Ocean

{{bronze}}{{Geology}}
'''Oceans''' are big wet blue things that cover quite a lot of the earth. They are very salty, extremely polluted and contain many delicious edibles.

==History==
[[File:Pic cheshire01-big.jpg|thumb|A salt mine reveals the massive deposits left behind by the evaporation of former seas million of years ago.]]
Oceans formed over the course of [[geologic timeline | millions of years]] after the shiny new Earth cooled enough for [[water]] to settle on its surface and to fill up the shallower bits. As the [[continental drift | crust drifted about]], continents and supercontinents formed and re-formed; the spaces in between these land masses would become individual seas. [[Pangaea]], the most recently-formed of the supercontinents, split up between 250 and 150 million years ago,{{efn|This is the duration of various phases of breaking up, not a ridiculous uncertainty. After all, drift is slow, you don't wake up to find the Earth completely resurfaced overnight!}} dividing the large Tethys ocean<ref>{{wpa | Tethys Ocean}}</ref> into several smaller oceans. The '''Atlantic Ocean''' is the youngest of these; as measured by the record of changes in the magnetic field in the rocks below it &mdash; it is thought to date back less than a hundred million years.

In historic times, the oceans posed an insurmountable barrier to most [[culture]]s.  During the [[Middle Ages]], better shipbuilding techniques finally enabled regular and relatively safe crossings. As a result, five or six small countries on the northeastern Atlantic coast<ref>Portugal, Spain, France, the Netherlands, Britain; plus optionally Denmark. Or Sweden. Or Courland. Plus maybe Belgium.</ref> succeeded in carving up most of the world into a few massive "sea-borne" empires, the consequences of which remain readily apparent today.

According to some [[Young-Earthers]], the amount of [[salt]] in the oceans suggests that seas formed up to 62 million years ago.<ref>[http://creation.com/age-of-the-earth A young Earth indeed.] - "Even ignoring the effect of the biblical Flood and assuming zero starting salinity and all rates of input and removal so as to maximize the time taken to accumulate all the salt, the maximum age of the oceans, 62 million years, is less than 1/50 of the age evolutionists claim for the oceans. This suggests that the age of the earth is radically less also.</ref><ref>
[https://creation.com/salty-seas-evidence-for-a-young-earth Estimating the ocean’s age] - "Granting the most generous assumptions to evolutionists, Austin and Humphreys calculated that the ocean must be less than 62 million years old. It's important to stress that this is not the actual age, but a maximum age. That is, this evidence is consistent with any age up to 62 million years, including the biblical age of about 6,000 years."
</ref>
The Young-Earthers make their argument based on a starting point of zero salt. False assumption &mdash; the oceans actually once had more salt than they have today. This is due to the fact that a large amount of salt is deposited on the shore when seawater evaporates outside of the ocean &mdash; the first great lowering of salinity occurred in the late [[Precambrian]] - 1 billion to 541 million years ago - when huge amounts of salt were deposited in Neoproterozoic evaporite basins. These deposits result in a mineral known as "evaporite".<ref>
[http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V6R-4F4NYHS-2&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=d17b18e69eef609f591968a4f71f818c ScienceDirect]
</ref> 
If you like bikes, you'll ''love'' the long-term global '''ocean salinity cycle'''.<ref>
{{cite book
 |last1                = Durack
 |first1               = Paul J
 |last2                = Wijffels
 |first2               = Susan E.
 |author-link2         = Susan Wijffels
 |last3                = Boyer
 |first3               = Tim P.
 |editor-last1         = Siedler
 |editor-first1        = Gerold
 |editor-link1         = Gerold Siedler
 |editor-last2         = Griffies
 |editor-first2        = Stephen M.
 |editor-last3         = Gould
 |editor-first3        = John
 |editor-last4         = Church
 |editor-first4        = John A.
 |chapter              = 28. Long-term Salinity Changes and Implications for the Global Water Cycle
 |title                = Ocean Circulation and Climate
 |url                  = https://www.google.com/books?id=Ew51DAAAQBAJ
 |series               = International Geophysics Series Volume 103
 |publisher            = Elsevier Inc.
 |publication-date     = 2013
 |isbn                 = 9780128058770
 |access-date          = 23 January 2022
 |quote                = Long-term global ocean salinity variation provides an insight into water cycle change.
}} 
</ref>

In other evidence for the extreme age of the oceans, not long after they formed, [[iron]]-manganese nodules started forming, incredibly slowly: see [[Evidence against a recent creation#Iron-manganese nodule growth: >1,000,000|here]] for more information.

==Life==
[[File:80499_marianatrench.jpg|thumb|left|250x350px|Lovecraftian Horror]]
The greatest ''variety'' of life occurs in coral reefs, but the vast open ocean has the most ''productivity''. 

There are plenty of fish in the sea - the oceans contain more than (insert really big number here) species.  They also teem with plant life and invertebrate animals, and many species of aquatic mammal, including [[dolphin]]s and whales.  Most of the ''really'' weird stuff, however, is in the deep sea trenches.<ref>[http://www.greenpeace.org/download/windowsmedia/international/photosvideos/videos/deep-sea-creatures/Deep_sea_creat_VF_WinMedia_.wmv Weird stuff. From Greenpeace. It's just a video, so just open it.]</ref> The deepest recorded sea trench is the Mariana Trench which is thought to be roughly just under 11,000 m, or about 36,000 ft.

