Editing Atoll (section)

== Distribution and size ==
There are approximately 440 atolls in the world.<ref name="Watts2019">{{cite journal|title=Science, Seamounts and Society |author=Watts, T. |journal=Geoscientist |year=2019 |volume=August 2019 |pages=10–16}}</ref> Most of the world's atolls are in the Pacific Ocean (with concentrations in the [[Caroline Islands]], the [[Coral Sea Islands]], the [[Marshall Islands]], the [[Tuamotu Islands]], [[Kiribati]], [[Tokelau]], and [[Tuvalu]]) and the [[Indian Ocean]] (the [[Chagos Archipelago]], [[Lakshadweep]], the [[atolls of the Maldives]], and the [[Outer Islands (Seychelles)|Outer Islands]] of [[Seychelles]]). In addition, Indonesia also has several atolls spread across the archipelago, such as in the [[Thousand Islands (Indonesia)|Thousand Islands]], [[Taka Bonerate Islands]], and atolls in the [[Raja Ampat Islands]]. The Atlantic Ocean has no large groups of atolls, other than eight atolls east of [[Nicaragua]] that belong to the [[Colombia]]n department of [[Archipelago of San Andrés, Providencia and Santa Catalina|San Andres and Providencia]] in the Caribbean.

Reef-building corals will thrive only in warm [[tropics|tropical]] and [[subtropics|subtropical]] waters of oceans and seas, and therefore atolls are found only in the tropics and subtropics. The northernmost atoll in the world is [[Kure Atoll]] at 28°25′ N, along with other atolls of the [[Northwestern Hawaiian Islands]]. The southernmost atolls in the world are [[Elizabeth Reef]] at 29°57′ S, and nearby [[Middleton Reef]] at 29°27′ S, in the [[Tasman Sea]], both of which are part of the [[Coral Sea Islands]] Territory. The next southerly atoll is [[Ducie Island]] in the [[Pitcairn Islands]] Group, at 24°41′ S. 
The atoll closest to the Equator is [[Aranuka]] of Kiribati. Its southern tip is just {{cvt|13|km|sigfig=1}} north of the Equator.

[[Bermuda]] is sometimes claimed as the "northernmost atoll" at a [[latitude]] of 32°18′ N. At this latitude, coral reefs would not develop without the warming waters of the [[Gulf Stream]]. However, Bermuda is termed a ''[[pseudo-atoll]]'' because its general form, while resembling that of an atoll, has a very different origin of formation.

In most cases, the land area of an atoll is very small in comparison to the total area. Atoll islands are low lying, with their elevations less than {{convert|5|m|ft}}. Measured by total area, [[Lifou]] ({{cvt|1146|km2|disp=comma}}) is the largest [[raised coral atoll]] of the world, followed by [[Rennell Island]] ({{cvt|660|km2|disp=comma}}).<ref>{{cite web |url=http://www.worldislandinfo.com/MISINFORMATION.htm |title=Misinformation about Islands |publisher=worldislandinfo.com}}</ref> More sources, however, list [[Kiritimati]] as the largest atoll in the world in terms of land area. It is also a raised coral atoll ({{cvt|321|km2|disp=comma}} land area; according to other sources even {{cvt|575|km2|disp=comma}}), {{cvt|160|km2}} main lagoon, {{cvt|168|km2}} other lagoons (according to other sources {{cvt|319|km2|disp=comma}} total lagoon size).

The geological formation known as a [[reef knoll]] refers to the elevated remains of an ancient atoll within a limestone region, appearing as a hill. The second largest atoll by dry land area is [[Aldabra]], with {{cvt|155|km2}}. [[Huvadhu Atoll]], situated in the southern region of the Maldives, holds the distinction of being the largest atoll based on the sheer number of islands it comprises, with a total of 255 individual islands.

