Editing Geography of Indonesia

{{Short description|none}} <!-- "none" is preferred when the title is sufficiently descriptive; see [[WP:SDNONE]] -->
{{EngvarB|date=September 2014}}
{{Use dmy dates|date=May 2023}}
{{Country geography
| name = Indonesia
| map = Indonesia relief location map.jpg
| map size = 250
| continent = [[Asia]]
| region = [[Southeast Asia]]
| coordinates = {{Coord|5.000|S|120.000|E}}
| area ranking = 14th
| km area = 1,904,569<ref name="CIA">[https://web.archive.org/web/20260118180205/https://www.cia.gov/the-world-factbook/countries/indonesia/ CIA World Factbook]</ref>
| percent land = 23.62
| percent water = 76.38
| km coastline = 54720
| borders = [[Malaysia]]: {{convert|2019|km|mi|0|abbr=on}}<br />[[Papua New Guinea]]: {{convert|824|km|mi|0|abbr=on}}<br />[[East Timor]]: {{convert|253|km|mi|0|abbr=on}}
| highest point = [[Puncak Jaya]] (Carstensz Pyramid)<br />{{convert|4884|m|ft|0|abbr=on}}
| lowest point = Sea level<br />{{convert|0|m|ft|0|abbr=on}}
| longest river = [[Kapuas River]]<br />{{convert|1143|km|mi|0|abbr=on}}
| largest lake = [[Lake Toba]]<br />{{convert|1130|km2|sqmi|0|abbr=on}}
| climate = Mostly [[Tropical rainforest climate|tropical rainforest]] (''Af''), Southeastern part is predominantly [[Tropical savanna climate|tropical savanna]] (''Aw''), while some parts of [[Java]] and [[Sulawesi]] are [[Tropical monsoon climate|tropical monsoon]] (''Am'')
| terrain = Plain in most part of [[Kalimantan]], southern [[New Guinea]], eastern [[Sumatra]] and northern Java; Rugged, volcanic topography in Sulawesi, western Sumatra, southern Java, [[Lesser Sunda Islands]] and [[Maluku Islands]]; Rugged mountains in central, northwestern New Guinea and northern Kalimantan
| natural resources = Arable land, coal, petroleum, natural gas, timber, copper, lead, phosphates, uranium, bauxite, gold, iron, mercury, nickel, silver
| natural hazards = Tsunamis; volcanoes; earthquake activity except in central part; tropical cyclones along the [[Indian Ocean|Indian]] coasts; mud slides in Java; flooding
| environmental issues = Severe [[deforestation]], air pollution resulting in acid rain, river pollution
| exclusive economic zone = {{convert|6159032|km2|mi2|abbr=on}}
}}
[[Indonesia]] is an [[Island country|archipelagic country]] located in [[Southeast Asia]], lying between the [[Indian Ocean]] and the [[Pacific Ocean]]. It is located in a strategic location astride or along major sea lanes connecting [[East Asia]], [[South Asia]] and [[Oceania]]. Indonesia is the largest [[archipelago]] in the world.<ref name="world-atlas"/> Indonesia's various regional cultures have been shaped—although not specifically determined—by centuries of complex interactions with its physical environment.

==Overview==
{{main|Indonesian Archipelago|List of islands of Indonesia}}
Indonesia is an archipelagic country extending about {{convert|5120|km|0}} from east to west and {{convert|1760|km|0}} from north to south.<ref>{{Cite book |last1=Frederick|first1=William H. |last2=Worden |first2=Robert L. |title=Indonesia: A Country Study |series=Area Handbook Series |volume=550 |date=1993 |page=98 |url=https://books.google.com/books?id=6dgmXWMgWcwC&pg=PA98 |publisher=Federal Research Division, Library of Congress |location=Washington, D.C. |language=en|isbn=9780844407906 }}</ref> It is considered to be the largest archipelagic country in the world. According to a geospatial survey conducted between 2007 and 2010 by [[Badan Informasi Geospasial|National Coordinating Agency for Survey and Mapping]] (Bakosurtanal), Indonesia has 17,500 islands,<ref name="NG-Indonesia-Island">{{cite news| title = Hanya ada 13.466 Pulau di Indonesia| date = 8 February 2012 | work = National Geographic Indonesia |url=https://nationalgeographic.grid.id/read/13281675/hanya-ada-13466-pulau-di-indonesia | language=id}}</ref> while an earlier survey conducted in 2002 by [[National Institute of Aeronautics and Space]] (LAPAN) stated Indonesia has 18,307 islands. According to the CIA World Factbook, there are 17,508 islands.<ref name="CIA">[https://web.archive.org/web/20260118180205/https://www.cia.gov/the-world-factbook/countries/indonesia/ CIA World Factbook]</ref> The discrepancy between the surveys is likely caused by the earlier different survey method including [[tide|tidal]] islands, sandy [[cay]]s and rocky [[reef]]s that surface during low tide and submerge during high tide. There are 8,844 named islands according to estimates made by the [[Politics of Indonesia|government of Indonesia]], with 922 of those being permanent. Indonesia comprises five main islands: [[Sumatra]], [[Java (island)|Java]], [[Borneo]] (known as ''[[Kalimantan]]'' in Indonesia), [[Sulawesi]], and [[New Guinea]]; two major island groups ([[Nusa Tenggara]] and the [[Maluku Islands]]) and sixty smaller island groups. Four of the islands are shared with other countries: Borneo is shared with [[Malaysia]] and [[Brunei]]; [[Sebatik]], located off the northeastern coast of Kalimantan, is shared with Malaysia; [[Timor]] is shared with [[East Timor]]; and [[New Guinea]] is shared with [[Papua New Guinea]].

