Seasonality of Stratification Along the Offshore Area of the Northern Bay of Bengal
One of the vital factors for understanding and investigating ocean dynamics is the stratification of the water column. Argo profiling floats for the period of January 2011 to September 2017 and World Ocean Data (WOD) for the same region were taken to comprehensively study temperature-salinity distribution from which to calculate the sigma-t (density). The average density increased sharply from around 20 m to 180 m depth. It is obvious that the northern Bay of Bengal (BoB) is much cooler than the southern bay. Additionally, the southern BoB is denser than the northern BoB. The strong seasonal cycle of temperature and salinity was noticed which eventually controls the comparatively fresher water in the north and saltier water to the south. Furthermore, the static stability parameter of the water column was used to understand the processes affecting the stratification. The more the water is stable, the more the stratification of water is observed. Vertical stability was undulated in the upper 200 m and between 300-500 m depth. It was also found to be varied with strong south-west monsoon and north-east monsoon. Summer monsoon showed much stable than the winter monsoon because of the river runoff. Perhaps, the less dense water floating in the surface in summer could create the layer much stratified by inhibiting the subsurface nutrient to come upward and the opposite pattern was seen in winter monsoon. In spring and fall, southern BoB stability was stronger than northern. The study revealed that both of the available open-source datasets are very useful and precise to each other.
Read moreShip Registration System of Bangladesh: An Assessment
Registration offers a flag to a vessel providing access to high sea and ports worldwide. Many countries pursued aggressive registration policy allowing non-citizens with flexible tax and fee structure resulting in a significant amount of revenue earning by becoming the desired destination for ship registration worldwide. Despite ample opportunities, Bangladesh could not tap the potentials of ship registry to boost up her economic growth through fleet expansion. This paper aims at identifying challenges of ship registration in Bangladesh and put forward strategies for their mitigation to get optimum output in the registration market. This study revealed a complicated ship registration process in Bangladesh relying on national register with nationality as a determining factor for registry resulting in sluggish growth of ship registration. The underlying causes are the rigid legal frame, inadequate institutional architecture, huge tax burden, insufficient incentive. Therefore, this study recommends flexibility in a legal frame to introduce hybrid registries, reformation of Mercantile Marine Office, automation of registration process, rationalization of the tax regime and investment facilitation through incentives.
Read moreWave Energy Harnessing for Marine Propulsion - An Approach Towards Energy Efficient Shipping
The quest for clean sources of energy is still too far from the challenge faced by the modern world of the 21st century. An increasing amount of industrialization is continuously resulting in a gradual depletion of fossil fuel and extensive damage to the environment. The shipping sector, one of the biggest and ever-expanding industries of the world, almost exclusively uses fossil fuels to meet its energy needs. Due to the nature of this industry, there is always availability of waves at sea which can be harnessed and utilized as a source of energy though it hasn’t been utilized yet in vast canvas. Wave energy can be considered as a robust form of energy and an effective alternative to fossil fuel if it can be properly harnessed. This study focused on how energy could be produced from ocean waves and could be used efficiently in the propulsion system. Methodology revealed here is basically to show the viability of the application of Wave Energy Converter (WEC) technologies in a vessel while at anchorage and port, since the application of WEC during sailing of a vessel hasn’t still been proved as an efficient option because of vessel size associated with additional drag resistance. Aim of this paper is to elucidate mathematically if the harnessing is possible at anchorage time and additionally describes the theoretical prospect of mass implementation possibility at the port to affirm energy-efficient shipping. The outcome of this research could lead to an energy efficient and economical propulsion system with the utilization of a renewable energy source as well as a reduction in carbon dioxide emissions.
Read morePrevention of Grounding at Mongla Port with Virtual AIS
About 90% of worldwide cargo transportation is performed by merchant ships. The trading is successfully completed only when the cargo is safely loaded, transported and safely delivered to the buyer. After loading vessels may navigate through channels, canals, rivers, bays, seas and oceans and carry the cargo to the destination. The navigation is done by ship’s officers with the help of maps, charts and various navigation equipment available onboard. Ship’s navigation is also helped from outside sources like the GPS satellites, communication satellites, lighthouses, light vessels, navigational buoys. By default, all systems must work perfectly otherwise ships may face trouble while underway. The Automatic Identification System (AIS) used by ships and ports for identification of ships. This can also be installed on light vessels and navigational buoys for identification with AIS equipment, RADAR (Radio Aid for Detection and Ranging) or ECDIS (Electronic Chart Display and Information System). Virtual AIS is a relatively new technology where no navigational buoys are placed on site but they can be detected by ships and this system will help the ships to navigate safely. Mongla Port is the second seaport of Bangladesh. It is situated in the Southern part of Khulna division and it is about 48 km south of Khulna city. Presently it has become a very busy port due to huge import of cement clinker, slag, gypsum, various fertilizers, coal, bulk edible oil, food grains, stone chips, heavy machinery and bulk LPG. Container and car carrier vessels also visit this port regularly. The introduction of Virtual AIS will help all the vessels to navigate safely throughout Pussur river, the risk of grounding will be minimized and hence there will not be any danger of oil pollution from grounded vessels and the ecological system of the Sundarbans will be preserved.