[[File:On the structure and distribution of coral reefs BHL40453231.jpg|thumb|upright=3|center|Map from [[Charles Darwin]]'s 1842 ''[[The Structure and Distribution of Coral Reefs]]'' showing the world's major groups of atolls and coral reefs]]

===List of atolls===
{| class="wikitable plainrowheaders sortable static-row-numbers sort-under col1right"
|+ style="padding-bottom: 0.5em" | Largest atolls by total area (lagoon plus reef and dry land)<ref>{{Cite FTP |url = ftp://rock.geosociety.org/pub/reposit/2001/2001075.pdf |title = Atoll Area, Depth and Rainfall|date = 2001|server = The Geological Society of America |url-status = dead |format= spreadsheet }}</ref>
|-
! scope="col" | Name
! scope="col" | Position
! scope="col" | Location
! scope="col" style="max-width: 4em;" | Land area (km<sup>2</sup>)
! scope="col" style="max-width: 4em;" | Total area (km<sup>2</sup>)
! scope="col" | Notes
|-
! scope="row" | [[Great Chagos Bank]]
| {{Coord|-6.17|72.00|display=inline}}
| [[Indian Ocean]]
| style="text-align: right;" | 4.5
| style="text-align: right;" | 12,642
| 
|-
! scope="row" | Reed Bank
| {{Coord|11.45|116.90|display=inline}}
| [[Spratly Islands]]
| style="text-align: right;" |
| style="text-align: right;" | 8,866
| Submerged, at shallowest 9 m
|-
! scope="row" | [[Macclesfield Bank]]
| {{Coord|16.00|114.50|display=inline}}
| [[South China Sea]]
| style="text-align: right;" |
| style="text-align: right;" | 6,448
| Submerged, at shallowest 9.2 m
|-
! scope="row" | North Bank
| {{Coord|-9.07|60.20|display=inline}}
| North of [[Saya de Malha Bank]]
| style="text-align: right;" |
| style="text-align: right;" | 5,800
| Submerged, at shallowest <10 m
|-
! scope="row" | [[Rosalind Bank]]
| {{Coord|16.43|-80.52|display=inline}}
| [[Caribbean]]
| style="text-align: right;" |
| style="text-align: right;" | 4,500
| Submerged, at shallowest 7.3 m
|-
! scope="row" | [[Thiladhunmathi]]
| {{Coord|6.73|73.04|display=inline}}
| [[Maldives]]
| style="text-align: right;" | 51
| style="text-align: right;" | 3,850
| 
|-
! scope="row" | [[Chesterfield Islands]]
| {{Coord|-19.35|158.66|display=inline}}
| [[New Caledonia]]
| style="text-align: right;" | <10
| style="text-align: right;" | 3,500
| 
|-
! scope="row" | [[Huvadhu Atoll]]
| {{Coord|0.50|73.30|display=inline}}
| [[Maldives]]
| style="text-align: right;" | 38.5
| style="text-align: right;" | 3,152
| 
|-
! scope="row" | [[Chuuk Lagoon]]
| {{Coord|7.42|151.78|display=inline}}
| [[Chuuk State|Chuuk]], Micronesia
| style="text-align: right;" | 
| style="text-align: right;" | 3,152
| 
|-
! scope="row" | [[Sabalana Islands]]
| {{Coord|-6.75|118.83|display=inline}}
| [[Indonesia]]
| style="text-align: right;" | 
| style="text-align: right;" | 2,694
|
|-
! scope="row" | [[Lihou Reef National Nature Reserve|Lihou Reef]]
| {{Coord|-17.42|151.67|display=inline}}
| [[Coral Sea]]
| style="text-align: right;" | 1
| style="text-align: right;" | 2,529
| 
|-
! scope="row" | [[Bassas de Pedro]]
| {{Coord|13.08|72.42|display=inline}}
| [[Lakshadweep]], [[India]]
| style="text-align: right;" |