Indonesia has total land area of {{convert|1904569|km2|0}}, including {{convert|93000|km2|0}} of inland seas ([[strait]]s, [[bay]]s, and other bodies of water). This makes it the largest [[List of island countries|island country]] in the world.<ref name="world-atlas">{{cite web|url=https://www.worldatlas.com/articles/which-are-the-island-countries-of-the-world.html |title=Island Countries of the World |publisher=WorldAtlas.com |access-date=2019-08-10 |archive-url=https://web.archive.org/web/20171207094959/http://www.worldatlas.com/articles/which-are-the-island-countries-of-the-world.html | archive-date=2017-12-07}}</ref> The additional surrounding sea areas bring Indonesia's generally recognised territory (land and sea) to about 5 million km<sup>2</sup>. The government claims an [[Exclusive economic zone of Indonesia|exclusive economic zone]] of {{convert|6159032|km2|mi2|abbr=on}}. This brings the total area to about 7.9 million km<sup>2</sup>.<ref>{{Cite book|url=https://books.google.com/books?id=E5NafsG5RiEC&q=Indonesia+land+sea+total+area&pg=PA99|title=Prevention and Compensation of Marine Pollution Damage: Recent Developments in Europe, China and the US|last=Faure|first=Michael G.|date=2006|publisher=Kluwer Law International|isbn=9789041123381|language=en}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=6dgmXWMgWcwC&q=Indonesia+total+sea+area&pg=PR32|title=Indonesia: A Country Study|last1=Frederick|first1=William H.|last2=Worden|first2=Robert L.|date=2011|publisher=Government Printing Office|isbn=9780844407906|language=en}}</ref>

During the [[Pleistocene]], the [[Greater Sunda Islands]] were connected to the Asian mainland while New Guinea was connected to Australia.<ref>{{Cite book|url=https://books.google.com/books?id=VWnxpAxp6TMC&q=Sundaland+Pleistocene&pg=PA70|title=Encyclopedia of Coastal Science|last=Schwartz|first=Maurice|date=2006-11-08|publisher=Springer Science & Business Media|isbn=9781402038808|language=en}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=u-k1CwAAQBAJ&q=Sundaland+Pleistocene&pg=PA237|title=Geology and Archaeology: Submerged Landscapes of the Continental Shelf|last1=Harff|first1=J.|last2=Bailey|first2=G.|last3=Lüth|first3=F.|date=2016-01-05|publisher=Geological Society of London|isbn=9781862396913|language=en}}</ref> [[Karimata Strait]], [[Java Sea]] and [[Arafura Sea]] were formed as the [[sea level rise|sea level rose]] at the end of the Pleistocene.

==Geology==
{{main|Geology of Indonesia}}
[[File:Plate setting Sunda megathrust.png|thumb|left|330x330px|The tectonic plates & movements under Indonesia]]

The main islands of Sumatra, Java, [[Madura]], and Kalimantan lie on the [[Sunda plate]] and geographers have conventionally grouped them, (along with Sulawesi), as the [[Greater Sunda Islands]]. At Indonesia's eastern extremity is western New Guinea, which lies on the [[Australian plate]]. Sea depths in the Sunda and Sahul shelves average {{convert|300|m|0}} or less. Between these two shelves lie Sulawesi, Nusa Tenggara (also known as the [[Lesser Sunda Islands]]), and the [[Maluku Islands]] (or the Moluccas), which form a second island group with deep, surrounding seas down to {{convert|4500|m|0}} in depth. The term "Outer Islands" is used inconsistently by various writers, but it is usually taken to mean those islands other than Java and Madura.

