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Latha, G.
- Signatures of very Severe Cyclonic Storm Phailin in Met-Ocean Parameters Observed by Moored Buoy Network in the Bay of Bengal
Abstract Views :269 |
PDF Views:121
Authors
R. Venkatesan
1,
Simi Mathew
1,
J. Vimala
1,
G. Latha
1,
M. Arul Muthiah
1,
S. Ramasundaram
1,
R. Sundar
1,
R. Lavanya
1,
M. A. Atmanand
1
Affiliations
1 National Institute of Ocean Technology, Velachery–Tambaram Main Road, Pallikaranai P.O., Chennai 600 100, IN
1 National Institute of Ocean Technology, Velachery–Tambaram Main Road, Pallikaranai P.O., Chennai 600 100, IN
Source
Current Science, Vol 107, No 4 (2014), Pagination: 589-595Abstract
The moored buoy network deployed in the Bay of Bengal played a critical role in the collection and transmission of surface meteorological and oceanographic conditions in real time through satellite telemetry, enabling constant monitoring of the cyclone Phailin. It is the first report of in situ timeseries measurement of a very low pressure taken during cyclones in the northern Indian Ocean. The BD10 buoy recorded a minimum atmospheric pressure of 920 hPa, which happened to be within the eye of the cyclone. This article presents an account of important changes that were observed in the surface meteorological and oceanographic parameters under the influence of the very severe cyclonic storm Phailin. An attempt has been made to understand the role of stratification in intensifying the cyclone Phailin in comparison with the cyclone Lehar which weakened in the ocean itself, based on subsurface data from the moored buoys which were on the track of the respective cyclones. Both the cyclones traversed across the Bay of Bengal in a similar way and the buoys were very close to the cyclone track withstood the rough sea conditions during the storms with their specially designed body. The BD09 buoy which happened to be on the right side of the track of cyclone Phailin moved in a circular path as a result of the inertial oscillation forced by the strong cyclonic winds.Keywords
Cyclonic Storm, Met-Ocean Parameters, Moored Buoy, Real-Time Observations.Full Text
- Observed Warming of Sea Surface Temperature in Response to Tropical Cyclone Thane in the Bay of Bengal
Abstract Views :282 |
PDF Views:92
Authors
Affiliations
1 National Institute of Ocean Technology, Pallikaranai P.O., Chennai 600 100, IN
2 Anna University, Guindy Campus, Chennai 600 025, IN
3 International CLIVAR Monsoon Project Office, Indian Institute of Tropical Meteorology, Pashan Road, Pune 411 008, IN
4 National Centre for Antarctic and Ocean Research, Headland Sada, Vasco-da-Gamma, Goa 403 804, IN
1 National Institute of Ocean Technology, Pallikaranai P.O., Chennai 600 100, IN
2 Anna University, Guindy Campus, Chennai 600 025, IN
3 International CLIVAR Monsoon Project Office, Indian Institute of Tropical Meteorology, Pashan Road, Pune 411 008, IN
4 National Centre for Antarctic and Ocean Research, Headland Sada, Vasco-da-Gamma, Goa 403 804, IN
Source
Current Science, Vol 114, No 07 (2018), Pagination: 1407-1413Abstract
An unusual near-surface warming was seen in observations from a moored buoy BD11 at 14°N/83°E, and a nearby Argo profiling float in the Bay of Bengal, during the passage of tropical cyclone Thane, during 25–31 December 2011. The cyclone induced a warming of sea surface temperature (SST) by 0.6°C to the right of the track. Heat budget analysis based on moored observations and satellite data rules out the role of horizontal advection and net heat flux in warming the surface layer. We find that vertical mixing/entrainment in response to the cyclone, in conjunction with a pre-storm temperature inversion (subsurface ocean warmer than SST) led to the observed warming. Pre-storm and post-storm salinity and temperature profiles from an Argo float close to the mooring BD11 have higher vertical resolution than the moored data; they suggest vertical mixing of the upper 70 m of the water column. The moored observations show that the thermal inversion, erased by storm-induced mixing, reappears in a few days.Keywords
Bay of Bengal, Cyclone, OMNI Buoy, SST.Full Text
References
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- Source Localization in Shallow Waters using an Acoustic Vector Sensor Array
Abstract Views :240 |
PDF Views:86
Authors
Affiliations
1 National Institute of Ocean Technology, Ministry of Earth Sciences, Chennai 600 100, IN
1 National Institute of Ocean Technology, Ministry of Earth Sciences, Chennai 600 100, IN
Source
Current Science, Vol 118, No 11 (2020), Pagination: 1707-1711Abstract
The objective of this article is to present the work carried out on source localization in the open sea using a Vector Sensor Array (VSA) with three elements, developed by the National Institute of Ocean Technology. In order to ascertain the performance of the VSA in the open sea, first a known source transmission– reception experiment was conducted. After completion of measurements at sea, the VSA was maintained in the mooring at the same location, for collection of ambient noise data. The results obtained from the data analysis demonstrate a fairly good performance of VSA in underwater source localization.Keywords
Acoustics, Beamforming, Direction of Arrival Estimation, Sensors, Source Localization.Full Text
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