Pico de Orizaba, also known as Citlaltépetl (from
Nahuatl = star, and = mountain), is an inactive
stratovolcano, the highest
mountain
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually highe ...
in
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
and the
third highest in
North America, after
Denali of
Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...
in the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...
and
Mount Logan of
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
. Pico de Orizaba is also the highest volcanic summit in North America. It rises above sea level in the eastern end of the
Trans-Mexican Volcanic Belt
The Trans-Mexican Volcanic Belt ( es, Eje Volcánico Transversal), also known as the Transvolcanic Belt and locally as the (''Snowy Mountain Range''), is an active volcanic belt that covers central-southern Mexico. Several of its highest peaks h ...
, on the border between the states of
Veracruz
Veracruz (), formally Veracruz de Ignacio de la Llave (), officially the Free and Sovereign State of Veracruz de Ignacio de la Llave ( es, Estado Libre y Soberano de Veracruz de Ignacio de la Llave), is one of the 31 states which, along with Me ...
and
Puebla.
The volcano is currently
dormant but not
extinct, with the last eruption taking place during the 19th century. It is the second most
prominent volcanic peak in the world after Africa's
Mount Kilimanjaro.
Toponymy
Pico de Orizaba overlooks the valley and city of
Orizaba, from which it gets its Spanish name. During the colonial era, the volcano was also known as Cerro de San Andrés due to the nearby settlement of San Andrés Chalchicomula at its base.
Its Náhuatl name, Citlaltépetl, comes from ''citlalli'' (star) and tepētl (mountain) and thus means "Star Mountain". This name is thought to be based on the fact that the snow-covered peak can be seen year round for hundreds of kilometers throughout the region. This name is not, however, used by Náhuatl speakers of the Orizaba area, who instead call it ''Istaktepetl'' (''Iztactépetl'' in the traditional orthography for
Classical Nahuatl), meaning 'White Mountain'.
A third name, Poyauhtecatl, which means "the one that colours or illuminates", has also been recorded. This name was given by the Tlaxcaltecs in memory of their lost country.
Topography
The peak of Citlaltépetl rises dramatically to an elevation of above sea level; it has a
topographic prominence
In topography, prominence (also referred to as autonomous height, relative height, and shoulder drop in US English, and drop or relative height in British English) measures the height of a mountain or hill's summit relative to the lowest contou ...
of . Regionally dominant, Pico de Orizaba is the highest peak in Mexico and the highest volcano in North America; it is also the third highest peak in North America after
Denali and
Mount Logan. Orizaba is ranked
7th in the world in
topographic prominence
In topography, prominence (also referred to as autonomous height, relative height, and shoulder drop in US English, and drop or relative height in British English) measures the height of a mountain or hill's summit relative to the lowest contou ...
. It is the second most prominent
volcanic peak in the world after Africa's
Mount Kilimanjaro, and the volcano is also ranked 16th in the world for
topographic isolation. About to the west of the port of
Veracruz
Veracruz (), formally Veracruz de Ignacio de la Llave (), officially the Free and Sovereign State of Veracruz de Ignacio de la Llave ( es, Estado Libre y Soberano de Veracruz de Ignacio de la Llave), is one of the 31 states which, along with Me ...
, its peak is visible to ships approaching the port in the
Gulf of Mexico
The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...
, and at dawn rays of sunlight strike the Pico while Veracruz still lies in shadow. The topography of Pico de Orizaba is
asymmetrical
Asymmetry is the absence of, or a violation of, symmetry (the property of an object being invariant to a transformation, such as reflection). Symmetry is an important property of both physical and abstract systems and it may be displayed in pre ...
from the center of the crater; the eastern face is the steepest side of the volcano and the northwestern face the most gradual side. The gradual slopes of the northwestern face of the volcano allows for the presence of large glaciers and is the most traveled route to take for hikers traveling to the summit.
Glaciers
Pico de Orizaba is one of only three volcanoes in México that continue to support glaciers and is home to the largest glacier in Mexico,
Gran Glaciar Norte. Orizaba has nine known glaciers: Gran Glaciar Norte, Lengua del Chichimeco, Jamapa, Toro, Glaciar de la Barba, Noroccidental, Occidental, Suroccidental, and Oriental. The
equilibrium line altitude (ELA) is not known for Orizaba. Snow on the south and southeast sides of the volcano melts quickly because of solar radiation, but lower temperatures on the northwest and north sides allow for glaciers. The insolation angle and wind redeposition on the northwest and north sides allow for constant accumulation of snow providing a source for the
outlet glaciers. On the north side of Orizaba, the Gran Glaciar Norte fills the elongated highland basin and is the source for seven outlet glaciers. The main glacier extends north of the crater rim, has a surface area of about descending from to about . It has a slightly irregular and stepped profile that is caused in part by the configuration of the bedrock. Most
crevasses show an ice thickness of approximately .