Sulawesi is an island that lies on three separate plates, the [[Banda Sea plate]], [[Molucca Sea plate]], and Sunda plate. Seismic and volcanic activities are high on its northeastern part, evidenced by the formation of volcanoes in [[North Sulawesi]] and island arcs such as the [[Sangihe Islands|Sangihe]] and [[Talaud Islands]], southwest of the [[Philippine Trench]].<ref>{{Cite book|url=https://books.google.com/books?id=eilFDwAAQBAJ&q=Mindanao+North+Sulawesi+Arc&pg=PT190|title=Mountains: The origins of the Earth's mountain systems|last=Park|first=Graham|date=2018-01-03|publisher=Dunedin Academic Press|isbn=9781780465791|language=en}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=S68JAQAAIAAJ&q=North+Sulawesi+tectonics|title=The Geology and Tectonics of Eastern Indonesia: Proceedings of the Ccop-Ioc Seatar Working Group Meeting, Bandung, Indonesia, 9–14 July 1979|last=Wiryosujono|first=S.|date=1981|publisher=Pergamon Press|isbn=9780080287324|language=en}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=FyQUAQAAIAAJ&q=Sangihe+Talaud+Philippine+Trench|title=Tectonic Evolution of Southeast Asia|last1=Hall|first1=Robert|last2=Blundell|first2=Derek John|date=1996|publisher=Geological Society|isbn=9781897799529|language=en}}</ref>

Nusa Tenggara consists of two strings of islands stretching eastward from Bali toward southern Maluku. The inner arc of Nusa Tenggara is a continuation of the [[Alpide belt]] chain of mountains and volcanoes extending from Sumatra through Java, Bali, and Flores, and trailing off in the volcanic [[Banda Islands]], which along with the [[Kai Islands]] and the [[Tanimbar Islands]] and other small islands in the [[Banda Sea]] are typical examples of the [[Wallacea]] mixture of Asian and Australasian plant and animal life.<ref>{{WWF ecoregion|id=aa0102|name=Banda Sea Islands moist deciduous forests}}. Worldwildlife.org. Retrieved on 29 September 2010.</ref> The outer arc of Nusa Tenggara is a geological extension of the chain of islands west of Sumatra that includes Nias, Mentawai, and Enggano. This chain resurfaces in Nusa Tenggara in the ruggedly mountainous islands of Sumba and Timor.
[[File:Erupsi Gunung Sinabung 9 Juni 2019 oleh Muh Ma'rufin Sudibyo.jpg|thumb|upright|2019 eruption of [[Mount Sinabung|Sinabung]] in [[North Sumatra]]. Sinabung is one of the most active volcanoes in Indonesia.]]
The Maluku Islands (or Moluccas) are geologically among the most complex of the Indonesian islands, consisted of four different tectonic plates. They are located in the northeast sector of the archipelago, bounded by the Philippine Sea to the north, Papua to the east, and Nusa Tenggara to the southwest. The largest of these islands include [[Halmahera]], [[Seram]] and [[Buru]], all of which rise steeply out of very deep seas and have unique Wallacea vegetation.<ref>{{WWF ecoregion|id=aa0104|name=Terrestrial Ecoregions - Buru rain forests (AA0104)}}. Worldwildlife.org. Retrieved on 29 September 2010.</ref> This abrupt relief pattern from sea to high mountains means that there are very few level coastal plains. To the south lies the [[Banda Sea]]. The convergence between the Banda Sea plate and Australian plate created a chain of volcanic islands called the [[Banda Arc]].<ref>Carter, D. J., Audley-Charles, M. G. & Barber, A. J. Stratigraphical analysis of island arc-continental margin collision in eastern Indonesia. J. Geol. Soc. Lond. 132, 179-189 (1976).</ref><ref>Hamilton, W. Tectonics of the Indonesian Region Vol. 1078 (US Geol. Soc. Prof. Pap., 1979).</ref> The sea also contains the Weber Deep, one of the deepest point in Indonesia.<ref>{{Cite book|url=https://books.google.com/books?id=62zMI9P4Vv8C&q=%22Weber+Deep%22+Banda+Sea+deepest&pg=PA272|title=Ecosystems of the Deep Oceans|last=Tyler|first=P. A.|date=2003-03-27|publisher=Elsevier|isbn=9780080494654|language=en}}</ref><ref>{{Cite news|url=http://www.thejakartapost.com/life/2016/11/29/biggest-exposed-fault-on-earth-found-in-eastern-indonesia.html|title=Biggest exposed fault on earth found in eastern Indonesia|date=29 November 2016|work=The Jakarta Post|access-date=2018-02-17|language=en}}</ref>

