Scientists found that the cooling coincided with a large-scale volcanic event - called the North Sea Dome – which restricted the flow of ocean water and the associated heat that it carried from the equator towards the North Pole region.

The team suggests that it is this volcanic event, preventing the ocean flow, rather than a change in carbon dioxide (CO2) in the atmosphere (which causes today's climate change), that led to an extended Ice age in a period more synonymous with very warm conditions.

"We tend to think of the Jurassic as a warm 'greenhouse' world where high temperatures were governed by high atmospheric carbon dioxide contents," said Stephen Hesselbo, professor at Camborne School of Mines in UK.

"This new study suggests that re-organisation of oceanic current patterns may also have triggered large scale climate changes," said Hesselbo. Rather than the seven continents that cover Earth's surface today, during the Jurassic Period there was one single 'supercontinent', called Pangaea. This supercontinent had a broad seaway across it that connected a north polar sea to a warm equatorial ocean, called Tethys.

The study was published in the journal Nature Communications.