Read moreDoes Sea Surface Temperature Explain the Seasonal Variability of Chlorophyll in the Upper Indian Ocean?
Quantitative analyzes of chlorophyll concentration in relation to Sea Surface Temperature (SST) can explain the spatiotemporal distribution of phytoplankton in oceans. In this study, the response of chlorophyll in the Bay of Bengal (BoB) and the Arabian Sea (AS) to seasonal SST was investigated using remotely sensed Moderate Resolution Imaging Spectroradiometer (MODIS) data. MODIS SST data were validated with in-situ data derived from the World Ocean Database. Thus, satellite-based SST estimates were more reliable for BoB than that of AS. In general, SST was comparatively high in BoB; the lowest 27.88° C recorded in January and the highest 30.33° C in April. In contrast, maximum SST in AS was 29.82° C in May and minimum 26.66° C recorded in January. The chlorophyll concentration in BoB was minimum (0.31 mg m-3) in April and maximum (0.46 mg m-3) in September. While the chlorophyllin AS was minimum (0.34 mg m-3) in April and maximum (1.18 mg m-3) in September. These results suggest a significant negative association between SST and chlorophyll in BoB and AS that can explain 32% variability of chlorophyllin both areas. Other than SST, a large number of biotic and abiotic factors, such as nutrient availability, presence of sunlight, mixing layer depth, grazing etc. affect the seasonal variation of chlorophyll. Nevertheless, this study will provide useful information to understand the phytoplankton dynamics in tropical seas
Read moreShipbuilding: A Gateway for Bangladesh to Achieve Economic Solvency
Bangladesh has been ranked 41st among the world's largest economies in 2019 as well as become the second biggest economy in South Asia. As a maritime nation, the country focuses on prospects of Blue Economy and aspires to be a middle-income country by 2021 and developed economy by 2041. To achieve this goal the shipbuilding industry can be the perfect alternative. Being a nation next to the sea, she has a long heritage of building oceangoing ships. With the recent success of the shipbuilders of Bangladesh, it is crystal clear that this industry has more potentials to impact the national economy. The study was mainly a descriptive research. Data were mainly collected from secondary sources. Some primary data were also collected from experts and policymakers through unstructured interviews. The study revealed that Bangladesh has a great potentiality in this sector. Bangladesh is emerging as a shipbuilding nation. In the last decade by exporting more than a hundred ships, Bangladesh earned a lot of foreign currency. The shipbuilding industry of Bangladesh has a great scope in the international market for building small ocean-going vessel although there are some obstacles and challenges that are hindering the proper growth of this industry. The study provided valuable guidance for the government of Bangladesh to make a clear policy regarding the expansion of the shipbuilding industry to attain economic solvency. It is expected that this study would contribute to improving policy, further research and advance the frontier of the knowledge.
Read moreOcean Governance for Sustainable Maritime Development in the Bay of Bengal
The human civilisation is indebted to the oceans for serving mankind as a major source of food, minerals and energy linking economies around the world. The oceans serve as an engine for global economic growth and highways for seaborne international trade giving access to global markets. But there has been a growing appreciation that the world’s oceans require more caring attention and integrated response. There is a progressive degradation of ocean health caused by IUU fishing, marine pollution and unplanned coastal development. However, in recent years, few developing countries have looked to the ocean as a new economic frontier and developed growth policies based on the concept of the Blue Economy. It is aimed at enhancing livelihoods for the poor, creating employment opportunities and reducing poverty. A Blue Economy roadmap is essential to provide an integrated approach to ocean-based sustainable development, which brings together economy, environment and society being closely linked with the UN Sustainable Development Goals 2030 (SDGs). Making the transition to a Blue Economy would entail fundamental and systemic changes in the policyregulatory-management-governance framework using the tools of an ecosystem-based Marine Spatial Planning (MSP). Today the littoral countries of the Bay of Bengal are showing huge trends of economic development due to their increasing importance on the ocean-based economy. But our development patterns are often undermined and diminished due to lack of appropriate ocean governance measures whereas various policies are either poorly implemented or lacks supervision. So, a regionally integrated management and governance system is the demand of the day in order to ensure sustainable maritime development in the Bay of Bengal region. In this context, the paper endeavours to analyse how the Bay of Bengal region is responding to the challenges of ocean governance and harvest Blue Economy benefits from the ocean. In fact, the challenges are many, but a properly planned Blue Economy and Ocean Policy can bring to the developing countries of this region substantial benefits of economic and social development in the years ahead.