[[Geomorphology|Geomorphologists]] believe that the island of New Guinea is part of the Australian continent, both lies on [[Sahul Shelf]] and once joined via a land bridge during the [[Last glacial period]].<ref name="aims">{{cite web|url=http://www.aims.gov.au/pages/reflib/bigbank/pages/bb-04.html|title=Big Bank Shoals of the Timor Sea: An environmental resource atlas|year=2001|publisher=Australian Institute of Marine Science|archive-url=https://web.archive.org/web/20060908082408/http://www.aims.gov.au/pages/reflib/bigbank/pages/bb-04.html|archive-date=8 September 2006|url-status=dead|access-date=2006-08-28}}</ref><ref name="wirantaprawira">{{cite web|url=http://www.wirantaprawira.net/indon/land.html|title=Republik Indonesia|last=Wirantaprawira|first=Dr Willy|year=2003|publisher=Dr Willy Wirantaprawira|archive-url=https://web.archive.org/web/20061018140046/http://www.wirantaprawira.net/indon/land.html|archive-date=2006-10-18|url-status=live|access-date=2006-08-28}}</ref> The tectonic movement of the [[Australian plate]] created towering, snowcapped mountain peaks lining the island's central east–west spine and hot, humid alluvial plains along the coasts.<ref name="JohnsonPage12">{{cite book|title=The Geology of Australia|last=Johnson|first=David Peter|publisher=[[Cambridge University Press]]|year=2004|location=Port Melbourne, Victoria|page=12}}</ref> The [[New Guinea Highlands]] range some {{convert|650|km|0}} east to west along the island, forming a mountainous spine between the northern and southern portion of the island. Due to its tectonic movement, New Guinea experienced many earthquakes and tsunamis, especially in its northern and western part.<ref>MG Audley-Charles, 1986, "Timor–Tanimbar Trough: the foreland basin of the evolving Banda orogen", ''Spec. Publs int. Ass. Sediment'', 8:91–102</ref><ref>{{Cite book|url=https://books.google.com/books?id=Ch_1JlLkKE0C&q=new+guinea+north+west+tectonics&pg=PA4|title=Evolution and Dynamics of the Australian plate|last1=Hillis|first1=R. R.|last2=Müller|first2=R. D.|date=2003-01-01|publisher=Geological Society of America|isbn=9780813723723|language=en}}</ref>

===Tectonism and volcanism===
{{main|Volcanoes of Indonesia}}
Most of the larger islands are mountainous, with peaks ranging between {{convert|2000|and|3800|m|0}} meters above sea level in Sumatra, Java, Bali, Lombok, Sulawesi, and Seram.<ref>{{Cite book|url=https://books.google.com/books?id=GwRWAAAAYAAJ&q=Indonesia+landform+mountain+range|title=Focus on Indonesia|date=1976|publisher=Information Division, Embassy of Indonesia|language=en}}</ref> The country's tallest mountains are located in the [[Jayawijaya Mountains]] and the [[Sudirman Range]] in Papua. The highest peak, [[Puncak Jaya]] ({{convert|4884|m|0}}), is located in the Sudirman Mountains. A string of volcanoes stretches from Sumatra to Nusa Tenggara,<ref>{{cite book|title=Indonesia|last=Witton|first=Patrick|publisher=Lonely Planet|year=2003|isbn=1-74059-154-2|location=Melbourne|page=38}}</ref> then loops around through to the [[Banda Islands]] of Maluku to northeastern Sulawesi. Of the 400 volcanoes, approximately 150 are active.<ref name="gvp">{{cite web|url=http://www.volcano.si.edu/world/region.cfm?rnum=06&rpage=list|title=Volcanoes of Indonesia|work=[[Global Volcanism Program]]|publisher=[[Smithsonian Institution]]|access-date=25 March 2007}}</ref> Two of the most violent volcanic eruptions in modern times occurred in Indonesia; in 1815, [[Mount Tambora]] in [[Sumbawa]] erupted, killing 92,000, and in 1883, [[Krakatau]] erupted, killing 36,000. While volcanic ashes resulted from eruption has positive effects for the fertility of the surrounding soils, it also makes agricultural conditions unpredictable in some areas.

