Implementation of marine environmental distance monitoring

Earth is rightfully called the Ocean Planet – more than 70 percent of the surface is covered by sea. Despite being such an essential part of life, more than 80 percent of the world’s oceans are unmapped. According to the American Museum of Natural History in New York, merely 10 to 15 percent of the seafloor has been mapped with accuracy, which means we know less about the seafloor than the surface of Mars.

However, technologies of sea exploration are changing fast. The dark, high-pressure conditions of the ocean depths that were once made oceanography research impossible are now being explored with innovative technologies. Besides scientific exploration, the study and understanding of the ocean is also important for the shipping industry. The data received from the oceans is required for meteorology such as predicting weather and sea conditions, which is vital for ships in planning courses and taking necessary precautions.

There are several tools commonly used in monitoring the marine environment:

Acoustic Doppler Current Profiler (ADCP): An ADCP is a device that utilizes sound waves to measure the speed and direction of currents throughout the water column. Understanding how water in the ocean moves provides essential information about the biological, chemical, and physical properties of the ocean. The ADCP uses the Doppler effect by transmitting “pings” of sound using a sequence of consistent rapid pulses that ricochet off particles suspended in moving water and reflect back to the instrument. The instrument can be mounted directly on a stationary object like a mooring buoy or even directly on the seafloor. They can also be mounted to a moving vehicle, such as ships or unmanned underwater and surface vehicles. On large research vessels, the ADCP is permanently mounted on the bottom of the ship’s outer hull.

Drifters: Using this device, oceanographers can study global ocean currents and their effects. With recent advancements, drifters provide ocean circulation patterns in real-time. The “shallow water” drifter can be deployed from a ship or an airplane. Once it is floated, the transmitter starts sending data to the satellite, which further transmits it to receiving stations where the data is processed. Other sensors for surface temperature, wind, ocean color, pressure, and salinity may also be housed in the device to get more information from the sea.

Buoy System: Buoy is a floating instrumentation platform in the sea that can be used to collect information about the sea and environmental conditions. Surface buoy collects information such as sea-surface temperature, current speed, humidity, wave parameters, wind speed, and direction using various sensors. The data is sent to shore stations through satellite, which analyses the data and predicts sea-state for that particular area. In the case of the Tsunami Buoy System, there is a 4th component called Bottom Pressure Recorder (BPR), which is deployed at the ocean bottom and fitted with pressure sensor. The sensor measures pressure at the bottom and predict the height of the water above the seafloor.

SONAR: Sound Navigation and Ranging—SONAR is a technology which uses sound wave to find and identify objects in the water. Sound wave holds the advantage of attenuating less in water than electromagnetic waves. First used during World War-1, the technology has improved greatly with the development of digital computers in the 1960s which made plotting of sonar data much easier. SONAR is generally categorized as Active and Passive sonar. Active sonar transducers emit an acoustic signal and detect any object if a sound wave is reflected to the receiver. The same method is used to measure water depth at various locations. Passive sonar is primarily used to detect noise from submarines, ships or marine animal and is therefore particularly useful in naval operations.

Satellite Oceanography: Though the most important purpose of satellite is to establish communication from ocean to land, it also serves a vital role in ocean observing as well. Environmental satellites provide images of sea surface temperature which helps knowing water circulation patterns. Satellite also gives data of the color of the ocean (among other data) which helps oceanographers to determine the impact of floods along the coast and to detect algal blooms. In recent years, remote sensing technology has equipped satellites with altimetry (which measures sea surface height) and scatterometry (which measures wind speed and direction). Geosynchronous environmental satellites monitor the development of major storms, such as hurricanes and tornadoes. Satellite imagery maps also provide information on coral reefs, coastal habitats, and similar environments.

Autonomous Underwater Vehicle (AUV) Sentry: Sentry is an AUV capable of diving to depths of 3.7 miles (6,000 meters) without direct human control or connection to a ship and can remain submerged for up to 40 hours. Common missions for the vehicle involve surveying the seafloor to map features such as hydrothermal vents or deep-sea coral reefs, shipwrecks, and oil wells. Sentry carries a sonar mapping system that includes a high-resolution echo sounder capable of generating 3D models of the seafloor. It is also equipped with a high-resolution digital camera that provides scientists with immense data of the seafloor.

ROV or Remotely Operated Underwater Vehicle: ROV is an unoccupied vehicle similar to a robot. It is fitted with sensors and sampling tools to collect distinct types of data from the oceans. A network of cables is utilized to establish a connection between the operator and the remotely operated vehicle, which would enable the proper movement of the ROV. The ROV is well-equipped with modern technology and consists of a lighting system and a video camera to record a better subaquatic panorama and contribute to geology education and sea life learning.

Geographical Information System (GIS): A GIS is an unconventional tool for ocean exploration. It is neither a physical device nor a submersible technology that comes into direct contact with the water. A GIS cannot take us any deeper into the oceans, but it can take us further in terms of our understanding, because of the way it gathers and analyzes information. Given enough data, a GIS can create a virtual ocean inside of a computer. A GIS is comprised of three parts: spatial information, special software, and a computer. These components work together as a system to provide a digital platform for viewing and processing layers of spatial information. Because of its power and speed, GIS technology is doing most of the cartographic (map-making) work that, in the past, was laboriously done by hand on paper charts and maps. Normally CAD program is used for digitalizing map and survey plan.

Despite all of these technological advances, there is still so much more to learn and explore. It is difficult to predict what space and ocean exploration will look like in the future. However, it is no doubt that more exciting discoveries will be made and possibly benefit people in the long run. Unlocking the mysteries of ocean ecosystems can reveal new sources for medical drugs, food, energy resources, and others. Information from deep-ocean exploration can help predict earthquakes and tsunamis and help us understand how we are affecting and being affected by changes in the Earth’s environment. Ocean exploration will also improve ocean literacy and inspire young people to seek careers in science, technology, engineering, and mathematics.