Augmentation of Water—Can Oceans Help?

Drones- Unmanned Aerial vehicles (UAVs)- have become more significant across the world for a wide range of commercial and terrestrial defense applications in recent years. The National Institute of Ocean Technology (NIOT)- Ministry of Earth Sciences (MOES)- is exploring UAVs with a specific focus on maritime applications. NIOT has customized a heavy lift category drone, operable in marine environments and capable of withstanding coastal wind conditions of up to 40 kmph. It can lift and carry an instrumentation payload of 10 kg, conduct ocean data collection, and even take seawater samplings. The 10 kg payload of the UAV might hold a Conductivity Temperature Depth (CTD) sensor, a programmable sea water sampler, and a multi-parameter sensor (MPS) for ocean data collections, and a Light Detection and Ranging (LiDAR) device integrated with a high frame rate camera system for coastal mapping and digital elevation model (DEM) developmental applications. The customized hexacopter UAV is capable of withstanding winds of up to 10 m/s and features a waterproof IPX7 thruster with a maximum thrust of 153 N per axis. The UAV system is also interfaced with a Global Positioning System (GPS), a barometric pressure sensor, a compass, a highly accurate gyroscope, a 15 MP surveillance camera, and an accelerometer sensor connected to a reliable cube orange flight controller module with a redundant 32-bit controller through a serial peripheral interface (SPI). The drone structure and frame is composed of carbon fiber composites to provide an excellent weight-to-strength ratio. This paper presents the outcomes of an initial field test, carried out to ensure the drone’s suitability for various marine applications with intended payloads ranging from 5 - 10 kg weight, including coastal demonstrations and ocean data collections performed at Nellore (Andra Pradesh) and Chennai (Tamil Nadu) coastal waters. Highlights A drone is customised to with stand elevated wind conditions of coastal regions Design is fully flexible meeting the ease of transport from one location to other Highly stable mechanical design to sustain winds of up to 45 KMPH Redundant flight control mechanism is evolved to assure fail safe operations of drone Drone built in with redundant GPS module to avoid scenario like NO Geo-reference at any time Design is type certified and UIN registered with DGCA - India

Both brackish water desalination and seawater desalination processes are well established and in common use around the globe to create new water supply sources. The farther the location of the source water from the ocean or seashore, the lower the salinity (TDS) of the water and the lower the osmotic pressure that needs to be overcome when desalinated water is produced. This is one of the major reasons that brackish desalination is often considered less costly than seawater desalination. A number of project considerations, however, indicate that seawater desalination can be beneficial and more cost-effective than brackish water desalination. To make a fair comparison, we need to properly compare all major aspects of both types of projects to define the best and most appropriate desalination technology. While brackish water has less feed water TDS, it is more challenging to dispose of the produced concentrate. Also, although brackish water desalination needs less energy to overcome osmotic pressure, it usually requires more energy to draw the water from the well than it takes to pump seawater from the open ocean intake. Another factor is that the temperature of the brackish well water may be lower than the temperature of ocean water, giving seawater desalination an advantage in energy demand. In comparing brackish to seawater desalination, these major aspects should be evaluated: (1) Locations of seawater and brackish water plants, relative to the major consumers of the desalinated water, (2) Transportation (pumping and disposal) costs of the feed water and produced water, (3) Potential colocation of a seawater plant with a large industrial user (e.g., power plant) of the seawater for cooling or other purposes, (4) Produced quality of brackish water and seawater desalination in terms of major minerals and emerging contaminants, (5) Sustainability of the water source: capacity and depth of the brackish water wells, as well as the type of soil. (6) Technical and economic aspects of produced concentrate disposal, (7) Permitting process costs for brackish and seawater desalination, and (8) The economics of both brackish and seawater desalination treatment processes: capital costs, operational and maintenance (O&M) costs, lifetime water cost, and total water cost (TWC). This paper discusses the major evaluation criteria and considerations involved in properly comparing the economic and technical aspects of brackish and seawater desalination to determine the more favorable desalination technology for a given desalination project.

