Freshwater transport by eddies within the Bay of Bengal's central axis

Herron, Alexander J.; Bohman, Shannon M.; Gordon, Arnold L.

doi:10.1016/j.dsr.2022.103770

Cited by 4 publications

(3 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nonetheless, circulation reverses semi-annually, although not exactly matching wind direction, and in both seasons circulation is largely unorganised and characterised by meso-scale cyclonic (during the northeast monsoon) and anti-cyclonic (January to April) eddies (Chamarthi et al, 2008;Brewer et al, 2015;Behara and Vinayachandran, 2016;Rainville et al, 2022). Because the BoB receives a vast volume of freshwater on a seasonal time scale this water needs to be transported out of the bay (Behara and Vinayachandran, 2016;Herron et al, 2022). This is achieved largely by the East Indian Coastal Current (EICC) on the western side of the bay during November-January and by equator-ward flowing currents on the eastern side during both summer and winter (Chaitanya et al, 2014;Behara and Vinayachandran, 2016 and references therein, although not all studies agree on this e.g., Rainville et al, 2022).…”

Section: Introductionmentioning

confidence: 99%

Phylogeography of the Asian green mussel, Perna viridis: pronounced regional genetic differentiation is explained by major freshwater input into the Bay of Bengal

Gardner

Patterson

2023

Front. Mar. Sci.

View full text Add to dashboard Cite

The Asian green mussel (AGM), Perna viridis, is a mussel of ecological and economic importance throughout much of the tropical and subtropical regions of Asia, from China and Korea in the east to Oman on the Arabian Peninsula in the west. We collated published DNA sequence data and then analysed 467 bp of cytochrome c oxidase I gene (COI) sequence variation from 649 mussels (576 from SE Asia and 73 from India) to test for regional differentiation. Analysis of molecular variation, a haplotype network and a neighbour-joining tree all revealed significant differentiation between mussels from India and those from SE Asia. We observed a greater number of segregating sites (haplotypes) and private haplotypes than expected for Indian mussels compared to SE Asian mussels, based on the respective sample sizes. Tests of neutrality revealed population expansion or a recent selective sweep for only the mussels from India. We suggest that the differentiation of the Indian from the SE Asian mussels is explained by the pronounced seasonal input of freshwater into the northern Bay of Bengal area, which acts as a (semi-permeable) barrier to gene flow between the two regions (i.e., east versus west of the Bay). This suggestion is based on the oceanography of the region and is consistent with the biogeography and reports of genetic breaks in a range of taxa in this region. Further targetted sampling of AGMs from the east coast of India, Bangladesh and Myanmar is required to test this hypothesis, and additional sampling of AGMs from west of India (e.g., Pakistan, Iran, the Arabian Peninsula) will also be informative. Finally, this study is based on the analysis of a single marker (COI) because this is all that is presently available from published sources but we note that the application of new molecular markers such as single nucleotide polymorphisms to newly collected mussel samples will greatly advance our understanding of the AGM genetic discontinuity and its age, and help test its geographical location and its nature (e.g., a steep/shallow cline or a stepped cline).

show abstract

Section: Introductionmentioning

confidence: 99%

Phylogeography of the Asian green mussel, Perna viridis: pronounced regional genetic differentiation is explained by major freshwater input into the Bay of Bengal

Gardner

Patterson

2023

Front. Mar. Sci.

View full text Add to dashboard Cite

show abstract

“…Herron et al (2022) pointed out that mesoscale eddies could drive surface freshwater from the northern BoB southward into the southern BoB, and freshwater flux in the southern BoB usually reaches its delayed peak in summer. Influenced by surface freshwater, mesoscale eddies in the BoB have a relatively complex vertical thermohaline structure with seasonal variations (Cui et al, 2022), and their transport of water mass is expected to play a significant role in the redistribution of surface freshwater (Cui et al, 2022;Herron et al, 2022;Mahadevan et al, 2016;Paul et al, 2021). On the other hand, Zhu et al (2022) revealed that in November 2016, the EICC transported low-salinity water from the northern BoB southward to east of Sri Lanka, and meanwhile, a cyclonic eddy developed east of Sri Lanka, moving southwestward and transporting the low-salinity water to the southern AS.…”

mentioning

confidence: 99%

“…In the northern BoB, with an excess of freshwater input, surface freshwater flux reaches its maximum in winter due to freshwater accumulation at the end of the wet summer monsoon season. Herron et al (2022) pointed out that mesoscale eddies could drive surface freshwater from the northern BoB southward into the southern BoB, and freshwater flux in the southern BoB usually reaches its delayed peak in summer. Influenced by surface freshwater, mesoscale eddies in the BoB have a relatively complex vertical thermohaline structure with seasonal variations (Cui et al, 2022), and their transport of water mass is expected to play a significant role in the redistribution of surface freshwater (Cui et al, 2022;Herron et al, 2022;Mahadevan et al, 2016;Paul et al, 2021).…”

mentioning

confidence: 99%

An Energetic Mesoscale Anticyclonic Eddy in the Southern Bay of Bengal in June 2020: A Case Study

Ye,

Zhou,

et al. 2023

JGR Oceans

View full text Add to dashboard Cite

The southern Bay of Bengal (BoB) is a region of rich mesoscale eddy activity that plays an important role in modulating water exchange between the BoB and the Arabian Sea. Although statistical surface characteristics of mesoscale eddies in the BoB have been sufficiently explored previously, most studies concentrated on the western and central BoB, but rarely in the southern BoB. In this study, an energetic mesoscale anticyclonic eddy (AE) was detected by long‐term mooring observations in the southern BoB during June 2020. The mooring observations revealed that the AE‐induced maximum temperature and salinity anomalies at 100 m were as large as 6.8 °C and 0.3 psu, respectively. The available Argo profiles showed that the AE‐induced salinity anomalies had a three‐layer vertical structure, with a positive anomaly (maximum 0.28 psu) deeper than 100 m and (maximum 0.72 psu) shallower than 40 m, and a negative anomaly (maximum ‐0.86 psu) between 40 m and 100 m, indicating that the AE could exert a significant effect on the redistribution of surface freshwater in the southern BoB. The AE formation was closely connected with remote forcing (equatorial Kelvin wave) and local processes (Rossby wave and local wind stress curl). Analysis of local energy conversion analysis demonstrated that baroclinic and barotropic instabilities, as well as wind stress work made comparable contributions to the generation of the AE. Given the frequent occurrence of the AEs to northwest of Sumatra, they could have significant effects on surface freshwater redistribution and regional ecosystem productivity in the southern BoB.

show abstract

Role of the dipole mode index in governing the freshwater content within the bay of bengal summer pycnocline

Bohman,

Gordon

2023

Deep Sea Research Part I: Oceanographic Research Papers

View full text Add to dashboard Cite

Freshwater transport by eddies within the Bay of Bengal's central axis

Cited by 4 publications

References 17 publications

Phylogeography of the Asian green mussel, Perna viridis: pronounced regional genetic differentiation is explained by major freshwater input into the Bay of Bengal

Phylogeography of the Asian green mussel, Perna viridis: pronounced regional genetic differentiation is explained by major freshwater input into the Bay of Bengal

An Energetic Mesoscale Anticyclonic Eddy in the Southern Bay of Bengal in June 2020: A Case Study

Role of the dipole mode index in governing the freshwater content within the bay of bengal summer pycnocline

Contact Info

Product

Resources

About