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<span>Applications</span> </div> </a> <button aria-controls="toc-Applications-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Applications subsection</span> </button> <ul id="toc-Applications-sublist" class="vector-toc-list"> <li id="toc-Other_applications" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Other_applications"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Other applications</span> </div> </a> <ul id="toc-Other_applications-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-In_nature" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#In_nature"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>In nature</span> </div> </a> <ul id="toc-In_nature-sublist" class="vector-toc-list"> </ul> 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Available in 12 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-12" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">12 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Kan%C3%A1l_SOFAR" title="Kanál SOFAR – Czech" lang="cs" hreflang="cs" data-title="Kanál SOFAR" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/SOFAR-Kanal" title="SOFAR-Kanal – German" lang="de" hreflang="de" data-title="SOFAR-Kanal" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Canal_SOFAR" title="Canal SOFAR – Spanish" lang="es" hreflang="es" data-title="Canal SOFAR" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%DA%A9%D8%A7%D9%86%D8%A7%D9%84_%D8%A7%D8%B3%E2%80%8C%D8%A7%D9%88%D8%A7%D9%81%E2%80%8C%D8%A7%DB%8C%E2%80%8C%D8%A2%D8%B1" title="کانال اس‌اواف‌ای‌آر – Persian" lang="fa" hreflang="fa" data-title="کانال اس‌اواف‌ای‌آر" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Canal_SOFAR" title="Canal SOFAR – French" lang="fr" hreflang="fr" data-title="Canal SOFAR" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%86%8C%ED%8C%8C_%EC%B1%84%EB%84%90" title="소파 채널 – Korean" lang="ko" hreflang="ko" data-title="소파 채널" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Canale_SOFAR" title="Canale SOFAR – Italian" lang="it" hreflang="it" data-title="Canale SOFAR" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E6%B7%B1%E6%B5%B7%E3%82%B5%E3%82%A6%E3%83%B3%E3%83%89%E3%83%81%E3%83%A3%E3%83%8D%E3%83%AB" title="深海サウンドチャネル – Japanese" lang="ja" hreflang="ja" data-title="深海サウンドチャネル" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/SOFAR-kanal" title="SOFAR-kanal – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="SOFAR-kanal" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Canal_SOFAR" title="Canal SOFAR – Portuguese" lang="pt" hreflang="pt" data-title="Canal SOFAR" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9F%D0%BE%D0%B4%D0%B2%D0%BE%D0%B4%D0%BD%D1%8B%D0%B9_%D0%B7%D0%B2%D1%83%D0%BA%D0%BE%D0%B2%D0%BE%D0%B9_%D0%BA%D0%B0%D0%BD%D0%B0%D0%BB" title="Подводный звуковой канал – Russian" lang="ru" hreflang="ru" data-title="Подводный звуковой канал" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/SOFAR%E9%80%9A%E9%81%93" title="SOFAR通道 – Chinese" lang="zh" hreflang="zh" data-title="SOFAR通道" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a 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class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Underwater_speed_of_sound.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Underwater_speed_of_sound.svg/220px-Underwater_speed_of_sound.svg.png" decoding="async" width="220" height="354" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Underwater_speed_of_sound.svg/330px-Underwater_speed_of_sound.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Underwater_speed_of_sound.svg/440px-Underwater_speed_of_sound.svg.png 2x" data-file-width="377" data-file-height="606" /></a><figcaption><span style="font-size:95%;">Underwater sound speed as a function of depth. Data derived from readings taken north of <a href="/wiki/Hawaii" title="Hawaii">Hawaii</a> in the <a href="/wiki/Pacific_Ocean" title="Pacific Ocean">Pacific Ocean</a> and sourced from the <a href="/wiki/World_Ocean_Atlas" title="World Ocean Atlas">World Ocean Atlas</a>, 2005 edition. Note the SOFAR channel axis at <span class="nowrap"><i>ca.</i> 750<span style="white-space: nowrap;"> </span>m</span> depth, where sound speed is shown at its lowest.</span></figcaption></figure> <p>The <b>SOFAR channel</b> (short for <b>sound fixing and ranging channel</b>), or <b>deep sound channel</b> (<b>DSC</b>),<sup id="cite_ref-NTRP_1-02_1-0" class="reference"><a href="#cite_note-NTRP_1-02-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> is a horizontal layer of water in the ocean at which depth the <a href="/wiki/Speed_of_sound" title="Speed of sound">speed of sound</a> is at its minimum. The SOFAR channel acts as a <a href="/wiki/Waveguide" title="Waveguide">waveguide</a> for sound, and low frequency <a href="/wiki/Underwater_acoustics" title="Underwater acoustics">sound waves</a> within the channel may travel thousands of miles before dissipating. An example was reception of coded signals generated by the US Navy-chartered ocean surveillance vessel <a href="/wiki/MV_Cory_Chouest" title="MV Cory Chouest"><i>Cory Chouest</i></a> off <a href="/wiki/Heard_Island" class="mw-redirect" title="Heard Island">Heard Island</a>, located in the southern Indian Ocean (between Africa, Australia and Antarctica), by hydrophones in portions of all five major ocean basins and as distant as the <a href="/wiki/North_Atlantic" class="mw-redirect" title="North Atlantic">North Atlantic</a> and <a href="/wiki/North_Pacific" class="mw-redirect" title="North Pacific">North Pacific</a>.<sup id="cite_ref-Munk_2-0" class="reference"><a href="#cite_note-Munk-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-AOML_3-0" class="reference"><a href="#cite_note-AOML-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>note 1<span class="cite-bracket">]</span></a></sup> </p><p>This phenomenon is an important factor in ocean surveillance.<sup id="cite_ref-Cone_6-0" class="reference"><a href="#cite_note-Cone-6"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-ICAA_8-0" class="reference"><a href="#cite_note-ICAA-8"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> The deep sound channel was discovered and described independently by <a href="/wiki/Maurice_Ewing" title="Maurice Ewing">Maurice Ewing</a> and <a href="/wiki/J._Lamar_Worzel" title="J. Lamar Worzel">J. Lamar Worzel</a> at <a href="/wiki/Columbia_University" title="Columbia University">Columbia University</a> and <a href="/wiki/Leonid_Brekhovskikh" title="Leonid Brekhovskikh">Leonid Brekhovskikh</a> at the <a href="/wiki/Lebedev_Physics_Institute" class="mw-redirect" title="Lebedev Physics Institute">Lebedev Physics Institute</a> in the 1940s.