of Mexico, when the LC is observed as far as 92°W, are described. The analyses herein suggest that the frequency of such events has increased in recent years, with only one event occurring in 1993 versus three from 2002 to 2006. Transport through the Straits of Florida appears to decrease during these extreme intrusions.

Influence of fishers’ behaviour on the catchability of surface tuna schools in the Venezuelan purse-seiner fishery in the Caribbean Sea

1999 ◽  
Vol 56 (3) ◽  
pp. 394-406
Author(s):  
Daniel Gaertner ◽  
Mauricio Pagavino ◽  
Jesus Marcano
Keyword(s):  
Environmental Factors ◽  
Daily Activity ◽  
Caribbean Sea ◽  
Catch Rate ◽  
Causal Network ◽  
Fine Scale ◽  
Network Approach ◽  
Logistic Regressions ◽  
The Caribbean ◽  
The Impact

The influence of Venezuelan skippers' behaviour on the catchability of surface tuna schools was modelled using logistic regressions. Data obtained from observers onboard purse seiners indicated that fishers' fine-scale decisions, such as chasing and setting a school, were influenced by (i) the skipper's skill, (ii) the fishing equipment used (e.g., whether a bird radar was used or not), (iii) the features of the tuna school, and (iv) some environmental factors. The connections among the decisions related to the fishing process and these variables were synthesized in a causal network approach. Results clearly showed that schools (i) composed by fishes under 2 kg and (ii) where biomass was lower than 5 metric tons were disregarded by fishers. Because fishers used these thresholds to decide when to set the net, modifications in their behaviour over the years may introduce serious biases in the analysis of any catch rate and abundance relationship. An average daily activity record of a purse seiner shows the proportion of time spent in searching and in setting activities and highlights the impact that the use of new fishing equipment may have on fishing power.

scholarly journals Arribazones de Sargassum en la costa norte occidental de Cuba

2020 ◽  
Vol 2 (1) ◽  
pp. 19-30
Author(s):  
G. Arencibia-Carballo ◽  
J.M. Irañeta Batallán ◽  
J. Morell ◽  
A.R. Moreira González
Keyword(s):  
Negative Impact ◽  
Caribbean Sea ◽  
Geographic Area ◽  
Tourism Industry ◽  
Caribbean Region ◽  
Western Coast ◽  
Tidal Zone ◽  
The North ◽  
The Caribbean ◽  
The Impact

The pelagic macroalgae finches of the Sargassum genus in the Caribbean Sea currently represent a very natural problem due to their negative impact on the tourism industry, fishing industry, the environment and society in general. This work presents an above report of Sargassum that occurred on the north western coast of the Cuban archipelago in March 2019. The macroalgae species identified in the tidal zone were Sargassum fluitans and S. natans, and the specific geographic area where the impact of the upheaval occurred was from the west of Matan-zas bay to Mariel bay. The finches of these macroalgae were cataloged with a moderate magnitude compared to other reports in the Mexican Caribbean and in the Dominican Republic. This order of magnitude was cataloged based on its covered area of 169.3 km and its distribution along the coast in large patches, but very fragmented, despite the prevailing winds from the first quadrant (from north to east) during this period. Other events of this type reported in Cuba and the Caribbean region are taken up and discussed. Keywords: Caribbean Sea, Sargassum fluitans, Sargassum natans, Cuba.

Frontal variability and its impact on chlorophyll in the Arabian Sea

2020 ◽  
Author(s):  
Yuntao Wang ◽  
Wentao Ma ◽  
Feng Zhou ◽  
Chai Fei
Keyword(s):  
Arabian Sea ◽  
Coastal Upwelling ◽  
Cold Water ◽  
Southwest Monsoon ◽  
Ocean Dynamics ◽  
Ekman Transport ◽  
Spatial And Temporal Variability ◽  
Anomalous Field ◽  
The North ◽  
The Impact

<p>Sixteen years satellite observations are used to investigate the frontogenesis, frontal variability and its impact on chlorophyll in the Arabian Sea. Large frontal probability (FP) and high chlorophyll mainly happens near the coast, e.g., near Somalia and Oman, and its value generally decreases with offshore distance. An Empirical Orthogonal Function (EOF) is used to disentangle the spatial and temporal variability of front and chlorophyll. Prominent seasonal cycle of frontal activities is identified, peaking in summer when southwest wind prevails. The seasonality for chlorophyll is same with wind and front near Somalia, which largely impacted by monsoon. During summer, the southwest monsoon drives offshore Ekman transport and induces coastal upwelling. It transports subsurface cold water and nutrients to the surface layer, which generates fronts and enhances chlorophyll, respectively. The frontal activities can be used as an indicator to determine the chlorophyll level that high chlorophyll happens when frontal probability gets higher than 2%. At anomalous field, stronger wind can induce higher frontal activities and chlorophyll. The impact of wind on frontogenesis can extend 1,000km offshore and a simplified linear regression is applied to quantify their relationship. The variability of wind leads chlorophyll by lags increasing with distance, indicating a horizontal offshore transport of coastal water. In winter, the northeast wind is not upwelling favorable, thus the frontal activities and chlorophyll are greatly reduced off Somalia. During this period, large chlorophyll is found in the north off Oman because of mixing, thus its relationship with front is less pronounced. In the upwelling regions, fronts act as an intermedia process that connecting the wind forcing and responses of ecosystem. The frontal activities in Arabian Sea is fundamentally important to improve our understanding of monsoon related ocean dynamics.</p>

scholarly journals On the Impact of the Caribbean Counter Current in the Guajira Upwelling System

