Cloud forest

[[File:Cloud forest mount kinabalu.jpg|thumb|Tree ferns in a cloud forest on Mount Kinabalu, Borneo]] [[File:Ella Gap (Valley), mountains of Sri Lanka.jpg|thumb|Stratus silvagenitus clouds in Uva Province, Sri Lanka]]

A '''cloud forest''', also called a '''water forest''', '''primas forest''', or '''tropical montane cloud forest''', is a generally tropical or subtropical, evergreen, montane, moist forest characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level, formally described in the ''International Cloud Atlas'' (2017) as '''silvagenitus'''.<ref name="Hostettler">{{cite journal |last1=Hostettler |first1=Silvia |title=Tropical Montane Cloud Forests: A Challenge for Conservation |journal=Bois et Forets des Tropiques |date=2002 |volume=274 |issue=4 |pages=19–31 |doi=10.19182/bft2002.274.a20121 |url=https://www.researchgate.net/publication/299537628|doi-access=free }}</ref><ref>{{cite news|last1=Sutherland|first1=Scott|title=Cloud Atlas joins the digital age while adding a dozen new cloud types|url=https://www.theweathernetwork.com/en/news/science/earth-science/international-cloud-atlas-digital-update-adds-11-new-cloud-types|access-date=13 August 2025|work=The Weather Network|agency=Pelmorex Media|date=March 23, 2017}}</ref> Cloud forests often exhibit an abundance of mosses covering the ground and vegetation, in which case they are also referred to as '''mossy forests'''. Mossy forests usually develop on the saddles of mountains, where moisture introduced by settling clouds is more effectively retained.

Cloud forests form when winds carry moisture-laden air against mountain slopes, causing the air to rise and cool through orographic lift until it condenses into persistent low clouds. This mechanism sustains the characteristically high humidity that defines the biome and sets it apart from other montane forest types.<ref>{{Cite web |last=amazonaid |date=2015-09-23 |title=Cloud Forests |url=https://amazonaid.org/cloud-forests/ |access-date=2026-04-30 |website=Amazon Aid |language=en-US}}</ref>

These forests are among the most biodiversity-rich biomes in the world, harboring a disproportionately large number of endemic plant and animal species that depend on the stable, moist microclimate they provide.<ref name=":1">Karger, Dirk Nikolaus; Kessler, Michael; Lehnert, Marcus; Jetz, Walter (2021). "Limited protection and ongoing loss of tropical cloud forest biodiversity and ecosystems worldwide". Nature Ecology & Evolution. 5 (6): 854–862. Bibcode:2021NatEE...5..854K. doi:10.1038/s41559-021-01450-y. PMID 33927369. S2CID 256726846.</ref> They also play a critical role in regional hydrology: fog drip, condensation that forms on foliage and drips to the ground, can supplement annual precipitation substantially, making cloud forests vital freshwater sources for downstream communities and ecosystems.<ref name=":2">{{harvnb|Vogelmann|1973}} and {{harvnb| Bruijnzeel|1990|p={{pn|date=December 2017}}}} quote by {{harvnb|Hamilton|Juvik|Scatena|1995}}</ref><ref name=":3">{{cite journal |last1=García-Santos |first1=G |last2=Marzol |first2=M. V |last3=Aschan |first3=G |year=2004 |title=Water dynamics in a laurel montane cloud forest in the Garajonay National Park (Canary Islands, Spain) |journal=Hydrology and Earth System Sciences |volume=8 |issue=6 |pages=1065–75 |bibcode=2004HESS....8.1065G |doi=10.5194/hess-8-1065-2004 |doi-access=free}}</ref><ref name=":4">{{Cite journal| last1=Köhler| first1=Lars| last2=Tobón| first2=Conrado|last3=Frumau|first3=K. F. Arnoud| last4=Bruijnzeel|first4=L. A. (Sampurno)| date=2007-12-01| title=Biomass and water storage dynamics of epiphytes in old-growth and secondary montane cloud forest stands in Costa Rica|journal=Plant Ecology| language=en| volume=193| issue=2| pages=171–184| doi=10.1007/s11258-006-9256-7| bibcode=2007PlEco.193..171K|s2cid=1032485|issn=1573-5052}}</ref>

Despite their ecological importance, cloud forests are under threat from deforestation, agricultural encroachment, and climate change. Approximately 2.4% of global cloud forest cover was lost between 2001 and 2018, with losses in some regions exceeding 8%.<ref name=":1" /> Because cloud formation is tightly linked to local temperature and atmospheric conditions, rising global temperatures are projected to push optimal cloud forest climates to higher elevations, effectively shrinking available habitat over the coming decades.<ref name=":5">Foster, Pru (2001). "The potential negative impacts of global climate change on tropical montane cloud forests." Earth-Science Reviews. 55 (1-2): 73-106. </ref><ref name=":6">Bubb, Philip; May, Ian; Miles, Lera; Sayer, Jeff (2004). Cloud Forest Agenda. UNEP World Conservation Monitoring Centre. </ref>

== Climate == [[File:Costa rica santa elena skywalk.jpg|thumb|One of the hanging bridges of the Sky walk at the Monteverde Cloud Forest Reserve in Monteverde, Costa Rica disappearing into the clouds]] Cloud forest distribution is governed by the mixing of latitude, proximity to the ocean, topography, and elevation. Most tropical cloud forests occur between latitudes 25°N and 25°S and at elevations ranging from approximately 500 m to 4,000 m above sea level.<ref name=":7">García-Santos, G; Marzol, M. V; Aschan, G (2004). "Water dynamics in a laurel montane cloud forest in the Garajonay National Park (Canary Islands, Spain)". Hydrology and Earth System Sciences. 8 (6): 1065–75. Bibcode:2004HESS....8.1065G. doi:10.5194/hess-8-1065-2004.</ref> <ref name=":8">García-Santos, G. (2007). An ecohydrological and soils study in a montane cloud forest in the National Park of Garajonay, La Gomera (Canary Islands, Spain) (PhD Thesis). By-Print. hdl:1871/12697.</ref> Within this broad range, suitable conditions are typically restricted to a relatively narrow altitudinal band where atmospheric temperature and humidity permit persistent cloud formation at vegetation level.

