Ring of Fire

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The Pacific Ring of Fire

 

Global earthquakes (1900–2013)
: EQs M7.0+ (depth 0–69km)
: Active volcanoes

 

Global map of subduction zones, with subducted slabs contoured by depth

 

Subduction zone

The Ring of Fire (also known as the Pacific Ring of Fire, the Rim of Fire, the Girdle of Fire or the Circum-Pacific belt) is a region around much of the rim of the Pacific Ocean where many volcanic eruptions and earthquakes occur. The Ring of Fire is a horseshoe-shaped belt about 40,000 km (25,000 mi) long and up to about 500 km (310 mi) wide.

The Ring of Fire includes the Pacific coasts of South America, North America and Kamchatka, and some islands in the western Pacific Ocean. Although there is consensus among geologists about almost all areas which are included in the Ring of Fire, they disagree about the inclusion or exclusion of a few areas, for example, the Antarctic Peninsula and western Indonesia.

The Ring of Fire is a direct result of plate tectonics: specifically the movement, collision and destruction of lithospheric plates under and around the Pacific Ocean. The collisions have created a nearly continuous series of subduction zones, where volcanoes are created and earthquakes occur. Consumption of oceanic lithosphere at these convergent plate boundaries has formed oceanic trenches, volcanic arcs, back-arc basins and volcanic belts.

The Ring of Fire is not a single geological structure. Volcanic eruptions and earthquakes in each part of the Ring of Fire occur independently of eruptions and earthquakes in the other parts of the Ring.

The Ring of Fire contains approximately 850–1,000 volcanoes that have been active during the last 11,700 years (about two-thirds of the world's total). The four largest volcanic eruptions on Earth in the last 11,700 years occurred at volcanoes in the Ring of Fire. More than 350 of the Ring of Fire's volcanoes have been active in historical times.

Beside and among the currently active and dormant volcanoes of the Ring of Fire are belts of older extinct volcanoes, which were formed long ago by subduction in the same way as the currently active and dormant volcanoes; the extinct volcanoes last erupted many thousands or millions of years ago. The Ring of Fire has existed for more than 35 million years but subduction has existed for much longer in some parts of the Ring of Fire.

Most of Earth's active volcanoes with summits above sea level are located in the Ring of Fire. Many of these subaerial volcanoes are stratovolcanoes (e.g. Mount St Helens), which are formed by explosive eruptions of tephra, alternating with effusive eruptions of lava flows. Lavas at the Ring of Fire's stratovolcanoes are mainly andesite and basaltic andesite but dacite, rhyolite, basalt and some other rarer types also occur. Other types of volcano are also found in the Ring of Fire, such as subaerial shield volcanoes (e.g. Plosky Tolbachik), and submarine seamounts (e.g. Monowai).

The world's highest active volcano is Ojos del Salado (6,893 m (22,615 ft)), which is in the Andes Mountains section of the Ring of Fire. It forms part of the border between Argentina and Chile and it last erupted in AD 750. Another Ring of Fire Andean volcano on the Argentina-Chile border is Llullaillaco (6,739 m (22,110 ft)), which is the world's highest historically active volcano, last erupting in 1877.

About 76% of the Earth's seismic energy is released as earthquakes in the Ring of Fire. About 90% of the Earth's earthquakes and about 81% of the world's largest earthquakes occur along the Ring of Fire.

History

From Ancient Greek and Roman times until the late 18th century, volcanoes were associated with fire, based on the ancient belief that volcanoes were caused by fires burning within the Earth. This historical link between volcanoes and fire is preserved in the name of the Ring of Fire, despite the fact that volcanoes do not burn the Earth with fire.

The existence of a belt of volcanic activity around the Pacific Ocean was known in the early 19th century; for example, in 1825 the pioneering volcanologist G.P. Scrope described the chains of volcanoes around the Pacific Ocean's rim in his book "Considerations on Volcanos". Three decades later, a book about the Perry Expedition to Japan commented on the Ring of Fire volcanoes as follows: "They [the Japanese Islands] are in the line of that immense circle of volcanic development which surrounds the shores of the Pacific from Tierra del Fuego around to the Moluccas." (Narrative of the Expedition of an American Squadron to the China Seas and Japan, 1852–54).

Early explicit references to volcanoes forming a "ring of fire" around the Pacific Ocean include Alexander P. Livingstone's book "Complete Story of San Francisco's Terrible Calamity of Earthquake and Fire", published in 1906, in which he describes "... the great ring of fire which circles round the whole surface of the Pacific Ocean.".

In 1912, geologist Patrick Marshall introduced the term "Andesite Line" to mark a boundary between islands in the southwest Pacific, which differ in volcano structure and lava types. The concept was later extended to other parts of the Pacific Ocean. The Andesite Line and the Ring of Fire closely match in terms of location.

The development of the theory of plate tectonics since the early 1960s has provided the current understanding and explanation of the global distribution of volcanoes and earthquakes, including those in the Ring of Fire.

Geographic boundaries

There is consensus among geologists about most of the regions which are included in the Ring of Fire. There are, however, a few regions on which there is no universal agreement. (See: § Distribution of volcanoes). Indonesia lies at the intersection of the Ring of Fire and the Alpide belt (which is the Earth's other very long subduction-related volcanic and earthquake zone, also known as the Mediterranean–Indonesian volcanic belt, running east–west through southern Asia and southern Europe). Some geologists include all of Indonesia in the Ring of Fire; many geologists exclude Indonesia's western islands (which they include in the Alpide belt).

Some geologists include the Antarctic Peninsula and the South Shetland Islands in the Ring of Fire, other geologists exclude these areas. The rest of Antarctica is excluded because the volcanism there is not related to subduction.

The Ring of Fire does not extend through the southern Pacific Ocean between New Zealand and the Antarctic Peninsula or the southern tip of South America because the submarine plate boundaries in this part of the Pacific Ocean (the Pacific-Antarctic Ridge, the East Pacific Rise and the Chile Ridge) are divergent instead of convergent. Although some volcanism occurs in this region, it is not related to subduction.

Some geologists include the Izu Islands, the Bonin Islands, and the Mariana Islands, other geologists exclude them.

Land areas

• Antarctica
  • Antarctic Peninsula
  • South Sandwich Islands
  • Andes
    • Austral Volcanic Zone
    • South Volcanic Zone
    • Central Volcanic Zone
    • North Volcanic Zone
  • Central America Volcanic Arc
    • Trans-Mexican Volcanic Belt
  • North American Cordillera
    • Cascade Volcanic Arc
    • Aleutian Range
      • Aleutian Islands
    • Aleutian Arc
• Kamchatka Peninsula
• Kuril Islands
• Japan
• Ryukyu Islands
• Taiwan
• Philippine Mobile Belt
• Izu-Bonin-Mariana Arc
  • Izu Islands
  • Bonin Islands
  • Mariana Islands
• Sunda Arc
• Lesser Sunda Islands
• Tanimbar and Kai Islands
• Bismarck Archipelago
• New Hebrides
• Bougainville Island
• Solomon Islands
• Fiji
• Tonga Islands
• Kermadec Islands
• Taupo Volcanic Zone

Volcanoes in the central parts of the Pacific Basin, for example the Hawaiian Islands, are very far from subduction zones and they are not part of the Ring of Fire.

Tectonic plate configurations

The Ring of Fire has existed for more than 35 million years. In some parts of the Ring of Fire, subduction has been occurring for much longer.

The current configuration of the Pacific Ring of Fire has been created by the development of the present-day subduction zones, initially (by about 115 million years ago) in South America, North America and Asia. As plate configurations gradually changed, the current subduction zones of Indonesia and New Guinea were created (about 70 million years ago), followed finally by the New Zealand subduction zone (about 35 million years ago).

Past plate configurations

Along the coast of east Asia, during the Late Triassic about 210 million years ago, subduction of the Izanagi Plate (the Paleo-Pacific Plate) was occurring, and this continued in the Jurassic, producing volcanic belts, for example, in what is now eastern China.

The Pacific Plate came into existence in the Early Jurassic about 190 million years ago, far from the margins of the then Paleo-Pacific Ocean. Until the Pacific Plate grew large enough to reach the margins of the ocean basin, other older plates were subducted ahead of it at the ocean basin margins. For example, subduction has been occurring at the coast of South America since the Jurassic Period more than 145 million years ago, and remnants of Jurassic and Cretaceous volcanic arcs are preserved there.

At about 120 to 115 million years ago, the Farallon Plate was subducting under South America, North America and north-east Asia while the Izanagi Plate was subducting under east Asia. By 85 to 70 million years ago, the Izanagi Plate had moved north-eastwards and was subducting under east Asia and North America, while the Farallon Plate was subducting under South America and the Pacific Plate was subducting under east Asia. About 70 to 65 million years ago, the Farallon plate was subducting under South America, the Kula Plate was subducting under North America and north-east Asia, and the Pacific Plate was subducting under east Asia and Papua New Guinea. About 35 million years ago, the Kula and Farallon plates had been subducted and the Pacific Plate was subducting around its rim in a configuration closely resembling the outline of the present-day Ring of Fire.

