Seasonal and spatial variations in spice generation in the South Indian Ocean salinity maxima
Spiciness anomalies generated in the salinity maxima region are important for several atmospheric and oceanic factors as they move along the geostrophic pathways towards the equator and resurface. Subduction and injection mechanisms are responsible for the spiciness generation in the South Indian Oc...
| Main Authors: | , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
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2024
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| Online Access: | https://hdl.handle.net/10356/174098 https://publons.com/wos-op/publon/52209460/ |
| _version_ | 1826118329763364864 |
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| author | Kaundal, Madhu Raju, Nadimpalli Jithendra Samanta, Dhrubajyoti Dash, Mihir Kumar |
| author2 | Earth Observatory of Singapore |
| author_facet | Earth Observatory of Singapore Kaundal, Madhu Raju, Nadimpalli Jithendra Samanta, Dhrubajyoti Dash, Mihir Kumar |
| author_sort | Kaundal, Madhu |
| collection | NTU |
| description | Spiciness anomalies generated in the salinity maxima region are important for several atmospheric and oceanic factors as they move along the geostrophic pathways towards the equator and resurface. Subduction and injection mechanisms are responsible for the spiciness generation in the South Indian Ocean (SIO) salinity maxima region. Using ECCO data from 1992 to 2017, here we study monthly variations of spiciness associated with both of these mechanisms in the SIO salinity maxima region. Using a Lagrangian approach, we estimated the monthly evolution of the subduction rate. A maximum subduction rate of 35–38 m/mon occurs during September and consequently decreases towards the end of the year. The effective subduction rate in the salinity maxima region shows the dominance of temporal induction (mixed layer tendency) term, with a sharp gradient in total subduction rate along the 30∘S associated with large mixed layer depth variation. Further, a high Turner angle (> 66∘) to the south of 30∘S confirms the generation of spiciness by injection mechanism. We found that the decrease in mixed layer salt (MLS) coincides with the increase in salinity below the mixed layer. To explore the significance of MLS changes in spiciness generation, we further addressed the monthly evolution of spiciness through MLS budget. Our results suggest that the entrainment and meridional advection terms are key to monthly variations in MLS changes and thus the spiciness. |
| first_indexed | 2024-10-01T04:41:56Z |
| format | Journal Article |
| id | ntu-10356/174098 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T04:41:56Z |
| publishDate | 2024 |
| record_format | dspace |
| spelling | ntu-10356/1740982024-03-18T04:57:04Z Seasonal and spatial variations in spice generation in the South Indian Ocean salinity maxima Kaundal, Madhu Raju, Nadimpalli Jithendra Samanta, Dhrubajyoti Dash, Mihir Kumar Earth Observatory of Singapore Earth and Environmental Sciences Spiciness Subduction Spiciness anomalies generated in the salinity maxima region are important for several atmospheric and oceanic factors as they move along the geostrophic pathways towards the equator and resurface. Subduction and injection mechanisms are responsible for the spiciness generation in the South Indian Ocean (SIO) salinity maxima region. Using ECCO data from 1992 to 2017, here we study monthly variations of spiciness associated with both of these mechanisms in the SIO salinity maxima region. Using a Lagrangian approach, we estimated the monthly evolution of the subduction rate. A maximum subduction rate of 35–38 m/mon occurs during September and consequently decreases towards the end of the year. The effective subduction rate in the salinity maxima region shows the dominance of temporal induction (mixed layer tendency) term, with a sharp gradient in total subduction rate along the 30∘S associated with large mixed layer depth variation. Further, a high Turner angle (> 66∘) to the south of 30∘S confirms the generation of spiciness by injection mechanism. We found that the decrease in mixed layer salt (MLS) coincides with the increase in salinity below the mixed layer. To explore the significance of MLS changes in spiciness generation, we further addressed the monthly evolution of spiciness through MLS budget. Our results suggest that the entrainment and meridional advection terms are key to monthly variations in MLS changes and thus the spiciness. Ministry of Education (MOE) National Research Foundation (NRF) DS was funded by the Ministry of Education Academic Research Fund MOE2019-T3-1-004, the National Research Foundation Singapore, and the Singapore Ministry of Education, under the Research Centres of Excellence initiative. This work comprises Earth Observatory of Singapore contribution no. 434. MKD was funded by the climate change project of Department of Science and Technology, Govt. of India. 2024-03-18T04:57:04Z 2024-03-18T04:57:04Z 2022 Journal Article Kaundal, M., Raju, N. J., Samanta, D. & Dash, M. K. (2022). Seasonal and spatial variations in spice generation in the South Indian Ocean salinity maxima. Ocean Dynamics, 72, 313-323. https://dx.doi.org/10.1007/S10236-022-01502-2 1616-7341 https://hdl.handle.net/10356/174098 10.1007/S10236-022-01502-2 WOS:000782166300001 https://publons.com/wos-op/publon/52209460/ 72 313 323 en MOE2019-T3-1-004 Ocean Dynamics © 2022 Springer-Verlag GmbH Germany, part of Springer Nature. All rights reserved. |
| spellingShingle | Earth and Environmental Sciences Spiciness Subduction Kaundal, Madhu Raju, Nadimpalli Jithendra Samanta, Dhrubajyoti Dash, Mihir Kumar Seasonal and spatial variations in spice generation in the South Indian Ocean salinity maxima |
| title | Seasonal and spatial variations in spice generation in the South Indian Ocean salinity maxima |
| title_full | Seasonal and spatial variations in spice generation in the South Indian Ocean salinity maxima |
| title_fullStr | Seasonal and spatial variations in spice generation in the South Indian Ocean salinity maxima |
| title_full_unstemmed | Seasonal and spatial variations in spice generation in the South Indian Ocean salinity maxima |
| title_short | Seasonal and spatial variations in spice generation in the South Indian Ocean salinity maxima |
| title_sort | seasonal and spatial variations in spice generation in the south indian ocean salinity maxima |
| topic | Earth and Environmental Sciences Spiciness Subduction |
| url | https://hdl.handle.net/10356/174098 https://publons.com/wos-op/publon/52209460/ |
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