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102-437: The underwater world is still mostly unknown. The main reason for it is the difficulty to gather information in situ, to experiment, and even to reach certain places. But the ocean nonetheless is of a crucial importance for scientists, as it covers about 71% of the planet. Knowledge of ocean currents is of crucial importance. In important scientific aspects, as the study of global warming, ocean currents are found to greatly affect

204-472: A World Heritage Site . A 2021 study following a 2014 loss of a container carrying printer cartridges calculated that some cartridges had dispersed at an average speed of between 6 cm and 13 cm per second. A 1997 accident of Tokio Express ship off the British coast resulted in loss of cargo container holding 5 million Lego pieces. Some of the pieces became valued among collectors who searched

306-636: A 10-day duty cycle. The Argo program is a collaborative partnership of more than 30 nations from all continents (most shown on the graphic map in this article) that maintains a global array and provides a dataset anyone can use to explore the ocean environment. Argo is a component of the Global Ocean Observing System (GOOS), and is coordinated by the Argo Steering Team, an international body of scientists and technical experts that meets once per year. The Argo data stream

408-628: A 2016 study of Aruba found that debris found the windward side of the island was predominantly marine debris from distant sources. In 2013, debris from six beaches in Korea was collected and analyzed: 56% was found to be "ocean-based" and 44% "land-based". In the 1987 Syringe Tide , medical waste washed ashore in New Jersey after having been blown from Fresh Kills Landfill . On the remote sub-Antarctic island of South Georgia , fishing-related debris, approximately 80% plastics, are responsible for

510-487: A company, and there were many unbranded objects. Not all anthropogenic artifacts placed in the oceans are harmful. Iron and concrete structures typically do little damage to the environment because they generally sink to the bottom and become immobile, and at shallow depths they can even provide scaffolding for artificial reefs . Ships and subway cars have been deliberately sunk for that purpose. Additionally, hermit crabs have been known to use pieces of beach litter as

612-608: A danger to navigation. For example, the US Army Corps of Engineers removes 90 tons of "drifting material" from San Francisco Bay every month. The Corps has been doing this work since 1942, when a seaplane carrying Admiral Chester W. Nimitz collided with a piece of floating debris and sank, costing the life of its pilot. The Ocean cleanup has also created a vessel for cleaning up riverine debris, called Interceptor . Once debris becomes "beach litter", collection by hand and specialized beach-cleaning machines are used to gather

714-424: A depth of 2000 metres (pressure of 2000 decibars) the temperature might be 2°C and the salinity 34.58 parts per thousand. Thus, including the effect of pressure (water is slightly compressible) the density of sea-water is about 1.0369 g/cm . The change in density divided by the deep density is 0.0109. The float has to match these densities if it is to reach 2000 metres depth and then rise to

816-812: A float transmits a profile it is quickly converted to a format that can be inserted on the Global Telecommunications System (GTS). The GTS is operated by the World Meteorological Organisation , or WMO, specifically for the purpose of sharing data needed for weather forecasting. Thus all nations who are members of the WMO receive all Argo profiles within a few hours of the acquisition of the profile. Data are also made available through ftp and WWW access via two Argo Global Data Centres (or GDACs), one in France and one in

918-581: A global array of temperature, salinity and pressure of the top 2000m of the ocean. It uses over 3000 floats, some of which use RAFOS for underwater geolocation; most simply use the Global Positioning System (GPS) to obtain a position when surfacing every 10 days. This project has greatly contributed to the scientific community and has issued many data that has since been used for ocean parameters cartography and Global change analysis. Many results have been achieved thanks to these floats, on

1020-512: A layer developed by the Argo Technical Coordinator. Argo is now the dominant source of information about the climatic state of the oceans and is being widely used in many publications as seen in the diagram opposite. Topics addressed include air-sea interaction, ocean currents , interannual variability, El Niño , mesoscale eddies , water mass properties and transformation. Argo is also now permitting direct computations of

1122-402: A license – licensing is a provincial government responsibility. The Victoria-based non-profit Dead Boats Disposal Society notes that lack of enforcement means abandoned boats are often left to sink, which increases the cleanup cost and compounds the environmental hazard (due to seepage of fuel, oil, plastics, and other pollutants). On the sea, the removal of artificial debris (i.e. plastics)

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1224-422: A microprocessor. The clock is essential in locating the float, since it is used as reference to calculate the time travel of the sound signals from the moored emitters. It is also useful to have the float work on schedule. The microprocessor controls all subsystems except the clock, and stores the collected data at a regular schedule. The satellite transmitter is used to send data packages to orbiting satellites after

1326-486: A much greater volume of the ocean to be sampled. Such measurements are important for developing a comprehensive understanding of the ocean, such as trends in heat content. The original plan advertised in the Argo prospectus called for a nearest-neighbour distance between floats, on average, of 3° latitude by 3° longitude. This allowed for higher resolution (in kilometres) at high latitudes, both north and south, and

