Editing Physical oceanography (section)

== Physical setting ==
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|image1=[http://www-po.coas.oregonstate.edu/intro/pofig.html Space and time scales of physical oceanographic processes.]<ref>[http://www-po.coas.oregonstate.edu/intro/ Physical Oceanography] {{webarchive|url=https://archive.today/20120717064415/http://www-po.coas.oregonstate.edu/intro/ |date=2012-07-17 }} Oregon State University.</ref>
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[[Image:Atlantic-trench.JPG|thumb|right|210px|Perspective view of the sea floor of the Atlantic Ocean and the Caribbean Sea. The purple sea floor at the center of the view is the [[Puerto Rico Trench]].]]

Roughly 97% of the planet's water is in its oceans, and the oceans are the source of the vast majority of [[water vapor]] that condenses in the atmosphere and falls as [[rain]] or [[snow]] on the continents.<ref name="Pinet1996">{{cite book |title=Invitation to Oceanography |last=Pinet |first=Paul R. |year=1996 |publisher=West Publishing Co. |edition=3rd |location=St. Paul, MN |isbn=0-7637-2136-0 |url-access=registration |url=https://archive.org/details/invitationtoocea0000pine_i9f0 }}</ref><ref name="Hamblin1998">{{cite book |title=Earth's Dynamic Systems |last=Hamblin |first=W. Kenneth |author2=Christiansen, Eric H. |year=1998 |edition=8th |publisher=Prentice-Hall |location=Upper Saddle River |isbn=0-13-018371-7 }}</ref> The tremendous [[heat capacity]] of the oceans moderates the planet's [[climate]], and its absorption of various gases affects the composition of the [[atmosphere]].<ref name="Hamblin1998" /> The ocean's influence extends even to the composition of [[volcano|volcanic]] rocks through seafloor [[metamorphic rocks|metamorphism]], as well as to that of volcanic gases and [[magma]]s created at [[subduction zones]].<ref name="Hamblin1998" />

From sea level, the oceans are far deeper than the [[continent]]s are tall; examination of the Earth's [[hypsographic curve]] shows that the average elevation of Earth's landmasses is only {{convert|840|m|ft}}, while the ocean's average depth is {{convert|3800|m|ft}}. Though this apparent discrepancy is great, for both land and sea, the respective extremes such as [[mountains]] and [[trenches]] are rare.<ref name="Pinet1996" />

{|
|+ Area, volume plus mean and maximum depths of oceans (excluding adjacent seas)
|-
| '''Body'''
| '''Area''' (10<sup>6</sup>km<sup>2</sup>)
| '''Volume''' (10<sup>6</sup>km<sup>3</sup>)
| '''Mean depth''' (m)
| '''Maximum''' (m)
|-
| [[Pacific Ocean]]
| 165.2
| 707.6
| 4282
| -11033
|-
| [[Atlantic Ocean]]
| 82.4
| 323.6
| 3926
| -8605
|-
| [[Indian Ocean]]
| 73.4
| 291.0
| 3963
| -8047
|-
| [[Southern Ocean]]
| 20.3
|
|
| -7235
|-
| [[Arctic Ocean]]
| 14.1
|
| 1038
|
|-
| [[Caribbean Sea]]
| 2.8
|
|
| -7686
|}