Fixed-point ocean observatory

<h2 id="infrastructure">Infrastructure</h2>
<p>Fixed-point ocean observatories are typically composed of a cable anchored to the sea floor to which several automatic sensors and samplers are attached. The cable ends with a buoy at the ocean surface that may have some more sensors attached.<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a> Most observatories have communicating buoys that transmit data to shore, and which allow changes to the acquisition method of the sensors, as required.
</p><p>These unmanned platforms can be linked via a cable to the shore transmitting data via an <a href="/facts/Internet/Xw1rVvJU">internet</a> connection, or they can transmit data to <a href="/facts/Relay/NQcb9usW">relay</a> buoys which are able to provide a <a href="/facts/Satellite/PTX8c68t">satellite</a> link to the shore.
</p><p>An example for a network of observatories is the <a href="/facts/Ocean_Observatories_Initiative/T9Cy8MtV">Ocean Observatories Initiative</a>.
</p>
<h2 id="instrumentation">Instrumentation</h2>
<p>A typical <a href="/facts/Multi-disciplinary/HP0uaNUs">multi-disciplinary</a> observatory is equipped with sensors and instruments to measure physical and biogeochemical variables along the water column. Additionally the surface buoy can hold several sensors measuring atmospheric parameters at sea level.<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a> 
Main measured variables:
</p>
<table><tbody><tr><td>Sea surface</td><td><p><a href="/facts/Sea_surface_temperature/D9bNcRxX">Sea-surface temperature</a> (SST)<a href="/facts/Salinity/X6mB1YAM">Sea-surface salinity</a> (SSS)<a href="/facts/Sea_level/mDhuI7Xe">Sea level</a><a href="/facts/Sea_state/eIGaYdlJ">Sea state</a><a href="/facts/Sea_ice/tgTbCYwg">Sea ice</a><a href="/facts/Ocean_current/vfwdGwPY">Current</a><a href="/facts/Ocean_colour/4Wuh5PN8">Ocean colour</a> (for biological activity)<a href="/facts/Carbon_dioxide_partial_pressure/xGzpppEp">Carbon dioxide partial pressure</a> (pCO2)<a href="/facts/Dissolved_oxygen/UVhwuc26">Dissolved oxygen</a></p></td></tr><tr><td>Sub-surface</td><td><p>TemperatureSalinityCurrentNutrientsCarbonOcean tracersPhytoplanktonTurbidityPressure (used to measure depth)</p></td></tr><tr><td>Atmosphere (Surface)</td><td><p>Air TemperatureAtmosphere Pressure at Sea LevelRelative HumidityWind SpeedWind DirectionSolar Radiation</p></td></tr></tbody></table>
<p>In order to do so, typically the ocean observatories are equipped with instruments like:
</p>
<ul><li><a href="/facts/Acoustic_Doppler_current_profiler/dN5GY6tK">ADCP</a> – Acoustic Doppler current profiler, to measure <a href="/facts/Ocean_current/vfwdGwPY">currents</a>;</li>
<li><a href="/facts/CTD_(instrument)/6SIDLetS">CTD</a> (conductivity, temperature and depth) sensors, to measure <a href="/facts/Salinity/X6mB1YAM">conductivity</a> and thermal variations at a known depth;</li>
<li><a href="/facts/Hydrophone/yLwe7VYY">Hydrophone</a> – to record sounds;</li>
<li><a href="/facts/Sediment_trap/JogH9TP3">Sediment Trap</a> – to quantify the quantity of sinking material;</li>
<li>Deep sea <a href="/facts/Camera/j4uqsfJQ">camera</a> – to capture footage on location;</li>
<li><a href="/facts/Seismometer/CCc9vwqf">Seismometer</a> – to record the earth motion;</li>
<li><a href="/facts/Carbon_dioxide/xGzpppEp">CO2</a> analyser – to measure CO2;</li>
<li><a href="/facts/Dissolved_Oxygen/UVhwuc26">Dissolved Oxygen</a> sensor – to measure dissolved oxygen;</li>
<li><a href="/facts/Fluorometer/sN4Hq9Uu">Fluorometers</a> – to measure <a href="/facts/Chlorophyll/1Sb0NyyM">Chlorophyll</a>;</li>
<li><a href="/facts/Turbidity/aqPf0q3I">Turbidity</a> sensor – to measure turbidity.</li></ul>
<h2 id="purpose">Purpose</h2>
<p>Ocean observatories can collect data for different purposes from scientific research to <a href="/facts/Environmental_monitoring/ScUSz2ga">environmental monitoring</a> for marine operations or governance for the benefit of economy and society as a whole.
Ocean observatories provide real-time, or near real time data allowing to detect changes as they happen, such as geo-hazards for example. Furthermore continuous time series data allow to investigate interannual-to-decadal changes and to capture episodic events, changes in ocean circulation, water properties, water mass formation and ecosystems, to quantify air-sea fluxes, and to analyse the role of the oceans for the climate.
</p><p>The data collected by the several ocean observatories around the globe on the sub-sea-floor, seafloor, and water column, allows to improve our knowledge<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a> of the ocean including:
</p>
<ol><li>Ocean physics and <a href="/facts/Climate_change/rEN4BDE7">climate change</a></li>
<li>Biodiversity and ecosystem assessment</li>
<li><a href="/facts/Carbon_cycle/gVusRaPF">Carbon cycle</a> and ocean acidification</li>
<li>Geophysics and geodynamics</li></ol>
<p>Moreover  networks of ocean observatories can also be used to input data into global ocean models and to calibrate them thus allowing for the investigation of future changes in ocean circulation and ecosystems.
</p>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/VENUS/GC9FlrYe">VENUS</a> Canada, an ocean observatory operated by <a href="/facts/Ocean_Networks_Canada/DNyGQl1D">Ocean Networks Canada</a>.</li>
<li><a href="/facts/NEPTUNE/lodmyybC">NEPTUNE</a> Canada, a sister observatory to VENUS, also operated by Ocean Networks Canada.</li>
<li><a href="/facts/MARS_(oceanography)/LgWIKjzf">MARS</a>, a similar <a href="/facts/MBARI/tX5aF0Te">MBARI</a> cabled-based oceanography observatory.</li>
<li>SATURN, Science and Technology University Research Network, a coastal margin, or river-to-ocean, testbed observatory for the United States Pacific Northwest, a project of the National Science Foundation Science and Technology Center for Coastal Margin Observation and Prediction.</li>
<li><a href="/facts/Ocean_development/o8JIRjGr">Ocean development</a></li></ul>