1428-527: A new approach to analyzing global warming , reported in Eos in 2017. David Morrison reports that "[b]oth of these data sets show clear signatures of heat deposition in the ocean, from the temperature changes in the top 2 km of water and from the expansion of the ocean water due to heating. These two measures are less noisy than land and atmospheric temperatures." Argo and CERES data collected between 2005 and 2019 have been compared as independent measures of

1530-458: A patchwork of regulatory authorities (responsibility often differs for the ocean surface, the seabed, and the shore). For example, there are an estimated 1600 abandoned and derelict boats in the waters of British Columbia. In 2019 Canada's federal government passed legislation to make it illegal to abandon a vessel but enforcement is hampered because it is often difficult to determine who owns an abandoned boat since owners are not required to have

1632-465: A profiling float called Navis. A typical Argo float is a cylinder just over 1 metre long and 14 cm across with a hemispherical cap. Thus it has a minimum volume of about 16,600 cubic centimetres (cm ). At Ocean Station Papa in the Gulf of Alaska the temperature and salinity at the surface might be about 6°C and 32.55 parts per thousand giving a density of sea-water of 1.0256 g/cm . At

1734-555: A river or lake beach cleanup. [REDACTED] Media related to Marine debris at Wikimedia Commons Argo (oceanography) Argo is an international programme for researching the ocean. It uses profiling floats to observe temperature , salinity and currents . Recently it has observed bio-optical properties in the Earth's oceans. It has been operating since the early 2000s. The real-time data it provides support climate and oceanographic research. A special research interest

1836-404: A shell when they cannot find an actual seashell of the size they need. Many animals that live on or in the sea consume flotsam by mistake, as it often looks similar to their natural prey. Overall, 1288 marine species are known to ingest plastic debris, with fish making up the largest fraction. Bulky plastic debris may become permanently lodged in the digestive tracts of these animals, blocking

1938-526: A storm. The toys have since been found all over the world, providing a better understanding of ocean currents . Similar incidents have happened before, such as when Hansa Carrier dropped 21 containers (with one notably containing buoyant Nike shoes). In 2007, MSC Napoli beached in the English Channel , dropping hundreds of containers, most of which washed up on the Jurassic Coast ,

2040-413: A theoretical maximum depth of about 2700 m. The external ballast is suspended by a short piece of wire chosen for its resistance to saltwater corrosion. By dissolving it electrolytically the 1 kg ballast is released and the float returns to the surface. The electronics can be divided into four categories: a satellite transmitter used after surfacing, the set of sensors, a time reference clock, and

2142-515: Is a European Union directive committing EU member states to free inland and coastal waters from human influence. In the United Kingdom, the Marine and Coastal Access Act 2009 is designed to "ensure clean healthy, safe, productive and biologically diverse oceans and seas, by putting in place better systems for delivering sustainable development of marine and coastal environment". In 2019,

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2244-627: Is a global common , so negative externalities of marine debris are not usually experienced by the producer. In the 1950s, the importance of government intervention with marine pollution protocol was recognized at the First Conference on the Law of the Sea. Ocean dumping is controlled by international law , including: One of the earliest anti-dumping laws was Australia's Beaches, Fishing Grounds and Sea Routes Protection Act 1932 , which prohibited

2346-477: Is a file specific to 6 November 2012 and contains all profiles in a single NetCDF file for one ocean basin. The GDACs identify three ocean basins, Atlantic, Indian and Pacific. Thus three multi-profile files will carry every Argo profile acquired on that specific day. A user who wants to explore Argo data but lacks programming skills might like to download the Argo Global Marine Atlas which

2448-484: Is able to accurately track and send cleanup vessels to remove ghostnets. The GPS Tracker technology is being combined with satellite imagery increasing the ability to locate plastic trash and ghostnets in real time via satellite imagery which will greatly increase cleanup capacity and efficiency. Another issue is that removing marine debris from the ocean can potentially cause more harm than good. Cleaning up microplastics could also accidentally take out plankton, which are

2550-646: Is an easy-to-use utility that allows the creation of products based on Argo data such as the salinity section shown above, but also horizontal maps of ocean properties, time series at any location etc. This Atlas also carries an "update" button that allows data to be updated periodically. The Argo Global Marine Atlas is maintained at the Scripps Institution of Oceanography in La Jolla, California. Argo data can also be displayed in Google Earth with

2652-621: Is an organization aimed at reducing plastics pollution in the oceans, and was one of two organizations that recently researched the Great Pacific Garbage Patch . Heal the Bay is another organization, focusing on protecting California 's Santa Monica Bay , by sponsoring beach cleanup programs along with other activities. Marina DeBris is an artist focusing most of her recent work on educating people about beach trash. Interactive sites like Adrift demonstrate where marine plastic