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Kaharl_10-0" class="reference"><a href="#cite_note-Kaharl-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> In testing the concept in 1944 Ewing and Worzel hung a hydrophone from <a href="/wiki/USS_Saluda_(IX-87)" class="mw-redirect" title="USS Saluda (IX-87)"><i>Saluda</i></a>, a sailing vessel assigned to the <a href="/wiki/Underwater_Sound_Laboratory" class="mw-redirect" title="Underwater Sound Laboratory">Underwater Sound Laboratory</a>, with a second ship setting off explosive charges up to 900 nmi (1,000 mi; 1,700 km) away.<sup id="cite_ref-HSC-URI_11-0" class="reference"><a href="#cite_note-HSC-URI-11"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Principle">Principle</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=SOFAR_channel&action=edit&section=1" title="Edit section: Principle"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Rays_test.gif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/0/0c/Rays_test.gif" decoding="async" width="436" height="134" class="mw-file-element" data-file-width="436" data-file-height="134" /></a><figcaption>Acoustic pulses travel great distances in the ocean because they are trapped in an acoustic <a href="/wiki/Wave_guide" class="mw-redirect" title="Wave guide">wave guide</a>. This means that as acoustic pulses approach the surface they are turned back towards the bottom, and as they approach the ocean bottom they are turned back towards the surface. The ocean conducts sound very efficiently, particularly sound at low frequencies, i.e., less than a few hundred Hz</figcaption></figure> <p>Temperature is the dominant factor in determining the speed of sound in the ocean. In areas of higher temperatures (e.g. near the ocean surface), there is higher sound speed. Temperature decreases with depth, with sound speed decreasing accordingly until temperature becomes stable and pressure becomes the dominant factor. The axis of the SOFAR channel lies at the point of minimum sound speed at a depth where pressure begins dominating temperature and sound speed increases. This point is at the bottom of the <a href="/wiki/Thermocline" title="Thermocline">thermocline</a> and the top of the deep isothermal layer and thus has some seasonal variance. Other acoustic ducts exist, particularly in the upper <a href="/wiki/Mixed_layer" title="Mixed layer">mixed layer</a>, but the ray paths lose energy with either surface or bottom reflections. In the SOFAR channel, low frequencies, in particular, are refracted back into the duct so that energy loss is small and the sound travels thousands of miles.<sup id="cite_ref-Kaharl_10-1" class="reference"><a href="#cite_note-Kaharl-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> Analysis of Heard Island Feasibility Test data received by the <a href="/wiki/Ascension_Island" title="Ascension Island">Ascension Island</a> <a href="/wiki/Missile_Impact_Locating_System" class="mw-redirect" title="Missile Impact Locating System">Missile Impact Locating System</a> hydrophones at an intermediate range of 9,200 km (5,700 mi; 5,000 nmi) from the source found "surprisingly high" <a href="/wiki/Signal-to-noise_ratio" title="Signal-to-noise ratio">signal-to-noise ratios</a>, ranging from 19 to 30 dB, with unexpected phase stability and amplitude variability after a travel time of about 1 hour, 44 minutes and 17 seconds.<sup id="cite_ref-AOML_3-1" class="reference"><a href="#cite_note-AOML-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:PARKA_I_Track_Acoustic_Enfironment_-_Kaneohe-Alaska_SOFAR_Channel.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/3/35/PARKA_I_Track_Acoustic_Enfironment_-_Kaneohe-Alaska_SOFAR_Channel.png/250px-PARKA_I_Track_Acoustic_Enfironment_-_Kaneohe-Alaska_SOFAR_Channel.png" decoding="async" width="250" height="87" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/3/35/PARKA_I_Track_Acoustic_Enfironment_-_Kaneohe-Alaska_SOFAR_Channel.png/375px-PARKA_I_Track_Acoustic_Enfironment_-_Kaneohe-Alaska_SOFAR_Channel.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/3/35/PARKA_I_Track_Acoustic_Enfironment_-_Kaneohe-Alaska_SOFAR_Channel.png/500px-PARKA_I_Track_Acoustic_Enfironment_-_Kaneohe-Alaska_SOFAR_Channel.png 2x" data-file-width="1731" data-file-height="600" /></a><figcaption>Profile showing sound channel axis and bottom at critical depth. Where bottom profile intrudes into the sound channel propagation is bottom limited.</figcaption></figure> <p>Within the duct sound waves trace a path that oscillates across the SOFAR channel axis so that a single signal will have multiple arrival times with a signature of multiple pulses climaxing in a sharply defined end.<sup id="cite_ref-HSC-URI_11-1" class="reference"><a href="#cite_note-HSC-URI-11"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>note 2<span class="cite-bracket">]</span></a></sup> That sharply defined end representing a near axial arrival path is sometimes termed the SOFAR finale and the earlier ones the SOFAR symphony.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> Those effects are due to the larger sound channel in which ray paths are contained between the surface and critical depth.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>note 3<span class="cite-bracket">]</span></a></sup> Critical depth is the point below the sound speed minimum axis where sound speed increases to equal the maximum speed above the axis. Where the bottom lies above critical depth the sound is attenuated, as is any ray path intersecting the surface or bottom.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>note 4<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Bathymetry-SOFAR_channel_axis%E2%80%94Heard_Island_Feasibility_Test.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/f/f2/Bathymetry-SOFAR_channel_axis%E2%80%94Heard_Island_Feasibility_Test.png/250px-Bathymetry-SOFAR_channel_axis%E2%80%94Heard_Island_Feasibility_Test.png" decoding="async" width="250" height="238" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/f/f2/Bathymetry-SOFAR_channel_axis%E2%80%94Heard_Island_Feasibility_Test.png/375px-Bathymetry-SOFAR_channel_axis%E2%80%94Heard_Island_Feasibility_Test.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/f/f2/Bathymetry-SOFAR_channel_axis%E2%80%94Heard_Island_Feasibility_Test.png/500px-Bathymetry-SOFAR_channel_axis%E2%80%94Heard_Island_Feasibility_Test.png 2x" data-file-width="764" data-file-height="726" /></a><figcaption>Bathymetry profile with SOFAR channel axis depth, Heard Island to Ascension Island.