[[Image:Map indonesia volcanoes.gif|thumb|446x446px|A map of [[List of volcanoes in Indonesia|Indonesia's volcanoes]].]]
Indonesia has relatively high tectonic and volcanic activities. It lies on the convergence between the [[Eurasian plate|Eurasian]], [[Indo-Australian plate|Indo-Australian]], [[Pacific plate|Pacific]], and [[Philippine Sea plate]]. The [[Sunda megathrust]] is a 5,500&nbsp;km long fault located off southern coasts of Sumatra, Java and Lesser Sunda Islands, where the Indo-Australian Plate is thrusting northeastward towards the subducting Sunda Plate. Tectonic movement in this fault is responsible for the creation of the [[Sunda Trench]], and mountain ranges across Sumatra, Java, and the Lesser Sunda Islands.<ref>{{Cite book|url=https://books.google.com/books?id=WOmRkO9fsiwC&q=Sunda+megathrust+trench+mountain&pg=PA2|title=From the Ground Up: Perspectives on Post-Tsunami and Post-Conflict Aceh|last1=Daly|first1=Patrick|last2=Feener|first2=R. Michael|last3=Reid|first3=Anthony J. S.|date=2012|publisher=Institute of Southeast Asian Studies|isbn=9789814345194|language=en}}</ref> Many great earthquakes occurred in the vicinity of the fault, such as the [[2004 Indian Ocean earthquake and tsunami|2004 Indian Ocean earthquake]].<ref>{{Cite book|url=https://books.google.com/books?id=1bY6DwAAQBAJ&q=%22Sunda+megathrust%22&pg=PA69|title=Geohazards in Indonesia: Earth Science for Disaster Risk Reduction|last1=Cummins|first1=P. R.|last2=Meilano|first2=I.|date=2017-10-25|publisher=Geological Society of London|isbn=9781862399662|language=en}}</ref> [[Mount Merapi]], located in the Java portion of the megathrust, is the most active [[volcano]] in Indonesia and is designated as one of world's [[Decade Volcanoes]] due to the hazard it poses to the surrounding populated areas.<ref>{{Cite book|url=https://books.google.com/books?id=1j0AaQXWORkC&q=Merapi+decade+volcanoes&pg=PA1418|title=Geodetic And Geophysical Effects Associated With Seismic And Volcanic Hazards|last=Fernandez|first=José|date=2004-06-25|publisher=Springer Science & Business Media|isbn=9783764370442|language=en}}</ref> The 2004 Indian Ocean earthquake and tsunami devastated the Indonesian provinces of Aceh and North Sumatra, resulting in approximately 225,000 deaths and leaving over 425,000 people homeless. The disaster caused significant damage to infrastructure, homes, and local industries. The Indonesian government, in partnership with international organizations like the IMF, World Bank, and ADB, coordinated relief and reconstruction efforts. Preliminary assessments estimated the reconstruction cost at $4-5 billion over five years. During a donor meeting in January 2005, nearly $4 billion in aid was pledged for reconstruction, with a focus on transparency and efficient fund management. Despite the severe local impact, the overall effect on Indonesia’s national GDP was limited, as the Aceh region contributed only about 2% of national output. The Paris Club also offered a temporary debt moratorium, which helped fund rebuilding without diverting domestic financial resources.<ref>{{Cite web |title=Preliminary Assessment of the Macroeconomic Impact of The Tsunami Disaster on Affected Countries, and of Associated Financing Needs |url=https://www.imf.org/external/np/oth/2005/020405.htm |access-date=2024-11-16 |website=www.imf.org}}</ref>

The northern part of Sulawesi and Maluku Islands lie on the convergence of Sunda Plate and [[Molucca Sea plate]], making it an active tectonic region with volcanic chains such as the [[Sangihe Islands|Sangihe]] and [[Talaud Islands]].<ref>{{Cite book|url=https://books.google.com/books?id=9YFGGjz1oVsC&q=Sunda+Molucca+Sea+Plate&pg=PA29|title=Dynamics of Crustal Magma Transfer, Storage and Differentiation|last1=Annen|first1=Catherine|last2=Zellmer|first2=Georg F.|date=2008|publisher=Geological Society of London|isbn=9781862392588|language=en}}</ref> Northern Maluku and western New Guinea is located on the convergence of [[Bird's Head plate|Bird's Head]], [[Philippine Sea plate|Philippine Sea]] and [[Caroline plate]]. It is also a seismically active region, with the 7.6 [[Moment magnitude scale|M<sub>w</sub>]] [[2009 Papua earthquakes]] being the most recent great earthquake to date in the region.<ref>{{Cite book|url=https://books.google.com/books?id=FyQUAQAAIAAJ&q=Philippine+Caroline+Bird's+Head+Plate|title=Tectonic Evolution of Southeast Asia|last1=Hall|first1=Robert|last2=Blundell|first2=Derek John|date=1996|publisher=Geological Society|isbn=9781897799529|language=en}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=1bY6DwAAQBAJ&q=2009+Manokwari+earthquake&pg=PA103|title=Geohazards in Indonesia: Earth Science for Disaster Risk Reduction|last1=Cummins|first1=P. R.|last2=Meilano|first2=I.|date=2017-10-25|publisher=Geological Society of London|isbn=9781862399662|language=en}}</ref><ref>{{Cite web|url=https://earthquaketrack.com/quakes/2009-01-03-22-33-40-utc-7-4-23|title=7.4 magnitude earthquake near Manokwari, West Papua, Indonesia : January 03, 2009 22:33|website=earthquaketrack.com|language=en|access-date=2018-02-06}}</ref>

== Ecology ==
{{see also|List of ecoregions in Indonesia|Biodiversity of Borneo|Deforestation in Indonesia}}
Borneo is the third largest island in the world, and the native vegetation was mostly [[Borneo lowland rain forests]], although much of this has been cleared with wildlife retreating to the [[Borneo montane rain forests]] inland. The islands of [[North Maluku]] are the original Spice Islands, a distinct [[rainforest]] [[ecoregion]].<ref>{{WWF ecoregion|id=aa0106|name=Terrestrial Ecoregions - Halmahera rain forests (AA0106)}}. Worldwildlife.org. Retrieved on 29 September 2010.</ref> A number of islands off the coast of New Guinea have their own distinctive biogeographic features, including the limestone islands of [[Schouten Islands|Biak]], in the entrance to the large [[Cenderawasih Bay]] at the northwest end of the island.<ref>{{WWF ecoregion|id=aa0105|name=Terrestrial Ecoregions - Central Range montane rain forests (AA0105)}}. Worldwildlife.org. Retrieved on 29 September 2010.</ref><ref>{{WWF ecoregion|id=aa0103|name=Terrestrial Ecoregions - Biak-Numfoor rain forests (AA0103)}}. Worldwildlife.org. Retrieved on 29 September 2010.</ref>