2754-536: Is carried, over time, on the worlds ocean currents. On 11 April 2013 in order to create awareness, artist Maria Cristina Finucci founded the Garbage Patch State at UNESCO –Paris in front of Director General Irina Bokova . First of a series of events under the patronage of UNESCO and of Italian Ministry of the Environment. Forty-eight plastics manufacturers from 25 countries, are members of

2856-546: Is determined by GPS or Argos system positions at the surface. The data is transmitted to shore via satellite, and is freely available to everyone, without restrictions. The Argo program is named after the Greek mythical ship Argo to emphasize the complementary relationship of Argo with the Jason satellite altimeters. Both the standard Argo floats and the 4 satellites launched so far to monitor changing sea-level all operate on

2958-436: Is forced out of the float's pressure case and expands a rubber bladder at the bottom end of the float. As the bladder expands, the float becomes less dense than seawater and rises to the surface. Upon finishing its tasks at the surface, the float withdraws the oil and descends again. A handful of companies and organizations manufacture profiling floats used in the Argo program. APEX floats, made by Teledyne Webb Research , are

3060-730: Is found on the floor of the Arctic ocean. Although an increasing number of studies have been focused on plastic debris accumulation on the coasts, in off-shore surface waters, and that ingested by marine organisms that live in the upper levels of the water column, there is limited information on debris in the mesopelagic and deeper layers. Studies that have been done have conducted research through bottom sampling, video observation via remotely operated vehicles (ROVs), and submersibles. They are also mostly limited to one-off projects that do not extend long enough to show significant effects of deep-sea debris over time. Research thus far has shown that debris in

3162-461: Is known as beach litter or tidewrack. Deliberate disposal of wastes at sea is called ocean dumping . Naturally occurring debris, such as driftwood and drift seeds , are also present. With the increasing use of plastic , human influence has become an issue as many types of (petrochemical) plastics do not biodegrade quickly, as would natural or organic materials. The largest single type of plastic pollution (~10%) and majority of large plastic in

RAFOS float - Misplaced Pages Continue

3264-728: Is managed by the Argo Data Management Team. Argo is also supported by the Group on Earth Observations, and has been endorsed since its beginnings by the World Climate Research Programme's CLIVAR Project (Variability and predictability of the ocean-atmosphere system), and by the Global Ocean Data Assimilation Experiment (GODAE OceanView). A program called Argo was first proposed at OceanObs 1999 which

3366-449: Is ocean-based. A wide variety of man-made objects can become marine debris; plastic bags , balloons , buoys , rope , medical waste , glass and plastic bottles , cigarette stubs , cigarette lighters , beverage cans , polystyrene , lost fishing line and nets , and various wastes from cruise ships and oil rigs are among the items commonly found to have washed ashore. Six-pack rings , in particular, are considered emblematic of

3468-421: Is plastic. Plastics accumulate because they typically do not biodegrade as many other substances do. They photodegrade on exposure to sunlight, although they do so only under dry conditions, as water inhibits photolysis . In a 2014 study using computer models, scientists from the group 5 Gyres, estimated 5.25 trillion pieces of plastic weighing 269,000 tons were dispersed in oceans in similar amount in

3570-549: Is still in its infancy. However, some projects have been started which used ships with nets (Ocean Voyages Institute/Kaisei 2009 & 2010 and New Horizon 2009) to catch some plastics, primarily for research purposes. There is also Bluebird Marine System's SeaVax which was solar- and wind-powered and had an onboard shredder and cargo hold. The Sea Cleaners' Manta ship is similar in concept. Another method to gather artificial litter has been proposed by The Ocean Cleanup 's Boyan Slat . He suggested using platforms with arms to gather

3672-737: Is that Argo floats now transmit much more data than was previously possible and they spend only about 20 minutes on the sea surface rather than 8–12 hours, greatly reducing problems such as grounding and bio-fouling. The average life span of Argo floats has increased greatly since the program began, first exceeding 4-year mean lifetime for floats deployed in 2005. Ongoing improvements should result in further extensions to 6 years and longer. As of June 2014, new types of floats were being tested to collect measurements much deeper than can be reached by standard Argo floats. These "Deep Argo" floats are designed to reach depths of 4000 or 6000 metres, versus 2000 metres for standard floats. This will allow

3774-424: Is to quantify the ocean heat content (OHC). The Argo fleet consists of almost 4000 drifting "Argo floats" (as profiling floats used by the Argo program are often called) deployed worldwide. Each float weighs 20–30 kg. In most cases probes drift at a depth of 1000 metres. Experts call this the parking depth. Every 10 days, by changing their buoyancy , they dive to a depth of 2000 metres and then move to