</figcaption></figure> <p>The channel axis varies most with its location reaching the surface and disappearing at high latitudes (above about 60°N or below 60°S) but with sound then traveling in a surface duct. A 1980 report by Naval Ocean Systems Center gives examples in a study of a great circle acoustic path between <a href="/wiki/Perth,_Australia" class="mw-redirect" title="Perth, Australia">Perth, Australia</a> and <a href="/wiki/Bermuda" title="Bermuda">Bermuda</a> with data at eight locations along the path. At both Perth and Bermuda the sound channel axis occurs at a depth of around 1,200 m (3,937 ft). Where the path meets the <a href="/wiki/Antarctic_Convergence" title="Antarctic Convergence">Antarctic Convergence</a> at 52º south there is no deep sound channel but a 30 m (98 ft) in depth surface duct and a shallow sound channel at 200 m (656 ft). As the path turns northward, a station at 43º south, 16º east showed the profile reverting to the SOFAR type at 800 m (2,625 ft).<sup id="cite_ref-Dushaw_23-0" class="reference"><a href="#cite_note-Dushaw-23"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Northrop_24-0" class="reference"><a href="#cite_note-Northrop-24"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Applications">Applications</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=SOFAR_channel&action=edit&section=2" title="Edit section: Applications"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The first practical application began development during <a href="/wiki/World_War_II" title="World War II">World War II</a> when the <a href="/wiki/United_States_Navy" title="United States Navy">United States Navy</a> began experimenting and implementing the capability to locate the explosion of a <a href="/wiki/SOFAR_bomb" class="mw-redirect" title="SOFAR bomb">SOFAR bomb</a> used as a distress signal by downed pilots. The difference in arrival times of the source at an unknown location and known locations allowed computation of the source's general location.<sup id="cite_ref-HSC-URI_11-2" class="reference"><a href="#cite_note-HSC-URI-11"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> The arrival times form hyperbolic lines of position similar to <a href="/wiki/LORAN" title="LORAN">LORAN</a>. The reverse, detection of timed signals from known shore positions at an unknown point, allowed calculation of the position at that point. That technique was given the name of SOFAR backwards: RAFOS. RAFOS is defined in the 1962 edition of <a href="/wiki/The_American_Practical_Navigator" class="mw-redirect" title="The American Practical Navigator">The American Practical Navigator</a> among the hyperbolic navigation systems.<sup id="cite_ref-HSC-URI_11-3" class="reference"><a href="#cite_note-HSC-URI-11"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> </p><p>The early applications relied on fixed shore stations, often termed SOFAR stations. Several became acoustic research facilities as did the Bermuda SOFAR Station which was involved in the Perth to Bermuda experiment.<sup id="cite_ref-Dushaw_23-1" class="reference"><a href="#cite_note-Dushaw-23"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Northrop_24-1" class="reference"><a href="#cite_note-Northrop-24"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> The records of the Bermuda station are maintained by the <a href="/wiki/Woods_Hole_Oceanographic_Institute" class="mw-redirect" title="Woods Hole Oceanographic Institute">Woods Hole Oceanographic Institute</a> (WHOI).<sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> In the recent past SOFAR sources were deployed for special purposes in the RAFOS application. One such system deployed bottom moored sources off <a href="/wiki/Cape_Hatteras" title="Cape Hatteras">Cape Hatteras</a>, off Bermuda and one on a seamount to send three precisely timed signals a day to provide approximately five-kilometre (3.1 mi; 2.7 nmi) accuracy.<sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> </p><p>The first application quickly became of intense interest to the Navy for reasons other than locating downed air crews. A Navy decision in 1949 led to studies by 1950 recommending the passive sonar potential of the SOFAR channel be exploited for the Navy's Anti-Submarine Warfare (ASW) effort. The recommendation included that $10 million a year be spent on research and development of the system. By 1951 a test array had proven the concept and by 1952 additional stations were ordered for the Atlantic. The first major exploitation of the SOFAR channel was for ocean surveillance in a classified program that led to the <a href="/wiki/SOSUS" title="SOSUS">Sound Surveillance System</a> (SOSUS). That system remained classified from inception until the fixed systems were augmented by mobile arrays to become the Integrated Undersea Surveillance System with the mission and nature of the system declassified in 1991.<sup id="cite_ref-ICAA_8-1" class="reference"><a href="#cite_note-ICAA-8"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-29" class="reference"><a href="#cite_note-29"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>note 5<span class="cite-bracket">]</span></a></sup> </p><p>Earthquake monitoring through the use of SOSUS after limited civilian access was granted to the <a href="/wiki/Pacific_Marine_Environmental_Laboratory" title="Pacific Marine Environmental Laboratory">Pacific Marine Environmental Laboratory</a> (PMEL) of the <a href="/wiki/National_Oceanic_and_Atmospheric_Administration" title="National Oceanic and Atmospheric Administration">National Oceanic and Atmospheric Administration</a> in 1991 revealed ten times the number of offshore earthquakes with better localization than with land-based sensors. The SOSUS detection could sense earthquakes at about magnitude two rather than magnitude four. The system detected seafloor spreading and magma events in the <a href="/wiki/Juan_de_Fuca_Ridge" title="Juan de Fuca Ridge">Juan de Fuca Ridge</a> in time for research vessels to investigate. As a result of that success, PMEL developed its own hydrophones for deployment worldwide to be suspended in the SOFAR channel by a float and anchor system.