Present-day plate configuration

Present-day principal tectonic plates of the Earth

The eastern parts of the Ring of Fire result from the collision of a few relatively large plates. The western parts of the Ring are more complex, with a number of large and small tectonic plates in collision.

In South America, the Ring of Fire is the result of the Antarctic Plate, the Nazca Plate and the Cocos Plate being subducted beneath the South American Plate. In Central America, the Cocos Plate is being subducted beneath the Caribbean Plate. A portion of the Pacific Plate and the small Juan de Fuca Plate are being subducted beneath the North American Plate. Along the northern portion, the northwestward-moving Pacific Plate is being subducted beneath the Aleutian Islands arc. Farther west, the Pacific Plate is being subducted at the Kamchatka Peninsula and Kuril arcs. Farther south, at Japan, Taiwan and the Philippines, the Philippine Plate is being subducted beneath the Eurasian Plate. The southwest section of the Ring of Fire is more complex, with a number of smaller tectonic plates in collision with the Pacific Plate at the Mariana Islands, the Philippines, eastern Indonesia, Papua New Guinea, Tonga, and New Zealand; this part of the Ring excludes Australia, because it lies in the center of its tectonic plate far from subduction zones.

Subduction zones and oceanic trenches

Chilean-type and Mariana-type subduction zones

If a tectonic plate's oceanic lithosphere is subducted beneath oceanic lithosphere of another plate, a volcanic island arc is created at the subduction zone. An example in the Ring of Fire is the Mariana Arc in the western Pacific Ocean. If, however, oceanic lithosphere is subducted under continental lithosphere, then a volcanic continental arc forms; a Ring of Fire example is the coast of Chile.

The steepness of the descending plate at a subduction zone depends on the age of the oceanic lithosphere that is being subducted. The older the oceanic lithosphere being subducted, the steeper the angle of descent of the subducted slab. As the Pacific's mid-ocean ridges, which are the source of its the oceanic lithosphere, are not actually in the middle of the ocean but located much closer to South America than to Asia, the oceanic lithosphere consumed at the South American subduction zones is younger and therefore subduction occurs at the South American coast at a relatively shallow angle. Older oceanic lithosphere is subducted in the western Pacific, with steeper angles of slab descent. This variation affects, for example, the location of volcanoes relative to the ocean trench, lava composition, type and severity of earthquakes, sediment accretion, and the amount of compression or tension. A spectrum of subduction zones exists between the Chilean and Mariana end members.

Oceanic trenches

Map of earthquake epicenters at the Kuril-Kamchatka trench and subduction zone

Oceanic trenches are the topographic expression of subduction zones on the floor of the oceans. Oceanic trenches associated with the Ring of Fire's subduction zones are:

• Peru–Chile Trench
• Middle America Trench
• Aleutian Trench
• Kuril–Kamchatka Trench
• Japan Trench
• Ryukyu Trench
• Izu-Bonin Trench
• Mariana Trench
• Yap Trench
• Philippine Trench
• Tonga Trench
• Kermadec Trench
• Hikurangi Trench

Gaps

Subduction zones around the Pacific Ocean do not form a complete ring. Where subduction zones are absent, there are corresponding gaps in subduction-related volcanic belts in the Ring of Fire. In some gaps there is no volcanic activity; in other gaps, volcanic activity does occur but it is caused by processes not related to subduction.

There are gaps in the Ring of Fire at some parts of the Pacific coast of the Americas. In some places, the gaps are thought to be caused by flat slab subduction; examples are the three gaps between the four sections of the Andean Volcanic Belt in South America. In North America, there is a gap in subduction-related volcanic activity in northern Mexico and southern California, due partly to a divergent boundary in the Gulf of California and due partly to the San Andreas Fault (a non-volcanic transform boundary). Another North American gap in subduction-related volcanic activity occurs in northern British Columbia, Yukon and south-east Alaska, where volcanism is caused by intraplate continental rifting.

Distribution of volcanoes

Distribution of Ring of Fire volcanoes active in the Holocene Epoch (last 11,700 years)

Continent	Country	Region	Volcanoes (subduction zone)	Volcanoes (other)	Comments	Consensus for inclusion
Antarctica		Antarctic Peninsula (Graham Land)	0	3 intraplate		No
Antarctica		South Shetland Islands	0	4 intraplate	intraplate rift volcanoes associated with back-arc rifting linked to subduction	No
South America	Chile		71	0	excluding Easter Island (oceanic rift)	Yes
South America	Chile-Argentina		18	0	border shared by two countries	Yes
South America	Argentina		15	4 intraplate	no coast on the Pacific Ocean	No
South America	Chile-Bolivia		6	0	border shared by two countries	Yes
South America	Bolivia		5	0	no coast on the Pacific Ocean	No
South America	Chile-Peru		1	0	border shared by two countries	Yes
South America	Peru		16	0		Yes
South America	Ecuador		21	0	excluding the Galapagos Islands (hotspot)	Yes
South America	Ecuador-Colombia		1	0	border shared by two countries	Yes
South America	Colombia		13	0		Yes
North America	Panama		2	0		Yes
North America	Costa Rica		10	0		Yes
North America	Nicaragua		17	0		Yes
North America	Honduras		4	0		Yes
North America	El Salvador		18	0		Yes
North America	El Salvador-Guatemala		2	0	border shared by two countries	Yes
North America	Guatemala		21	0		Yes
North America	Guatemala-Mexico		1	0	border shared by two countries	Yes
North America	Mexico		26	8 rift	excluding 3 oceanic rift volcanoes; 8 continental rift volcanoes in Baja California	Yes
North America	United States	California, Oregon, Washington	22	9 rift	9 continental rift volcanoes (6 in southern California and 3 in Oregon)	Yes
North America	Canada		6	16 intraplate	excluding 2 oceanic rift volcanoes	Yes
North America	United States	Alaska	80	4 intraplate in southeast Alaska	including 39 volcanoes in the Aleutian Islands; excluding 4 intraplate volcanoes in western Alaska far from subduction zone	Yes
Asia	Russia	Kamchatka	109	0	including 1 submarine volcano (Piip) in the Aleutian arc	Yes
Asia	Russia	Kuril Islands	44	0	including 3 submarine volcanoes; 15 volcanoes claimed by Japan	Yes
Asia	Japan		81	0	excluding the Izu Islands and the Bonin Islands	Yes
Asia	Taiwan		4	0	including 2 submarine volcanoes	Yes
	Japan	Izu Islands and Bonin Islands	26	0	including 13 submarine volcanoes	No
	United States	Northern Mariana Islands and Guam	25	0	including 16 submarine volcanoes	No
Asia	Philippines		41	0	including 1 submarine volcano	Yes
Asia	Indonesia	western islands	70		Sumatra (27 volcanoes), Krakatoa, Java (36 volcanoes), Bali (3 volcanoes), Lombok, Sumbawa and Sangeang (i.e. the Sunda Arc, north of the Sunda subduction zone between the Australian Plate and the Sunda Plate)	No
Asia	Indonesia	eastern islands	54		Sulawesi, Lesser Sunda Islands (excluding Bali, Lombok, Sumbawa and Sangeang), Halmahera, Banda Islands, Sangihe Islands	Yes
	Papua New Guinea		47	1 rift	including 2 submarine volcanoes	Yes
	Solomon Islands		8	0	including 4 submarine volcanoes	Yes
	Vanuatu		14	0		Yes
	claimed by Vanuatu and France (New Caledonia)		2	1 rift	Hunter Island and Matthew Island; East Gemini Seamount is a seamount at an oceanic rift	Yes
	Fiji		3	0		Yes
	France	Wallis and Futuna	1	0	mantle plume and subduction	No
	Samoa		2	0	mantle plume and subduction	No
	United States	American Samoa	4	0	mantle plume and subduction;including 1 submarine seamount	No
	Tonga		17	3 rift	including 13 submarine volcanoes, 3 of which are subduction-related back-arc rift volcanoes	Yes
	between Tonga and Kermadec Islands		1	0	Monowai submarine seamount (between the Exclusive Economic Zones of Tonga and New Zealand)	Yes
	New Zealand	Kermadec Islands	6	0	including 4 submarine volcanoes	Yes
	New Zealand		20	0	excluding the Kermadec Islands; including 8 submarine volcanoes	Yes
Total			955	59

Very large events

Volcanic eruptions

The four largest volcanic eruptions on Earth in the Holocene Epoch (the last 11,700 years) occurred at volcanoes in the Ring of Fire. They are the eruptions at Fisher Caldera (Alaska, 8700 BC), Kuril Lake (Kamchatka, 6450 BC), Kikai Caldera (Japan, 5480 BC) and Mount Mazama (Oregon, 5677 BC). More broadly, twenty of the twenty-five largest volcanic eruptions on Earth in this time interval occurred at Ring of Fire volcanoes.