| style="text-align: right;" | 2,474
| Submerged, at shallowest 16.4 m
|-
! scope="row" | Ardasier Bank
| {{Coord|7.71|114.25|display=inline}}
| [[Spratly Islands]]
| style="text-align: right;" |
| style="text-align: right;" | 2,347
| 
|-
! scope="row" | [[Kwajalein Atoll]]
| {{Coord|9.19|167.47|display=inline}}
| [[Marshall Islands]]
| style="text-align: right;" | 16.4
| style="text-align: right;" | 2,304
| 
|-
! scope="row" | Diamond Islets Bank
| {{Coord|-17.42|150.96|display=inline}}
| [[Coral Sea]]
| style="text-align: right;" | <1
| style="text-align: right;" | 2,282
| 
|-
! scope="row" | [[Namonuito Atoll]]
| {{Coord|8.67|150.00|display=inline}}
| [[Chuuk State|Chuuk]], Micronesia
| style="text-align: right;" | 4.4
| style="text-align: right;" | 2,267
| 
|-
! scope="row" | [[Ari Atoll]]
| {{Coord|3.86|72.83|display=inline}}
| [[Maldives]]
| style="text-align: right;" | 69
| style="text-align: right;" | 2,252
| 
|-
! scope="row" | [[Maro Reef]]
| {{Coord|25.42|-170.59|display=inline}}
| [[Northwestern Hawaiian Islands]]
| style="text-align: right;" |
| style="text-align: right;" | 1,934
|
|-
! scope="row" | [[Rangiroa]]
| {{Coord|-15.13|-147.65|display=inline}}
| [[Tuamotus]]
| style="text-align: right;" | 79
| style="text-align: right;" | 1,762
| 
|-
! scope="row" | [[Kolhumadulu Atoll]]
| {{Coord|2.37|73.12|display=inline}}
| [[Maldives]]
| style="text-align: right;" | 79
| style="text-align: right;" | 1,617
| 
|-
! scope="row" | [[Kaafu Atoll]]
| {{Coord|4.42|73.50|display=inline}}
| [[Maldives]]
| style="text-align: right;" | 69
| style="text-align: right;" | 1,565
| 
|-
! scope="row" | [[Ontong Java Atoll]]
| {{Coord|-5.27|159.35|display=inline}}
| [[Solomon Islands]]
| style="text-align: right;" | 12
| style="text-align: right;" | 1500
| 
|-
! scope="row" | [[Lifou Island|Lifou]]
| {{Coord|-20.97|167.23|display=inline}}
| [[New Caledonia]]
| style="text-align: right;" | 
| style="text-align: right;" | 1146
| Raised atoll with no lagoon
|-
! scope="row" | [[Rennell Island|Rennell]]
| {{Coord|-11.67|160.17|display=inline}}
| [[Solomon Islands]]
| style="text-align: right;" |
| style="text-align: right;" | 660
| Raised atoll with no lagoon
|-
! scope="row" | [[Kiritimati]]
| {{Coord|1.85|-157.4|display=inline}}
| [[Kiribati]]
| style="text-align: right;" | 312
| style="text-align: right;" | 640
| 
|}

===Gallery===
<gallery widths="200" heights="200">
Penrhyn Aerial EFS 1280.jpg|[[Penrhyn (atoll)|Penrhyn]] atoll
Maldives.visibleearth.nasa.jpg|upright|[[NASA]] satellite image of some of the [[atolls of the Maldives]], which consists of 1,322 islands arranged into 26 atolls
Nukuoro ISS013-E-28610.jpg|[[Nukuoro]] from space. Courtesy [[NASA]]
Los Roques.png|[[Los Roques Archipelago]] in Venezuela, the largest marine national park in Latin America,<ref name="inparques1" /> from space. Courtesy [[NASA]]
Bikini Atoll Nuclear Test Site-115017.jpg|View of the coast of [[Bikini Atoll]] from above
Maamigili Island Raa Atoll.jpg|[[Raa Atoll]] in [[Maldives]]
Guriadhoo-2019-aerial-view-Luka-Peternel.jpg|[[Kaafu Atoll]] in [[Maldives]]
</gallery>