<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Other_applications">Other applications</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=SOFAR_channel&action=edit&section=3" title="Edit section: Other applications"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Comprehensive_Nuclear-Test-Ban_Treaty_Organization" title="Comprehensive Nuclear-Test-Ban Treaty Organization">Comprehensive Nuclear-Test-Ban Treaty Organization</a> (CTBTO) - International Monitoring System (IMS)<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Missile_Impact_Location_System" title="Missile Impact Location System">Missile Impact Location System</a> (MILS): System to localize impact and location of test missile nose cones<sup id="cite_ref-Cone_6-1" class="reference"><a href="#cite_note-Cone-6"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Ocean_acoustic_tomography" title="Ocean acoustic tomography">Ocean acoustic tomography</a>: A technique to measure ocean temperatures and currents by the time delay of sounds between two distant instruments</li> <li><a href="/wiki/Project_Mogul" title="Project Mogul">Project Mogul</a>, based on the conjectured existence of a similar channel in the <a href="/wiki/Upper_atmosphere" title="Upper atmosphere">upper atmosphere</a></li> <li><a href="/wiki/Search_for_Malaysia_Airlines_Flight_370#Analysis_of_hydroacoustic_data" title="Search for Malaysia Airlines Flight 370">Search for Malaysia Airlines Flight 370</a>: Sounds carried by the SOFAR channel were analyzed to determine if they detected a possible ocean impact of a passenger jet that disappeared in the Southern Indian Ocean</li></ul> <div class="mw-heading mw-heading2"><h2 id="In_nature">In nature</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=SOFAR_channel&action=edit&section=4" title="Edit section: In nature"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Mysterious low-frequency <a href="/wiki/Sound" title="Sound">sounds</a>, attributed to <a href="/wiki/Fin_whale" title="Fin whale">fin whales</a> (<i>Balaenoptera physalus</i>), are a common occurrence in the channel. Scientists believe fin whales may dive down to this channel and sing to communicate with other fin whales many kilometers away.<sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Popular_culture">Popular culture</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=SOFAR_channel&action=edit&section=5" title="Edit section: Popular culture"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The novel <i><a href="/wiki/The_Hunt_for_Red_October" title="The Hunt for Red October">The Hunt for Red October</a></i> describes the use of the SOFAR channel in submarine detection. </p> <div class="mw-heading mw-heading2"><h2 id="Footnotes">Footnotes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=SOFAR_channel&action=edit&section=6" title="Edit section: Footnotes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text">Figure 1 of the reference <a rel="nofollow" class="external text" href="https://docs.google.com/viewer?url=http%3A%2F%2Fbrigus.physics.mun.ca%2F~zedel%2FP6317%2Fpapers%2Fheard_island.pdf">"The Heard Island Feasibility Test"</a> (Munk) shows ray paths to receiving locations. Table 1 lists the sites with one being a Canadian research vessel with a towed array off <a href="/wiki/Cape_Cod" title="Cape Cod">Cape Cod</a>.</span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text">The "History of the SOFAR Channel" reference has a recording and sonogram of the effect.</span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text">The term also has a <a href="/wiki/Critical_depth" title="Critical depth">biological oceanography application</a>.</span> </li> <li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text">Figure 2 on page three of the Williams/Stephen/Smith reference is helpful in understanding critical depth, the SOFAR channel, the entire channel and the ray paths involved.</span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text">It is not entirely coincidental that some of the SOSUS shore facilities, termed Naval Facilities (NAVFAC), were located in the vicinity of older SOFAR stations. For example <a href="/wiki/Naval_Facility_Bermuda" title="Naval Facility Bermuda">Naval Facility Bermuda</a> and <a href="/wiki/Naval_Facility_Point_Sur" title="Naval Facility Point Sur">Naval Facility Point Sur</a>. The local acoustics were already well known.</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=SOFAR_channel&action=edit&section=7" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Bathythermograph" title="Bathythermograph">Bathythermograph</a></li> <li><a href="/wiki/RAFOS_float" title="RAFOS float">RAFOS float</a></li> <li><a href="/wiki/Sofar_bomb" title="Sofar bomb">Sofar bomb</a></li> <li><a href="/wiki/SOSUS" title="SOSUS">Sound Surveillance System (SOSUS)</a></li> <li><a href="/wiki/Underwater_acoustics" title="Underwater acoustics">Underwater acoustics</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=SOFAR_channel&action=edit&section=8" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-NTRP_1-02-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-NTRP_1-02_1-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation book cs1"><a rel="nofollow" class="external text" href="https://apps.dtic.mil/sti/pdfs/ADA562336.pdf"><i>Navy Supplement to the DOD Dictionary of Military and Associated Terms</i></a> <span class="cs1-format">(PDF)</span>. <a href="/wiki/United_States_Navy" title="United States Navy">Department Of The Navy</a>. 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Retrieved <span class="nowrap">26 September</span> 2020</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Oceanus&rft.atitle=Ears+in+the+Ocean&rft.date=2004-08-03&rft.aulast=Smith&rft.aufirst=Deborah+H.&rft_id=https%3A%2F%2Fwww.whoi.edu%2Foceanus%2Ffeature%2Fears-in-the-ocean%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASOFAR+channel" class="Z3988"></span></span> </li> <li id="cite_note-31"><span class="mw-cite-backlink"><b><a href="#cite_ref-31">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDziak2008" class="citation report cs1">Dziak, Bob (August 2008). <a rel="nofollow" class="external text" href="https://pmel.noaa.gov/sites/default/files/atoms/files/oceanacoustics2.pdf">PMEL/Vents Ocean Acoustics</a> <span class="cs1-format">(PDF)</span> (Report). Pacific Marine Environmental Laboratory<span class="reference-accessdate">. Retrieved <span class="nowrap">26 September</span> 2020</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=PMEL%2FVents+Ocean+Acoustics&rft.pub=Pacific+Marine+Environmental+Laboratory&rft.date=2008-08&rft.aulast=Dziak&rft.aufirst=Bob&rft_id=https%3A%2F%2Fpmel.noaa.gov%2Fsites%2Fdefault%2Ffiles%2Fatoms%2Ffiles%2Foceanacoustics2.