Earthquakes

About 90% of the world's earthquakes and 81% of the world's largest earthquakes occur along the Ring of Fire. The next most seismically active region (5–6% of earthquakes and 17% of the world's largest earthquakes) is the Alpide belt, which extends from central Indonesia to the northern Atlantic Ocean via the Himalayas and southern Europe.

Between 1900 and 2016, most earthquakes of magnitude M_w ≥ 8.0 occurred in the Ring of Fire. They are presumed to have been megathrust earthquakes at subduction zones, including four of the most powerful earthquakes on Earth since modern seismological measuring equipment and magnitude measurement scales were introduced in the 1930s:

• 1960 Valdivia earthquake, Chile (magnitude M_w  9.4–9.6)
• 1964 Alaska earthquake, Alaska, United States (magnitude M_w  9.2)
• 2011 Tōhoku earthquake and tsunami, Japan (magnitude M_w  9.0–9.1)
• 1952 Severo-Kurilsk earthquake, Kamchatka, Russia (magnitude M_w  9.0)

Antarctica

Layers of phreatomagmatic tephra on Deception Island

Some geologists include the volcanoes of the South Shetland Islands, off the northern tip of the Antarctic Peninsula, as part of the Ring of Fire. These volcanoes, e.g. Deception Island, are due rifting in the Bransfield back-arc basin close to the South Shetland subduction zone. The Antarctic Peninsula (Graham Land) is also sometimes included in the Ring. Volcanoes south of the Antarctic Circle (e.g. the volcanoes of Victoria Land including Mount Erebus, and Mary Byrd Land), are not related to subduction; therefore, they are not part of the Ring of Fire.

The Balleny Islands, located between Antarctica and New Zealand, are volcanic but their volcanism is not related to subduction; therefore, they are not part of the Ring of Fire.

South America

Chile

Llaima's 2008 eruption

Chile has experienced numerous volcanic eruptions from about 90 volcanoes during the Holocene Epoch.

Villarrica is one of Chile's most active volcanoes, rising above the lake and town of the same name. It is the westernmost of three large stratovolcanoes that trend perpendicular to the Andes along the Gastre Fault. Villarrica, along with Quetrupillán and the Chilean part of Lanín, are protected within Villarrica National Park.

Villarrica, with its lava of basaltic-andesitic composition, is one of only five volcanoes worldwide known to have an active lava lake within its crater. The volcano usually generates strombolian eruptions, with ejection of incandescent pyroclasts and lava flows. Melting of snow and glacier ice, as well as rainfall, often causes lahars, such as during the eruptions of 1964 and 1971.

A 2-kilometre-wide (1.2 mi) postglacial caldera is located at the base of the presently active dominantly basaltic-to-andesitic cone at the northwest margin of the Pleistocene caldera. About 25 scoria cones dot Villarica's flanks. Plinian eruptions and pyroclastic flows have been produced during the Holocene from this dominantly basaltic volcano, but historical eruptions have consisted of largely mild-to-moderate explosive activity with occasional lava effusion. Lahars from the glacier-covered volcanoes have damaged towns on its flanks.

The Llaima Volcano is one of the largest and most active volcanoes in Chile. It is situated 82 km (51 mi) northeast of Temuco and 663 km (412 mi) southeast of Santiago, within the borders of Conguillío National Park. Llaima's activity has been documented since the 17th century, and consists of several separate episodes of moderate explosive eruptions with occasional lava flows.

Lascar erupting in 2006

Lascar is a stratovolcano and the most active volcano of the northern Chilean Andes. The largest eruption of Lascar took place about 26,500 years ago, and following the eruption of the Tumbres scoria flow about 9,000 years ago, activity shifted back to the eastern edifice, where three overlapping craters were formed. Frequent small-to-moderate explosive eruptions have been recorded from Lascar in historical time since the mid-19th century, along with periodic larger eruptions that produced ash and tephra fall up to hundreds of kilometers away from the volcano. The largest eruption of Lascar in recent history took place in 1993, producing pyroclastic flows as far as 8.5 km (5 mi) northwest of the summit and ash fall in Buenos Aires, Argentina, more than 1,600 km (994 mi) to the southeast. The latest series of eruptions began on April 18, 2006 and was continuing as of 2011.

Chiliques is a stratovolcano located in the Antofagasta Region of Chile, immediately north of Cerro Miscanti. Laguna Lejía lies to the north of the volcano and has been dormant for at least 10,000 years, but is now showing signs of life. A January 6, 2002, nighttime thermal infrared image from ASTER revealed a hot spot in the summit crater, as well as several others along the upper flanks of the volcano's edifice, indicating new volcanic activity. Examination of an earlier nighttime thermal infrared image from May 24, 2000, showed no such hot spots.

Calbuco is a stratovolcano in southern Chile, located southeast of Llanquihue Lake and northwest of Chapo Lake, in Los Lagos Region. The volcano and the surrounding area are protected within Llanquihue National Reserve. It is a very explosive andesite volcano that underwent edifice collapse in the late Pleistocene, producing a volcanic debris avalanche that reached the lake. At least nine eruptions occurred since 1837, with the latest one in 1972. One of the largest historical eruptions in southern Chile took place there in 1893–1894. Violent eruptions ejected 30 cm (12 in) bombs to distances of 8 km (5.0 mi) from the crater, accompanied by voluminous hot lahars. Strong explosions occurred in April 1917, and a lava dome formed in the crater accompanied by hot lahars. Another short explosive eruption in January 1929 also included an apparent pyroclastic flow and a lava flow. The last major eruption of Calbuco, in 1961, sent ash columns 12–15 km (7.5–9.3 mi) high and produced plumes that dispersed mainly to the southeast and two lava flows were also emitted. A minor, four-hour eruption happened on August 26, 1972. Strong fumarolic emission from the main crater was observed on August 12, 1996.

Lonquimay is a stratovolocano of late-Pleistocene to dominantly Holocene age, with the shape of a truncated cone. The cone is largely andesitic, though basaltic and dacitic rocks are present. It is located in La Araucanía Region of Chile, immediately southeast of Tolhuaca volcano. Sierra Nevada and Llaima are their neighbors to the south. The snow-capped volcano lies within the protected area Malalcahuello-Nalcas. The volcano last erupted in 1988, ending in 1990. The VEI was 3. The eruption was from a flank vent and involved lava flows and explosive eruptions. Some fatalities occurred.

The volcanoes in Chile are monitored by the National Geology and Mining Service (SERNAGEOMIN).

Earthquake activity in Chile is related to subduction of the Nazca Plate to the east. Chile notably holds the record for the largest earthquake ever recorded, the 1960 Valdivia earthquake.More recently, a magnitude-8.8 earthquake struck central Chile on February 27, 2010, the Puyehue-Cordón Caulle volcano erupted in 2011, and a M8.2 earthquake struck northern Chile on April 1, 2014. The main shock was preceded by a number of moderate to large shocks and was followed by a large number of moderate to very large aftershocks, including a magnitude-7.6 event on April 2.

Bolivia

Bolivia hosts active and extinct volcanoes across its territory. The active volcanoes are located in western Bolivia where they make up the Cordillera Occidental, the western limit of the Altiplano plateau. Some of the active volcanoes are international mountains shared with Chile. All Cenozoic volcanoes of Bolivia are part of the Central Volcanic Zone (CVZ) of the Andean Volcanic Belt that results due to processes involved in the subduction of the Nazca Plate under the South American Plate. The Central Volcanic Zone is a major late Cenozoic volcanic province.

Peru

Sabancaya is an active 5,976-metre (19,606 ft) stratovolcano in the Andes of southern Peru, about 100 km (62 mi) northwest of Arequipa. It is the most active volcano in Peru, with an ongoing eruption that started in 2016.

Ubinas is another active volcano of 5,672-metre (18,609 ft) in southern Peru; its most recent eruption occurred in 2019.

Volcanoes in Peru are monitored by the Peruvian Geophysical Institute.

Ecuador

Tungurahua erupting molten lava at night (1999)

Cotopaxi is a stratovolcano in the Andes, located about 50 km (31 mi) south of Quito, Ecuador, South America. It is the second-highest summit in the country, reaching a height of 5,897 m (19,347 ft). Since 1738, Cotopaxi has erupted more than 50 times, resulting in the creation of numerous valleys formed by mudflows around the volcano.

In October 1999, Pichincha Volcano erupted in Quito and covered the city with several inches of ash. Prior to that, the last major eruptions were in 1553 and in 1660, when about 30 cm of ash fell on the city.

At 5,230-metre (17,160 ft), Sangay Volcano is an active stratovolcano in central Ecuador, one of the highest active volcanoes in the world and is one of Ecuador's most active volcanoes. It exhibits mostly strombolian activity; An eruption, which started in 1934, ended in 2011. More recent eruptions have occurred. Geologically, Sangay marks the southern bound of the Northern Volcanic Zone, and its position straddling two major pieces of crust accounts for its high level of activity. Sangay's roughly 500,000-year history is one of instability; two previous versions of the mountain were destroyed in massive flank collapses, evidence of which still litters its surroundings today. Sangay is one of two active volcanoes located within the namesake Sangay National Park, the other being Tungurahua to the north. As such, it has been listed as a UNESCO World Heritage Site since 1983.