A recent global remote sensing analysis suggested that there were 14,416&nbsp;km<sup>2</sup> of tidal flats in Indonesia, ranking it 1st in the world in terms of how much tidal flat occurs there.<ref>{{cite journal |last1=Murray |first1=N.J. |last2=Phinn |first2=S.R. |last3=DeWitt |first3=M. |last4=Ferrari |first4=R. |last5=Johnston |first5=R. |last6=Lyons |first6=M.B. |last7=Clinton |first7=N. |last8=Thau |first8=D. |last9=Fuller |first9=R.A. |title=The global distribution and trajectory of tidal flats |journal=Nature |date=2019 |volume=565 |issue=7738 |pages=222–225 |doi=10.1038/s41586-018-0805-8 |pmid=30568300 |s2cid=56481043 |url=https://www.nature.com/articles/s41586-018-0805-8|url-access=subscription }}</ref> Another global analysis also estimated that Indonesia experienced the greatest total tidal wetland change (36% of global net change including [[mangrove]]s, [[Mudflat|tidal flats]], and [[Salt marsh|tidal marshes]]) between 1999 and 2019 with a net loss of {{convert|1,426|km2|mi2|abbr=on}}.<ref name="Murray et al. 2022">{{cite journal |last1=Murray |first1=Nicholas J. |last2=Worthington |first2=Thomas A. |last3=Bunting |first3=Pete |last4=Duce |first4=Stephanie |last5=Hagger |first5=Valerie |last6=Lovelock |first6=Catherine E. |last7=Lucas |first7=Richard |last8=Saunders |first8=Megan I. |last9=Sheaves |first9=Marcus |last10=Spalding |first10=Mark |last11=Waltham |first11=Nathan J. |last12=Lyons |first12=Mitchell B. |title=High-resolution mapping of losses and gains of Earth's tidal wetlands |journal=Science |date=13 May 2022 |volume=376 |issue=6594 |pages=744–749 |doi=10.1126/science.abm9583|pmid=35549414 |bibcode=2022Sci...376..744M |s2cid=248749118 |url=https://www.repository.cam.ac.uk/handle/1810/337253 |doi-access=free |hdl=2160/55fdc0d4-aa3e-433f-8a88-2098b1372ac5 |hdl-access=free }}</ref>

== Time zones ==
{{main|Time in Indonesia}}

Indonesia is divided into three [[time zone]]s:
*'''Western Indonesian Time/WIT''' ([[Indonesian language|Indonesian]]: ''Waktu Indonesia Barat''/'''WIB''') ([[UTC+07:00|UTC+7]])
**WIB is observed in islands of [[Sumatra]], [[Java (island)|Java]], provinces of [[West Kalimantan]] and [[Central Kalimantan]].
*'''Central Indonesian Time/CIT''' (''Waktu Indonesia Tengah''/'''WITA''') ([[UTC+08:00|UTC+8]])
**WITA is observed in islands of [[Sulawesi]], [[Lesser Sunda Islands]], provinces of [[East Kalimantan]], [[South Kalimantan]], and [[North Kalimantan]].
*'''Eastern Indonesian Time/EIT''' (''Waktu Indonesia Timur''/'''WIT''') ([[UTC+09:00|UTC+9]]).
**WIT is observed in provinces of [[Maluku (Indonesian province)|Maluku]], [[North Maluku]], [[Papua (Indonesian province)|Papua]], [[West Papua (province)|West Papua]], [[Southwest Papua]], [[Central Papua]], [[South Papua]], and [[Highland Papua]].

== Climate ==
{{main|Climate of Indonesia}}
{{see also|Climate change in Indonesia}}
[[File:Koppen-Geiger Map IDN present.svg|thumb|374x374px|[[Köppen climate classification|Köppen–Geiger climate classification]] map for Indonesia]]
Lying along the equator, Indonesia's climate tends to be relatively even year-round. Indonesia has two seasons—a wet season and a dry season—with no extremes of summer or winter. For most of Indonesia, the dry season falls between May and October while the wet season between November and April.

Some regions, such as Kalimantan and Sumatra, experience only slight differences in rainfall and temperature between the seasons, whereas others, such as Nusa Tenggara, experience far more pronounced differences with droughts in the dry season, and floods in the wet. Rainfall in Indonesia is plentiful, particularly in west Sumatra, northwest Kalimantan, west Java, and western New Guinea.

Parts of Sulawesi and some islands closer to Australia, such as [[Sumba]] and [[Timor]], are drier; however, these are exceptions. The almost uniformly warm waters that make up 81% of Indonesia's area ensure that temperatures on land remain fairly constant, with the coastal plains averaging {{convert|28|°C|1}}, the inland and mountain areas averaging {{convert|26|°C|1}}, and the higher mountain regions averaging {{convert|23|°C|1}}. The area's relative humidity ranges between 70 and 90%.