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASOFAR+channel" class="Z3988"></span></span> </li> <li id="cite_note-32"><span class="mw-cite-backlink"><b><a href="#cite_ref-32">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLawrence2004" class="citation journal cs1">Lawrence, Martin W. (November 2004). <a rel="nofollow" class="external text" href="https://acoustics.asn.au/conference_proceedings/AAS2004/ACOUSTIC/PDF/AUTHOR/AC040084.PDF">"Acoustic Monitoring of the Global Ocean for the CTBT"</a> <span class="cs1-format">(PDF)</span><span class="reference-accessdate">. Retrieved <span class="nowrap">25 September</span> 2020</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Acoustic+Monitoring+of+the+Global+Ocean+for+the+CTBT&rft.date=2004-11&rft.aulast=Lawrence&rft.aufirst=Martin+W.&rft_id=https%3A%2F%2Facoustics.asn.au%2Fconference_proceedings%2FAAS2004%2FACOUSTIC%2FPDF%2FAUTHOR%2FAC040084.PDF&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASOFAR+channel" class="Z3988"></span> <span class="cs1-visible-error citation-comment"><code class="cs1-code">{{<a href="/wiki/Template:Cite_journal" title="Template:Cite journal">cite journal</a>}}</code>: </span><span class="cs1-visible-error citation-comment">Cite journal requires <code class="cs1-code">|journal=</code> (<a href="/wiki/Help:CS1_errors#missing_periodical" title="Help:CS1 errors">help</a>)</span></span> </li> <li id="cite_note-33"><span class="mw-cite-backlink"><b><a href="#cite_ref-33">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://archive.today/20120826003933/http://www3.interscience.wiley.com/journal/119693602/abstract">Orientation by Means of Long Range Acoustic Signaling in Baleen Whales</a>, R. Payne, D. Webb, in Annals NY Acad. Sci., <b>188</b>: 110–41 (1971)</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=SOFAR_channel&action=edit&section=9" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://oceanexplorer.noaa.gov/explorations/sound01/background/acoustics/media/sofar.html">The SOFAR or deep sound channel</a>, from <a href="/wiki/National_Oceanic_and_Atmospheric_Administration" title="National Oceanic and Atmospheric Administration">NOAA</a></li> <li><a rel="nofollow" class="external text" href="https://dosits.org/people-and-sound/examine-the-earth/earthquakes/">How is sound used to study undersea earthquakes?</a> (Recording of the March 11, 2011 Honshu, Japan earthquake recorded at a hydrophone located near the Aleutian Islands)</li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20110718062813/http://www.beyonddiscovery.org/content/view.page.asp?I=224">A sound pipeline</a>, from the <a href="/wiki/United_States_National_Academy_of_Sciences" class="mw-redirect" title="United States National Academy of Sciences">National Academy of Sciences</a></li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20070203040308/http://www.chinfo.navy.mil/navpalib/cno/n87/usw/issue_25/sosus.htm">SOSUS, the "Secret Weapon" of Underwater Surveillance</a> by Edward C. Whitman. <i>Undersea Warfare</i></li> <li><a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=EuhccACOd1U&feature=PlayList&p=DE0461C8581CD884&playnext=1&index=13">Richard Muller, UC Berkeley – lecture on waves, SOFAR and the Roswell UFO Incident</a></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul 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oceanography">Ocean acoustics</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Acoustic_network" title="Acoustic network">Acoustic network</a></li> <li><a href="/wiki/Acoustic_release" title="Acoustic release">Acoustic release</a></li> <li><a href="/wiki/Acoustic_Doppler_current_profiler" title="Acoustic Doppler current profiler">Acoustic Doppler current profiler</a></li> <li><a href="/wiki/Acoustic_seabed_classification" title="Acoustic seabed classification">Acoustic seabed classification</a></li> <li><a href="/wiki/Acoustical_oceanography" class="mw-redirect" title="Acoustical oceanography">Acoustical oceanography</a></li> <li><a href="/wiki/Hydrophone" title="Hydrophone">Hydrophone</a></li> <li><a href="/wiki/Long_baseline_acoustic_positioning_system" title="Long baseline acoustic positioning system">Long baseline acoustic positioning system</a></li> <li><a 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acoustic communication</a></li> <li><a href="/wiki/Underwater_acoustic_positioning_system" title="Underwater acoustic positioning system">Underwater acoustic positioning system</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Acoustic_ecology" title="Acoustic ecology">Acoustic ecology</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Acoustic_survey_in_fishing" title="Acoustic survey in fishing">Acoustic survey in fishing</a></li> <li><a href="/wiki/Acoustic_tag" title="Acoustic tag">Acoustic tag</a></li> <li><a href="/wiki/Animal_echolocation" title="Animal echolocation">Animal echolocation</a></li> <li><a href="/wiki/Beached_whale" class="mw-redirect" title="Beached whale">Beached whale</a></li> <li><a href="/wiki/Deep_scattering_layer" title="Deep scattering layer">Deep scattering layer</a></li> <li><a href="/wiki/Fishfinder" 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MASINT">Geophysical MASINT</a></li> <li><a href="/wiki/Hydrographic_survey" title="Hydrographic survey">Hydrographic survey</a></li> <li><a href="/wiki/Noise_map" title="Noise map">Noise map</a></li> <li><a href="/wiki/Soundscape" title="Soundscape">Soundscape</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Physical_oceanography" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="3"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Physical_oceanography" title="Template:Physical oceanography"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Physical_oceanography" title="Template talk:Physical oceanography"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Physical_oceanography" title="Special:EditPage/Template:Physical oceanography"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Physical_oceanography" style="font-size:114%;margin:0 4em"><a href="/wiki/Physical_oceanography" title="Physical oceanography">Physical oceanography</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Wind_wave" title="Wind wave">Waves</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Airy_wave_theory" title="Airy wave theory">Airy wave theory</a></li> <li><a href="/wiki/Ballantine_scale" title="Ballantine scale">Ballantine scale</a></li> <li><a href="/wiki/Modulational_instability" title="Modulational instability">Benjamin–Feir instability</a></li> <li><a href="/wiki/Boussinesq_approximation_(water_waves)" title="Boussinesq approximation (water waves)">Boussinesq approximation</a></li> <li><a href="/wiki/Breaking_wave" title="Breaking wave">Breaking