The defining climatic mechanism is orographic lift: prevailing winds carry moisture-laden air from the ocean toward mountain ranges, and as the air is forced upward it cools at the dry adiabatic lapse rate until it reaches the dew point, at which point water vapor condenses into cloud. The elevation at which this condensation occurs, the cloud base, is where cloud forests characteristically develop.<ref>Rastogi, Bharat (2016-01-15). "Spatial and Temporal Patterns of Cloud Cover and Fog Inundation in Coastal California: Ecological Implications" (PDF). ''journals.ametsoc.org''. Retrieved 2026-04-29</ref> Once cloud envelops the canopy, direct sunlight is reduced, lowering evapotranspiration and creating the persistently humid conditions in which cloud forest vegetation thrives.<ref name=":7" /><ref name=":8" />

Within cloud forests, a significant proportion of the moisture available to plants arrives not as rainfall but as fog drip: water droplets from the cloud condense on the needles and leaves of trees, coalesce into larger drops, and fall to the ground below.[12] In seasonally dry climates, this fog drip can effectively double the amount of moisture reaching the forest floor compared with rainfall alone, and in wetter climates it augments wet-season precipitation by roughly 10%.<ref name=":2" /><ref name=":3" /><ref name=":4" />

Annual rainfall in cloud forest zones ranges from approximately 500 to 10,000 mm per year, and mean annual temperatures typically fall between 8 and 20 °C (46.4–68 °F).<ref name=":7" /><ref name=":8" /> The relatively cool temperatures suppress rates of decomposition and evapotranspiration, contributing to the waterlogged, peat-rich soils that are characteristic of the biome.

Regional and local terminology for cloud forests varies considerably. Some countries prefer terms such as Afromontane forest, upper montane rain forest, montane laurel forest, or locally specific names such as the Bolivian '''yungas''' and the '''laurisilva''' of the Atlantic Islands.<ref>García-Santos, G; Bruijnzeel, L.A; Dolman, A.J (2009). "Modelling canopy conductance under wet and dry conditions in a subtropical cloud forest". Agricultural and Forest Meteorology. 149 (10): 1565–72. Bibcode:2009AgFM..149.1565G. doi:10.1016/j.agrformet.2009.03.008.</ref><ref name=":3" /> In cooler parts of the tropics where similar meteorological conditions prevail, subtropical and temperate forests are sometimes also classified as cloud forests, though this usage is not universally accepted. <ref>"Cloud forest | Definition, Description, Ecology, Plants, Distribution, & Facts | Britannica". ''Encyclopedia Britannica''. Archived from the original on 2025-09-20. Retrieved 2026-02-16.</ref>

== Characteristics == [[File:Forest Enchantment.jpg|thumb|Bryophyte-covered mossy forest at Mount Dulang-dulang, Philippines]] [[File:Papillaria Cloudforest-Mt Budawang.jpg|thumb|Hanging moss in a cool temperate rainforest at Budawang National Park, Australia]] Compared with lower-altitude tropical moist forests, cloud forests are characterised by reduced tree stature combined with increased stem density and, generally, lower woody plant diversity.<ref name=":7" /><ref name=":8" /> Trees tend to be shorter and more heavily stemmed than their lowland counterparts, with gnarled trunks, dense compact crowns, and leaves that become progressively smaller, thicker, and harder with increasing altitude.<ref>Bruijnzeel, L. A; Proctor, J (1995). "Hydrology and Biogeochemistry of Tropical Montane Cloud Forests: What Do We Really Know?". In Hamilton, Lawrence S.; Juvik, James O.; Scatena, F. N. (eds.). ''Tropical Montane Cloud Forests''. Ecological Studies. Vol. 110. pp. 38–78. doi:10.1007/978-1-4612-2500-3_3. {{ISBN|978-1-4612-7564-0}}.</ref>

The persistently high moisture promotes exceptional development of epiphytes, plants that grow on other plants without making them parasites, particularly bryophytes (mosses and liverworts), lichens, ferns (including filmy ferns), bromeliads, and orchids.<ref name=":9">Häger, Achim (2006). ''Einfluss von Klima und Topographie auf Struktur, Zusammensetzung und Dynamik eines tropischen Wolkenwaldes in Monteverde, Costa Rica'' [''Influence of climate and topography on the structure, composition and dynamics of a tropical cloud forest in Monteverde, Costa Rica''] (Dissertation) (in German). doi:10.53846/goediss-2265. hdl:11858/00-1735-0000-0006-B0EE-1. S2CID 247019823.</ref><ref name=":10">Hamilton, Lawrence S; Juvik, James O; Scatena, F. N (1995). "The Puerto Rico Tropical Cloud Forest Symposium: Introduction and Workshop Synthesis". In Hamilton, Lawrence S.; Juvik, James O.; Scatena, F. N. (eds.). ''Tropical Montane Cloud Forests''. Ecological Studies. Vol. 110. pp. 1–18. doi:10.1007/978-1-4612-2500-3_1. {{ISBN|978-1-4612-7564-0}}.</ref> Epiphyte biomass can be very high; in some cloud forests, the weight of mosses and other epiphytes on a single tree exceeds the weight of the tree's own foliage.<ref>Diaz, Ivan A; Sieving, Kathryn E; Pena-Faxon, ME; Larrain, Juan (2010-03). "Epiphyte diversity and biomass loads of canopy emergent trees in Chilean temperate rain forests: A neglected functional component". ''ResearchGate''.</ref> The number of endemic plant species can also be very high.<ref name=":9" />

