Impact winter
Encyclopedia
An impact winter is a period of prolonged cold weather caused by the impact on the Earth of a large asteroid
or comet
. If such an impact occurred on land or the floor of a shallow sea, it could cause large amounts of dust or ash to be thrown into the Earth's atmosphere, blocking the Sun's light and dramatically lowering the amount of sunlight reaching the Earth's surface. Impact winter is one of the mechanisms proposed for extinction event
s, such as the asteroid impact at Chicxulub
in Mexico
which supposedly led to the extinction of the dinosaurs
.
Depending on the size of the object, and the location and angle at which it hits the earth, material can be thrown into the atmosphere by two mechanisms:
The latter scenario is the more dangerous, as the lighter particles from the fire would take weeks or months to fall back to earth, and could be distributed by jet stream
s around the world, making the cooling a global event.
The mechanism of impact winter is very similar to that which occurs after nuclear war
, leading to nuclear winter
. Volcanoes also eject large amounts of opaque material into the higher parts of the atmosphere, with large explosions such as the 1991 explosion of Mount Pinatubo
and the much larger 1783 Laki
eruption, having measurable effects on the world's climate. The simultaneous eruption of a number of large volcanoes, a catastrophic volcanic winter
scenario, is another proposed mechanism for extinction events.
novel
s and short stories.
In the episode "Impact Winter
" of the popular television show The West Wing
, NASA
sights a large asteroid that could possibly collide with Earth. President Bartlet recounts the worst case scenario, saying "If the asteroid hits [the forests of Russia], a shower of burning rock rains down on those woods and starts a fire that burns, that shrouds the hemisphere in a blanket of soot and ash that blocks out the sun for weeks. 'Impact Winter', they call it."
The Doctor Who
audio drama
Blood of the Daleks
is set on a human colony world which has suffered an asteroid strike and is undergoing an impact winter.
In Chrono Trigger
, the impact of Lavos in 65,000,000 B.C. caused an impact winter that apparently lasted for millions of years.
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...
or comet
Comet
A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...
. If such an impact occurred on land or the floor of a shallow sea, it could cause large amounts of dust or ash to be thrown into the Earth's atmosphere, blocking the Sun's light and dramatically lowering the amount of sunlight reaching the Earth's surface. Impact winter is one of the mechanisms proposed for extinction event
Extinction event
An extinction event is a sharp decrease in the diversity and abundance of macroscopic life. They occur when the rate of extinction increases with respect to the rate of speciation...
s, such as the asteroid impact at Chicxulub
Chicxulub Crater
The Chicxulub crater is an ancient impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is located near the town of Chicxulub, after which the crater is named...
in Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
which supposedly led to the extinction of the dinosaurs
Cretaceous-Tertiary extinction event
The Cretaceous–Paleogene extinction event, formerly named and still commonly referred to as the Cretaceous-Tertiary extinction event, occurred approximately 65.5 million years ago at the end of the Maastrichtian age of the Cretaceous period. It was a large-scale mass extinction of animal and plant...
.
Depending on the size of the object, and the location and angle at which it hits the earth, material can be thrown into the atmosphere by two mechanisms:
- The impact could eject large amounts of regolithRegolithRegolith is a layer of loose, heterogeneous material covering solid rock. It includes dust, soil, broken rock, and other related materials and is present on Earth, the Moon, some asteroids, and other terrestrial planets and moons.-Etymology:...
(and perhaps shattered bedrockBedrockIn stratigraphy, bedrock is the native consolidated rock underlying the surface of a terrestrial planet, usually the Earth. Above the bedrock is usually an area of broken and weathered unconsolidated rock in the basal subsoil...
) into the atmosphere - The impact could produce a global firestorm or strike a heavily forested area, throwing up large amounts of smoke and ash into the atmosphere.
The latter scenario is the more dangerous, as the lighter particles from the fire would take weeks or months to fall back to earth, and could be distributed by jet stream
Jet stream
Jet streams are fast flowing, narrow air currents found in the atmospheres of some planets, including Earth. The main jet streams are located near the tropopause, the transition between the troposphere and the stratosphere . The major jet streams on Earth are westerly winds...
s around the world, making the cooling a global event.