wave</a></li> <li><a href="/wiki/Clapotis" title="Clapotis">Clapotis</a></li> <li><a href="/wiki/Cnoidal_wave" title="Cnoidal wave">Cnoidal wave</a></li> <li><a href="/wiki/Cross_sea" title="Cross sea">Cross sea</a></li> <li><a href="/wiki/Dispersion_(water_waves)" title="Dispersion (water waves)">Dispersion</a></li> <li><a href="/wiki/Edge_wave" title="Edge wave">Edge wave</a></li> <li><a href="/wiki/Equatorial_wave" title="Equatorial wave">Equatorial waves</a></li> <li><a href="/wiki/Gravity_wave" title="Gravity wave">Gravity wave</a></li> <li><a href="/wiki/Green%27s_law" title="Green's law">Green's law</a></li> <li><a href="/wiki/Infragravity_wave" title="Infragravity wave">Infragravity wave</a></li> <li><a href="/wiki/Internal_wave" title="Internal wave">Internal wave</a></li> <li><a href="/wiki/Iribarren_number" title="Iribarren number">Iribarren number</a></li> <li><a href="/wiki/Kelvin_wave" title="Kelvin wave">Kelvin wave</a></li> <li><a href="/wiki/Kinematic_wave" title="Kinematic wave">Kinematic wave</a></li> <li><a href="/wiki/Longshore_drift" title="Longshore drift">Longshore drift</a></li> <li><a href="/wiki/Luke%27s_variational_principle" title="Luke's variational principle">Luke's variational principle</a></li> <li><a href="/wiki/Mild-slope_equation" title="Mild-slope equation">Mild-slope equation</a></li> <li><a href="/wiki/Radiation_stress" title="Radiation stress">Radiation stress</a></li> <li><a href="/wiki/Rogue_wave" title="Rogue wave">Rogue wave</a></li> <li><a href="/wiki/Rossby_wave" title="Rossby wave">Rossby wave</a></li> <li><a href="/wiki/Rossby-gravity_waves" title="Rossby-gravity waves">Rossby-gravity waves</a></li> <li><a href="/wiki/Sea_state" title="Sea state">Sea state</a></li> <li><a href="/wiki/Seiche" title="Seiche">Seiche</a></li> <li><a href="/wiki/Significant_wave_height" title="Significant wave height">Significant wave height</a></li> <li><a href="/wiki/Soliton" title="Soliton">Soliton</a></li> <li><a href="/wiki/Stokes_drift" title="Stokes drift">Stokes drift</a></li> <li><a href="/wiki/Stokes_problem" title="Stokes problem">Stokes problem</a></li> <li><a href="/wiki/Stokes_wave" title="Stokes wave">Stokes wave</a></li> <li><a href="/wiki/Swell_(ocean)" title="Swell (ocean)">Swell</a></li> <li><a href="/wiki/Trochoidal_wave" title="Trochoidal wave">Trochoidal wave</a></li> <li><a href="/wiki/Tsunami" title="Tsunami">Tsunami</a> <ul><li><a href="/wiki/Megatsunami" title="Megatsunami">megatsunami</a></li></ul></li> <li><a href="/wiki/Undertow_(water_waves)" title="Undertow (water waves)">Undertow</a></li> <li><a href="/wiki/Ursell_number" title="Ursell number">Ursell number</a></li> <li><a href="/wiki/Wave_action_(continuum_mechanics)" title="Wave action (continuum mechanics)">Wave action</a></li> <li><a href="/wiki/Wave_base" title="Wave base">Wave base</a></li> <li><a href="/wiki/Wave_height" title="Wave height">Wave height</a></li> <li><a href="/wiki/Wave_nonlinearity" title="Wave nonlinearity">Wave nonlinearity</a></li> <li><a href="/wiki/Wave_power" title="Wave power">Wave power</a></li> <li><a href="/wiki/Wave_radar" title="Wave radar">Wave radar</a></li> <li><a href="/wiki/Wave_setup" title="Wave setup">Wave setup</a></li> <li><a href="/wiki/Wave_shoaling" title="Wave shoaling">Wave shoaling</a></li> <li><a href="/wiki/Wave_turbulence" title="Wave turbulence">Wave turbulence</a></li> <li><a href="/wiki/Wave%E2%80%93current_interaction" title="Wave–current interaction">Wave–current interaction</a></li> <li><a href="/wiki/Waves_and_shallow_water" title="Waves and shallow water">Waves and shallow water</a> <ul><li><a href="/wiki/One-dimensional_Saint-Venant_equations" class="mw-redirect" title="One-dimensional Saint-Venant equations">one-dimensional Saint-Venant equations</a></li> <li><a href="/wiki/Shallow_water_equations" title="Shallow water equations">shallow water equations</a></li></ul></li> <li><a href="/wiki/Wind_fetch" title="Wind fetch">Wind fetch</a></li> <li><a href="/wiki/Wind_setup" title="Wind setup">Wind setup</a></li> <li><a href="/wiki/Wind_wave" title="Wind wave">Wind wave</a> <ul><li><a href="/wiki/Wind_wave_model" title="Wind wave model">model</a></li></ul></li></ul> </div></td><td class="noviewer navbox-image" rowspan="10" style="width:1px;padding:0 0 0 2px"><div><span typeof="mw:File"><a href="/wiki/File:Upwelling.svg" class="mw-file-description" title="Upwelling"><img alt="Upwelling" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/ee/Upwelling.svg/120px-Upwelling.svg.png" decoding="async" width="120" height="80" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/ee/Upwelling.svg/180px-Upwelling.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/ee/Upwelling.svg/240px-Upwelling.svg.png 2x" data-file-width="365" data-file-height="242" /></a></span><br /><br /><br /><br /><br /><br /><span typeof="mw:File"><a href="/wiki/File:Antarctic_bottom_water.svg" class="mw-file-description" title="Antarctic bottom water"><img alt="Antarctic bottom water" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e7/Antarctic_bottom_water.svg/120px-Antarctic_bottom_water.svg.png" decoding="async" width="120" height="76" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e7/Antarctic_bottom_water.svg/180px-Antarctic_bottom_water.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e7/Antarctic_bottom_water.svg/240px-Antarctic_bottom_water.svg.png 2x" data-file-width="745" data-file-height="470" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Ocean_current" title="Ocean current">Circulation</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Atmospheric_circulation" title="Atmospheric circulation">Atmospheric circulation</a></li> <li><a href="/wiki/Baroclinity" title="Baroclinity">Baroclinity</a></li> <li><a href="/wiki/Boundary_current" title="Boundary current">Boundary current</a></li> <li><a href="/wiki/Coriolis_force" title="Coriolis force">Coriolis force</a></li> <li><a href="/wiki/Coriolis%E2%80%93Stokes_force" title="Coriolis–Stokes force">Coriolis–Stokes force</a></li> <li><a href="/wiki/Craik%E2%80%93Leibovich_vortex_force" title="Craik–Leibovich vortex force">Craik–Leibovich vortex force</a></li> <li><a href="/wiki/Downwelling" title="Downwelling">Downwelling</a></li> <li><a href="/wiki/Eddy_(fluid_dynamics)" title="Eddy (fluid dynamics)">Eddy</a></li> <li><a href="/wiki/Ekman_layer" title="Ekman layer">Ekman layer</a></li> <li><a href="/wiki/Ekman_spiral" title="Ekman spiral">Ekman spiral</a></li> <li><a href="/wiki/Ekman_transport" title="Ekman transport">Ekman transport</a></li> <li><a