Cloud forests are frequently peatlands. The combination of high soil moisture, reduced solar radiation, and low rates of decomposition and mineralisation creates strongly acidic soils, with humus and peat often forming the upper soil layer.<ref name=":10" /><ref>van Steenis, Cornelis Gijsbert Gerrit Jan (1972). ''The Mountain Flora of Java''. Brill. OCLC 741884105.</ref><ref>Grubb, PJ; Tanner, EVJ (July 1976). "The montane forests and soils of Jamaica: a reassessment". ''Journal of the Arnold Arboretum''. '''57''' (3): 313–68. doi:10.5962/p.185865. JSTOR 43794514. S2CID 134572910.</ref>

Stadtmüller (1987) distinguishes two general types of tropical montane cloud forests:

Areas with high annual precipitation due to frequent cloud cover combined with heavy and sometimes persistent orographic rainfall. These forests have perceptible canopy strata, a high number of epiphytes, and a thick peat layer with high water-storage capacity.

Drier areas with mainly seasonal rainfall, where cloud stripping, the interception and deposition of cloud moisture by vegetation, accounts for a large proportion of the total moisture available to plants.<ref>Stadtmüller, Thomas (1987). ''Cloud Forests in the Humid Tropics: A Bibliographic Review''. Bib. Orton IICA / CATIE. ISBN {{ISBN|978-92-808-0670-0}}.</ref>

==Distribution of tropical montane cloud forests== thumb|Distribution of tropical montane cloud forests in 2016<ref name=":0" />. Cloud forests are globally rare: they account for only approximately 1% of the world's woodland area.<ref name=":9" /> A total of around 736 cloud forest sites have been identified in 59 countries by the World Conservation Monitoring Centre, of which 327 were legally protected areas as of 2002.<ref name=":11">"Resources Data – UNEP-WCMC". ''unep-wcmc.org''. Archived from the original on 11 April 2011. Retrieved 12 December 2006.</ref> Important areas occur in Central and South America (principally Costa Rica, Venezuela, Honduras, El Salvador, Guatemala, Mexico, Ecuador, and Colombia), East and Central Africa, India, Sri Lanka, Thailand, Vietnam, Indonesia, Malaysia, the Philippines, Hawaii, Papua New Guinea, and the Caribbean.<ref name="Hostettler" /><ref name=":11" />

A 1997 World Conservation Monitoring Centre database recorded 605 tropical montane cloud forest sites in 41 countries. Of these, 280 sites (46%) were in Latin America, with the largest concentrations in Venezuela (64 sites), Mexico (64), Ecuador (35), and Colombia (28). Southeast Asia and Australasia accounted for 228 sites across 14 countries, with major concentrations in Indonesia (66), Malaysia (54), Sri Lanka (33), the Philippines (32), and Papua New Guinea (28). Africa had 97 sites scattered across 21 countries. Of all 605 sites, 264 were in protected areas.<ref>Mark Aldrich, Clare Billington, Mary Edwards and Ruth Laidlaw (1997) "Tropical Montane Cloud Forests: An Urgent Priority for Conservation" WCMC Biodiversity Bulletin No. 2, World Conservation Monitoring Centre.</ref>

== Conservation status == Cloud forests occupied 0.4% of the global land surface in 2001 and harbored ~3,700 species of birds, mammals, reptiles, amphibians, and tree ferns (~15% of the global diversity of those groups), with half of those species entirely restricted to cloud forests.<ref name=":0" /> Worldwide, ~2.4% of cloud forests (in some regions, more than 8%) were lost between 2001 and 2018, especially in readily accessible places. While protected areas have slowed this decline, a large proportion of loss in TCF cover is still occurring despite formal protection.<ref name=":0">{{cite journal |last1=Karger |first1=Dirk Nikolaus |last2=Kessler |first2=Michael |last3=Lehnert |first3=Marcus |last4=Jetz |first4=Walter |date=2021 |title=Limited protection and ongoing loss of tropical cloud forest biodiversity and ecosystems worldwide |url=https://www.nature.com/articles/s41559-021-01450-y |journal=Nature Ecology & Evolution |volume=5 |issue=6 |pages=854–862 |doi=10.1038/s41559-021-01450-y|pmid=33927369 |bibcode=2021NatEE...5..854K |s2cid=256726846 |url-access=subscription }}</ref>

== Temperate cloud forests == Although not universally accepted as true cloud forests, several forests in temperate regions share strong structural and climatic similarities with their tropical counterparts. The classification is further complicated by the occasional use of "temperate" to describe cool-climate cloud forests within tropical countries.

[[File:Forest Los Tilos.jpg|thumb|250px|right|Temperate cloud forest on La Palma, Canary Islands ]]

=== Distribution by country ===

* Argentina – Salta, Jujuy, Catamarca and Tucumán (Southern Andean Yungas)<ref>{{Cite journal |last1=Albanesi |first1=Sebastián Alejandro |last2=Santos |first2=Daniel Andrés Dos |date=2026-04-20 |title=Linking Thermal Availability to Mammal Activity Patterns through Long-Term Camera Trap Monitoring in the Southern Andean Yungas |url=https://doi.org/10.21203/rs.3.rs-9369097/v1 |access-date=2026-04-30 |website=doi.org |doi=10.21203/rs.3.rs-9369097/v1 }}</ref>

