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The Oceans Portal
A portal dedicated to oceans, seas, oceanography and related topics

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Surface view of the Atlantic Ocean

The ocean (also the sea or the world ocean) is the body of salt water that covers approximately 70.8% of the surface of Earth and contains 97% of Earth's water. An ocean can also refer to any of the large bodies of water into which the world ocean is conventionally divided. Separate names are used to identify five different areas of the ocean: Pacific (the largest), Atlantic, Indian, Antarctic/Southern, and Arctic (the smallest). Seawater covers approximately 361,000,000 km2 (139,000,000 sq mi) of the planet. The ocean is the principal component of Earth's hydrosphere, and therefore integral to life on Earth. Acting as a huge heat reservoir, the ocean influences climate and weather patterns, the carbon cycle, and the water cycle. (Full article...)

Waves in Pacifica, California

The sea in a general sense refers to the ocean or world ocean, the body of salty water that covers approximately 71% of the Earth's surface. Used in a particular sense the word sea refers to particular seas either as second-order sections of the ocean, such as the Mediterranean Sea, or as certain large, entirely landlocked, saltwater lakes, such as the Caspian Sea. The sea moderates Earth's climate and has important roles in the water, carbon, and nitrogen cycles. Humans harnessing and studying the sea have been recorded since ancient times, and evidenced well into prehistory, while its modern scientific study is called oceanography. The most abundant solid dissolved in seawater is sodium chloride. The water also contains salts of magnesium, calcium, potassium, and mercury, amongst many other elements, some in minute concentrations. Salinity varies widely, being lower near the surface and the mouths of large rivers and higher in the depths of the ocean; however, the relative proportions of dissolved salts vary little across the oceans. (Full article...)

Oceanography (from Ancient Greek ὠκεανός (ōkeanós) 'ocean', and γραφή (graphḗ) 'writing'), also known as oceanology and ocean science, is the scientific study of the oceans. It is an Earth science, which covers a wide range of topics, including ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamics; plate tectonics and the geology of the sea floor; and fluxes of various chemical substances and physical properties within the ocean and across its boundaries. These diverse topics reflect multiple disciplines that oceanographers utilize to glean further knowledge of the world ocean, including astronomy, biology, chemistry, climatology, geography, geology, hydrology, meteorology and physics. Paleoceanography studies the history of the oceans in the geologic past. An oceanographer is a person who studies many matters concerned with oceans, including marine geology, physics, chemistry and biology. (Full article...)

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Argo is an international program that uses profiling floats to observe temperature, salinity, currents, and, recently, bio-optical properties in the Earth's oceans; it has been operational since the early 2000s. The real-time data it provides is used in climate and oceanographic research. A special research interest 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 (the so-called parking depth) and, every 10 days, by changing their buoyancy, dive to a depth of 2000 metres and then move to the sea-surface, measuring conductivity and temperature profiles as well as pressure. From these, salinity and density can be calculated. 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 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. (Full article...)
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Landing on Stac Lee (from St Kilda)

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In the news

29 January 2023 – 2022–23 South-West Indian Ocean cyclone season
The death toll from Cyclone Cheneso's landfall in Madagascar has increased to 25, with 21 others still missing. (AFP via ABS-CBN News)
20 January 2023 –
A Dominican man who was lost in the Caribbean Sea for 24 days is rescued by the Colombian Navy. (AP)
10 January 2023 – Territorial disputes in the South China Sea
The Supreme Court of the Philippines nullifies the country's Joint Marine Seismic Undertaking agreement with the China National Offshore Oil Corporation and Petrovietnam to conduct joint oil and gas exploration activities within the Philippine exclusive economic zone in the South China Sea since 2005, citing the unconstitutionality of permitting foreign corporations and governments to exploit the country's natural resources. (Reuters via CNN)
7 January 2023 –
Five people are killed and ten others are missing after a boat carrying migrants sinks off the coast of Tunisia. (Al Jazeera)
2 January 2023 – 2023 Gold Coast mid-air collision
Four people are killed and eight others are injured when two helicopters collide near the Sea World theme park in Gold Coast, Queensland, Australia. (ABC News Australia)



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