href="/wiki/El_Ni%C3%B1o%E2%80%93Southern_Oscillation" title="El Niño–Southern Oscillation">El Niño–Southern Oscillation</a></li> <li><a href="/wiki/General_circulation_model" title="General circulation model">General circulation model</a></li> <li><a href="/wiki/Geochemical_Ocean_Sections_Study" title="Geochemical Ocean Sections Study">Geochemical Ocean Sections Study</a></li> <li><a href="/wiki/Geostrophic_current" title="Geostrophic current">Geostrophic current</a></li> <li><a href="/wiki/Global_Ocean_Data_Analysis_Project" title="Global Ocean Data Analysis Project">Global Ocean Data Analysis Project</a></li> <li><a href="/wiki/Gulf_Stream" title="Gulf Stream">Gulf Stream</a></li> <li><a href="/wiki/Humboldt_Current" title="Humboldt Current">Humboldt Current</a></li> <li><a href="/wiki/Hydrothermal_circulation" title="Hydrothermal circulation">Hydrothermal circulation</a></li> <li><a href="/wiki/Langmuir_circulation" title="Langmuir circulation">Langmuir circulation</a></li> <li><a href="/wiki/Longshore_drift" title="Longshore drift">Longshore drift</a></li> <li><a href="/wiki/Loop_Current" title="Loop Current">Loop Current</a></li> <li><a href="/wiki/Modular_Ocean_Model" title="Modular Ocean Model">Modular Ocean Model</a></li> <li><a href="/wiki/Ocean_current" title="Ocean current">Ocean current</a></li> <li><a href="/wiki/Ocean_dynamical_thermostat" title="Ocean dynamical thermostat">Ocean dynamical thermostat</a></li> <li><a href="/wiki/Ocean_dynamics" title="Ocean dynamics">Ocean dynamics</a></li> <li><a href="/wiki/Ocean_gyre" title="Ocean gyre">Ocean gyre</a></li> <li><a href="/wiki/Overflow_(oceanography)" title="Overflow (oceanography)">Overflow</a></li> <li><a href="/wiki/Princeton_Ocean_Model" title="Princeton Ocean Model">Princeton Ocean Model</a></li> <li><a href="/wiki/Rip_current" title="Rip current">Rip current</a></li> <li><a href="/wiki/Subsurface_ocean_current" title="Subsurface ocean current">Subsurface ocean current</a></li> <li><a href="/wiki/Sverdrup_balance" title="Sverdrup balance">Sverdrup balance</a></li> <li><a href="/wiki/Thermohaline_circulation" title="Thermohaline circulation">Thermohaline circulation</a> <ul><li><a href="/wiki/Shutdown_of_thermohaline_circulation" class="mw-redirect" title="Shutdown of thermohaline circulation">shutdown</a></li></ul></li> <li><a href="/wiki/Upwelling" title="Upwelling">Upwelling</a></li> <li><a href="/wiki/Whirlpool" title="Whirlpool">Whirlpool</a></li> <li><a href="/wiki/Wind_generated_current" title="Wind generated current">Wind generated current</a></li> <li><a href="/wiki/World_Ocean_Circulation_Experiment" title="World Ocean Circulation Experiment">World Ocean Circulation Experiment</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Tide" title="Tide">Tides</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Amphidromic_point" title="Amphidromic point">Amphidromic point</a></li> <li><a href="/wiki/Earth_tide" title="Earth tide">Earth tide</a></li> <li><a href="/wiki/Head_of_tide" title="Head of tide">Head of tide</a></li> <li><a href="/wiki/Internal_tide" title="Internal tide">Internal tide</a></li> <li><a href="/wiki/Lunitidal_interval" title="Lunitidal interval">Lunitidal interval</a></li> <li><a href="/wiki/Perigean_spring_tide" title="Perigean spring tide">Perigean spring tide</a></li> <li><a href="/wiki/Rip_tide" title="Rip tide">Rip tide</a></li> <li><a href="/wiki/Rule_of_twelfths" title="Rule of twelfths">Rule of twelfths</a></li> <li><a href="/wiki/Slack_tide" title="Slack tide">Slack tide</a></li> <li><a href="/wiki/Theory_of_tides" title="Theory of tides">Theory of tides</a></li> <li><a href="/wiki/Tidal_bore" title="Tidal bore">Tidal bore</a></li> <li><a href="/wiki/Tidal_force" title="Tidal force">Tidal force</a></li> <li><a href="/wiki/Tidal_power" title="Tidal power">Tidal power</a></li> <li><a href="/wiki/Tidal_race" title="Tidal race">Tidal race</a></li> <li><a href="/wiki/Tidal_range" title="Tidal range">Tidal range</a></li> <li><a href="/wiki/Tidal_resonance" title="Tidal resonance">Tidal resonance</a></li> <li><a href="/wiki/Tide_gauge" title="Tide gauge">Tide gauge</a></li> <li><a href="/wiki/Tideline" title="Tideline">Tideline</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Landform" title="Landform">Landforms</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abyssal_fan" title="Abyssal fan">Abyssal fan</a></li> <li><a href="/wiki/Abyssal_plain" title="Abyssal plain">Abyssal plain</a></li> <li><a href="/wiki/Atoll" title="Atoll">Atoll</a></li> <li><a href="/wiki/Bathymetric_chart" title="Bathymetric chart">Bathymetric chart</a></li> <li><a href="/wiki/Carbonate_platform" title="Carbonate platform">Carbonate platform</a></li> <li><a href="/wiki/Coastal_geography" title="Coastal geography">Coastal geography</a></li> <li><a href="/wiki/Cold_seep" title="Cold seep">Cold seep</a></li> <li><a href="/wiki/Continental_margin" title="Continental margin">Continental margin</a></li> <li><a href="/wiki/Continental_rise" title="Continental rise">Continental rise</a></li> <li><a href="/wiki/Continental_shelf" title="Continental shelf">Continental shelf</a></li> <li><a href="/wiki/Contourite" title="Contourite">Contourite</a></li> <li><a href="/wiki/Guyot" title="Guyot">Guyot</a></li> <li><a href="/wiki/Hydrography" title="Hydrography">Hydrography</a></li> <li><a href="/wiki/Knoll_(oceanography)" title="Knoll (oceanography)">Knoll</a></li> <li><a href="/wiki/Ocean_bank" title="Ocean bank">Ocean bank</a></li> <li><a href="/wiki/Oceanic_basin" title="Oceanic basin">Oceanic basin</a></li> <li><a href="/wiki/Oceanic_plateau" title="Oceanic plateau">Oceanic plateau</a></li> <li><a href="/wiki/Oceanic_trench" title="Oceanic trench">Oceanic trench</a></li> <li><a href="/wiki/Passive_margin" title="Passive margin">Passive margin</a></li> <li><a href="/wiki/Seabed" title="Seabed">Seabed</a></li> <li><a href="/wiki/Seamount" title="Seamount">Seamount</a></li> <li><a href="/wiki/Submarine_canyon" title="Submarine canyon">Submarine canyon</a></li> <li><a href="/wiki/Submarine_volcano" title="Submarine volcano">Submarine volcano</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Plate_tectonics" title="Plate tectonics">Plate<br />tectonics</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Convergent_boundary" title="Convergent boundary">Convergent boundary</a></li> <li><a href="/wiki/Divergent_boundary" title="Divergent boundary">Divergent boundary</a></li> <li><a href="/wiki/Fracture_zone" title="Fracture zone">Fracture zone</a></li> <li><a href="/wiki/Hydrothermal_vent" title="Hydrothermal vent">Hydrothermal