Reventador is an active stratovolcano that lies in the eastern Andes of Ecuador. Since 1541, it has erupted over 25 times, with its most recent eruption starting in 2008 and, as of 2020, still ongoing, but the largest historical eruption occurred in 2002. During that eruption, the plume from the volcano reached a height of 17 km (11 mi), and pyroclastic flows reached 7 km (4.3 mi) from the cone. On March 30, 2007, the volcano erupted ash again, which reached a height of about 3.2 km (2 mi).

In Ecuador, EPN monitors volcanic activity.

North America

Central America

Crater of Poás volcano in Costa Rica, 2004

 

Santiaguito Volcano, 2003 eruption in Guatemala

Costa Rica

Poás Volcano is an active 2,708-metre (8,885 ft) stratovolcano located in central Costa Rica; it has erupted 39 times since 1828.

The Volcanological and Seismological Observatory of Costa Rica (OVSICORI, Observatorio Vulcanológico y Sismológico de Costa Rica) at the National University of Costa Rica has a dedicated team in charge of researching and monitoring the volcanoes, earthquakes, and other tectonic processes in the Central America Volcanic Arc.

Guatemala

In 1902, the Santa Maria Volcano erupted violently in Guatemala, with the largest explosions occurring over two days, ejecting an estimated 5.5 km³ (1.3 cu mi) of magma. The eruption was one of the largest of the 20th century, only slightly less in magnitude to that of Mount Pinatubo in 1991. The eruption had a volcanic explosivity index of 6. Today, Santiaguito is one of the world's most active volcanoes.

North American Cordillera

Mexico

The Trans-Mexican Volcanic Belt

Volcanoes of Mexico related to subduction of the Cocos and Rivera plates occur in the Trans-Mexican Volcanic Belt, which extends 900-kilometre (560 mi) from west to east across central-southern Mexico. Popocatépetl, lying in the eastern half of the Trans-Mexican Volcanic Belt, is the second-highest peak in Mexico after the Pico de Orizaba. It is one of the most active volcanoes in Mexico, having had more than 20 major eruptions since the arrival of the Spanish in 1519. The 1982 eruption of El Chichón, which killed about 2,000 people who lived near the volcano, created a 1-km-wide caldera that filled with an acidic crater lake. Before 1982, this relatively unknown volcano was heavily forested and of no greater height than adjacent nonvolcanic peaks.

United States

Area of the Cascadia subduction zone, including the Cascade Volcanic Arc (red triangles)

The Cascade Volcanic Arc lies in the western United States. This arc includes nearly 20 major volcanoes, among a total of over 4,000 separate volcanic vents including numerous stratovolcanoes, shield volcanoes, lava domes, and cinder cones, along with a few isolated examples of rarer volcanic forms such as tuyas. Volcanism in the arc began about 37 million years ago, but most of the present-day Cascade volcanoes are less than 2 million years old, and the highest peaks are less than 100,000 years old. The arc is formed by the subduction of the Gorda and Juan de Fuca plates at the Cascadia subduction zone. This is a 1,090-kilometre (680 mi) long fault, running 80 km (50 mi) off the coast of the Pacific Northwest from northern California to Vancouver Island, British Columbia. The plates move at a relative rate of over 10 mm (0.4 in) per year at an oblique angle to the subduction zone.

Because of the very large fault area, the Cascadia subduction zone can produce very large earthquakes, magnitude 9.0 or greater, if rupture occurred over its whole area. When the "locked" zone stores energy for an earthquake, the "transition" zone, although somewhat plastic, can rupture. Thermal and deformation studies indicate that the locked zone is fully locked for 60 km (37 mi) down-dip from the deformation front. Further down-dip, a transition from fully locked to aseismic sliding occurs.

American Cascade Range volcano eruptions in the last 4000 years

Unlike most subduction zones worldwide, no oceanic trench is present along the continental margin in Cascadia. Instead, terranes and the accretionary wedge have been lifted up to form a series of coast ranges and exotic mountains. A high rate of sedimentation from the outflow of the three major rivers (Fraser River, Columbia River, and Klamath River) which cross the Cascade Range contributes to further obscuring the presence of a trench. However, in common with most other subduction zones, the outer margin is slowly being compressed, similar to a giant spring. When the stored energy is suddenly released by slippage across the fault at irregular intervals, the Cascadia subduction zone can create very large earthquakes such as the magnitude-9 Cascadia earthquake of 1700. Geological evidence indicates that great earthquakes may have occurred at least seven times in the last 3,500 years, suggesting a return time of 400 to 600 years. Also, evidence of accompanying tsunamis with every earthquake is seen, as the prime reason these earthquakes are known is through "scars" the tsunamis left on the coast, and through Japanese records (tsunami waves can travel across the Pacific).

The 1980 eruption of Mount St. Helens was the most significant to occur in the contiguous 48 U.S. states in recorded history (VEI = 5, 1.3 km³ (0.3 cu mi) of material erupted), exceeding the destructive power and volume of material released by the 1915 eruption of California's Lassen Peak. The eruption was preceded by a two-month series of earthquakes and steam-venting episodes caused by an injection of magma at shallow depth below the mountain that created a huge bulge and a fracture system on Mount St. Helens' north slope. An earthquake at 8:32 am on May 18, 1980, caused the entire weakened north face to slide away, suddenly exposing the partly molten, gas-rich rock in the volcano to lower pressure. The rock responded by exploding into a very hot mix of pulverized lava and older rock that sped toward Spirit Lake so fast that it quickly passed the avalanching north face.

Alaska is known for its seismic and volcanic activity, holding the record for the second-largest earthquake in the world, the Good Friday earthquake, and having more than 50 volcanoes which have erupted since about 1760. Volcanoes are found not only in the mainland, but also in the Aleutian Islands.

The United States Geological Survey and the National Earthquake Information Center monitor volcanoes and earthquakes in the United States.

Canada

Map of young volcanoes in Western Canada

British Columbia and Yukon are home to a region of volcanoes and volcanic activity in the Pacific Ring of Fire. More than 20 volcanoes have erupted in the western Canada during the Holocene Epoch but only 6 are directly related to subduction: Bridge River Cones, Mount Cayley massif, Mount Garibaldi, Garibaldi Lake, Silverthrone Caldera, and Mount Meager massif. Several mountains in populated areas of British Columbia are dormant volcanoes. Most of these were active during the Pleistocene and Holocene epochs. Although none of Canada's volcanoes are currently erupting, several volcanoes, volcanic fields, and volcanic centers are considered potentially active. There are hot springs at some volcanoes. Since 1975, seismic activity appears to have been associated with some volcanoes in British Columbia including the six subduction-related volcanoes as well as intraplate volcanoes such as Wells Gray-Clearwater volcanic field. The volcanoes are grouped into five volcanic belts with different tectonic settings.

The Northern Cordilleran Volcanic Province is an area of numerous volcanoes, which are caused by continental rifting not subduction; therefore geologists often regard it as a gap in the Pacific Ring of Fire between the Cascade Volcanic Arc further south and Alaska's Aleutian Arc further north.

The Garibaldi Volcanic Belt in southwestern British Columbia is the northern extension of the Cascade Volcanic Arc in the United States (which includes Mount Baker and Mount St. Helens) and contains the most explosive young volcanoes in Canada. It formed as a result of subduction of the Juan de Fuca Plate (a remnant of the much larger Farallon Plate) under the North American Plate along the Cascadia subduction zone. The Garibaldi Volcanic Belt includes the Bridge River Cones, Mount Cayley massif, Mount Fee, Mount Garibaldi, Mount Price, Mount Meager massif, the Squamish Volcanic Field, and more smaller volcanoes. The eruption styles in the belt range from effusive to explosive, with compositions from basalt to rhyolite. Morphologically, centers include calderas, cinder cones, stratovolcanoes and small isolated lava masses. Due to repeated continental and alpine glaciations, many of the volcanic deposits in the belt reflect complex interactions between magma composition, topography, and changing ice configurations. The most recent major catastrophic eruption in the Garibaldi Volcanic Belt was an explosive eruption of the Mount Meager massif about 2,350 years ago. It was similar to the 1980 eruption of Mount St. Helens, sending an ash column about 20 km into the stratosphere.

The Mount Meager massif as seen from the east near Pemberton, British Columbia: Summits left to right are Capricorn Mountain, Mount Meager, and Plinth Peak.

The Chilcotin Group is a north–south range of volcanoes in southern British Columbia running parallel to the Garibaldi Volcanic Belt. The majority of the eruptions in this belt happened either 6–10 million years ago (Miocene) or 2–3 million years ago (Pliocene), although with some slightly more recent eruptions (in the Pleistocene). It is thought to have formed as a result of back-arc extension behind the Cascadia subduction zone. Volcanoes in this belt include Mount Noel, the Clisbako Caldera Complex, Lightning Peak, Black Dome Mountain, and many lava flows.