* Australia – Lamington National Park, Springbrook National Park, Mount Bartle Frere and Mount Bellenden Ker (Queensland) and Mount Gower (Lord Howe Island)<ref>{{Cite web |title=Lamington National Park |url=https://parks.qld.gov.au/parks/lamington |access-date=2026-04-30 |website=Parks and forests {{!}} Department of the Environment, Tourism, Science and Innovation |language=en-AU}}</ref><ref>{{Cite web |title=Springbrook National Park |url=https://parks.qld.gov.au/parks/springbrook |access-date=2026-04-30 |website=Parks and forests {{!}} Department of the Environment, Tourism, Science and Innovation |language=en-AU}}</ref><ref>{{Cite web |title=Bartle Frere trail, Wooroonooran National Park |url=https://parks.qld.gov.au/parks/bartle-frere |access-date=2026-04-30 |website=Parks and forests {{!}} Department of the Environment, Tourism, Science and Innovation |language=en-AU}}</ref><ref>{{Citation |title=Mount Bellenden Ker |date=2026-04-06 |work=Wikipedia |url=https://en.wikipedia.org/w/index.php?title=Mount_Bellenden_Ker&oldid=1347327927 |access-date=2026-04-29 |language=en}}</ref><ref>{{Cite news |date=2021-03-07 |title='It's like living in a David Attenborough documentary': Island cloud forest thrives |url=https://www.abc.net.au/news/2021-03-08/cloud-forest-of-lord-howe-island-thrives-since-rat-removal/13216880 |access-date=2026-04-30 |work=ABC News |language=en-AU}}</ref> * Brazil – Serra do Mar coastal forests<ref>{{Cite journal |last1=Pompeu |first1=Patrícia Vieira |last2=Fontes |first2=Marco Aurélio Leite |last3=Mulligan |first3=Mark |last4=Bueno |first4=Inácio Thomaz |last5=de Siqueira |first5=Marinez Ferreira |last6=Acerbi Júnior |first6=Fausto Weimar |last7=Kamino |first7=Luciana Hiromi Yoshino |last8=Waterloo |first8=Maarten J. |last9=Bruijnzeel |first9=L. A. |date=2018-06-01 |title=Assessing Atlantic cloud forest extent and protection status in southeastern Brazil |url=https://www.sciencedirect.com/science/article/pii/S1617138117304119 |journal=Journal for Nature Conservation |volume=43 |pages=146–155 |doi=10.1016/j.jnc.2018.04.003 |bibcode=2018JNatC..43..146P |issn=1617-1381}}</ref> * Chile – Bosque de Fray Jorge National Park<ref>{{Cite web |date=2009-07-22 |title=The Strange Forests that Drink—and Eat—Fog |url=https://www.caryinstitute.org/news-insights/media-coverage/strange-forests-drink-and-eat-fog |access-date=2026-04-30 |website=www.caryinstitute.org |language=en}}</ref> * China – Yunnan Plateau, mountains of southern and eastern China<ref>{{Cite web |date=2022-07-29 |title=Yunnan Plateau Subtropical Evergreen Forests |url=https://www.oneearth.org/ecoregions/yunnan-plateau-subtropical-evergreen-forests/ |access-date=2026-04-30 |website=One Earth |language=en}}</ref> * Costa Rica – Monteverde Cloud Forest Reserve. Approximately 10,500 hectares, containing around 2,500 plant species (including the greatest concentration of orchid species of any single site on Earth), 100 species of mammals, 400 species of birds, 120 species of reptiles, and thousands of insect species.<ref>{{Cite web |title=Monteverdes Cloud Forest |url=https://www.monteverdeinfo.com/cloud-forests/ |access-date=2026-04-30 |website=MONTEVERDEINFO.COM |language=en}}</ref> * Ethiopia – Harenna Forest, Bale Mountains National Park and Kafa Biosphere Reserve<ref>{{Cite web |date=2021-02-24 |title=Ethiopia's Forest in the Clouds - NASA Science |url=https://science.nasa.gov/earth/earth-observatory/ethiopias-forest-in-the-clouds-147970/ |access-date=2026-04-30 |language=en-US}}</ref> * Fiji Islands – Tropical montane cloud forests of Taveuni and Gau Island<ref>Keppel, Gunnar; Thomas, Nunia T (2009). "Composition and structure of the cloud forest on Mt. Delaco, Gau, Fiji" (PDF). ''CSIRO''.</ref> * Iran – Eastern Alborz mountains, Golestan Province<ref>{{Cite web |date=2021-02-16 |title=Cloud forest – Iran Travel Information |url=https://persiaplanet.com/cloud-forest-abr/ |access-date=2026-04-30 |language=en-US}}</ref> * Japan – Parts of Yakushima Island<ref>{{Cite web |last=Centre |first=UNESCO World Heritage |title=Yakushima |url=https://whc.unesco.org/en/list/662/ |access-date=2026-04-30 |website=UNESCO World Heritage Centre |language=en}}</ref> * Portugal – Azores and Madeira (referring primarily to the wetter, higher-altitude laurisilva)<ref>{{Cite journal |last1=González-Montelongo |first1=Cristina |last2=Pérez-Vargas |first2=Israel |date=2024-09-25 |title=On the Conservation of the Canarian Laurel Forest: What Do Lichens Have to Say? |journal=Journal of Fungi (Basel, Switzerland) |volume=10 |issue=10 |pages=668 |doi=10.3390/jof10100668 |doi-access=free |issn=2309-608X |pmc=11508214 |pmid=39452620}}</ref> * Sri Lanka – Upper slopes of the Knuckles Mountain Range, Matale<ref>{{Cite web |last=Lanka |first=Best of |title=Tours in Sri Lanka – Local & Tailor-Made Tours in Sri Lanka & Maldives |url=https://www.bestoflanka.com/ |access-date=2026-04-30 |website=Best of Lanka |language=en}}</ref> * Taiwan – Yuanyang Lake Nature Reserve, Chatianshan Nature Reserve, and Fuxing District, Taoyuan<ref>"Yuanyang Lake Nature Reserve". ''Forestry and Conservancy Agency''. 2026-03-13.</ref>

== Conservation status == [[File:DirkvdM cloudforest.jpg|thumb|At the edge of the Panamanian side of the Parque Internacional la Amistad]]Cloud forests occupied approximately 0.4% of the global land surface in 2001 and harbored around 3,700 species of birds, mammals, reptiles, amphibians, and tree ferns — approximately 15% of global diversity in those groups — with roughly half of those species entirely restricted to cloud forests.<ref name=":1" />