Oceans continuously interact with the overlying atmosphere, which dynamically varies and significantly impacts the weather and climate. The data over the oceans is complex and time series observations are vital. The knowledge we acquire from the data collected will help us to manage in oceans long term. Recent developments in ocean observation platforms and the advancements in sensor technologies have paved the way for modern and reliable deep sea instrumented buoy systems that offer most suitable and dependable platforms for uninterrupted data collection and transmission of the data in real-time to the shore through satellite communication networks. Ocean Observation Systems, an operational programme of National Institute of Ocean Technology, Chennai, under Ministry of Earth Sciences, Govt. of India has been deploying and maintaining moored data buoys in Indian waters since 1997. The data, received in compressed numerical data packets, takes a reasonable amount of time to decipher, infer and uncover some of the potentially valuable information it contains. Hence, validation and analysis of the data for making decisions during natural hazards has become colossal and relatively complicated. The challenge is to develop a rugged mechanism the harnessing information technology to generate the information required for ocean sustenance, which warrants partnering with Information Technology. To modern societies, digital communications and information technologies have become fundamental and referred as "connected society."Scientific community expect data to accurately represent the phenomenon that was measured. The data collected over prolonged periods are of immense use for scientists, to carry out scientific analyses, and frame strategic policies. Today, precise electronics and high-performance computers have altered our expectations of scientific data management, much as it has altered the expectations for many other elements of society and we find portentous agreement with improved data management strategies. CORNEA – Centre for Ocean Realtime iNformation viEw and Archives is a high-end IT infrastructure built with computational and visual capabilities to bring significant benefits to ocean researchers. Large quantum of data received from buoys contain information about various parameters such as meteorlogical, oceanographic (surface and subsurface). Mining them for predictive analysis and tracking the history of sensors is a challenge. This stresses the need for automated mechanism to collage the information and present it on demand, minimizing the challenges faced retrieving the same through manual means. ADDRESS (ADvanced Data REception and AnalysiS System) is a software tool developed for visualization within the context of data and information, heuristic way of interpretation, analysis, automated quality control, reliable data reception and dissemination using modern software technologies, which are the linchpin to a successful Ocean Observation Programme driven in the Information Technology era. Further, the buoy data is disseminated to the global community through Global Telecommunication Systems (GTS). The data and metadata from Indian buoy programme is acclaimed by the global scientific community. Ocean Best Practices methodology recognized by "International Oceanographic Data and Information Exchange" (IODE) of the Intergovernmental Oceanographic Commission (IOC) - UNESCO, is adopted to achieve quality and consistency in observation.Data from Indian buoy programme is also portrayed in OceanOPS (formerly JCOMMOPS), the agency that establishes a common platform, coordinates within and amongst ocean observation communities across the globe. Apart from regional, data from collaborative projects such as OMNI-RAMA are exhibited through interactive webportals with wealth of data and information to the scientific community blending international efforts.The culmination of this paper reveals how technology, confined is standards and best practices deployed, transform the way the ocean data is accessed, utilized, augmented, and transformed into information and knowledge.

Indian Tsunami Warning System was established in 2006 by National Institute of Ocean Technology (NIOT), Chennai, Ministry of Earth Sciences, Government of India. It comprises of Data Buoys with Bottom Pressure Recorders in the deep seabed and Acoustic Tide Gauge Network in the coastal areas. This paper describes design and field trials of an Advance Tide Gauge for Tsunami monitoring applications in India. The Advanced Tide Gauge measures tide, stores the data in the internal memory and transmits the real-time data via satellite telemetry to Indian Tsunami Warning Centre, Hyderabad and NIOT. The novel system is designed using networked low power embedded controllers in master and slave configuration. The state of the art system works on the ultrasonic time of flight measurement principle. The system was installed at Ennore Port, east coast of India on September 2007. Its performance was tested on September 12, 2007 with earth quake of magnitude 8.4 off Java coast.

