Query: Volcanoes Melting West Antarctic Glaciers, Not Global Warming

Relevant passages:
Snowball Earth <=SEP=> The Snowball Earth hypothesis proposes that Earth 's surface became entirely or nearly entirely frozen at least once , sometime earlier than 650 Mya ( million years ago ) . Proponents of the hypothesis argue that it best explains sedimentary deposits generally regarded as of glacial origin at tropical palaeolatitudes , and other enigmatic features in the geological record . Opponents of the hypothesis contest the implications of the geological evidence for global glaciation and the geophysical feasibility of an ice - or slush-covered ocean , and emphasize the difficulty of escaping an all-frozen condition . A number of unanswered questions remain , including whether the Earth was a full snowball , or a `` slushball '' with a thin equatorial band of open ( or seasonally open ) water .   The snowball Earth episodes occurred before the sudden radiation of multicellular bioforms , known as the Cambrian explosion . The most recent snowball episode may have triggered the evolution of multicellularity . Another , much earlier and longer snowball episode , the Huronian glaciation , which occurred 2400 to 2100 Mya , may have been triggered by the first appearance of oxygen in the atmosphere , the `` Great Oxygenation Event . ''

Climate variability <=SEP=> Climate variability includes all the variations in the climate that last longer than individual weather events, whereas the term climate change only refers to those variations that persist for a longer period of time, typically decades or more. In the time since the industrial revolution the climate has increasingly been affected by human activities that are causing global warming and climate change.The climate system receives nearly all of its energy from the sun. The climate system also radiates energy to outer space. The balance of incoming and outgoing energy, and the passage of the energy through the climate system, determines Earth's energy budget. When the incoming energy is greater than the outgoing energy, earth's energy budget is positive and the climate system is warming. If more energy goes out, the energy budget is negative and earth experiences cooling. The energy moving through Earth's climate system finds expression in weather, varying on geographic scales and time. Long-term averages and variability of weather in a region constitute the region's climate. Such changes can be the result of "internal variability", when natural processes inherent to the various parts of the climate system alter the distribution of energy. Examples include variability in ocean basins such as the Pacific decadal oscillation and Atlantic multidecadal oscillation. Climate variability can also result from external forcing, when events outside of the climate system's components nonetheless produce changes within the system. Examples include changes in solar output and volcanism. Climate variability has consequences for sea level changes, plant life, and mass extinctions; it also affects human societies.

Parinacota (volcano) <=SEP=> Parinacota ( in Hispanicized spelling ) , Parina Quta or Parinaquta is a dormant stratovolcano on the border of Chile and Bolivia . Together with Pomerape it forms the Nevados de Payachata volcanic chain . Part of the Central Volcanic Zone of the Andes , its summit reaches an elevation of 6380 m above sea level . The symmetrical cone is capped off by a summit crater with widths of 1 km or 500 m. Farther down on the southern slopes lie three parasitic centres known as the Ajata cones . These cones have generated lava flows . The volcano overlies a platform formed by lava domes and andesitic lava flows .   The volcano started growing during the Pleistocene and formed a large cone . At some point between the Pleistocene and the Holocene , the western flank of the volcano collapsed , generating a giant landslide that spread west and formed a large , hummocky landslide deposit . The avalanche crossed and dammed a previously existing drainage , impounding or enlarging Lake Chungará ; numerous other lakes now forming the headwaters of the Rio Lauca sprung up within the deposit . Volcanic activity rebuilt the cone after the collapse , cancelling out the collapse scar .   Parinacota had numerous effusive and explosive eruptions during the Holocene , the latest about 200 years ago . While there are no recorded eruptions , legends of the local Aymara people imply that they may have witnessed one eruption .   Renewed activity at Parinacota is possible in the future , although the relatively low population density in the region acts to limit the amount of damage that could occur . Some towns and a regional highway between Bolivia and Chile are potentially exposed to the effects of a new eruption .

Antarctica <=SEP=> Antarctica ( UK English -LSB- ænˈtɑːktɪkə -RSB- or -LSB- ænˈtɑːtɪkə -RSB- , US English -LSB- æntˈɑːrktɪkə -RSB- ) is Earth 's southernmost continent . It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere , almost entirely south of the Antarctic Circle , and is surrounded by the Southern Ocean . At 14000000 km2 , it is the fifth-largest continent . For comparison , Antarctica is nearly twice the size of Australia . About 98 % of Antarctica is covered by ice that averages 1.9 km in thickness , which extends to all but the northernmost reaches of the Antarctic Peninsula .   Antarctica , on average , is the coldest , driest , and windiest continent , and has the highest average elevation of all the continents . Antarctica is a desert , with annual precipitation of only 200 mm ( 8 in ) along the coast and far less inland . The temperature in Antarctica has reached − 89.2 ° C ( − 128.6 ° F ) , though the average for the third quarter ( the coldest part of the year ) is − 63 ° C ( − 81 ° F ) . Anywhere from 1,000 to 5,000 people reside throughout the year at the research stations scattered across the continent . Organisms native to Antarctica include many types of algae , bacteria , fungi , plants , protista , and certain animals , such as mites , nematodes , penguins , seals and tardigrades . Vegetation , where it occurs , is tundra .   Although myths and speculation about a Terra Australis ( `` Southern Land '' ) date back to antiquity , Antarctica is noted as the last region on Earth in recorded history to be discovered and colonised by humans , being only first sighted in 1820 by the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny , who sighted the Fimbul ice shelf . The continent , however , remained largely neglected for the rest of the 19th century because of its hostile environment , lack of easily accessible resources , and isolation . In 1895 , the first confirmed landing was conducted by a team of Norwegians .   Antarctica is a de facto condominium , governed by parties to the Antarctic Treaty System that have consulting status . Twelve countries signed the Antarctic Treaty in 1959 , and thirty-eight have signed it since then . The treaty prohibits military activities and mineral mining , prohibits nuclear explosions and nuclear waste disposal , supports scientific research , and protects the continent 's ecozone . Ongoing experiments are conducted by more than 4,000 scientists from many nations .