Worldwide, approximately 2.4% of cloud forest cover was lost between 2001 and 2018. In some regions, losses exceeded 8%, and losses were most severe in readily accessible lowland cloud forest zones. Although protected areas have slowed the rate of decline, a significant proportion of loss continues to occur within formally protected areas.<ref name=":1" />

In 1970, the original extent of cloud forests on Earth was estimated at around 50 million hectares.<ref>"WHAT IS A CLOUD FOREST?". ''Ecuador Forest Of Clouds''. Retrieved 2026-04-29.</ref> Population growth, poverty, and uncontrolled land use have contributed to substantial losses since then. The 1990 Global Forest Survey found that 1.1% of tropical mountain and highland forests were being lost annually — a higher rate than in any other tropical forest type.<ref>{{Cite web |title=Forest resources assessment 1990 - Tropical countries |url=https://www.fao.org/4/t0830e/T0830E05.htm#:~:text=At%20end%201990%20lowland%20formations,deforestation%20by%20main%20ecological%20zone |access-date=2026-04-30 |website=www.fao.org}}</ref> In Colombia, one of the countries with the greatest cloud forest area, only 10–20% of the original cover is estimated to remain.[7] Significant areas have been converted to plantations, agriculture, and pasture; important crops in montane forest zones include tea and coffee, and selective logging of unique tree species alters forest structure even where outright clearance has not occurred.<ref name=":10" />

In 2004, approximately one-third of all cloud forests on the planet were under some form of legal protection.<ref>{{harvnb|Kappelle|2004}} quote by {{harvnb|Häger|2006|p={{pn|date=December 2017}}}}</ref> Conservation efforts in some regions have achieved measurable successes: for example, the Monteverde Cloud Forest Reserve in Costa Rica has maintained and expanded its protected area since its establishment, and similar private and community-led reserves across the Andes have helped stabilize cover in targeted localities.<ref>Salazar, Maria Angeles (2017-09-06). "A global view from a mountain town: how conservation became ingrained in Monteverde". ''Conservation news''. Retrieved 2026-04-29</ref>

== Importance == [[File:Nimbosilva de Fray Jorge.jpg|thumb|left|Seaborne moisture is vital to the cloud forest of Fray Jorge that is surrounded by the arid southern reaches of the Atacama Desert.]]

== Watershed function == Cloud forests play a disproportionately important role in the regional hydrological cycle relative to their small global extent. The cloud-stripping mechanism — whereby tree canopies intercept wind-driven cloud moisture — can effectively double rainfall inputs during dry seasons and add approximately 10% to wet-season totals.<ref name=":2" /><ref name=":3" /><ref name=":4" /> Experiments by Costin and Wimbush (1961) demonstrated that the canopies of non-cloud forests intercept and evaporate 20% more precipitation than cloud forests do, meaning that cloud forests deliver a larger net water input to the land surface.<ref>Costin, A. B., and D. J. Wimbush, 1961. “Studies in Catchment Hydrology in the Australian Alps. IV. Interception by Trees of Rain, Cloud and Fog.” (Division of Plant Industry Technical Paper No. 16). Commonwealth Scientific and Industrial Research Organization, Melbourne, Australia.</ref> This function makes cloud forests critical catchment areas for rivers and groundwater systems serving large human populations, particularly in seasonally dry regions such as coastal Peru and northern Chile where cloud forests are virtually the sole source of freshwater.

== Vegetation == Tropical montane cloud forests are not as species-rich as tropical lowland forests in terms of overall woody plant diversity, but they provide habitat for many species found nowhere else on Earth.<ref name=":12">Bruijnzeel, L.A.; Hamilton, L.S. (2000). ''Decision Time For Cloud Forests: Water-Related Issues And Problems Of The Humid Tropics And Other Warm Humid Regions''. Paris, France: UNESCO's IHP Humid Tropics Programme Series No.13.</ref><ref name=":8" />For example, Cerro de la Neblina, a permanently cloud-covered massif in southern Venezuela, supports numerous shrubs, orchids, and insectivorous plants entirely restricted to that single mountain.[26]<ref name=":12" /> The extraordinary richness of epiphytic flora is a particular hallmark: cloud forests harbor a large proportion of the world's orchid, bromeliad, and filmy fern diversity, and bryophyte biomass per unit area frequently exceeds that of any other forest type.<ref>{{cite journal | last1=Lai | first1=G. Y. | last2=Liu | first2=H. C. | last3=Kuo | first3=A. J. | last4=Huang | first4=C. Y. | title=Epiphytic bryophyte biomass estimation on tree trunks and upscaling in tropical montane cloud forests | journal=PeerJ | date=2020 | volume=8 | article-number=e9351 | doi=10.7717/peerj.9351 | doi-access=free | pmid=32566412 | pmc=7295022 }}</ref>

== Fauna == Faunal endemism in cloud forests is exceptionally high. In Peru alone, more than one-third of the country's 270 endemic birds, mammals, and frogs are found in cloud forests.<ref name=":12" /> Globally, cloud forests are particularly important for birds: highly specialized species such as the resplendent quetzal (''Pharomachrus mocinno'') of Central America, numerous hummingbird species, and many tanagers and antpittas are closely tied to cloud forest habitats and are among the region's flagship conservation species. <ref>{{Cite web |title=Birds and Cloud Forests |url=https://cloudforestconservation.org/knowledge/cloud-forest/birds-and-cloud-forests/ |access-date=2026-04-30 |website=Community Cloud Forest Conservation |language=en-US}}</ref>

Among mammals, the spectacled bear (''Tremarctos ornatus''), the only bear native to South America, is one of the best-known cloud forest species and serves as an important seed disperser across Andean cloud forests.<ref name=":10" /> Amphibian diversity is also notable: the cool, moist microclimate supports many frog and salamander species that are highly sensitive to desiccation and temperature change, making them among the most vulnerable groups to projected climate warming.