3876-466: The Gulf Stream and Kuroshio ), extension of observations into deep water and the addition of sensors for monitoring biological and chemical changes in the oceans. In November 2012 an Indian float in the Argo array gathered the one-millionth profile (twice the number collected by research vessels during all of the 20th century) an event that was reported in several press releases. As can be seen in

3978-705: The United States Congress passed the Ocean Dumping Act , giving the Environmental Protection Agency power to monitor and regulate the dumping of sewage sludge, industrial waste, radioactive waste and biohazardous materials into the nation's territorial waters. The Act was amended sixteen years later to include medical wastes . It is illegal to dispose of any plastic in US waters. Property law , admiralty law and

4080-635: The food chain . In efforts to prevent and mediate marine debris and pollutants, laws and policies have been adopted internationally, with the UN including reduced marine pollution in Sustainable Development Goal 14 "Life Below Water". Depending on relevance to the issues and various levels of contribution, some countries have introduced more specified protection policies. Moreover, some non-profits, NGOs, and government organizations are developing programs to collect and remove plastics from

4182-661: The law of the sea may be of relevance when lost, mislaid, and abandoned property is found at sea. Salvage law rewards salvors for risking life and property to rescue the property of another from peril. On land the distinction between deliberate and accidental loss led to the concept of a " treasure trove ". In the United Kingdom , shipwrecked goods should be reported to a Receiver of Wreck , and if identifiable, they should be returned to their rightful owner. A large number of groups and individuals are active in preventing or educating about marine debris. For example, 5 Gyres

RAFOS float - Misplaced Pages Continue

4284-407: The sea-surface . As they move they measure conductivity and temperature profiles as well as pressure . Scientists calculate salinity and density from these measurements. Seawater density is important in determining large-scale motions in the ocean. Average current velocities at 1000 metres are directly measured by the distance and direction a float drifts while parked at that depth, which

4386-602: The COVID-19 pandemic have been seen in Hong Kong, where disposable masks have ended up along the beaches of Soko’s islands. This may be attributed to the increased production of medical products (masks and gloves) during the pandemic, leading to a rise in unconventional disposal of these products. Techniques for collecting and removing marine (or riverine) debris include the use of debris skimmer boats (pictured) . Devices such as these can be used where floating debris presents

4488-563: The EU parliament voted for an EU-wide ban on single-use plastic products such as plastic straws, cutlery, plates, and drink containers, polystyrene food and drink containers, plastic drink stirrers and plastic carrier bags and cotton buds. The law will take effect in 2021. In the waters of the United States, there have been many observed consequences of pollution including: hypoxic zones , harmful agal blooms, and threatened species. In 1972,

4590-400: The Earth's climate since they are the main heat transfer mechanism. They are the reason for heat flux between hot and cold regions, and in a larger sense drive almost every understood circulation. These currents also affect marine debris , and vice versa. In an economical aspect, a better understanding can help reducing costs of shipping, since the currents would help boats reduce fuel costs. In

4692-589: The Global Plastic Associations for solutions on Marine Litter, have made the pledge to help prevent marine debris and to encourage recycling. Marine debris is a widespread problem, not only the result of activities in coastal regions. Plastic debris from inland states come from two main sources: ordinary litter and materials from open dumps and landfills that blow or wash away to inland waterways and wastewater outflows. The refuse finds its way from inland waterways, rivers, streams and lakes to

4794-479: The Northern and Southern Hemispheres. Some materials and activities used in industrial activities that do not readily degrade, that persist in the environment, and tend to accumulate over time. The activities can include fishing, boating, and aquaculture industries that harvest or use resources in the marine environment and may lose or discard gear, materials, machinery or solid wastes from industrial processes into

4896-623: The US. About 90% of all profiles acquired are made available to global access within 24 hours, with the remaining profiles becoming available soon thereafter. For a researcher to use data acquired via the GTS or from the Argo Global Data Centres (GDACs) does require programming skills. The GDACs supply multi-profile files that are a native file format for Ocean DataView. For any day there are files with names like 20121106_prof.nc that are called multi-profile files. This example

4998-410: The amount of marine debris found on beaches with around 55% being a pandemic-related trash items. Although the pandemic-related trash has shown up along the beaches of Kenya, it has not made its way into the water. The reduction of litter in the ocean could be a result of the closing of beaches and lack of movement during the pandemic, so less trash was likely to end up in the ocean. Additional impacts of

5100-489: The beaches for Lego dragons. It also provided valuable insight in studying marine plastic degradation. In Halifax Harbour, Nova Scotia, 52% of items were generated by recreational use of an urban park, 14% from sewage disposal and only 7% from shipping and fishing activities. Around four-fifths of oceanic debris is from rubbish blown onto the water from landfills , and urban runoff . Some studies show that marine debris may be dominant in particular locations. For example,