The National Institute of Ocean Technology (NIOT), an autonomous organization under the Ministry of Earth Sciences, government of India, is engaged in developing and installing systems for tsunami detection and reporting. This involves high-precision bottom pressure recorders (BPRs) installed on the ocean floor, which can detect water level changes in the order of a few centimeters. Data are logged and recorded subsea by instruments located close to the BPRs. The detection of abnormal changes in the water level is required for detecting a tsunami event. This paper describes algorithms incorporated in most BPRs for detecting a tsunami by predictive methods such as Newton’s Extrapolation and Kalman predictor techniques. The most widely used tsunami detection algorithm is based on Newton’s extrapolation. The tsunami detection technique based on the Kalman prediction algorithm developed by NIOT can be an alternative for the existing technique. This paper describes both the algorithms and analyzes their effectiveness during tsunami event detection using MATLAB software. It is found that the Kalman algorithm has a better detection performance over the Newton extrapolation technique for tsunami wave amplitudes up to 300 mm. The Newton extrapolation technique has a better detection performance for tsunami wave duration of less than 10 min. For tsunami wave durations greater than 10 min, the Kalman algorithm has a better detection performance. As the wave durations of most of the recorded tsunamis are greater than 10 min, the Kalman algorithm could be a viable substitute for tsunami detection.

With a large coastline of approximately 7600 km surrounded by two major ocean basins on both sides of peninsular India as Bay of Bengal and Arabian Sea, drained by major river basins from Himalayas, there are multidimensional requirement of underwater technologies to cater the country's demand. With increased thrust on underwater technology in India during the past 15 years, it is imperative to put forth India's development in the frontier area of underwater technologies. Under the Ministry of Earth Sciences, Government of India, National Institute of Ocean Technology (NIOT) is leading the frontier areas of underwater technologies. The Institutes like Central Mechanical Engineering Research Institute and Indian Institute of Technologies are also contributing in a minor way. Under International Seabed Authority (ISA) regulations, Government of India registered as a contractor on 17th August 1987. India was allocated 150,000 sq. km area in Central Indian Ocean Basin for exploration of manganese nodules. After detailed exploration, 50% of this area has been relinquished to the ISA. While other Institutes in India are responsible for metal extraction, NIOT is responsible for developing technology for mining of manganese nodules from the deep seabed. To harness the non-renewable resources ranging from placer deposits at water depth of 100 m, gas hydrates at 1000 m, hydrothermal sulphides at 3000 m to polymetallic nodules at 5400 m water depth, various technologies were developed and proven in the field. To cater to the disaster management, range of observation systems, drifters and seafloor based observations are being developed and data collection and dissemination is in place. This paper deals with the achievements in the development of underwater vehicles and systems during the past 15 years in India in the civilian front. The major technologies developed, like the Deep sea crawler (512 m) for mining of manganese nodules, In-situ soil tester (5462 m) for measurement of in-situ soil property on the sea bed, Work Class Remotely Operated Vehicle (5289 m) for general purpose, including assistance in nodule mining, Autonomous Underwater Vehicle (200 m) for shallow water and operation in polar regions, being developed, and drifter buoys for collection of ocean data are explained in detail. The challenges involved in design, development, testing and issues faced during the sea trials of the various systems and lessons learnt are explained in this paper.