== Impact of climate change == Because cloud forests are defined by a delicate dependency on specific atmospheric conditions at specific elevations, they are among the ecosystems most sensitive to global climate change. As temperatures rise, the elevation at which cloud condensation occurs shifts upward, pushing the cloud base — and therefore the zone suitable for cloud forest — to higher altitudes and reducing the total land area available.<ref name=":5" /><ref name=":6" />

Projections for Mexico suggest that the geographic extent of environmentally suitable habitat for cloud forests will decline sharply over the next 70 years under most climate scenarios.<ref name=":13">Ponce-Reyes, Rocio; Nicholson, Emily; Baxter, Peter W. J; Fuller, Richard A; Possingham, Hugh (2013). "Extinction risk in cloud forest fragments under climate change and habitat loss". ''Diversity and Distributions''. '''19''' (5–6): 518–29. Bibcode:2013DivDi..19..518P. doi:10.1111/ddi.12064.</ref> A number of climate models indicate that low-altitude cloudiness will be reduced, meaning that some existing cloud forests will experience a drying trend even before temperature-driven habitat loss becomes acute.<ref name=":5" /><ref name=":6" />

As cloud moisture immersion decreases and temperatures rise, the hydrological cycle within these forests will change, and the system will progressively dry out.<ref name=":6" /> This will cause wilting and dieback of epiphytes, which depend on near-constant high humidity for water and nutrient uptake.[29] Frogs, lizards, and other ectotherms are expected to suffer increasing physiological stress from drought and temperature extremes.<ref name=":6" /> Modelling of Mexican cloud forests suggests that these changes could drive the extinction of up to 37 vertebrate species endemic to that region.<ref name=":13" />

Human-induced climate change is also projected to increase the frequency of rapid hurricane intensification, which will periodically cause severe structural damage to tropical montane cloud forests in vulnerable coastal cordilleras.<ref>Li, Yi; Tang, Youmin; Wang, Shuai; Toumi, Ralf; Song, Xiangzhou; Wang, Qiang (2023-08-24). "Recent increases in tropical cyclone rapid intensification events in global offshore regions". ''Nature Communications''. '''14''' (1): 5167. doi:10.1038/s41467-023-40605-2. ISSN 2041-1723. PMC 10449825. PMID 37620321.</ref> Taken together, the consequences of climate change for cloud forests include biodiversity loss, disrupted biogeochemistry, altitude shifts in species ranges, wholesale community reshuffling, and, in some areas, complete disappearance of the ecosystem.<ref name=":5" />