Winds are moderate and generally predictable, with [[monsoon]]s usually blowing in from the south and east in June through October and from the northwest in November through March. [[Typhoon]]s and large scale storms pose little hazard to mariners in Indonesia waters; the major danger comes from swift currents in channels, such as the [[Lombok Strait|Lombok]] and [[Sape Strait|Sape]] straits.

Indonesia's climate is almost entirely tropical, dominated by the tropical rainforest climate found in every major island of Indonesia, followed by the tropical monsoon climate that predominantly lies along Java's coastal north, Sulawesi's coastal south and east, and Bali, and finally the tropical savanna climate, found in isolated locations of Central Java, lowland East Java, coastal southern Papua and smaller islands to the east of Lombok.

However, cooler climate types do exist in mountainous regions of Indonesia 1,300–1,500 metres above sea level. The oceanic climate (Köppen ''Cfb'') prevail in highland areas with fairly uniform precipitation year-round, adjacent to rainforest climates, while the subtropical highland climate (Köppen ''Cwb'') exist in highland areas with a more pronounced dry season, adjacent to tropical monsoon and savanna climates.

Above 3000 metres is where cold, subpolar climates dominate and where frost and occasional snow become more commonplace. The subpolar oceanic climate (Köppen ''Cfc''), existing between 3,000 and 3,500 metres, can be found on the mountain slopes of Indonesia's highest peaks, and serves as a transition between oceanic climates and tundra climates. Tundra climates (Köppen ''ET''), are found anywhere above 3500 metres on the highest peaks of Indonesia, including the permanently snow-capped peaks in Papua. In this climate regime, average monthly temperatures are all below 10&nbsp;°C, and monthly precipitation is uniform.

==Environmental issues==
{{main|Environmental issues in Indonesia}}

[[File:Riau palm oil 2007.jpg|thumb|Deforestation in Riau province, Sumatra, to make way for an [[oil palm]] plantation, 2007.]]
Indonesia's high population and rapid industrialisation present serious [[Environmental issues in Indonesia|environmental issues]], which are often given a lower priority due to high poverty levels and weak, under-resourced governance.<ref name="forestprob">{{Cite web |author=Jason R. Miller |title=Deforestation in Indonesia and the Orangutan Population |publisher=TED Case Studies |date=30 January 1997 |url=http://www.american.edu/TED/orang.htm |access-date=14 August 2007 |archive-url=https://web.archive.org/web/20160229155532/http://www1.american.edu/TED/orang.htm |archive-date=2016-02-29 |url-status=dead}}</ref> Issues include [[Deforestation in Indonesia|large-scale deforestation]] (much of it [[illegal logging|illegal]]) and related wildfires causing [[Smog#Southeast Asia|heavy smog]] over parts of western Indonesia, Malaysia and Singapore; over-exploitation of marine resources; and environmental problems associated with rapid [[urbanisation]] and [[economic development]], including [[air pollution]], [[traffic congestion]], garbage management, and reliable water and [[Wastewater|waste water]] services.<ref name="forestprob" />

Deforestation and the destruction of peatlands make Indonesia the world's third largest emitter of greenhouse gases.<ref>{{cite news |last=Higgins |first=Andrew |title=A climate threat, rising from the soil | newspaper=The Washington Post | url= https://www.washingtonpost.com/wp-dyn/content/article/2009/11/18/AR2009111804162.html |access-date=11 December 2009 | date=19 November 2008}}</ref> [[Habitat destruction]] threatens the survival of indigenous and endemic species, including 140 species of [[mammals]] identified by the [[World Conservation Union]] (IUCN) as [[threatened species|threatened]], and 15 identified as critically endangered, including the Sumatran Orangutan.<ref>{{cite web |last=Massicot |first=Paul |title=Animal Info – Indonesia |publisher=Animal Info – Information on Endangered Mammals |url=http://www.animalinfo.org/country/indones.htm |access-date=14 August 2007}}</ref>

In 1978, 14% of Indonesians lived in cities compared to over 30% today, and this increases pressure on the urban environment. Industrial pollution is increasing, particularly in Java, and the increasing affluence of the growing middle class drives a rapid increase in the number of motor vehicles and associated emissions. Garbage and waste water services are being placed under increasing pressure. Reliance on septic systems or effluent disposal in open canals and [[List of rivers of Indonesia|river systems]] remains the norm, and is a major polluter of water resources. Very few Indonesians have access to safe drinking water and must boil water before use.

The geographical resources of the Indonesian archipelago have been exploited in ways that fall into consistent social and historical patterns. One cultural pattern consists of the formerly Indianized, rice-growing peasants in the valleys and plains of Sumatra, Java, and Bali, another cultural complex is composed of the largely Islamic coastal commercial sector, a third, more marginal sector consists of the upland forest farming communities which exist by means of subsistence swidden agriculture. To some degree, these patterns can be linked to the geographical resources themselves, with abundant shoreline, generally calm seas, and steady winds favouring the use of sailing vessels, and fertile valleys and plains—at least in the Greater Sunda Islands—permitting irrigated rice farming. The heavily forested, mountainous interior hinders overland communication by road or river, but fosters slash-and-burn agriculture.