Eruptions of basaltic to rhyolitic volcanoes and hypabyssal rocks of the Alert Bay Volcanic Belt in northern Vancouver Island are probably linked with the subducted margin flanked by the Explorer and Juan de Fuca Plates at the Cascadia subduction zone. It appears to have been active during the Pliocene and Pleistocene. However, no Holocene eruptions are known, and volcanic activity in the belt has likely ceased.

The active Queen Charlotte Fault on the west coast of the Haida Gwaii, British Columbia, has generated three large earthquakes during the 20th century: a magnitude 7 event in 1929; a magnitude 8.1 in 1949 (Canada's largest recorded earthquake); and a magnitude 7.4 in 1970.

The Public Safety Geo-science Program at the Natural Resources Canada undertakes research to support risk reduction from the effects of space weather, earthquakes, tsunamis, volcanoes, and landslides.

Asia

Russia

Kambalny, an active volcano in the Kamchatka Peninsula

The Kamchatka Peninsula in the Russian Far East is one of the most active volcanic areas in the world, with 20 historically active volcanoes. It lies between the Pacific Ocean to the east and the Okhotsk Sea to the west. Immediately offshore along the Pacific coast of the peninsula runs the 10,500-metre-deep (34,400 ft) Kuril-Kamchatka Trench, where subduction of the Pacific Plate fuels the volcanism. Several types of volcanic activity are present, including stratovolcanoes, shield volcanoes, Hawaiian-style fissure eruptions and geysers.

Active, dormant and extinct volcanoes of Kamchatka are in two major volcanic belts. The most recent activity takes place in the eastern belt, starting in the north at the Shiveluch volcanic complex, which lies at the junction of the Aleutian and Kamchatka volcanic arcs. Just to the south is the famous Klyuchi volcanic group, comprising the twin volcanic cones of Kliuchevskoi and Kamen, the huge volcanic complexes of Tolbachik and Ushkovsky, and a number of other large stratovolcanoes. The only active volcano in the central belt is found west of here, the huge remote Ichinsky. Farther south, the eastern belt of stratovolcanoes continues to the southern tip of Kamchatka, continuing onto the Kuril Islands, with their 32 historically active volcanoes.

Japan

About 10% of the world's active volcanoes are found in Japan, which lies in a zone of extreme crustal instability. They are formed by subduction of the Pacific Plate and the Philippine Sea Plate. As many as 1,500 earthquakes are recorded yearly, and magnitudes of 4 to 6 are not uncommon. Minor tremors occur almost daily in one part of the country or another, causing some slight shaking of buildings. Major earthquakes occur infrequently; the most famous in the 20th century were: the Great Kantō earthquake of 1923, in which 130,000 people died; and the Great Hanshin earthquake of January 17, 1995, in which 6,434 people died. On March 11, 2011 a magnitude 9.0 earthquake hit Japan, the country's biggest ever and the fifth largest on record, according to US Geological Survey data. Undersea earthquakes also expose the Japanese coastline to danger from tsunamis.

Mount Fuji at sunrise from Lake Kawaguchi

Mount Bandai, one of Japan's most noted volcanoes, rises above the north shore of Lake Inawashiro. Mount Bandai is formed of several overlapping stratovolcanoes, the largest of which is O-Bandai, constructed within a horseshoe-shaped caldera that formed about 40,000 years ago when an earlier volcano collapsed, forming the Okinajima debris avalanche, which traveled to the southwest and was accompanied by a plinian eruption. Four major phreatic eruptions have occurred during the past 5,000 years, two of them in historical time, in 806 and 1888. Seen from the south, Bandai presents a conical profile, but much of the north side of the volcano is missing as a result of the collapse of Ko-Bandai volcano during the 1888 eruption, in which a debris avalanche buried several villages and formed several large lakes. In July 1888, the north flank of Mount Bandai collapsed during an eruption quite similar to the May 18, 1980, eruption of Mount St. Helens. After a week of seismic activity, a large earthquake on July 15, 1888, was followed by a tremendous noise and a large explosion. Eyewitnesses heard about 15 to 20 additional explosions and observed that the last one was projected almost horizontally to the north.

Mount Fuji is Japan's highest and most noted volcano, featuring heavily in Japanese culture and serving as one of the country's most popular landmarks. The modern postglacial stratovolcano is constructed above a group of overlapping volcanoes, remnants of which form irregularities on Fuji's profile. Growth of the younger Mount Fuji began with a period of voluminous lava flows from 11,000 to 8,000 years ago, accounting for four-fifths of the volume of the younger Mount Fuji. Minor explosive eruptions dominated activity from 8,000 to 4,500 years ago, with another period of major lava flows occurring from 4,500 to 3,000 years ago. Subsequently, intermittent major explosive eruptions occurred, with subordinate lava flows and small pyroclastic flows. Summit eruptions dominated from 3,000 to 2,000 years ago, after which flank vents were active. The extensive basaltic lava flows from the summit and some of the more than 100 flank cones and vents blocked drainage against the Tertiary Misaka Mountains on the north side of the volcano, forming the Fuji Five Lakes. The last eruption of this dominantly basaltic volcano in 1707 ejected andesitic pumice and formed a large new crater on the east flank. Some minor volcanic activity may occur in the next few years.

Philippines

Map showing major volcanoes of the Philippines

The 1991 eruption of Mount Pinatubo is the world's second-largest eruption of the 20th century. Successful predictions of the onset of the climactic eruption led to the evacuation of tens of thousands of people from the surrounding areas, saving many lives, but as the surrounding areas were severely damaged by pyroclastic flows, ash deposits, and later, lahars caused by rainwater remobilising earlier volcanic deposits, thousands of houses were destroyed.

Mayon Volcano overlooks a pastoral scene about five months before the volcano's violent eruption in September 1984.

Mayon Volcano is the Philippines' most active volcano. It has steep upper slopes that average 35–40° and is capped by a small summit crater. The historical eruptions of this basaltic-andesitic volcano date back to 1616 and range from Strombolian to basaltic Plinian eruptions. Eruptions occur predominately from the central conduit and have also produced lava flows that travel far down the flanks. Pyroclastic flows and mudflows have commonly swept down many of the roughly 40 ravines that radiate from the summit and have often devastated populated lowland areas.

Taal Volcano has had 33 recorded eruptions since 1572. A devastating eruption occurred in 1911, which claimed more than a thousand lives. The deposits of that eruption consist of a yellowish, fairly decomposed (nonjuvenile) tephra with a high sulfur content. The most recent period of activity lasted from 1965 to 1977, and was characterized by the interaction of magma with the lake water, which produced violent phreatic and phreatomagmatic eruptions. The volcano was dormant from 1977 then showed signs of unrest since 1991 with strong seismic activity and ground-fracturing events, as well as the formation of small mud geysers on parts of the island. An eruption occurred in January 2020.

Kanlaon Volcano, the most active volcano in the central Philippines, has erupted 25 times since 1866. Eruptions are typically phreatic explosions of small-to-moderate size that produce minor ash falls near the volcano. On August 10, 1996, Kanlaon erupted without warning, killing 3 persons who were among 24 mountain climbers trapped near the summit.

Indonesia

Major volcanoes in Indonesia

Indonesia is located where the Ring of Fire around the Pacific Ocean meets the Alpide belt (which runs from Southeast Asia to Southwest Europe).

The eastern islands of Indonesia (Sulawesi, the Lesser Sunda Islands (excluding Bali, Lombok, Sumbawa and Sangeang), Halmahera, the Banda Islands and the Sangihe Islands) are geologically associated with subduction of the Pacific Plate or its related minor plates and, therefore, the eastern islands are often regarded as part of the Ring of Fire.

The western islands of Indonesia (the Sunda Arc of Sumatra, Krakatoa, Java, Bali, Lombok, Sumbawa and Sangeang) are located north of a subduction zone in the Indian Ocean. Although news media, popular science publications and some geologists include the western islands (and their notable volcanoes such as Krakatoa, Merapi, Tambora and Toba) in the Ring of Fire, geologists often exclude the western islands from the Ring; instead the western islands are often included in the Alpide belt.

Islands in the southwest Pacific Ocean

Papua New Guinea and tectonic plates: Pacific Plate, Australian Plate, Caroline Plate, Banda Sea Plate (as "Mer de Banda"), Woodlark Plate, Bird's Head Plate, Maoke Plate, Solomon Sea Plate, North Bismarck Plate, South Bismarck Plate and Manus Plate (in French)

Volcanic eruption at West Mata submarine volcano between Samoa and Tonga, 2010

Major volcanoes of New Zealand

 

View of Mount Taranaki from Stratford.

