Buoy electrical specifica�ons: ● 3 x Li-ion cells in parallel, 3.7 V x 2500 mA each cell, resul�ng in 7500 mA (buoy would be able to transmit about 15 days without sunlight) ● 4 x solar panel 5 V, 200 mA, 1 W. ● Scho�ky diodes, small Li-ion charger and electronic voltage step-up regulator to supply 7 V to Spot Trace GPS Tracker. ● 4 x lithium regular 1.5 V ba�eries for backup in case of electronic or solar power supply failure. References Tonini MH et al. (2013). A numerical study of gyres, thermal fronts and seasonal circula�on in austral semi-enclosed gulfs. Con�nental Shelf Research, 65, 97-110. Acknowledgments The construc�on of the buoys was part of the projects SAOCOM OCÉANO-09, PADI Founda�on N° 32625, PIP - 11220150100602CO and PICT - 2018-00870.
Figure 4 - Landsat OLI image from April 2021 showing the main circula�on of the Nuevo Gulf. Source: h�ps://oceancolor.gsfc.nasa.gov/gallery/748/.
Research communica�ons Oil spill detec�on using SAR data: A case study in the Gulf of Paria, Trinidad Shaazia Mohammed TrinidadandTobago. Alumnusprofile:https://nf-pogo-alumniningi.org/profile/smohamm/
Introduc�on rinidad and Tobago is one of the largest oil and natural gas producers in the Caribbean region. Emerging approximately 113 years ago, this industry has been the main contributor to the country’s economy [1]. Most discoveries span the southern part of Trinidad, promo�ng the construc�on of both offshore and onshore infrastructure. Recently, however, the nega�ve impact of oil has been rearing its ugly head. A 2019 newspaper ar�cle reported 377 oil spills occurring between 2015 - 2018, some of which are related to accidental discharges from boats [2]. Nega�ve impacts of oil spills on the marine environment are well documented by scien�fic research. For developing countries such as Trinidad and Tobago, it is a far-reaching socio-economic problem and can affect the economy, marine ecosystem and the human food chain. Accidental discharges (big or small) pose a constant threat, and their increased frequency should be considered equivalent to other sources of pollu�on. Consequently, this has led to the need for an increased monitoring of the extent, loca�on and es�ma�on of these spills [3]. Remote sensing technology is an effec�ve tool and has been extensively used for this purpose. The provision of freely accessible data allows for informa�on to be collected over large areas, enabling a more effec�ve response and deployment of resources. Numerous studies have found the Sen�nel-1 Synthe�c Aperture Radar (SAR) sensor to be suitable in detec�ng marine oil spills [4]. Its imaging capability to detect a spill either day or night and under all weather condi�ons ensures its usefulness in countries heavily impacted by the Inter-Tropical Convergence Zone (ITCZ) bands. This ac�ve microwave sensor has the ability to capture two dimensional (2D) images. The range of brightness reproduced on the captured image represents
Figure 1 - Structure of the data analysis.
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the proper�es of the target surface [5]. The detec�on of a poten�al oil spill on a SAR image pivots on the fact that an oil film on the sea surface will reduce the effects of short gravity and capillary waves [6]. This creates a less rough sea surface and thus diminishes the amplitude and intensity of the backsca�ering signal. The outcome results in the forma�on of dark patches in contrast with brighter surrounding oil free ocean. It should be noted spill thickness is not detectable by the sensor. However, for an oil spill to be detected on a SAR image the minimum thickness must be 1μm [3, 7]. Globally, numerous studies on the use of SAR data for spill detec�on have been inves�gated. A spill occurring on 7 August 2021 in the Gulf-of-Paria (GoP), Trinidad was found to be linked to a faulty 12-inch crude pipeline near the Pointe-a-Pierre harbour [8]. In situ observa�ons indicated the oil spill to be in the vicinity of Claxton Bay. At that �me, the spill covered an es�mated 2.35 km from the refinery but the extent and volume of the oil spill was s�ll being inves�gated. With limited research on the use of SAR data to assist with disaster response for the waters surrounding Trinidad and Tobago, this study aims the
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