5202-406: The data collected by the satellites, one major step is to compute the float's route over time. This is done by looking at the travel time of the signals from the moored speakers to the float, computed from the emission time (known accurately), the reception time (known from the float's clock and corrected if the clock had moved). Then, because the speed of sound is known to 0.3% in sea, the position of

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5304-528: The debris found – 89% of which was single-use – and metal, making up 26%. Plastic debris was found at the bottom of the Mariana Trench, at a depth of 10,898m, and plastic bags were found entangled in hydrothermal vent and cold seep communities. The 10 largest emitters of oceanic plastic pollution worldwide are, from the most to the least, China, Indonesia, Philippines, Vietnam, Sri Lanka, Thailand, Egypt, Malaysia, Nigeria, and Bangladesh, largely through

5406-619: The debris, situated inside the current of gyres. The SAS Ocean Phoenix ship is somewhat similar in design. In June 2019, Ocean Voyages Institute , conducted a cleanup utilizing GPS trackers and existing maritime equipment in the North Pacific Subtropical Convergence Zone setting the record for the largest mid-ocean cleanup accomplished in the North Pacific Gyre and removed over 84,000 pounds of polymer nets and consumer plastic trash from

5508-485: The debris. There are also projects that stimulate fishing boats to remove any litter they accidentally fish up while fishing for fish. Elsewhere, "trash traps" are installed on small rivers to capture waterborne debris before it reaches the sea. For example, South Australia 's Adelaide operates a number of such traps, known as "trash racks" or "gross pollutant traps" on the Torrens River , which flows (during

5610-639: The deep-ocean is in fact impacted by anthropogenic activities, and plastic has been frequently observed in the deep-sea, especially in areas off-shore of heavily populated regions, such as the Mediterranean. Litter, made from diverse materials that are lighter than surface water (such as glasses , metals and some plastics), have been found to spread over the floor of seas and open oceans, where it can become entangled in corals and interfere with other sea-floor life , or even become buried under sediment, making clean-up extremely difficult, especially due to

5712-539: The discharge of "garbage, rubbish, ashes or organic refuse" from "any vessel in Australian waters" without prior written permission from the federal government. It also required permission for scuttling . The act was passed in response to large amounts of garbage washing up on the beaches of Sydney and Newcastle from vessels outside the reach of local governments and the New South Wales government. It

5814-654: The drafting of Chapter 3 (Working Group 1) of the IPCC Fifth Assessment Report (released September 2013) and an appendix was added to that chapter to emphasize the profound change that had taken place in the quality and volume of ocean data since the IPCC Fourth Assessment Report and the resulting improvement in confidence in the description of surface salinity changes and upper-ocean heat content. Argo data were used along with sea level change data from satellite altimetry in

5916-478: The entanglement of large numbers of Antarctic fur seals . Thirteen companies have an individual contribution of 1% or more of the total branded plastic observed in the audit events: The Coca-Cola Company, PepsiCo, Nestlé, Danone, Altria, Bakhresa Group, Wings, Unilever, Mayora Indah, Mondelez International, Mars, Incorporated, Salim Group, and British American Tobacco. All 13 companies produce food, beverage, or tobacco products. The top company, The Coca-Cola Company,

6018-607: The first time in 1999 in Maryland (USA) and outlined the principles of global data sharing. The Argo Steering Team made a 10-year report to OceanObs-2009 and received suggestions on how the array might be improved. These suggestions included enhancing the array at high latitudes, in marginal seas (such as the Gulf of Mexico and the Mediterranean) and along the equator, improved observation of strong boundary currents (such as

6120-470: The float can be determined to about 1 km by an iterative circular tracking procedure. The doppler effect can also be taken into account. Since the float's speed is not known, a first closing speed is determined by measuring the shift in time arrival between two transmissions, where the float is considered not to have moved. The Argo project is an international collaboration between 50 research and operational agencies from 26 countries that aims to measure

6222-428: The float itself to do the listening and computing, and a moored sound source. From the arrival time of the signals from two or more sound sources, and the previous location of the float, its current location can easily be determined to considerable (<1 km) accuracy. For instance, the float will listen for three sources and store the time of arrival for the two largest signals heard from each source. The location of

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6324-403: The float will be computed onshore. The floats consist of 8 cm by 1.5 to 2.2 m long glass pipe that contain a hydrophone, signal processing circuits, a microprocessor, a clock and a battery. A float weighs about 10 kg. The lower end is sealed with a flat aluminium endplate where all electrical and mechanical penetrators are located. The glass thickness is about 5 mm, giving the float

6426-432: The floats have been able to measure different amounts of dissolved gases, and even to carry small experiments in situ. Marine debris Marine debris , also known as marine litter , is human-created solid material that has deliberately or accidentally been released in seas or the ocean . Floating oceanic debris tends to accumulate at the center of gyres and on coastlines , frequently washing aground, when it