National Institute of Ocean Technology (NIOT), under the Ministry of Earth Sciences, along with IEEE OES and OSIs, conducts a national-level competition for students pursuing engineering degree to visualize and design an autonomous underwater vehicle. The conceptual basis for Student Autonomous underwater Vehicle (SAVe) is a highly mobile autonomous underwater vehicle (AUV) to be built based on engineering principles. This innovative initiative was launched in 2011 and so far NIOT had received 17,473 website hits, 257 registrations were made and 127 teams had submitted their Preliminary Design Reports (PDR) and 60 teams made oral presentation of Conceptual Design Reports (CDR) to improve their presentation and handle question and answer skills; 28 teams participated in the final competition and demonstrated their working and engineered AUVs at swimming pool. Most of the teams used 4–5 thruster configurations to have 6 DOF controlled by mostly Inertial Measurement Unit (IMU) interfaced with control unit (CPU) and powered by commercial LiPo battery packs. Till now, 3 teams had participated in International competition held at AUVSI foundation San Diego, USA and totally 8 prototypes of AUVs were developed by engineering students in India since year 2011. The aim of this competition was to involve young engineering students on the new frontiers of ocean technology and kindle their innovative thinking in this unexplored area of ocean environment and observation. The most common configuration of the student AUVs is that the linear dimensions of the AUVs are less than 1.5 m in length and weight is less than 35 kgs. The AUV design is a modular hydrodynamic hull structure and made up of acrylic material; mounted on Aluminium metallic frames. Many teams came up with modular thruster mounting frames which could help position the thrusters for good attitude control and this proved good stability of the vehicle against unwanted roll and pitch. All the teams were suggested to use maximum of 4 number of thrusters (for 6 degrees of freedom) to optimize the AUVs operation for considerable maneuverability with good energy efficiency and high endurance. Almost all the student AUVs get power supply from Lithium-Polymer (Li-Po) batteries with either 18.5 V or 11.1 V DC input to provide supply for the 19.1 V DC Thrusters and 12 V Mother Board. One of the most common features of the teams was Arduino microcontroller for controlling the thrusters interfaced with CPU. CPU configurations and capabilities of the teams processor speed varied from 1.6GHz to 2.1GHzsupported by 1GB or 2GB RAM. In fact, almost all the teams learned to use good quality web cameras for the underwater vision and image processing by placing them in sealed chambers. All the AUVs used face O-rings for the hulls for good sealing effect as well as for faster assembly and disassembly. Water resistant connectors were used to connect the AUV to supportive systems. The competition received overwhelming response from different institutions for which IEEE has come forward to extend financial support. The Office of Naval Research (ONR) also has shown interest to provide support for the competition to improve the awareness as well as encourage students in the field of underwater technologies.

ABSTRACTOcean–atmosphere interactions in the North Indian Ocean play a vital role in the onset, progression and withdrawal of the Indian monsoon. This paper describes the Ocean Observation System (OOS), an operational observational programme of the Earth System Science Organization and the National Institute of Ocean Technology (ESSO-NIOT) under India’s Ministry of Earth Sciences (MoES). Since 1997 it has provided oceanographic and surface meteorological data in real time for weather forecasting, climate research and several other applications. The programme focuses on understanding the phenomenon of the mean seasonal cycle of the Indian monsoon, the intra-seasonal to intra-decadal oscillations of air–sea interactions, trends that are related to tropical cyclones and the annual cycle balance in the exchange of waters between the two limbs of North Indian Ocean, i.e. the Arabian Sea and the Bay of Bengal. In situ observations are also used to develop, initialise and validate regional forecast models that provide high resolution data. There is also a growing need to understand the spatial phenomenon of oceans using satellite observations, wherein the quality of data needs to be validated and verified carefully. This paper also provides an overview of the scientific and societal impact of the Indian moored buoy network over two decades of operation.

The response of the shoreline to natural interfaces like creeks, estuaries, bays and engineering installations such as ports, harbours, groins, breakwaters etc., is of great significance to sustainable shoreline management as it is often observed that these interfaces / structures play a major role in altering the shoreline causing erosion and accretion largely due to their intervention with movement of alongshore sediments. Long term evaluation of the performance of these structures and the corresponding shoreline response is essential to understand the effects on the shoreline and for planning mitigation measures for management of adverse impacts. National Institute of Ocean Technology (NIOT) a Research and Development organization under the Ministry of Earth Sciences (Government of India) had taken an initiative of assessing the effects of various coastal structures on the shoreline along the coast of India. The aim of this study was to assess the impacts of coastal structures on the shoreline behaviour and thereby enable designing and implementation of environmentally friendly coastal infrastructure. This paper discusses the various phases of the study carried out along the coast of Tamilnadu state of India for evaluating the effects of various engineering structures. The coastline from Pulicat in the North to Neerody in the South, stretching across 1076km was covered as part of the study and 260 manmade structures were mapped. Potential sites were identified and behaviour of shoreline was simulated using numerical models which were calibrated using long term field data. The calibrated model was used for evaluating alternative options for shoreline management at select sites for mitigating the impacts of erosion / accretion caused by the structures. The entire work carried out was compiled and published as part of an atlas titled, Digital Information on Shore System Effects due to Manmade Interventions and Natural Alterations by Technological Evaluation (DISSEMINATE).