Below the in elevation on the north side of the volcano, the outlet glaciers Lengua del Chichimeco and Jamapa extend north and northwest another and , respectively. The terminal lobe of Lengua del Chichimeco at , having a gradient of only , is a low, broad ice fan that has a convex-upward profile, a front typical of almost all Mexican glaciers. The most distinct glacier is Glaciar de Jamapa, which leaves Gran Glaciar Norte at about and, after with a gradient of , divides into two small tongues that end at and . Both tongues terminate in broad convex-upward ice fans thinning along their edges. The retreat of these tongues prior to 1994 produced much erosion downstream and buried their edges by ablation rock debris.
The west side of Gran Glaciar Norte generates five outlet glaciers. From north to south, the first two, Glaciar del Toro and Glaciar de la Barba, are hanging cliff or icefall glaciers, reaching the tops of giant lava steps at and , respectively. They then descend farther down into the heads of stream valleys as huge ice blocks but are not regenerated there. About , Glaciar Noroccidental, a small outlet glacier long, drains away from the side of Gran Glaciar Norte at about and draws down the ice surface a few tens of meters over a distance of , descending to with a gradient of . Another still farther south, Glaciar Occidental breaks away from Gran Glaciar Norte west of the summit crater at about as a steep, long glacier having a gradient of that ends at . From the southwest corner of the mountain, another outlet glacier, Glaciar Suroccidental, long, flows from Gran Glaciar Norte at with a gradient of , which also ends at in a long smooth surface.
East of the summit cone, a separate steep niche glacier, Glaciar Oriental, long and having a gradient of , flows down the mountainside from about ; it contains many crevasses and seracs and is the most difficult glacier to climb. Glacier Oriental had a surface area of about in 1958, which makes the total area of glaciers and firn field on Citlaltépetl about . No earlier historical record of glacier tongue activity (advance or recession) is known for Citlaltépetl's glaciers. Although the Gran Glaciar Norte ice cap is covered with snow, it is possible to see the seven outlet glaciers on the irregular west margin of the ice cap, especially Glaciar de Jamapa and Glaciar Occidental.
Climate
The climate of Pico de Orizaba, like the
Sierra Madre Oriental, varies greatly due to the change of elevation and
prevailing winds
In meteorology, prevailing wind in a region of the Earth's surface is a surface wind that blows predominantly from a particular direction. The dominant winds are the trends in direction of wind with the highest speed over a particular point on ...
. Due to the latitude and the extreme rugged terrain the volcano experiences many
microclimates. Vegetation varies from tropical at the lower elevations on the eastern face to alpine forests in the higher elevations.
Large amounts of precipitation fall on the eastern face of the volcano due to
adiabatic cooling
In thermodynamics, an adiabatic process (Greek: ''adiábatos'', "impassable") is a type of thermodynamic process that occurs without transferring heat or mass between the thermodynamic system and its environment. Unlike an isothermal process, a ...
and condensation from the
trade winds
The trade winds or easterlies are the permanent east-to-west prevailing winds that flow in the Earth's equatorial region. The trade winds blow mainly from the northeast in the Northern Hemisphere and from the southeast in the Southern Hemisp ...
that bring moisture off the Gulf of Mexico. The eastern face is frequently covered by fog and low cloud cover. The climate of the eastern face varies from tropical
(Af) at the lower elevations to subtropical highland
(Cwb) at the higher elevations, with mild variation in temperatures and an average annual rainfall of .
Subtropical climates are found between above sea level with a regular rainfall all year long. Autumn and winter come with frequent freezes and light snow, but the snow on the south and southeast sides melt quickly due to solar radiation. The northern face is dominated by subtropical highland
(Cwb). The southern face mostly experiences a humid subtropical climate,
(Cwa) with the highest annual temperatures in the month of April.
Due to
katabatic wind
A katabatic wind (named from the Greek word κατάβασις ''katabasis'', meaning "descending") is a drainage wind, a wind that carries high-density air from a higher elevation down a slope under the force of gravity. Such winds are sometim ...
s the western side is dominated by steppe
(BSk) creating a rain shadow below above sea level. Although there are some areas on the western side that experience
(Cfa) most of the area is semi-dry with temperate to warm temperatures and an annual precipitation average of . Vegetation here is grass and shrubs with few alpine species.
Between where temperatures usually are between , continental subarctic climate
(Dfc) predominates. Over with an annual average low of ,
alpine tundra (ET) prevails to the summit; heavy snowfalls and blizzards are common throughout the year. Snow on the south and southeast melts due to solar radiation, but continually remains on the north and northwestern faces. Extreme cold dominates a surface area of approximately .