6528-414: The global ocean heat content . They determine that areas of the world with high surface salinity are getting saltier and areas of the world with relatively low surface salinity are getting fresher. This has been described as 'the rich get richer and the poor get poorer'. Scientifically speaking, the distributions of salt are governed by the difference between precipitation and evaporation. Areas, such as

6630-409: The global mapping of the ocean characteristics, or for example how floats systematically shoal (upwell) as they approach anticyclonic meanders and deepen (downwell) as they approach cyclonic meanders. On the left is a typical set of data from a RAFOS float. Today, such floats remain the best way to systematically probe the ocean's interior, since it is automatic and self-sufficient. In recent developments

6732-487: The history section, enhancements are now planned in the equatorial regions of the oceans, in boundary currents and in marginal seas. This requires that the total number of floats be increased from the original plan of 3000 floats to a 4000-float array. One consequence of the use of profiling floats to sample the ocean is that seasonal bias can be removed. The diagram opposite shows the count of all float profiles acquired each month by Argo south of 30°S (upper curve) from

6834-422: The incoming data with a reference 80-second signal. This permits to get rid of any noise appearing during the travel of the wave by floating particles or fish. The detection scheme can be simplified by keeping only the information of positive or negative signal, allowing to work with a single bit of new information at each time step. This method works very well, and allows the use of small micro-processors, enabling

6936-405: The main lower level food group for the marine food chain and over half of the photosynthesis on earth. One of the most efficient and cost effective ways to help reduce the amount of plastic entering our oceans is to not participate in using single-use plastics, avoid plastic bottled drinks such as water bottles, use reusable shopping bags, and to buy products with reusable packaging . The ocean

7038-726: The most common element of the current array. SOLO and SOLO-II floats (the latter use a reciprocating pump for buoyancy changes, unlike screw-driven pistons in other floats) were developed at Scripps Institution of Oceanography . Other types include the NINJA float, made by the Tsurumi Seiki Co. of Japan, and the ARVOR, DEEP-ARVOR & PROVOR floats developed by IFREMER in France, in industrial partnership with French Company nke instrumentation. Most floats use sensors made by Sea-Bird Scientific ( https://www.seabird.com/ ) , which also makes

7140-418: The northern North Pacific Ocean , where precipitation dominates evaporation are fresher than average. The implication of their result is that the Earth is seeing an intensification of the global hydrological cycle . Argo data are also being used to drive computer models of the climate system leading to improvements in the ability of nations to forecast seasonal climate variations. Argo data were critical in

7242-403: The ocean as they vary with depth, but an increasing number of floats also carry other sensors, such as for measuring dissolved oxygen and ultimately other variables of biological and chemical interest such as chlorophyll, nutrients and pH. An extension to the Argo project called BioArgo is being developed and, when implemented, will add a biological and chemical component to this method of sampling

7344-418: The ocean at which depth the speed of sound is minimal, in average around 1200 m deep. It acts as a wave-guide for sound, and low frequency sound waves within the channel may travel thousands of miles before dissipating. The SOFAR channel is centred on the depth where the cumulative effect of temperature and water pressure (and, to a smaller extent, salinity) combine to create the region of minimum sound speed in

7446-462: The ocean, lakes, and rivers. These nets, often nearly invisible in the dim light, can be left tangled on a rocky reef or drifting in the open sea. They can entangle fish , dolphins , sea turtles , sharks , dugongs , crocodiles , seabirds , crabs , and other creatures, including the occasional human diver. Acting as designed, the nets restrict movement, causing starvation, laceration and infection, and suffocation in those that need to return to

7548-463: The ocean. In May/June 2020, Ocean Voyages Institute conducted a cleanup expedition in the Gyre and set a new record for the largest mid-ocean cleanup accomplished in the North Pacific Gyre which removed over 170 tons (340,000 pounds) of consumer plastics and ghostnets from the ocean. Utilizing custom designed GPS satellite trackers which are deployed by vessels of opportunity , Ocean Voyages Institute

7650-690: The ocean. However, in 2017 the UN estimated that by 2050 there will be more plastic than fish in the oceans if substantial measures are not taken. Researchers classify debris as either land- or ocean-based; in 1991, the United Nations Joint Group of Experts on the Scientific Aspects of Marine Pollution estimated that up to 80% of the pollution was land-based, with the remaining 20% originating from catastrophic events or maritime sources. More recent studies have found that more than half of plastic debris found on Korean shores

7752-410: The ocean. Though ocean and coastal area cleanups are important, it is crucial to address plastic waste that originates from inland and landlocked states. At the systems level, there are various ways to reduce the amount of debris entering our waterways: Consumers can help to reduce the amount of plastic entering waterways by reducing usage of single-use plastics, avoiding microbeads, participate in