In recent years, aerial drones, or unmanned aerial vehicles (UAVs), have significantly expanded across industries such as environmental monitoring, search and rescue, video surveillance, precision agriculture, and coastal applications. The National Institute of Ocean Technology (NIOT), Ministry of Earth Sciences, has developed and customized a 22 kg heavy lift hexacopter drone specifically for marine and atmospheric applications. This UAV is designed for seawater sampling, oceanographic data collection, and coastal topography mapping, equipped with conductivity, temperature, and depth (CTD) sensors, multi-parameter sensors, an automatic seawater sampler, and light detection and ranging (LiDAR) technology. The drone is designed using a reliable Cube Orange flight controller, dual inertial measurement units (IMUs), dual global positioning system (GPS) modules, a dual radio frequency (RF) communication system, and 6 X8 Hobbywing rotors, supporting up to 10 kg of payload with a flight endurance of 30 min. Computational fluid dynamics (CFD) simulations were carried out using SolidWorks® 2024 flow simulation to analyze aerodynamic performance. Transient propeller-induced flow (PIF) studies were performed under varying headwind and crosswind velocities (0–10 m/s). The results show that yaw and roll deviations reached up to 12° and 35°, respectively, under crosswind gusts, and power consumption increased by 23 % in 8 m/s wind conditions, highlighting the effects of coastal wind dynamics on flight stability. These findings are validated using actuator disk theory and further verified by field tests. This study provides valuable insights into the aerodynamic behavior, stability, and energy demands of UAVs in dynamic marine environments, supporting the development of reliable drone-based platforms for sustainable coastal monitoring, oceanographic surveying, and environmental data acquisition.

The session on ocean best practices was held as part of UN Decade of Ocean Science for sustainable development (2021-2030) on 10thJanuary 2020.The meeting was attended by 75 Participants from 19Countries viz India, USA, Tunisia, Australia, Congo, Sri Lanka, Bangladesh, Cameroon, Tanzania, Maldives, France, UK, Russia, Saudi Arabia, Australia, Kuwait Indoos, Fugro (Industry)participated in the workshop. A List of participants is attached as Annexure.

Coastal erosion and flooding are serious threats across many coastal areas. They become globally more severe due to human-induced changes and accelerated sea-level rise. A significant proportion of beaches are undergoing long-term chronic erosion globally and on the Indian coast that leads to the loss of land and degradation of habitats. Several approaches have been attempted to control erosion and protect the coastal areas by adopting a hard coastal defence structure in response to these threats. Ministry of Earth Sciences through National Centre for Coastal Research (NCCR) and National Institute of Ocean Technology have devised nature-based solutions for the protection and restoration of beach. Here, we describe two recent beach protection and restoration schemes that use non-traditional soft approaches to prevent erosion and restore beaches. A detailed description of the environmental conditions at the site, implemented schemes and the morphological evolution are discussed. Both sites show significant growth in beach width and volume post implementation, contributing to socioeconomic development. Similar strategies can be adopted and implemented at other sites that are undergoing chronic erosion.

Heat recovery from sulphuric acid plants for seawater desalination

Multi-effect still for hybrid solar/fossil desalination of sea- and brackish water

The article describes the analysis and design of an optimum mooring system for the given spar configuration. National Institute of Ocean Technology (NIOT), Chennai has studied various configurations of floating platform and has designed and tested scaled down models of Semi-submersible and Spar based floating platform for accommodating Low Temperature Thermal Desalination (LTTD) plant. The Spar platform is to be permanently moored at 1000 m of water depth. The mooring configuration is very critical in the overall operation of the system. Hence a detailed study on this was carried out taking care of the nonlinearities of external forces induced in the system. Low frequency motions in surge, sway and yaw are excited by second order, nonlinear coupled effects between the wave and the Spar. The forces induced in the moorings are as well nonlinear due to nonlinear characteristics of the mooring material. The nonlinear mooring behavior characteristics and its effect on the platform motion discussed in the article, were carried out in potential/diffraction commercial simulation tool MOSES. The crucial parameters for the design including length, material, and mooring pretension were arrived from the simulation.KeywordsSparMooringLTTDDiffraction