Geology
Pico de Orizaba evolved in three stages, the most recent initiated about 16,000 years ago during the late
Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...
and
Holocene
The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togeth ...
. Citlaltépetl consists of three superimposed stratovolcanoes and dome intrusions: Torrecillas (650–250
ka), Espolón de Oro (210– 16 ka), and Citlaltépetl (16 ka to present). The volcano was formed by thick
andesitic
Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predomin ...
and
dacitic
Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyol ...
lavas that followed repetitive explosive eruptions and
lava effusions that created the iconic cone structure. The volcano is currently
dormant but not
extinct. The latest eruption of the volcano occurred in 1846 with a magnitude of
VEI 2. Previous eruptions occurred in: 1687, 1613, 1589–1569, 1566, 1555–1545,1539–1533, 1351, 1260, 1187, 1175, 1157, 220 AD, 140 AD, 90 AD, 40 AD, ~780 BC, ~1500 BC, ~2110 BC, ~2300 BC, ~2500 BC, ~2780 BC, ~4690 BC, ~6220 BC, ~6710 BC, ~7030 BC, and ~7530 BC.
The most violent eruption in the volcano's history is thought to have occurred around 6710 BC reaching a magnitude of
VEI 5 characterized by
lava dome extrusion and
pyroclastic flow.
The volcano's crater is elliptical with a
transverse diameter measuring and a
conjugate diameter measuring . The crater has an estimated with a maximum depth of . Pico de Orizaba is constantly covered by an
ice cap consisting of several glaciers. An outlet glacier, known as Jamapa Glacier is located on the north-eastern side of the peak; it has been a powerful force in shaping the volcano. The Jamapa Glacier is responsible for a significant portion of the
geomorphologic evolution of the region surrounding the volcano.
Geography
Pico de Orizaba is located at 19°1′48″N 97°16′12″W, about west of the Gulf of Mexico and east of
Mexico City
Mexico City ( es, link=no, Ciudad de México, ; abbr.: CDMX; Nahuatl: ''Altepetl Mexico'') is the capital city, capital and primate city, largest city of Mexico, and the List of North American cities by population, most populous city in North Amer ...
, on the border between the states of Veracruz and Puebla. The volcano is approximately south of the
Tropic of Cancer
The Tropic of Cancer, which is also referred to as the Northern Tropic, is the most northerly circle of latitude on Earth at which the Sun can be directly overhead. This occurs on the June solstice, when the Northern Hemisphere is tilted tow ...
. Orizaba anchors the south-eastern end of the
Trans-Mexican Volcanic Belt
The Trans-Mexican Volcanic Belt ( es, Eje Volcánico Transversal), also known as the Transvolcanic Belt and locally as the (''Snowy Mountain Range''), is an active volcanic belt that covers central-southern Mexico. Several of its highest peaks h ...
, a volcanic chain that runs from west to east across Central Mexico. A companion peak lying about six km to the southwest of Pico de Orizaba is the
Sierra Negra, at . This subsidiary peak is significantly lower than its massive neighbour, but the road to the observatory on its summit is the highest road in North America.
Pico de Orizaba, as part of the
Sierra Madre Oriental, forms a barrier between the coastal plains of the Gulf of Mexico and the
Mexican Plateau
The Central Mexican Plateau, also known as the Mexican Altiplano ( es, Altiplanicie Mexicana), is a large arid-to-semiarid plateau that occupies much of northern and central Mexico. Averaging above sea level, it extends from the United States b ...
. The volcano blocks the moisture from the Gulf of Mexico from saturating central Mexico and influences the climates of both areas. Both the state of Veracruz and Puebla depend on Pico de Orizaba for supplying fresh water. The largest river originating on the volcano is the
Jamapa River.
History
Pico de Orizaba was important in pre-Hispanic cultures, such as those of the Nahuatl-speaking
Aztec
The Aztecs () were a Mesoamerican culture that flourished in central Mexico in the post-classic period from 1300 to 1521. The Aztec people included different ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl ...
s and the
Totonac
The Totonac are an indigenous people of Mexico who reside in the states of Veracruz, Puebla, and Hidalgo. They are one of the possible builders of the pre-Columbian city of El Tajín, and further maintained quarters in Teotihuacán (a city ...
s. The volcano is part of many native mythologies.