The mechanism of impact winter is very similar to that which occurs after nuclear war
Nuclear warfare
Nuclear warfare, or atomic warfare, is a military conflict or political strategy in which nuclear weaponry is detonated on an opponent. Compared to conventional warfare, nuclear warfare can be vastly more destructive in range and extent of damage...
, leading to nuclear winter
Nuclear winter
Nuclear winter is a predicted climatic effect of nuclear war. It has been theorized that severely cold weather and reduced sunlight for a period of months or even years could be caused by detonating large numbers of nuclear weapons, especially over flammable targets such as cities, where large...
. Volcanoes also eject large amounts of opaque material into the higher parts of the atmosphere, with large explosions such as the 1991 explosion of Mount Pinatubo
Mount Pinatubo
Mount Pinatubo is an active stratovolcano located on the island of Luzon, near the tripoint of the Philippine provinces of Zambales, Tarlac, and Pampanga. It is located in the Tri-Cabusilan Mountain range separating the west coast of Luzon from the central plains, and is west of the dormant and...
and the much larger 1783 Laki
Laki
Łąki may refer to the following places in Poland:*Łąki, Lower Silesian Voivodeship *Łąki, West Pomeranian Voivodeship *Łąki, Lublin Voivodeship...
eruption, having measurable effects on the world's climate. The simultaneous eruption of a number of large volcanoes, a catastrophic volcanic winter
Volcanic winter
A volcanic winter is the reduction in temperature caused by volcanic ash and droplets of sulfuric acid obscuring the sun and raising Earth's albedo after a large particularly explosive type of volcanic eruption...
scenario, is another proposed mechanism for extinction events.
Impact winters in popular culture
Impact winter (along with nuclear and volcanic winters) are often the subject of science fictionScience fiction
Science fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...
novel
Novel
A novel is a book of long narrative in literary prose. The genre has historical roots both in the fields of the medieval and early modern romance and in the tradition of the novella. The latter supplied the present generic term in the late 18th century....
s and short stories.
In the episode "Impact Winter
Impact Winter (The West Wing)
-Plot:In China, an impaired President Bartlet is having trouble sitting through meetings following his MS attack, but pushes through on his plans to meet individually with the Chinese Premier about North Korea--a step that produces an extraordinary agreement for a regional conference on the North's...
" of the popular television show The West Wing
The West Wing (TV series)
The West Wing is an American television serial drama created by Aaron Sorkin that was originally broadcast on NBC from September 22, 1999 to May 14, 2006...
, NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
sights a large asteroid that could possibly collide with Earth. President Bartlet recounts the worst case scenario, saying "If the asteroid hits [the forests of Russia], a shower of burning rock rains down on those woods and starts a fire that burns, that shrouds the hemisphere in a blanket of soot and ash that blocks out the sun for weeks. 'Impact Winter', they call it."
The Doctor Who
Doctor Who
Doctor Who is a British science fiction television programme produced by the BBC. The programme depicts the adventures of a time-travelling humanoid alien known as the Doctor who explores the universe in a sentient time machine called the TARDIS that flies through time and space, whose exterior...
audio drama
Radio drama
Radio drama is a dramatized, purely acoustic performance, broadcast on radio or published on audio media, such as tape or CD. With no visual component, radio drama depends on dialogue, music and sound effects to help the listener imagine the characters and story...
Blood of the Daleks
Blood of the Daleks
Blood of the Daleks is an audio drama based on the long-running British science fiction television series Doctor Who. This audio drama was produced by Big Finish Productions; the first of two 50-minute parts was broadcast on BBC 7 on 31 December 2006, and the second was aired on 7 January 2007...
is set on a human colony world which has suffered an asteroid strike and is undergoing an impact winter.
In Chrono Trigger
Chrono Trigger
is a role-playing video game developed and published by Square for the Super Nintendo Entertainment System in 1995. Chrono Triggers development team included three designers that Square dubbed the "Dream Team": Hironobu Sakaguchi, the creator of Square's Final Fantasy series; Yuji Horii, a...
, the impact of Lavos in 65,000,000 B.C. caused an impact winter that apparently lasted for millions of years.