== Footnotes == {{reflist|30em}}

==References== *amazonaid (2015-09-23). "[https://amazonaid.org/cloud-forests/ Cloud forests]". ''Amazon Aid.'' *"Bartle Frere trail, Wooroonooran National Park". ''Parks and forests | Department of the Environment, Tourism, Science and Innovation''. Retrieved 2026-04-29. *"Birds and Cloud Forests". ''Community Cloud Forest Conservation''. Retrieved 2026-04-29. *Britannica Editors. (1998, July 20). ''Cloud forest | Definition, Description, Ecology, Plants, Distribution, & Facts''. Encyclopedia Britannica. <nowiki>http://web.archive.org/web/20250920081136/https://www.britannica.com/science/cloud-forest-ecology</nowiki> *{{cite book |last1=Bruijnzeel |first1=L. A. |year=1990 |title=Hydrology of Moist Tropical Forests and Effects of Conversion: A State of Knowledge Review |url=http://unesdoc.unesco.org/Ulis/cgi-bin/ulis.pl?catno=97405&set=0058484084_0_425&gp=1&lin=1&ll=1 |oclc=222853422 }} * {{cite book |last1=Bruijnzeel |first1=L.A. |last2=Hamilton |first2=L.S. |year=2000 |title=Decision Time For Cloud Forests: Water-Related Issues And Problems Of The Humid Tropics And Other Warm Humid Regions |publisher=UNESCO's IHP Humid Tropics Programme Series No.13 |location=Paris, France |url=http://www.hydrology.nl/ihppublications/141-decision-time-for-cloud-forests.html }} *{{cite book |last1=Bruijnzeel |first1=L. A |last2=Proctor |first2=J |year=1995 |chapter=Hydrology and Biogeochemistry of Tropical Montane Cloud Forests: What Do We Really Know? |pages=38–78 |doi=10.1007/978-1-4612-2500-3_3 |editor1-first=Lawrence S. |editor1-last=Hamilton |editor2-first=James O. |editor2-last=Juvik |editor3-first=F. N. |editor3-last=Scatena |title=Tropical Montane Cloud Forests |volume=110 |series=Ecological Studies |isbn=978-1-4612-7564-0 }} *{{cite book |last1=Bubb |first1=Philip |last2=May |first2=Ian |last3=Miles |first3=Lera |last4=Sayer |first4=Jeff |year=2004 |title=Cloud Forest Agenda |publisher=UNEP World Conservation Monitoring Centre |url=http://old.unep-wcmc.org/biodiversity-series-20_105.html |isbn=92-807-2399-5 |access-date=2017-12-26 |archive-url=https://web.archive.org/web/20171226234858/http://old.unep-wcmc.org/biodiversity-series-20_105.html |archive-date=2017-12-26 |url-status=dead }} *Centre, UNESCO World Heritage. "Yakushima". ''UNESCO World Heritage Centre''. Retrieved 2026-04-29. *{{cite book |last1=Clarke |first1=Charles |year=1997 |title=Nepenthes of Borneo |publisher=Natural History Publications |isbn=978-983-812-015-9 }} *"Cloud forest – Iran Travel Information". 2021-02-16. Retrieved 2026-04-29. *Costin, A. B., and D. J. Wimbush, 1961. “Studies in Catchment Hydrology in the Australian Alps. IV. Interception by Trees of Rain, Cloud and Fog.” (Division of Plant Industry Technical Paper No. 16). Commonwealth Scientific and Industrial Research Organization, Melbourne, Australia. *Diaz, Ivan A; Sieving, Kathryn E; Pena-Faxon, ME; Larrain, Juan (2010-03). "Epiphyte diversity and biomass loads of canopy emergent trees in Chilean temperate rain forests: A neglected functional component". ''ResearchGate''. *"Ethiopia's Forest in the Clouds - NASA Science". 2021-02-24. Retrieved 2026-04-29.' *"Forest resources assessment 1990 - Tropical countries". ''www.fao.org''. Retrieved 2026-04-29. *{{cite journal |last1=Foster |first1=Pru |year=2001 |title=The potential negative impacts of global climate change on tropical montane cloud forests |journal=Earth-Science Reviews |volume=55 |issue=1–2 |pages=73–106 |doi=10.1016/S0012-8252(01)00056-3 |bibcode=2001ESRv...55...73F }} *{{cite journal |last1=García-Santos |first1=G |last2=Marzol |first2=M. V |last3=Aschan |first3=G |year=2004 |title=Water dynamics in a laurel montane cloud forest in the Garajonay National Park (Canary Islands, Spain) |journal=Hydrology and Earth System Sciences |volume=8 |issue=6 |pages=1065–75 |bibcode=2004HESS....8.1065G |doi=10.5194/hess-8-1065-2004 |doi-access=free }} *{{cite thesis |last1=García-Santos |first1=G. |year=2007 |title=An ecohydrological and soils study in a montane cloud forest in the National Park of Garajonay, La Gomera (Canary Islands, Spain) |publisher=By-Print |type=PhD Thesis |hdl=1871/12697 }} *{{cite journal |doi=10.1016/j.agrformet.2009.03.008 |title=Modelling canopy conductance under wet and dry conditions in a subtropical cloud forest |journal=Agricultural and Forest Meteorology |volume=149 |issue=10 |pages=1565–72 |year=2009 |last1=García-Santos |first1=G |last2=Bruijnzeel |first2=L.A |last3=Dolman |first3=A.J |bibcode=2009AgFM..149.1565G }} *González-Montelongo, Cristina; Pérez-Vargas, Israel (2024-09-25). "On the Conservation of the Canarian Laurel Forest: What Do Lichens Have to Say?". ''Journal of Fungi (Basel, Switzerland)''. '''10''' (10): 668. doi:10.3390/jof10100668. ISSN 2309-608X. PMC 11508214. PMID 39452620. *{{cite journal |last1=Grubb |first1=PJ |last2=Tanner |first2=EVJ |date=July 1976 |title=The montane forests and soils of Jamaica: a reassessment |journal=Journal of the Arnold Arboretum |volume=57 |issue=3 |pages=313–68 |doi=10.5962/p.185865 |jstor=43794514 |s2cid=134572910 |doi-access=free }} *{{cite book |last1=Häger |first1=Achim |year=2006 |title=Einfluss von Klima und Topographie auf Struktur, Zusammensetzung und Dynamik eines tropischen Wolkenwaldes in Monteverde, Costa Rica |doi=10.53846/goediss-2265 |trans-title=Influence of climate and topography on the structure, composition and dynamics of a tropical cloud forest in Monteverde, Costa Rica |language=de |type=Dissertation |hdl=11858/00-1735-0000-0006-B0EE-1 |s2cid=247019823 }} *{{cite book |last1=Hamilton |first1=Lawrence S |last2=Juvik |first2=James O |last3=Scatena |first3=F. N |year=1995 |chapter=The Puerto Rico Tropical Cloud Forest Symposium: Introduction and Workshop Synthesis |pages=1–18 |doi=10.1007/978-1-4612-2500-3_1 |editor1-first=Lawrence S. |editor1-last=Hamilton |editor2-first=James O. |editor2-last=Juvik |editor3-first=F. N. |editor3-last=Scatena |title=Tropical Montane Cloud Forests |volume=110 |series=Ecological Studies |isbn=978-1-4612-7564-0 }} *"'It's like living in a David Attenborough documentary': Island cloud forest thrives". ''ABC News''. 2021-03-07. Retrieved 2026-04-29. *{{cite book |last1=Kappelle |first1=M |year=2004 |chapter=Tropical Montane Forests |pages=1782–92 |doi=10.1016/B0-12-145160-7/00175-7 |editor1-first=Jeffery |editor1-last=Burley |title=Encyclopedia of Forest Sciences |isbn=978-0-12-145160-8 }} *Keppel, Gunnar; Thomas, Nunia T (2009). "Composition and structure of the cloud forest on Mt. Delaco, Gau, Fiji" (PDF). ''CSIRO''. *{{cite web |last1=Knutson |first1=T |year=2024 |title=Global Warming and Hurricanes: An overview of current research results |publisher=National Oceanographic and Atmospheric Administration |url=https://www.gfdl.noaa.gov/global-warming-and-hurricanes/ }}' *Lai, Guan-Yu; Liu, Hung-Chi; Kuo, Ariel J.; Huang, Cho-Ying (2020). "Epiphytic bryophyte biomass estimation on tree trunks and upscaling in tropical montane cloud forests". ''PeerJ''. '''8''': e9351. doi:10.7717/peerj.9351. ISSN 2167-8359. PMC 7295022. PMID 32566412. *"Lamington National Park". ''Parks and forests | Department of the Environment, Tourism, Science and Innovation''. Retrieved 2026-04-29. *Lanka, Best of. "Knuckles Forest Reserve, Sri Lanka". ''Best of Lanka''. Retrieved 2026-04-29. *"Monteverdes Cloud Forest". ''MONTEVERDEINFO.COM''. Retrieved 2026-04-29. *Pompeu, Patrícia Vieira; Fontes, Marco Aurélio Leite; Mulligan, Mark; Bueno, Inácio Thomaz; de Siqueira, Marinez Ferreira; Acerbi Júnior, Fausto Weimar; Kamino, Luciana Hiromi Yoshino; Waterloo, Maarten J.; Bruijnzeel, L. A. (2018-06-01). "Assessing Atlantic cloud forest extent and protection status in southeastern Brazil". ''Journal for Nature Conservation''. '''43''': 146–155. doi:10.1016/j.jnc.2018.04.003. ISSN 1617-1381. *{{cite journal |last1=Ponce-Reyes |first1=Rocío |last2=Reynoso-Rosales |first2=Víctor-Hugo |last3=Watson |first3=James E. M |last4=Vanderwal |first4=Jeremy |last5=Fuller |first5=Richard A |last6=Pressey |first6=Robert L |last7=Possingham |first7=Hugh P |year=2012 |title=Vulnerability of cloud forest reserves in Mexico to climate change |journal=Nature Climate Change |volume=2 |issue=6 |pages=448–52 |doi=10.1038/nclimate1453 |bibcode=2012NatCC...2..448P |url=https://espace.library.uq.edu.au/view/UQ:276739/UQ276739_OA.pdf }} *{{cite journal |last1=Ponce-Reyes |first1=Rocio |last2=Nicholson |first2=Emily |last3=Baxter |first3=Peter W. J |last4=Fuller |first4=Richard A |last5=Possingham |first5=Hugh |year=2013 |title=Extinction risk in cloud forest fragments under climate change and habitat loss |journal=Diversity and Distributions |volume=19 |issue=5–6 |pages=518–29 |doi=10.1111/ddi.12064 |doi-access=free |bibcode=2013DivDi..19..518P }} *Rastogi, B., A. Park Williams, Fischer, D. T., Iacobellis, S. F., McEachern, K., Carvalho, L. V., Jones, C., Baguskas, S. A., & Still, C. J. (2016). Spatial and Temporal Patterns of Cloud Cover and Fog Inundation in Coastal California: Ecological Implications. ''Earth Interactions'', ''20''(15), 1–19. <nowiki>https://doi.org/10.1175/ei-d-15-0033.1</nowiki> *Salazar, Maria Angeles (2017-09-06). "A global view from a mountain town: how conservation became ingrained in Monteverde". ''Conservation news''. Retrieved 2026-04-29. *"Springbrook National Park". ''Parks and forests | Department of the Environment, Tourism, Science and Innovation''. Retrieved 2026-04-29. *"The Strange Forests that Drink—and Eat—Fog". ''www.caryinstitute.org''. 2009-07-22. Retrieved 2026-04-29. *{{cite book |first1=Cornelis Gijsbert Gerrit Jan |last1=van Steenis |author-link1=Cornelis Gijsbert Gerrit Jan van Steenis |year=1972 |title=The Mountain Flora of Java |publisher=Brill |oclc=741884105 }} *{{cite journal |last1=Vogelmann |first1=H. W |year=1973 |title=Fog Precipitation in the Cloud Forests of Eastern Mexico |journal=BioScience |volume=23 |issue=2 |pages=96–100 |doi=10.2307/1296569 |jstor=1296569 |bibcode=1973BiSci..23...96V }} *"WHAT IS A CLOUD FOREST?". ''Ecuador Forest Of Clouds''. Retrieved 2026-04-29. *Yuanyang Lake Nature Reserve". ''Forestry and Conservancy Agency''. 2026-03-13.