<h2 id="external-links">External links</h2>
<ul><li><a href="https://www.jerico-ri.eu/">JERICO-NEXT Project (Joint European Research Infrastructure network for Coastal Observatories)</a></li>
<li><a href="https://emso.eu/">European Multidisciplinary Seafloor and water-column Observatory</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>FixO3 Project Factsheet http://www.fixo3.eu/ <a href="http://www.fixo3.eu/" target="_blank">http://www.fixo3.eu/</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>Ruhl, Henry A.; André, Michel; Beranzoli, Laura; Çağatay, M. Namik; Colaço, Ana; Cannat, Mathilde; Dañobeitia, Juanjo J.; Favali, Paolo; Géli, Louis; Gillooly, Michael; Greinert, Jens; Hall, Per O.J.; Huber, Robert; Karstensen, Johannes; Lampitt, Richard S. (2011). "Societal need for improved understanding of climate change, anthropogenic impacts, and geo-hazard warning drive development of ocean observatories in European Seas" (PDF). Progress in Oceanography. 91 (1): 1–33. doi:10.1016/j.pocean.2011.05.001. <a href="http://archimer.ifremer.fr/doc/00044/15557/15923.pdf" target="_blank">http://archimer.ifremer.fr/doc/00044/15557/15923.pdf</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>Favali, Paolo; Beranzoli, Laura; De Santis, Angelo (2015). SEAFLOOR OBSERVATORIES: A New Vision of the Earth from the Abyss. Berlin, Heidelberg: Springer Berlin Heidelberg. doi:10.1007/978-3-642-11374-1. ISBN 978-3-642-11373-4. <a href="978-3-642-11373-4" target="_blank">978-3-642-11373-4</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
</ol>

Fixed-point ocean observatory open-in-new

Fixed-point ocean observatory