Volcanic event responsible for Jurassic Period ice age
8 Jan 2016 by qwqcdhhcbc.d qwqcdhhcbc.d
Scientists have uncovered the reason behind an ice age that took place around 170 million years ago – a large-scale volcanic event.
Scientists have uncovered the reason behind an ice age that took place around 170 million years ago – a large-scale volcanic event.
The North Sea Dome is believed to have restricted the flow of ocean water from the equator to the North Pole. Researchers suggest it was this event, instead of a change of CO2 – responsible for climate change currently – that lead to the extended Ice Age.
Professor Stephen Hesselbo, from the Camborn School of Mines, said: “We tend to think of the Jurassic as a warm 'greenhouse' world where high temperatures were governed by high atmospheric carbon dioxide contents. This new study suggests that re-organization of oceanic current patterns may also have triggered large scale climate changes.”
During the Jurassic Period, a single ‘supercontinent’ called Pangea existed. A broad sea, Tethys, connected the north polar sea to a equatorial ocean.
After a decade of constructing temperature changes using fossilised mollusc shells, the tea were able to identify and link the North Sea Dome event to the Earth undergoing a significant and fast cooling in temperature.
It is believed the cold period last millions of years until the North Sea Dome subsided.
Professor Hesselbo added: "Although we have known about the occurrence of cold periods during greenhouse times for a while, their origins have remained mysterious. This work suggests a mechanism at play that may also have been important for driving other climate change events in the Jurassic and at other times in Earth history."
The research was published in Nature Communications.
