Active Volcano

there no consensus among volcanologists on how define active volcano. lifespan of volcano can vary months several million years, making such distinction meaningless when compared lifespans of humans or civilizations. example, many of earth s volcanoes have erupted dozens of times in past few thousand years not showing signs of eruption. given long lifespan of such volcanoes, active. human lifespans, however, not.

scientists consider volcano erupting or erupt if erupting, or showing signs of unrest such unusual earthquake activity or significant new gas emissions. scientists consider volcano active if has erupted in last 10,000 years (holocene times) – smithsonian global volcanism program uses definition of active. volcanoes situated on pacific ring of fire. estimated 500 million people live near active volcanoes.

historical time (or recorded history) timeframe active. catalogue of active volcanoes of world, published international association of volcanology, uses definition, there more 500 active volcanoes. however, span of recorded history differs region region. in china , mediterranean, reaches 3,000 years, in pacific northwest of united states , canada, reaches less 300 years, , in hawaii , new zealand, around 200 years.

kīlauea lava entering sea.



lava flows @ holuhraun, iceland, september 2014

as of 2013, following considered earth s active volcanoes:

kīlauea, famous hawaiian volcano, has been in continuous, effusive eruption (in lava steadily flows onto ground) since 1983 , has longest-observed lava lake.
mount etna , nearby stromboli, 2 mediterranean volcanoes in continuous eruption since antiquity.
mount yasur, in vanuatu, has been erupting continuously on 800 years.

as of august 2013, longest ongoing (but not continuous) volcanic eruptive phases are:

mount yasur, 111 years
mount etna, 109 years
stromboli, 108 years
santa maría, 101 years
sangay, 94 years

other active volcanoes include:

mount nyiragongo , neighbor, nyamuragira, africa s active volcanoes

nyiragongo s lava lake


.
piton de la fournaise, in réunion, erupts enough tourist attraction.
erta ale, in afar triangle, has maintained lava lake since @ least 1906.
mount erebus, in antarctica, has maintained lava lake since @ least 1972.
mount merapi
whakaari / white island, has been in continuous state of smoking since discovery in 1769.
ol doinyo lengai
ambrym
arenal volcano
pacaya
klyuchevskaya sopka
sheveluch




^ volcanoes . european space agency. 2009. retrieved august 16, 2012. 
^ decker, robert wayne; decker, barbara (1991). mountains of fire: nature of volcanoes. cambridge university press. p. 7. isbn 0-521-31290-6. retrieved august 16, 2012. 
^ tilling, robert i. (1997). volcano environments . volcanoes. denver, colorado: u.s. department of interior, u.s. geological survey. retrieved august 16, 2012. there more 500 active volcanoes (those have erupted @ least once within recorded history) in world 
^ active volcanoes in world . volcanodiscovery.com. retrieved 3 august 2013. 
^ world s 5 active volcanoes . livescience.com. retrieved 4 august 2013.