New Zealand contains the world's strongest concentration of youthful rhyolitic volcanoes, and voluminous sheets of tuff blanket much of the North Island. The earliest historically-dated eruption was at Whakaari/White Island in 1826, followed in 1886 by the country's largest historical eruption at Mount Tarawera. Much of the region north of New Zealand's North Island is made up of seamounts and small islands, including 16 submarine volcanoes. In the last 1.6 million years, most of New Zealand's volcanism is from the Taupo Volcanic Zone.

Mount Ruapehu, at the southern end of the Taupo Volcanic Zone, is one of the most active volcanoes in New Zealand. It began erupting at least 250,000 years ago. In recorded history, major eruptions have been about 50 years apart, in 1895, 1945, and 1995–1996. Minor eruptions are frequent, with at least 60 since 1945. Some of the minor eruptions in the 1970s generated small ash falls and lahars that damaged ski fields. Between major eruptions, a warm acidic crater lake forms, fed by melting snow. Major eruptions may completely expel the lake water. Where a major eruption has deposited a tephra dam across the lake's outlet, the dam may collapse after the lake has refilled and risen above the level of its normal outlet, the outrush of water causing a large lahar. The most notable lahar caused the Tangiwai disaster on December 24, 1953, when 151 people aboard a Wellington to Auckland express train were killed after the lahar destroyed the Tangiwai rail bridge just moments before the train was due. In 2000, the ERLAWS system was installed on the mountain to detect such a collapse and alert the relevant authorities.

The Auckland volcanic field on the North Island of New Zealand has produced a diverse array of explosive craters, scoria cones, and lava flows. Currently dormant, the field is likely to erupt again with the next "hundreds to thousands of years", a very short timeframe in geologic terms. The field contains at least 40 volcanoes, most recently active about 600 years ago at Rangitoto Island, erupting 2.3 km³ (0.55 cu mi) of lava.

Soil

The soils of the Pacific Ring of Fire include andosols, also known as andisols, created by the weathering of volcanic ash. They contain large proportions of volcanic glass. The Ring of Fire is the world's main location for this soil type, which typically has good levels of fertility.

Regional effects of climate change

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Regional_effects_of_climate_change 

Average global temperatures from 2010 to 2019 compared to a baseline average from 1951 to 1978. Source: NASA.

Regional effects of climate change are long-term significant changes in the expected patterns of average weather of a specific region due to climate change. The world average temperature is rising due to the greenhouse effect caused by increasing levels of greenhouse gases, especially carbon dioxide. When the global temperature changes, the changes in climate are not expected to be uniform across the Earth. In particular, land areas change more quickly than oceans, and northern high latitudes change more quickly than the tropics, and the margins of biome regions change faster than do their cores.

Regional effects of climate change vary in nature. Some are the result of a generalised global change, such as rising temperature, resulting in local effects, such as melting ice. In other cases, a change may be related to a change in a particular ocean current or weather system. In such cases, the regional effect may be disproportionate and will not necessarily follow the global trend. The increasing temperatures from greenhouse gases have been causing sea levels to rise for many years.

There are three major ways in which global warming will make changes to regional climate: melting or forming ice, changing the hydrological cycle (of evaporation and precipitation) and changing currents in the oceans and air flows in the atmosphere. The coast can also be considered a region, and will suffer severe impacts from sea level rise.

CMIP5 average of climate model projections for 2081–2100 relative to 1986–2005, under low and high emission scenarios.

The Arctic, Africa, small islands and Asian megadeltas are regions that are likely to be especially affected by future climate change. Africa is one of the most vulnerable continents to climate variability and change because of multiple existing stresses and low adaptive capacity. Climate change is projected to decrease freshwater availability in central, south, east and southeast Asia, particularly in large river basins. With population growth and increasing demand from higher standards of living, this decrease could adversely affect more than a billion people by the 2050s. Small islands, whether located in the tropics or higher latitudes, are already exposed to extreme weather events and changes in sea level. This existing exposure will likely make these areas sensitive to the effects of climate change.

Past and projected Köppen-Geiger climate classification maps.

Background

With very high confidence, scientists have concluded that physical and biological systems on all continents and in most oceans had been affected by recent climate changes, particularly regional temperature increases. Impacts include changes in regional rainfall patterns, earlier leafing of trees and plants over many regions; movements of species to higher latitudes and altitudes in the Northern Hemisphere; changes in bird migrations in Europe, North America and Australia; and shifting of the oceans' plankton and fish from cold- to warm-adapted communities.

The human influence on the climate can be seen in the geographical pattern of observed warming, with greater temperature increases over land and in polar regions rather than over the oceans. Using models, it is possible to identify the human "signal" of global warming over both land and ocean areas.

Regional impacts

Highlights of recent and projected regional impacts are shown below:

Impacts on Africa

African countries are more affected by climate change because of the dependence on agriculture as well as their poor financial, technical and institutional capacity to adapt.

• Africa is one of the most vulnerable continents to climate variability and change because of multiple existing stresses and low adaptive capacity. Existing stresses include poverty, political conflicts, and ecosystem degradation.
• By 2050, between 350 million and 601 million people are projected to experience increased water stress due to climate change.
• Climate change is likely to lead to the increasing frequency and severity of Intense rainfall events across Africa. Since the 1980s climate change has resulted in the tripling in the frequency of extreme storms in the Sahel region of West Africa.
• Climate variability and change is projected to severely compromise agricultural production, including access to food, across Africa, which means there will be high food insecurity.
• Climate change can influence pest infestation and spread of animal disease because of increase in temperature and rainfall variability
• Toward the end of the 21st century, projected sea level rise will likely affect low-lying coastal areas with large populations
• Climate variability and change can negatively impact human health. In many African countries, other factors already threaten human health. For example, malaria threatens health in southern Africa and the Eastern Highlands.

Impacts on Arctic and Antarctic

• Climate change in the Arctic will likely reduce the thickness and extent of glaciers and ice sheets.
• Changes in natural ecosystems will likely have detrimental effects on many organisms including migratory birds, mammals, and higher predators. Climate change will likely cause changes in dominance structures in plant communities, with shrubs expanding.
• In the Arctic, climate changes will likely reduce the extent of sea ice and permafrost, which can have mixed effects on human settlements. Negative impacts could include damage to infrastructure and changes to winter activities such as ice fishing and ice road transportation. Positive impacts could include more navigable northern sea routes.
• Continued permafrost degradation will likely result in unstable infrastructure in Arctic regions, or Alaska before 2100. Thus, impacting roads, pipelines and buildings, as well as water distribution, and cause slope failures.
• The reduction and melting of permafrost, sea level rise, and stronger storms may worsen coastal erosion.
• Terrestrial and marine ecosystems and habitats are projected to be at risk to invasive species, as climatic barriers are lowered in both polar regions.

Impacts on Asia

• Glaciers in Asia are melting at a faster rate than ever documented in historical records. Melting glaciers increase the risks of flooding and rock avalanches from destabilized slopes.
• Climate change is projected to decrease freshwater availability in central, south, east and southeast Asia, particularly in large river basins. With population growth and increasing demand from higher standards of living, this decrease could adversely affect more than a billion people by the 2050s.
• Increased flooding from the sea and, in some cases, from rivers, threatens coastal areas, especially heavily populated delta regions in south, east, and southeast Asia.
• By the mid-21st century, crop yields could increase up to 20% in east and southeast Asia. In the same period, yields could decrease up to 30% in central and south Asia.
• Sickness and death due to diarrhoeal disease are projected to increase in east, south, and southeast Asia due to projected changes in the hydrological cycle associated with climate change.
• Agricultural demand from China's crops lead to land degradation and land modifications which in turn leads to increased greenhouse gas emissions. Environmental factor#Socioeconomic Drivers

Impacts on Europe

• Wide-ranging impacts of climate change have already been documented in Europe. These impacts include retreating glaciers, longer growing seasons, species range shifts, and heat wave-related health impacts.
• Future impacts of climate change are projected to negatively affect nearly all European regions. Many economic sectors, such as agriculture and energy, could face challenges.
• In southern Europe, higher temperatures and drought may reduce water availability, hydropower potential, summer tourism, and crop productivity.
• In central and eastern Europe, summer precipitation is projected to decrease, causing higher water stress. Forest productivity is projected to decline. The frequency of peatland fires is projected to increase.
• In northern Europe, climate change is initially projected to bring mixed effects, including some benefits such as reduced demand for heating, increased crop yields, and increased forest growth. However, as climate change continues, negative impacts are likely to outweigh benefits. These include more frequent winter floods, endangered ecosystems, and increasing ground instability.

Impacts on South America

• By mid-century, increases in temperature and decreases in soil moisture are projected to cause savanna to gradually replace tropical forest in the eastern Amazon basin.
• In drier areas, climate change will likely worsen drought, leading to salinization (increased salt content) and desertification (land degradation) of agricultural land. The productivity of livestock and some important crops such as maize and coffee are projected to decrease, with adverse consequences for food security. In temperate zones, soybean yields are projected to increase.
• Sea level rise is projected to increase risk of flooding, displacement of people, salinization of drinking water resources, and coastal erosion in low-lying areas.
• Changes in precipitation patterns and the melting of glaciers are projected to significantly affect water availability for human consumption, agriculture, and energy generation.