Read moreMapping and GIS Analysis of Small Water Reservoirs in the Hills of the Halda River Watershed
The aim of this research is to the discovery of small water reservoirs in the Halda river watershed, analysing their geometric and geographic parameters like area, neighbourhood distance, elevation wise distribution, tortuosity, perimeter and also mapping these small water reservoirs. Through this research work, a total of 593 reservoirs is identified and mapped. The total area of those reservoirs is 6,124,117 m2 (6.12 km2 ) which cover almost 0.36% of total Halda watershed area and 0.56% of upland (>20 m elevation) area. The average area of these reservoirs found around 10327 m2 . The minimum and maximum area of these small reservoirs found around 180 m2 and 115007 m2 respectively. The neighbourhood distance also calculated. The highest occurring distance among reservoirs is around 830 m. The maximum and minimum distance is around 3391 and 44 m respectively. The total number of the neighbourhood is found 1595 under 3400 m cut off distance. The average elevation is found 30.74 m. Elevation wise distribution shows that most of the reservoirs are located in the hill tracts of Halda river watershed which commonly known as upland area. Tortuosity of reservoirs is calculated. From the descriptive statistics, the average tortuosity of studied reservoirs is around 7. Most of the small reservoirs have 250 m to 500 m perimeters. Their average perimeter is calculated as 696.17 m. For the first time, the reservoir map and their relative neighbourhood graph of Halda river watershed are generated through this research.
Read moreDrivers of Revenue Generation in the Blue Economy of Bangladesh: A Case Study on the Chattogram Sea Port
Blue Economy is a blessing for an emerging economy like Bangladesh. After achieving a new maritime boundary, it becomes more significant for economic development utilising ocean resources. Considering this phenomenon, this paper aims to find out the drivers of revenues in the context of the Blue Economy of Bangladesh. The study has confined itself to the Chattogram Sea Port and its operations. Itis based on historical data ranges from 2009 to 2018. The methods of research analysis were descriptive statistical tools, tabular and graphical analysis. The study has found out that the Chattogram Sea Port (CSP) has been contributing to the Blue Economy of Bangladesh. The major drivers of revenue generation are living resources, minerals, energy and transport and trade at the seaports.CSP generates most of its revenues from the export-import, containersand vessel management. Expenditure control can also enhance the revenue of CSP. Proper planning and policies can expedite the growth of the Blue Economy in Bangladesh. The effort should be balanced between proper planning and effective execution.
Read moreMaximum Sustainable Yield Estimate for Tiger Shrimp, Penaeus monodon off Bangladesh Coast Using Trawl Catch Log
Tiger shrimp, Penaeus monodon is the most economically important penaeid shrimp in Bangladesh for both culture and capture fishery. This study reveals an analytical stock assessment of tiger shrimp in Bangladesh marine waters after three decades of the inclusive survey. A time series of annual Catch Per Unit Effort (CPUE) was derived from commercial logbook data during the period from 1986 to 2017 and used as a tuning series for a Schaefer biomass model through MS-Excel and CMSY/BSM interfaces. The standing stock and harvest rate were estimated to be around 1250 t and 23% respectively. The estimated Maximum Sustainable Yield (MSY) reference points with 95% confidence interval are optimum biomass BMSY2360 t (1670-3320 t) and optimum fishing mortality Fmsy = 22% (16-31%). The average annual catch of last two decades 308 t, below estimated MSY of 527 t (388-717 t). Overall the stock is estimated to be at alarming state despite average annual catch lower than MSY for the last two decades. The enigma for this loophole likely to be lies indiscriminate exploitation of postlarvae (PL) from nature for coastal aquaculture and an extensive collection of brood shrimp for shrimp hatchery broodstock.
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