7854-589: The oceans is discarded and lost nets from the fishing industry. Waterborne plastic poses a serious threat to fish , seabirds , marine reptiles , and marine mammals , as well as to boats and coasts. Dumping, container spillages, litter washed into storm drains and waterways and wind-blown landfill waste all contribute to this problem. This increased water pollution has caused serious negative effects such as discarded fishing nets capturing animals, concentration of plastic debris in massive marine garbage patches , and increasing concentrations of contaminants in

7956-502: The oceans. The antenna for satellite data collection is mounted at the top of the float which extends clear of the sea surface after it completes its ascent. The ocean is saline, hence an electrical conductor, so that radio communications from under the sea surface are not possible. Early in the program Argo floats exclusively used slow mono-directional satellite communications but the majority of floats being deployed in mid-2013 use rapid bi-directional communications. The result of this

8058-451: The part of the wave furthest from the channel axis travels faster, so the wave turns back toward the channel axis. As a result, the sound waves trace a path that oscillates across the SOFAR channel axis. This principle is similar to long distance transmission of light in an optical fiber. In this channel, a sound has a range of over 2000 km. To use a RAFOS float, one has to submerge it in

8160-427: The passage of food and causing death through starvation or infection. Tiny floating plastic particles also resemble zooplankton , which can lead filter feeders to consume them and cause them to enter the ocean food chain . In addition, plastic in the marine environment that contaminates the food chain can have repercussions on the viability of fish and shellfish species. In Kenya, the COVID-19 pandemic has impacted

8262-491: The plot opposite, by early 2018 the Bio-Argo program is expanding rapidly. The critical capability of an Argo float is its ability to rise and descend in the ocean on a programmed schedule. The floats do this by changing their effective density. The density of any object is given by its mass divided by its volume. The Argo float keeps its mass constant, but by altering its volume, it changes its density. To do this, mineral oil

8364-432: The preliminary treatment screens on wastewater plants. These beads are harmful to the organisms in the ocean, especially filter feeders, because they can easily ingest the plastic and become sick. The microplastics are such a concern because it is difficult to clean them up due to their size, so humans can try to avoid using these harmful plastics by purchasing products that use environmentally safe exfoliates. Marine debris

8466-463: The problem. The US military used ocean dumping for unused weapons and bombs, including ordinary bombs, UXO , landmines and chemical weapons from at least 1919 until 1970. Millions of pounds of ordnance were disposed of in the Gulf of Mexico and off the coasts of at least 16 states, from New Jersey to Hawaii (although these, of course, do not wash up onshore, and the US is not the only country who has practiced this). Eighty percent of marine debris

8568-643: The retention of microplastics at certain locations. A Deep-sea Debris database by the Global Oceanographic Data Center of the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), showing thirty years of photos and samples of marine debris since 1983, was made public in 2017. From the 5,010 dives in the database, using both ROVs and deep-sea submersibles, 3,425 man-made debris items were counted. The two most significant types of debris were macro-plastic, making up 33% of

8670-560: The rivers Yangtze, Indus, Yellow, Hai, Nile, Ganges, Pearl, Amur, Niger, and the Mekong, and accounting for "90 percent of all the plastic that reaches the world's oceans." An estimated 10,000 containers at sea each year are lost by container ships , usually during storms. One spillage occurred in the Pacific Ocean in 1992, when thousands of rubber ducks and other toys (now known as the "Friendly Floatees") went overboard during

8772-462: The sail-ship era knowledge was even more essential. Even today, the round-the-world sailing competitors employ surface currents to their benefit. Ocean currents are also very important in the dispersal of many life forms. An example is the life-cycle of the European Eel. The SOFAR channel (short for Sound Fixing and Ranging channel), or deep sound channel (DSC), is a horizontal layer of water in

8874-451: The same compressibility as the surrounding seawater. This is often achieved by a compressible element, as a piston in a cylinder, so that the CPU can change the volume according to changes in pressure. An error of about 10% in the setting can lead to a 50 m depth difference once in water. This is why floats are ballasted in tanks working at high pressure. Once the float's mission is over and

8976-504: The specified location, so that it will get carried by the current. Then, every so often (usually every 6 or 8 hours) an 80-second sound signal is sent from moored emitters. Using the fact that a signal transmitted in the ocean preserves its phase structure (or pattern) for several minutes, it has been thought to use signals in which the frequency increases linearly of 1.523 Hz from start to end centered around 250 Hz. Then receivers would listen for specific phase structures, by comparing

9078-416: The start of the program to November 2012 compared with the same diagram for all other data available. The lower curve shows a strong annual bias with four times as many profiles being collected in austral summer than in austral winter. For the upper (Argo) plot, there is no bias apparent. One of the critical features of the Argo model is that of global and unrestricted access to data in near real-time. When