Impacts on North America

Projected change in seasonal mean surface air temperature from the late 20th century (1971-2000 average) to the middle 21st century (2051-2060). The left panel shows changes for June–July–August (JJA) seasonal averages, and the right panel shows changes for December–January–February (DJF). The change is in response to increasing atmospheric concentrations of greenhouse gases and aerosols based on a "middle of the road" estimate of future emissions (SRES emissions scenario A1B). Warming is projected to be larger over continents than oceans, and is largest at high latitudes of the Northern Hemisphere during Northern Hemisphere winter (DJF) (Credit: NOAA Geophysical Fluid Dynamics Laboratory).

• Warming in western mountains is projected to decrease snowpack, increase winter flooding, and reduce summer flows, exacerbating competition for over-allocated water resources.
• Disturbances from pests, diseases, and fire are projected to increasingly affect forests, with extended periods of high fire risk and large increases in area burned.
• Moderate climate change in the early decades of the century is projected to increase aggregate yields of rain-fed agriculture by 5-20%, but with important variability among regions. Crops that are near the warm end of their suitable range or that depend on highly utilized water resources will likely face major challenges.
• Increases in the number, intensity, and duration of heat waves during the course of the century are projected to further challenge cities that currently experience heat waves, with potential for adverse health impacts. Older populations are most at risk.
• Climate change will likely increasingly stress coastal communities and habitats, worsening the existing stresses of development and pollution.

As to 2019, climate change have already increased wildfires frequency and power in Canada, especially in Alberta.

Impacts on Oceania

• Water security problems are projected to intensify by 2030 in southern and eastern Australia, and in the northern and some eastern parts of New Zealand.
• Significant loss of biodiversity is projected to occur by 2020 in some ecologically rich sites, including the Great Barrier Reef and the Wet Tropics of Queensland.
• Sea level rise and more severe storms and coastal flooding will likely impact coastal areas. Coastal development and population growth in areas such as Cairns and Southeast Queensland (Australia) and Northland to Bay of Plenty (New Zealand), would place more people and infrastructure at risk.
• By 2030, increased drought and fire is projected to cause declines in agricultural and forestry production over much of southern and eastern Australia and parts of eastern New Zealand.
• Extreme storm events are likely to increase failure of floodplain protection and urban drainage and sewerage, as well as damage from storms and fires.
• More heat waves may cause more deaths and more electrical blackouts.

Impacts on small islands

• Small islands, whether located in the tropics or higher latitudes, are already exposed to extreme weather events and changes in sea level. This existing exposure will likely make these areas sensitive to the effects of climate change.
• Deterioration in coastal conditions, such as beach erosion and coral bleaching, will likely affect local resources such as fisheries, as well as the value of tourism destinations.
• Sea level rise is projected to worsen inundation, storm surge, erosion, and other coastal hazards. These impacts would threaten vital infrastructure, settlements, and facilities that support the livelihood of island communities.
• By mid-century, on many small islands (such as the Caribbean and Pacific), climate change is projected to reduce already limited water resources to the point that they become insufficient to meet demand during low-rainfall periods.
• Invasion by non-native species is projected to increase with higher temperatures, particularly in mid- and high-latitude islands.

Inundation, displacement, and national sovereignty of small islands

According to scholar Tsosie, environmental disparities among disadvantaged communities including poor and racial minorities, extend to global inequalities between the developed and developing countries. For example, according to Barnett, J. and Adger, W.N. the projected damage to small islands and atoll communities will be a consequence of climate change caused by developing countries that will disproportionately affect these developing nations.

Sea-level rise and increased tropical cyclones are expected to place low-lying small islands in the Pacific, Indian, and Caribbean regions at risk of inundation and population displacement.

According to N. Mimura's study on the vulnerability of island countries in the South Pacific to sea level rise and climate change, financially burdened island populations living in the lowest-lying regions are most vulnerable to risks of inundation and displacement. On the islands of Fiji, Tonga and western Samoa for example, high concentrations of migrants that have moved from outer islands inhabit low and unsafe areas along the coasts.

Atoll nations, which include countries that are composed entirely of the smallest form of islands, called motus, are at risk of entire population displacement. These nations include Kiribati, Maldives, the Marshall Islands, Tokelau, and Tuvalu. According to a study on climate dangers to atoll countries, characteristics of atoll islands that make them vulnerable to sea level rise and other climate change impacts include their small size, their isolation from other land, their low income resources, and their lack of protective infrastructure.

A study that engaged the experiences of residents in atoll communities found that the cultural identities of these populations are strongly tied to these lands. The risk of losing these lands therefore threatens the national sovereignty, or right to self-determination, of Atoll nations. Human rights activists argue that the potential loss of entire atoll countries, and consequently the loss of cultures and indigenous lifeways cannot be compensated with financial means. Some researchers suggest that the focus of international dialogues on these issues should shift from ways to relocate entire communities to strategies that instead allow for these communities to remain on their lands.

Especially affected regions

The Arctic, Africa, small islands and Asian megadeltas are regions that are likely to be especially affected by future climate change.

Within other areas, some people are particularly at risk from future climate change, such as the poor, young children and the elderly.

The Arctic

The Arctic is likely to be especially affected by climate change because of the high projected rate of regional warming and associated impacts. Temperature projections for the Arctic region were assessed by Anisimov et al. (2007). These suggested areally averaged warming of about 2 °C to 9 °C by the year 2100. The range reflects different projections made by different climate models, run with different forcing scenarios. Radiative forcing is a measure of the effect of natural and human activities on the climate. Different forcing scenarios reflect, for example, different projections of future human greenhouse gas emissions.

Africa

Africa is likely to be the continent most vulnerable to climate change. With high confidence, Boko et al. (2007) projected that in many African countries and regions, agricultural production and food security would probably be severely compromised by climate change and climate variability.

The United Nations Environment Programme (UNEP, 2007) produced a post-conflict environmental assessment of Sudan. According to UNEP (2007), environmental stresses in Sudan are interlinked with other social, economic and political issues, such as population displacement and competition over natural resources. Regional climate change, through decreased precipitation, was thought to have been one of the factors which contributed to the conflict in Darfur. Along with other environmental issues, climate change could negatively affect future development in Sudan. One of the recommendations made by UNEP (2007) was for the international community to assist Sudan in adapting to climate change.

Located in the Greater Horn of Africa region, Kenya also experiences high vulnerability to the impacts of climate change. The main climate hazards include droughts and floods with current projects forecasting more intense and less predictable rainfall. In addition, other projections anticipate temperatures rising by 0.5 to 2 °C. In crowded, urban settlements in Nairobi, Kenya, the conditions of informal settlements or “slums” may exacerbate the impacts of climate change and disaster-related risk. In particular, the living conditions of large informal settlements often create a warmer "micro-climate" due to home construction materials, lack of ventilation, sparse green space, and poor access to electrical power and other services. To mitigate climate change-related risks in these informal neighborhood settlements, it will be important to upgrade these settlements through urban development interventions that are built for climate resilience. Such interventions include upgrades for waste.

Small and large islands

Small islands are especially vulnerable to the effects of climate change. Harsh and extreme weather conditions is a part of everyday life however as the climate changes these small islands find it difficult to adapt to the rising scale and intensity of storm surges, salt water intrusion and coastal destruction.

The Caribbean

Map of the Caribbean

 

Climate change in the Caribbean poses major risks to the islands in the Caribbean. The main environmental changes expected to affect the Caribbean are a rise in sea level, stronger hurricanes, longer dry seasons and shorter wet seasons. As a result, climate change is expected to lead to changes in the economy, environment and population of the Caribbean. Temperature rise of 2°C above preindustrial levels can increase the likelihood of extreme hurricane rainfall by four to five times in the Bahamas and three times in Cuba and Dominican Republic. Rise in sea level could impact coastal communities of the Caribbean if they are less than 3 metres (10 ft) above the sea. In Latin America and the Caribbean, it is expected that 29 – 32 million people may be affected by the sea level rise because they live below this threshold. The Bahamas and Trinidad and Tobago are expected to be the most affected because at least 80% of the total land is below the sea level.

The Philippines

According to the UN Office for the Coordination of Humanitarian Affairs (OCHA), the Philippines is one of the most disaster-prone countries in the world. The archipelago of 7,109 islands is situated along the Pacific Ocean's typhoon belt, leaving the country vulnerable to an average of 20 typhoons every year, five of which are destructive. In addition, the Philippines is also located within the “Pacific Ring of Fire" which makes the country prone to frequent earthquakes and volcanic eruptions. Compounding these issues, the impacts of climate change, such as accelerated sea level rise, exacerbate the state's high susceptibility to natural disasters, which also flooding and landslides.