==Statistics==
[[File:East Indonesia Island Chain from ISS.jpg|thumb|upright|Java and eastern Indonesia photographed in 2015 by an astronaut on the [[International Space Station]]. Six active [[volcano]]s are visible. Haze is from wildfires.]]
'''Area:'''
<br>''total land area:'' 1,904,569&nbsp;km<sup>2</sup> (''land:'' 1,811,569&nbsp;km<sup>2 (699450&nbsp;mi<sup>2</sup>)</sup>,
''inland water:'' {{convert|93,000|km2|sqmi|abbr=on}}

'''Area – comparative:'''

* Slightly smaller than [[Nunavut]], [[Canada]]
* Slightly larger than combined area of [[Alaska]] and [[New England]]
* More than 27 times larger than [[Republic of Ireland]]
* ''Territorial area:'' 5,193,250&nbsp;km<sup>2</sup><ref name="territorialarea">{{Cite journal|author=Chris Carl Forward |title=Archipelagic Sea-Lanes in Indonesia – Their legality in International Law |journal=Australian and New Zealand Maritime Law Journal |volume=23 |issue=2 |year=2009 |url=https://maritimejournal.murdoch.edu.au/index.php/maritimejournal/issue/view/9 |access-date=24 February 2011 |url-status=dead |archive-url=https://web.archive.org/web/20110221080117/https://maritimejournal.murdoch.edu.au/index.php/maritimejournal/issue/view/9 |archive-date=21 February 2011}}</ref>
* ''Total area (including exclusive economic zone):'' 8,063,601&nbsp;km<sup>2</sup>

'''Land boundaries:'''
* ''Total:'' {{convert|3096|km|}}
* ''Border countries:'' [[Malaysia]] {{convert|2019|km|}}, [[Papua New Guinea]] {{convert|824|km}}, [[East Timor]] {{convert|253|km}}
* ''Other nearby countries:'' [[Australia]], [[Brunei]], [[Cambodia]], [[India]], [[Laos]], [[Myanmar]], [[Palau]], [[Philippines]], [[Singapore]], [[Sri Lanka]], [[Thailand]], [[Vietnam]]

'''Coastline:''' {{convert|54720|km|mi|abbr=on}}

'''Maritime claims:''' measured from claimed archipelagic baselines
<br>''territorial sea:'' {{convert|12|nmi|mi km|1|abbr=on}}
<br>''[[Exclusive economic zone of Indonesia|exclusive economic zone]]:'' {{convert|6159032|km2|mi2|abbr=on}} with {{convert|200|nmi|mi km|1|abbr=on|lk=on}}

'''Elevation extremes:'''
<br>''lowest point:'' Sea level at 0 m (sea surface level); southern portion of the [[Philippine Trench]], east of [[Miangas]] at {{convert|-9,125|m|ft}}<br>''highest point:'' [[Puncak Jaya]] (also known as ''Carstensz Pyramid'') 4,884 m
[[File:Puncakjaya.jpg|thumb|Puncak Jaya, the highest mountain in Indonesia]]
'''Land use:'''
<br>''arable land:'' 12.97%
<br>''permanent crops:'' 12.14%
<br>''other:'' 74.88% (2013)

'''Irrigated land:''' 67,220&nbsp;km<sup>2</sup> (2005) (25,953&nbsp;mi<sup>2</sup>)

'''Total renewable water resources:''' 2,019&nbsp;km<sup>3</sup> (2011) (484&nbsp;mi<sup>3</sup>)

'''Freshwater withdrawal (domestic/industrial/agricultural):'''
<br>''total:'' 113.3&nbsp;km<sup>3</sup>/yr (11%/19%/71%)
<br>''per capita:'' 517.3 m<sup>3</sup>/yr (2005)

'''Natural resources:''' [[coal]], [[petroleum]], [[natural gas]], [[tin]], [[nickel]], [[timber]], [[bauxite]], [[copper]], fertile [[soil]]s, [[gold]], [[silver]]

== See also ==
* [[List of Indonesian provinces by highest point]]

== References ==
{{Reflist}}

== External links ==
* [https://web.archive.org/web/20170808093420/http://www.indonesianhistory.info/pages/historical-maps.html Digital Atlas of Indonesian History by Robert Cribb] from 17th century and earlier
* {{in lang|en|fr}}[http://www.wdl.org/en/item/460 "Map of a Part of China, the Philippine Islands, the Isles of Sunda, the Moluccas, the Papuans"] features a map of Indonesia from around 1760
* {{country study|country=Indonesia|abbr=id}}
* {{CIA World Factbook}}

{{Indonesia topics}}
{{Geography of Asia}}
{{Asia topic|Climate of}}

[[Category:Geography of Indonesia| ]]