2021 ◽  
Vol 8 ◽  
Author(s):  
Alejandro Orfila ◽  
Claudia P. Urbano-Latorre ◽  
Juan M. Sayol ◽  
Stephanie Gonzalez-Montes ◽  
Alejandro Caceres-Euse ◽  
...  
Keyword(s):  
Ocean Circulation ◽  
Caribbean Sea ◽  
High Concentration ◽  
Near Surface ◽  
Relaxation Phase ◽  
Upwelling System ◽  
South Central ◽  
The Caribbean ◽  
Counter Current ◽  
The Impact

The variability of La Guajira upwelling system, in the south-central Caribbean Sea, is strongly influenced by the intensity and location of the atmospheric Caribbean Low-Level Jet (CLLJ), a near-surface branch of the easterlies, as well as by the regional ocean circulation. During favorable conditions (i.e., strong easterlies blowing almost parallel to the coast), upwelling is enhanced and a large amount of primary productivity occurs in La Guajira area. In contrast, during relatively mild wind conditions, the CLLJ is misaligned to the coast and the Caribbean Counter Current (CCC, locally also known as the Darien Current), which forms as a branch from the Panama-Colombia Gyre, flows northeastward over the continental shelf advecting waters from the southwestern Caribbean basin toward La Guajira. The CCC has a clear signature at the surface layer that extends from the Darien Gulf toward La Guajira peninsula during mild wind periods, while disappears during the months of strong winds. The direction and the magnitude of the easterlies, and more specifically of the CLLJ, control the position and pathway of the CCC, which extends more than 900 km in the southern Caribbean Sea during May, June, August, September, and October. The high concentration of chlorophyll-a at the sea surface evidenced by satellite-based color images is semi-seasonally modulated by the CLLJ, which during its relaxation phase allows the irruption of the CCC toward the east up to La Guajira.

scholarly journals A mechanism for freshening the Caribbean Sea in pre‐Ice Age time

2014 ◽  
Vol 29 (6) ◽  
pp. 508-517 ◽  
Author(s):  
Alberto M. Mestas‐Nuñez ◽  
Peter Molnar
Keyword(s):  
Caribbean Sea ◽  
Ice Age ◽  
The Caribbean

scholarly journals Processes, Challenges and Optimisation of Rum Production from Molasses—A Contemporary Review

Fermentation ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 21
Author(s):  
Tinashe Mangwanda ◽  
Joel B. Johnson ◽  
Janice S. Mani ◽  
Steve Jackson ◽  
Shaneel Chandra ◽  
...  
Keyword(s):  
Management Practices ◽  
Scientific Literature ◽  
Asia Pacific ◽  
Yeast Strains ◽  
Challenges And Opportunities ◽  
The Caribbean ◽  
The Impact ◽  
Production Industry ◽  
Stringent Quality

The rum industry is currently worth USD 16 billion, with production concentrated in tropical countries of the Caribbean and Asia-Pacific regions. The primary feedstock for rum production is sugar cane molasses, a by-product of sugar refineries. The main variables known to affect rum quality include the composition of the molasses, the length of fermentation, and the type of barrels and length of time used for aging the rum. The goal of this review is to provide an overview of the impact of these variables on rum quality, and to highlight current challenges and opportunities in the production of rum from molasses. In order to achieve this, we review the relevant contemporary scientific literature on these topics. The major contemporary challenges in the rum production industry include minimising the effects of variability in feedstock quality, ensuring the fermentation process runs to completion, preventing microbial contamination, and the selection and maintenance of yeast strains providing optimum ethanol production. Stringent quality management practices are required to ensure consistency in the quality and organoleptic properties of the rum from batch to batch. Further research is required to fully understand the influences of many of these variables on the final quality of the rum produced.

scholarly journals Implications of GNSS-Inferred Tropopause Altitude Associated with Terrestrial Gamma-Ray Flashes

2021 ◽  
Vol 13 (10) ◽  
pp. 1939
Author(s):  
Tao Xian ◽  
Gaopeng Lu ◽  
Hongbo Zhang ◽  
Yongping Wang ◽  
Shaolin Xiong ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Thermal Structure ◽  
Deep Convection ◽  
Caribbean Sea ◽  
Negative Bias ◽  
Upper Troposphere ◽  
Cold Anomaly ◽  
The Caribbean ◽  
Geographic Distributions

The thermal structure of the environmental atmosphere associated with Terrestrial Gamma-ray Flashes (TGFs) is investigated with the combined observations from several detectors (FERMI, RHESSI, and Insight-HXMT) and GNSS-RO (SAC-C, COSMIC, GRACE, TerraSAR-X, and MetOp-A). The geographic distributions of TGF-related tropopause altitude and climatology are similar. The regional TGF-related tropopause altitude in Africa and the Caribbean Sea is 0.1–0.4 km lower than the climatology, whereas that in Asia is 0.1–0.2 km higher. Most of the TGF-related tropopause altitudes are slightly higher than the climatology, while some of them have a slightly negative bias. The subtropical TGF-producing thunderstorms are warmer in the troposphere and have a colder and higher tropopause over land than the ocean. There is no significant land–ocean difference in the thermal structure for the tropical TGF-producing thunderstorms. The TGF-producing thunderstorms have a cold anomaly in the middle and upper troposphere and have stronger anomalies than the deep convection found in previous studies.

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