vent</a></li> <li><a href="/wiki/Marine_geology" title="Marine geology">Marine geology</a></li> <li><a href="/wiki/Mid-ocean_ridge" title="Mid-ocean ridge">Mid-ocean ridge</a></li> <li><a href="/wiki/Mohorovi%C4%8Di%C4%87_discontinuity" title="Mohorovičić discontinuity">Mohorovičić discontinuity</a></li> <li><a href="/wiki/Oceanic_crust" title="Oceanic crust">Oceanic crust</a></li> <li><a href="/wiki/Outer_trench_swell" title="Outer trench swell">Outer trench swell</a></li> <li><a href="/wiki/Ridge_push" title="Ridge push">Ridge push</a></li> <li><a href="/wiki/Seafloor_spreading" title="Seafloor spreading">Seafloor spreading</a></li> <li><a href="/wiki/Slab_pull" title="Slab pull">Slab pull</a></li> <li><a href="/wiki/Slab_suction" title="Slab suction">Slab suction</a></li> <li><a href="/wiki/Slab_window" title="Slab window">Slab window</a></li> <li><a href="/wiki/Subduction" title="Subduction">Subduction</a></li> <li><a href="/wiki/Transform_fault" title="Transform fault">Transform fault</a></li> <li><a href="/wiki/Vine%E2%80%93Matthews%E2%80%93Morley_hypothesis" title="Vine–Matthews–Morley hypothesis">Vine–Matthews–Morley hypothesis</a></li> <li><a href="/wiki/Volcanic_arc" title="Volcanic arc">Volcanic arc</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Ocean zones</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Benthic_zone" title="Benthic zone">Benthic</a></li> <li><a href="/wiki/Deep_ocean_water" title="Deep ocean water">Deep ocean water</a></li> <li><a href="/wiki/Deep_sea" title="Deep sea">Deep sea</a></li> <li><a href="/wiki/Littoral_zone" title="Littoral zone">Littoral</a></li> <li><a href="/wiki/Mesopelagic_zone" title="Mesopelagic zone">Mesopelagic</a></li> <li><a href="/wiki/Oceanic_zone" title="Oceanic zone">Oceanic</a></li> <li><a href="/wiki/Pelagic_zone" title="Pelagic zone">Pelagic</a></li> <li><a href="/wiki/Photic_zone" title="Photic zone">Photic</a></li> <li><a href="/wiki/Surf_zone" title="Surf zone">Surf</a></li> <li><a href="/wiki/Swash" title="Swash">Swash</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Sea_level" title="Sea level">Sea level</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Deep-ocean_Assessment_and_Reporting_of_Tsunamis" title="Deep-ocean Assessment and Reporting of Tsunamis">Deep-ocean Assessment and Reporting of Tsunamis</a></li> <li><a href="/wiki/Global_Sea_Level_Observing_System" title="Global Sea Level Observing System">Global Sea Level Observing System</a></li> <li><a href="/wiki/North_West_Shelf_Operational_Oceanographic_System" title="North West Shelf Operational Oceanographic System">North West Shelf Operational Oceanographic System</a></li> <li><a href="/wiki/Sea-level_curve" title="Sea-level curve">Sea-level curve</a></li> <li><a href="/wiki/Sea_level_drop" title="Sea level drop">Sea level drop</a></li> <li><a href="/wiki/Sea_level_rise" title="Sea level rise">Sea level rise</a></li> <li><a href="/wiki/World_Geodetic_System" title="World Geodetic System">World Geodetic System</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Acoustical_oceanography" class="mw-redirect" title="Acoustical oceanography">Acoustics</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Deep_scattering_layer" title="Deep scattering layer">Deep scattering layer</a></li> <li><a href="/wiki/Ocean_acoustic_tomography" title="Ocean acoustic tomography">Ocean acoustic tomography</a></li> <li><a href="/wiki/Sofar_bomb" title="Sofar bomb">Sofar bomb</a></li> <li><a class="mw-selflink selflink">SOFAR channel</a></li> <li><a href="/wiki/Underwater_acoustics" title="Underwater acoustics">Underwater acoustics</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Satellites</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Jason-1" title="Jason-1">Jason-1</a></li> <li><a href="/wiki/OSTM/Jason-2" title="OSTM/Jason-2">OSTM/Jason-2</a></li> <li><a href="/wiki/Jason-3" title="Jason-3">Jason-3</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ocean_acidification" title="Ocean acidification">Acidification</a></li> <li><a href="/wiki/Argo_(oceanography)" title="Argo (oceanography)">Argo</a></li> <li><a href="/wiki/Benthic_lander" title="Benthic lander">Benthic lander</a></li> <li><a href="/wiki/Color_of_water" title="Color of water">Color of water</a></li> <li><a href="/wiki/DSV_Alvin" title="DSV Alvin">DSV <i>Alvin</i></a></li> <li><a href="/wiki/Marginal_sea" class="mw-redirect" title="Marginal sea">Marginal sea</a></li> <li><a href="/wiki/Marine_energy" title="Marine energy">Marine energy</a></li> <li><a href="/wiki/Marine_pollution" title="Marine pollution">Marine pollution</a></li> <li><a href="/wiki/Mooring_(oceanography)" title="Mooring (oceanography)">Mooring</a></li> <li><a href="/wiki/National_Oceanographic_Data_Center" title="National Oceanographic Data Center">National Oceanographic Data Center</a></li> <li><a href="/wiki/Ocean" title="Ocean">Ocean</a></li> <li><a href="/wiki/Ocean_exploration" title="Ocean exploration">Explorations</a></li> <li><a href="/wiki/Ocean_observations" title="Ocean observations">Observations</a></li> <li><a href="/wiki/Ocean_reanalysis" title="Ocean reanalysis">Reanalysis</a></li> <li><a href="/wiki/Ocean_surface_topography" title="Ocean surface topography">Ocean surface topography</a></li> <li><a href="/wiki/Ocean_temperature" title="Ocean temperature">Ocean temperature</a></li> <li><a href="/wiki/Ocean_thermal_energy_conversion" title="Ocean thermal energy conversion">Ocean thermal energy conversion</a></li> <li><a href="/wiki/Oceanography" title="Oceanography">Oceanography</a> <ul><li><a href="/wiki/Outline_of_oceanography" title="Outline of oceanography">Outline of oceanography</a></li></ul></li> <li><a href="/wiki/Pelagic_sediment" title="Pelagic sediment">Pelagic sediment</a></li> <li><a href="/wiki/Sea_surface_microlayer" title="Sea surface microlayer">Sea surface microlayer</a></li> <li><a href="/wiki/Sea_surface_temperature" title="Sea surface temperature">Sea surface temperature</a></li> <li><a href="/wiki/Seawater" title="Seawater">Seawater</a></li> <li><a href="/wiki/Science_On_a_Sphere" title="Science On a Sphere">Science On a Sphere</a></li> <li><a href="/wiki/Ocean_stratification" title="Ocean stratification">Stratification</a></li> <li><a href="/wiki/Thermocline" title="Thermocline">Thermocline</a></li> <li><a href="/wiki/Underwater_glider" title="Underwater glider">Underwater glider</a></li> <li><a href="/wiki/Water_column" title="Water column">Water column</a></li> <li><a href="/wiki/World_Ocean_Atlas" title="World Ocean Atlas">World Ocean 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