Recognizing the Philippines’ considerable disaster risk, there is considerable need for disaster risk reduction and preparedness as well as humanitarian relief efforts. The Philippines institutionalizes the humanitarian cluster approach, and it plans and administers disaster relief through its National Disaster Risk Reduction and Management Council (NDRRMC). NDRRMC also oversees the 18 regional Disaster Risk Reduction Management Councils (LDRRMCs), which in turn supervise disaster risk reduction and management operations at the provincial, city, and barangay levels (barangay is the lowest level of government, similar to the "village" level.

Middle East

The region of Middle East is one of the most vulnerable to climate change. The impacts include increase in drought conditions, aridity, heatwaves, sea level rise. If greenhouse gas emissions are not reduced, the region can become uninhabitable before the year 2100.

South Asia

Afghanistan

Climate change impacts in Afghanistan culminate from overlapping interactions of natural disasters (due to changes in the climate system), conflict, agricultural dependency, and severe socio-economic hardship. Combined with infrequent earthquakes, climate-related disasters such as floods, flash floods, avalanches and heavy snowfalls on average affect 200,000 people every year, causing massive losses of lives, livelihoods and properties. Unfortunately, these interacting factors, particularly protracted conflicts which erode and challenge the ability to handle, adapt to and plan for climate change at individual and national levels, often turn climate change risks and hazards into disasters.

Ice-cover changes

Permanent ice cover on land is a result of a combination of low peak temperatures and sufficient precipitation. Some of the coldest places on Earth, such as the dry valleys of Antarctica, lack significant ice or snow coverage due to a lack of snow. Sea ice however maybe formed simply by low temperature, although precipitation may influence its stability by changing albedo, providing an insulating covering of snow and affecting heat transfer. Global warming has the capacity to alter both precipitation and temperature, resulting in significant changes to ice cover. Furthermore, the behaviour of ice sheets, ice caps and glaciers is altered by changes in temperature and precipitation, particularly as regards the behaviour of water flowing into and through the ice.

Arctic sea ice

Arctic sea ice minima in 2005, 2007, and the 1979-2000 average.

Recent projections of sea ice loss suggest that the Arctic ocean will likely be free of summer sea ice sometime between 2059 and 2078.

Models showing decreasing sea ice also show a corresponding decrease in polar bear habitat. Some scientists see the polar bear as a species which will be affected first and most severely by global warming because it is a top-level predator in the Arctic, which is projected to warm more than the global average. Recent reports show polar bears resorting to cannibalism, and scientists state that these are the only instances that they have observed of polar bears stalking and killing one another for food.

Antarctica

The collapse of Larsen B, showing the diminishing extent of the shelf from 1998 to 2002

The Antarctic peninsula has lost a number of ice shelves recently. These are large areas of floating ice which are fed by glaciers. Many are the size of a small country. The sudden collapse of the Larsen B ice shelf in 2002 took 5 weeks or less and may have been due to global warming. Larsen B had previously been stable for up to 12,000 years.

Concern has been expressed about the stability of the West Antarctic ice sheet. A collapse of the West Antarctic ice sheet could occur "within 300 years [as] a worst-case scenario. Rapid sea-level rise (>1 m per century) is more likely to come from the WAIS than from the [Greenland ice sheet]."

Greenland

As the Greenland ice sheet loses mass from calving of icebergs as well as by melting of ice, any such processes tend to accelerate the loss of the ice sheet.

The IPCC suggest that Greenland will become ice free at around 5 Celsius degrees over pre-industrial levels, but subsequent research comparing data from the Eemian period suggests that the ice sheet will remain at least in part at these temperatures. The volume of ice in the Greenland sheet is sufficient to cause a global sea level rise of 7 meters. It would take 3,000 years to completely melt the Greenland ice sheet. This figure was derived from the assumed levels of greenhouse gases over the duration of the experiment. In reality, these greenhouse gas levels are of course affected by future emissions and may differ from the assumptions made in the model.

Glaciers

Glacier retreat does not only affect the communities and ecosystems around the actual glacier but the entire downstream region. The most notable example of this is in India, where river systems such as the Indus and Ganges are ultimately fed by glacial meltwater from the Himalayas. Loss of these glaciers will have dramatic effects on the downstream region, increasing the risk of drought as lower flows of meltwater reduce summer river flows unless summer precipitation increases. Altered patterns of flooding can also affect soil fertility.

The Tibetan Plateau contains the world's third-largest store of ice. Qin Dahe, the former head of the China Meteorological Administration, said that the recent fast pace of melting and warmer temperatures will be good for agriculture and tourism in the short term; but issued a strong warning:

"Temperatures are rising four times faster than elsewhere in China, and the Tibetan glaciers are retreating at a higher speed than in any other part of the world.... In the short term, this will cause lakes to expand and bring floods and mudflows.... In the long run, the glaciers are vital lifelines for Asian rivers, including the Indus and the Ganges. Once they vanish, water supplies in those regions will be in peril."

Permafrost regions

Regions of permafrost cover much of the Arctic. In many areas, permafrost is melting, leading to the formation of a boggy, undulating landscape filled with thermokarst lakes and distinctive patterns of drunken trees. The process of permafrost melting is complex and poorly understood since existing models do not include feedback effects such as the heat generated by decomposition.

Arctic permafrost soils are estimated to store twice as much carbon as is currently present in the atmosphere in the form of CO2. Warming in the Arctic is causing increased emissions of CO2 and Methane (CH₄).

Precipitation and vegetation changes

The Eastern Amazon rainforest may be replaced by Caatinga vegetation as a result of global warming.

Much of the effect of global warming is felt through its influence on rain and snow. Regions may become wetter, drier, or may experience changes in the intensity of precipitation - such as moving from a damp climate to one defined by a mixture of floods and droughts. These changes may have a very severe impact on both the natural world and human civilisation, as both naturally occurring and farmed plants experience regional climate change that is beyond their ability to tolerate.

A U.S. National Oceanic and Atmospheric Administration (NOAA) analysis published in the Journal of Climate October 2011, and cited on Joseph J. Romm's, climateprogress.org, found that increasing droughts in the Middle East during the wintertime when the region traditionally receives most of its rainfall to replenish aquifers, and anthropogenic climate change is partly responsible. Per Earth System Research Laboratory's Martin Hoerling “The magnitude and frequency of the drying that has occurred is too great to be explained by natural variability alone,” and “This is not encouraging news for a region that already experiences water stress, because it implies natural variability alone is unlikely to return the region’s climate to normal.” the lead author of the paper. Twelve of the world's fifteen most water-scarce countries — Bahrain, Qatar, Algeria, Libya, Tunisia, Jordan, Saudi Arabia, Yemen, Oman, the United Arab Emirates, Kuwait, Israel and Palestine — are in the Middle East.

Arctic and Alpine regions

Polar and alpine ecosystems are assumed to be particularly vulnerable to climate change as their organisms dwell at temperatures just above the zero degree threshold for a very short summer growing season. Predicted changes in climate over the next 100 years are expected to be substantial in arctic and sub-arctic regions. Already there is evidence of upward shifts of plants in mountains and in arctic shrubs are predicted to increase substantially to warming.

Amazon

One modeling study suggested that the extent of the Amazon rainforest may be reduced by 70% if global warming continues unchecked, due to regional precipitation changes that result from weakening of large-scale tropical circulation.

North America

By the year 2100, severe storms that used to happen on average once every 20, 50, or 100 years ("twenty-year," "fifty-year," and "hundred-year storms") may happen every couple of years, according to a study published in June 2020 in Proceedings of the National Academy of Sciences.

Sahara

Some studies suggest that the Sahara desert may have been more vegetated during the warmer Mid-Holocene period, and that future warming may result in similar patterns.

Sahel

Some studies have found a greening of the Sahel due to global warming. Other climate models predict "a doubling of the number of anomalously dry years [in the Sahel] by the end of the century".

Desert expansion

Expansion of subtropical deserts is expected as a result of global warming, due to expansion of the Hadley Cell.

Coastal regions

Past sea-level changes and relative temperatures. Global warming is expected to dramatically affect sea level.

Global sea level is currently rising due to the thermal expansion of water in the oceans and the addition of water from ice sheets. Because of this, there low-lying coastal areas, many of which are heavily populated, are at risk of flooding.

Areas threatened by current sea level rise include Tuvalu and the Maldives. Regions that are prone to storm surges, such as London, are also threatened.

With very high confidence, IPCC (2007) projected that by the 2080s, many millions more people would experience floods every year due to sea level rise. The numbers affected were projected to be largest in the densely populated and low-lying megadeltas of Asia and Africa. Small islands were judged to be especially vulnerable.

Ocean effects

North Atlantic region

It has been suggested that a shutdown of the Atlantic thermohaline circulation may result in relative cooling of the North Atlantic region by up to 8C in certain locations. Recent research suggests that this process is not currently underway.

Tropical surface and troposphere temperatures

In the tropics, basic physical considerations, climate models, and multiple independent data sets indicate that the warming trend due to well-mixed greenhouse gases should be faster in the troposphere than at the surface.