During the
Spanish Conquest
The Spanish Empire ( es, link=no, Imperio español), also known as the Hispanic Monarchy ( es, link=no, Monarquía Hispánica) or the Catholic Monarchy ( es, link=no, Monarquía Católica) was a colonial empire governed by Spain and its predece ...
of Mexico,
Hernán Cortés passed through the foothills of Pico de Orizaba; the volcano and the surrounding mountains made his journey to
Tenochtitlan
, ; es, Tenochtitlan also known as Mexico-Tenochtitlan, ; es, México-Tenochtitlan was a large Mexican in what is now the historic center of Mexico City. The exact date of the founding of the city is unclear. The date 13 March 1325 was ...
more difficult and delayed him for many days. During the 1600s, the Spanish Crown financed several roads to be built that would circumvent Citlaltépetl. One of the roads was routed south of the volcano through the cities of Orizaba and Fortín de las Flores, which became the main trade route between Mexico City and Veracruz on the Gulf Coast. A short road was later built by
Jesuits
, image = Ihs-logo.svg
, image_size = 175px
, caption = ChristogramOfficial seal of the Jesuits
, abbreviation = SJ
, nickname = Jesuits
, formation =
, founders = ...
to establish settlements at the base of Pico de Orizaba. The Spanish used the volcano as a landmark to guide themselves to the port of Veracruz. Many battles were fought near this volcano throughout Mexico's struggle for independence.
In 1839,
Henri Galeotti was the first European to explore the volcano, but did not hike to the summit. During the American occupation of Mexico in 1848, two American soldiers, F. Maynard and
William F. Raynolds, were the first known hikers to reach the summit of Pico de Orizaba.
In 1851, the French explorer Alejandro Doignon also reached the summit and found the flagpole left behind by the Americans in 1848. During the mid-19th century Citlaltépetl was explored by many scientists, including the
German botanist Hugo Fink, who was the first to record the numerous species of flora found on the volcano. In 1873,
Martin Tritschler raised the Mexican flag at the summit.
Pico de Orizaba National Park
On December 16, 1936, President
Lázaro Cárdenas, in an effort to protect the natural beauty of Pico de Orizaba, created a national park with an area of that included the volcano with the surrounding area and the settlements of Tlachichuca, Ciudad Serdán, La Perla, Mariano Escobedo, and Calcahualco. The federal decree became federal law on January 4, 1937.
Climbing and recreation
Pico de Orizaba attracts a large number of international climbers every year. There are multiple routes for approaching and climbing the volcano, and many people attempt it. Most people climb the mountain during the period from October to March when the weather is favorable; temperatures do not vary much month to month due to being in the tropics and April through September are rainy months in the region. The most frequented route begins from the base camp Piedra Grande Hut ("refugio") via the Jamapa Glacier, located at an elevation of above sea level.
Another option as a starting point is high camp located at the base of the glacier about above sea level. For a more technical challenge for the experienced climber, there is a technical ice climb called the Serpents Head, which involves 10 pitches of grade 3 ice. Additionally, the southern side offers another challenging option; although the trail is shorter, it is also steeper and more difficult. No glaciers are found on the southern side. The final ascent to the summit is via a normally straightforward and crevasse-free glacier route. The caldera can be circumnavigated with relative ease, although at one point this requires a short, exposed traverse of steep rock and ice above the Glacier Este.
See also
*
List of mountain peaks of North America
This article comprises three sortable tables of major mountain peaksThis article defines a significant summit as a summit with at least of topographic prominence, and a major summit as a summit with at least of topographic prominence. All ...
**
List of mountain peaks of Mexico
This article comprises three sortable tables of major mountain peaksThis article defines a significant summit as a summit with at least of topographic prominence, and a major summit as a summit with at least on topographic prominence. All sum ...
***
List of volcanoes in Mexico
***
List of Ultras of Mexico
The following sortable table comprises the 26 ultra-prominent summits of México. Each of these peaks has at least of topographic prominence.This article defines a significant summit as a summit with at least of topographic prominence, and ...
*
List of elevation extremes by country
The following sortable table lists land surface elevation extremes by country or dependent territory.
Topographic elevation is the vertical distance above the reference geoid, a mathematical model of the Earth's sea level as an equipotential gr ...
*
Orizaba
*
Volcanic Seven Summits
Footnotes
References
*
*
(in Spanish)
*
External links
Equipment List to climb Pico de OrizabaPico de Orizaba - ascent route description
{{DEFAULTSORT:Orizaba
Volcanoes of Veracruz
Pico de Orizaba
Pico de Orizaba
Pico de Orizaba
Pico de Orizaba
Stratovolcanoes of Mexico
Seven Third Summits
Volcanic Seven Summits
Pico de Orizaba
Pico de Orizaba
Religious places of the indigenous peoples of North America
VEI-5 volcanoes
National parks of Mexico
Protected areas of Veracruz
Protected areas of Puebla
Pleistocene stratovolcanoes
Holocene stratovolcanoes