9180-449: The surface to breathe. A growing concern regarding plastic pollution in the marine ecosystem is the use of microplastics. Microplastics are beads of plastic less than 5 millimeters wide, and they are commonly found in hand soaps, face cleansers, and other exfoliators. When these products are used, the microplastics go through the water filtration system and into the ocean, but because of their small size they are likely to escape capture by

9282-420: The surface. Since the density of the float is its mass divided by volume, it needs to change its volume by 0.0109 × 16,600 = 181 cm to drive that excursion; a small amount of that volume change is provided by the compressibility of the float itself, and excess buoyancy is required at the surface in order to keep the antenna above water. All Argo floats carry sensors to measure the temperature and salinity of

9384-448: The surfacing. It usually takes three days for the satellite to collect all the dataset. An isobaric float aims to follow a constant pressure plane, by adjusting the ballast's weight to attain buoyancy to a certain depth. It is the most easily achieved model. To achieve an isobaric float, its compressibility must be much lower than that of seawater. In that case, if the float were to be moved upwards from equilibrium, it will expand less than

9486-414: The surrounding seawater, leading to a restoring force pushing it downwards, back to its equilibrium position. Once correctly balanced, the float will remain in a constant pressure field. The aim of an isopycnal float is to follow the density planes, that is to attain neutral buoyancy for constant density. To achieve this, it is necessary to remove pressure induced restoring forces, thus the float has to have

9588-498: The types and numbers of industrial operations nearby. Materials like plastic or foam can break down into smaller particles and may look like small sea creatures to wildlife such as birds, cetaceans, and fish, and they may eat these particles. Indigestible material may accumulate in the gut creating blockages or a false sense of fullness and eventually death from lack of appropriate nutrient intake. Ghost nets are fishing nets that have been abandoned, lost, or otherwise discarded in

9690-457: The water column. Near the surface, the rapidly falling temperature causes a decrease in sound speed, or a negative sound speed gradient. With increasing depth, the increasing pressure causes an increase in sound speed, or a positive sound speed gradient. The depth where the sound speed is at a minimum is the sound channel axis. This is a characteristic that can be found in optical guides. If a sound wave propagates away from this horizontal channel,

9792-442: The water or onto shorelines. This can include anything as large as a fishing boat or as small as particle from a Styrofoam lobster float. In 2003, a study was conducted to identify types, amounts, sources, and effects of persistent industrial marine debris in the coastal waters and along the shores of Charlotte County, New Brunswick , and examine any relationship between the amount and types of persistent industrial marine debris, and

9894-618: The wet season) into Gulf St Vincent . In lakes or near the coast, manual removal can also be used. Project AWARE for example promotes the idea of letting dive clubs clean up litter, for example as a diving exercise. Once a year there is a diving marine debris removal operation in Scapa Flow in Orkney , run by Ghost Fishing UK, funded by World Animal Protection and Fat Face Foundation. Cleanup of marine debris can be stymied by inadequate collaboration across levels of government, and

9996-440: The wide area of its dispersal compared to shipwrecks . Plastics that are usually negatively buoyant can sink with the adherence of phytoplankton and the aggregation of other organic particles. Other oceanic processes that affect circulation, such as coastal storms and offshore convection, play a part in transferring large volumes of particles and debris. Submarine topographic features can also augment downwelling currents, leading to

10098-492: Was a conference organised by international agencies with the aim of creating a coordinated approach to ocean observations. The original Argo prospectus was created by a small group of scientists, chaired by Dean Roemmich , who described a program that would have a global array of about 3000 floats in place by sometime in 2007. The 3000-float array was achieved in November 2007 and was global. The Argo Steering Team met for

10200-543: Was considered necessary because of the decrease in the Rossby radius of deformation which governs the scale of oceanographic features, such as eddies. By 2007 this was largely achieved, but the target resolution has never yet been completely achieved in the deep southern ocean. Efforts are being made to complete the original plan in all parts of the world oceans but this is difficult in the deep Southern Ocean as deployment opportunities occur only very rarely. As mentioned in

10302-775: Was repealed and replaced by the Environment Protection (Sea Dumping) Act 1981 , which gave effect to the London Convention. In 1972 and 1974, conventions were held in Oslo and Paris respectively, and resulted in the passing of the OSPAR Convention , an international treaty controlling marine pollution in the north-east Atlantic Ocean . The Barcelona Convention protects the Mediterranean Sea . The Water Framework Directive of 2000

10404-423: Was responsible for 11% (CI95% = 10 to 12%), significantly greater than any other company. The top 5 companies were responsible for 24% of the branded plastic; 56 companies were responsible for greater than 50% of the branded plastic; and 19,586 companies were responsible for all of the branded plastic. The contributions of the top companies may be an underestimation because there were brands that were not attributed to

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