== External links == {{Commons category|Cloud forests}} * [http://www.unep-wcmc.org/forest/cloudforest/english/homepage.htm Tropical Montane Cloud Forest Initiative] {{Webarchive|url=https://web.archive.org/web/20080405190824/http://www.unep-wcmc.org/forest/cloudforest/english/homepage.htm |date=5 April 2008 }} * [https://web.archive.org/web/20141219044133/http://www.monteverdetours.com/monteverde-cloud-forest.html Monteverde Cloud Forest Ecology] * Roach, John (August 13, 2001). [https://web.archive.org/web/20010822080328/http://news.nationalgeographic.com/news/2001/08/0813_cloudforest.html "Cloud Forests Fading in the Mist, Their Treasures Little Known"]. National Geographic News * {{usurped|1=[https://web.archive.org/web/20211207052320/https://cloudforestsunited.org/ Cloud Forests United]}} * [https://web.archive.org/web/20071012114114/http://www.ambiotek.com/cloudforests/ Tropical hydrology and cloud forests project] * [https://web.archive.org/web/20071118105731/http://www.ambiotek.com/fiesta/ Hydrology of tropical cloud forests project] * [https://www.youtube.com/watch?v=tLZmFDqIEOk Cloud Forest Video – Rara Avis CR] * [http://www.hydrology.nl/ihppublications/290-tropical-montane-cloud-forests-new-benchmark-book-by-bruijnzeel-scatena-and-hamilton.html Tropical Montane Cloud Forests – Science for Conservation and Management (L.A. Bruijnzeel, F.N. Scatena and L.S. Hamilton, 2011)] * [http://www.andesconservation.org/ Andes Biodiversity and Ecosystem Research Group] *{{cite book |first1=A.B. |last1=Costin |first2=D.J. |last2=Wimbush |year=1961 |title=Studies in catchment hydrology in the Australian Alps. IV, Interception by trees of rain, cloud, and fog |oclc=822214607 }} *{{cite book |first1=Thomas |last1=Stadtmüller |year=1987 |title=Cloud Forests in the Humid Tropics: A Bibliographic Review |publisher=Bib. Orton IICA / CATIE |isbn=978-92-808-0670-0 }}

Category:Habitats Category:Montane forests Category:Temperate rainforests Category:Subtropical rainforests Category:Tropical and subtropical moist broadleaf forests Category:Tropical and subtropical coniferous forests Category:Temperate broadleaf and mixed forests