==Non-conservation==

The oceans have also provided food for seagoing communities (a resource currently being depleted faster than it can be replaced), and are also used as a huge rubbish dump. Both of these may well have a permanent effect on sea life &mdash; it is possible that jellyfish may become the sea's dominant life form after all the fish have been eaten or choke on plastic bags.<ref>{{cite web | last=McKee | first=Linda | title=Invasion of the jellyfish: They could take over our seas, say wildlife experts | website=belfasttelegraph.co.uk | date=2009-03-31 | url=https://www.belfasttelegraph.co.uk/news/environment/invasion-of-the-jellyfish-they-could-take-over-our-seas-say-wildlife-experts-14249899.html | archive-url=https://web.archive.org/web/20090403175429/https://www.belfasttelegraph.co.uk/news/environment/invasion-of-the-jellyfish-they-could-take-over-our-seas-say-wildlife-experts-14249899.html | archive-date=2009-04-03 | url-status=dead | access-date=2025-12-11}}</ref>

Whales are probably the most famous example of overfishing (overmammaling?). The result is this:

<table border="1" cellpadding="2" cellspacing="0">

<tr>

<th>
Extinct
</th>

<th>
Critically Endangered
</th>

<th>
Endangered
</th>

<th>
Vulnerable
</th>

<th>
Lower Risk <br>
(Conservation Dependent)
</th>

<th>
Lower risk <br>
(Near Threatened)
</th>

<th>
Lower Risk <br>
(Least Concern)
</th>
</tr>

<tr valign="top">

<td>
None*

<td>
* Blue whale <br>(Antarctic)<ref>http://www.iucnredlist.org/search/details.php/41713/all</ref>
* Gray whale <br>(Northwest Pacific)<ref>http://www.iucnredlist.org/search/details.php/8099/all</ref>

</td>

<td>
* Blue whale<ref>http://www.iucnredlist.org/details/2477</ref>
* Fin whale<ref>http://www.iucnredlist.org/search/details.php/2478/summ</ref>
* North Pacific right whale<ref>http://www.iucnredlist.org/search/details.php/41711/summ</ref>
* North Atlantic right whale<ref>http://www.iucnredlist.org/search/details.php/41712/summ</ref>
* Sei whale<ref>http://www.iucnredlist.org/search/details.php/2475/summ</ref>
</td>

<td>
* Beluga<ref>http://www.iucnredlist.org/search/details.php/6335/summ</ref>
* Blue whale<br>''musculus ''subspecies (Atlantic)<ref>http://www.iucnredlist.org/search/details.php/2483/all</ref>
* Sperm whale<ref>http://www.iucnredlist.org/search/details.php/41755/summ</ref>
</td>

<td>
* Antarctic minke whale
* Arnoux's beaked whale
* Baird's beaked whale
* Blue whale (North Pacific)<ref>http://www.iucnredlist.org/search/details.php/2482/all</ref>
* Bowhead whale<ref>http://www.iucnredlist.org/search/details.php/2467/summ</ref>
* Gray whale<br>(Northeast Pacific)<ref>http://www.iucnredlist.org/search/details.php/8098/all</ref>
* Northern bottlenose whale
* Southern bottlenose whale
* Short-finned pilot whale
* Southern right whale<ref>http://www.iucnredlist.org/search/details.php/8153/summ</ref>
</td>

<td>

</td>

<td>
* Minke whale<ref name="cmsdata.iucn.org">http://cmsdata.iucn.org/downloads/cetacean_table_for_website.pdf</ref>
* Dwarf sperm whale<ref>http://www.iucnredlist.org/search/details.php/11048/summ</ref>
* Pygmy right whale
* Long-finned pilot whale
* Humpback whale<ref>http://www.iucnredlist.org/search/details.php/13006/summ</ref>
* Pygmy sperm whale<ref>http://www.iucnredlist.org/search/details.php/11047/summ</ref>
* Melon-headed whale
* Gray whale (species)<ref name="cmsdata.iucn.org"/>
</td>
</tr>
</table>
<nowiki>*</nowiki> The Atlantic population of gray whales went extinct in the late-17<sup>th</sup> century. It is not listed as a part of IUCN's red list.<ref name="IUCNredGray">[http://www.iucnredlist.org/details/8097 Eschrichtius robustus (Grey whale) Geographic Range] IUCN Red list of threatened species</ref>

Despite the mess whaling made of the marine mammal population, people still do it (even though commercial whaling is banned by international law). As of 1987, [[Japan]] has been whaling for "scientific purposes", which apparently include distributing the meat of what may be the second most intelligent species on Earth to school children for lunch, and (one can safely assume) resurrecting commercial whaling.<ref>[http://www.greenpeace.org/usa/campaigns/oceans/whale-defenders/whaling-101 Greenpeace]</ref>

==Relevance to global warming==
{{main|climate change}}
Oceans store 90% of the "additional" energy retained by the greenhouse effect. Even years that are not "hottest on record" for surface temperature changes tend to be "hottest on record" for the oceans.<ref name="advances">Advances in Atmospheric Science [https://link.springer.com/article/10.1007%2Fs00376-019-8276-x 2018 Continues Record Global Ocean Warming]</ref> In addition to this, sea level rises and ocean acidification are among the most prominent and damaging long-term consequences of unchecked climate change.

==Sea also==
*[[Shark]]
*[[Bermuda Triangle]]

==Notes==
{{reflist|group=note}}

==References==
{{reflist|2|80%}}

[[Category:Science]]
[[Category:Environmentalism]]
[[Category:Geology]]
[[Category:Global warming]]

Categories: Science, Environmentalism, Geology, Global warming