The melting of Antarctic icebergs could be the key to the activation of a series of mechanisms that cause the Earth to suffer prolonged periods of cooling according to Francisco J. Jiménez-Espejo, a researcher at the Andalusian Earth Sciences Institute (CSIC-UGR).
It has long been believed that changes in the Earth’s orbit, as it moves around the sun, trigger the beginning or end of glacial periods by affecting the amount of solar radiation that reaches the planet’s surface. However, until now, the question of how small variations in the solar energy that reaches the Earth can lead to such dramatic shifts in the planet’s climate has been a mystery.
In this new study, a multinational group of researchers proposes that, when the Earth’s orbit around the sun is just right, the Antarctic icebergs begin to melt further and further away from the continent, moving massive volumes of freshwater from the Antarctic Ocean into the Atlantic.
This process causes the Antarctic Ocean to become increasingly salty, while the Atlantic Ocean becomes fresher, affecting overall ocean circulation patterns, drawing CO2 from the atmosphere and reducing the greenhouse effect. These mark the initial stages at the beginning of an ice age on the planet.
University of Granada. (2021, February 19). The melting of large icebergs is a key stage in the evolution of ice ages. ScienceDaily. https://www.sciencedaily.com/releases/2021/02/210219155906.htm