RTVE.es/CSIC
million years ago, under conditions of high concentrations of carbon dioxide as current and temperatures slightly higher than those recorded in the present ocean, the oceans around Antarctica could not hold East Antarctic ice cap.
This emerges from a study conducted by a team led by the Higher Council for Scientific Research (CSIC) team has also found that there is direct relationship between changes in the Earth’s orbit and stability of this layer or floating ice floe.
“Emissions of greenhouse gases pose yet A energy intake much higher than that provided by changes in the Earth’s orbit “he noted CSIC researcher Carlota Escutia, the Andalusian Institute of Earth Sciences, who led the expedition .
The study shows that 2.5 million years ago, when carbon dioxide concentrations in the atmosphere were similar to today, the East Antarctic ice cap melting was widespread.
The research, which have involved 29 scientists from 12 countries, is published in the journal Nature Geosciences and has become demonstrated the phenomenon in the continental margin of Wilkes Land (East Antarctica), reported by the CSIC.
Generalized Meltdown
This work is based on the analysis of marine sediments were transported by icebergs makes between 2.2 and 4.3 million years , which have been collected during an expedition of the Integrated Ocean Drilling Program.
Sea levels may rise and fall hundreds of feet
Our results show that natural climatic processes can increase the response of the polar caps with relatively small energy changes resulting from changes in Earth’s orbit: can produce ups and downs of sea level tens of meters.
The sediment analysis shows that the stability of the Earth’s largest ice cap is influenced by the presence of ice floe in the oceans surrounding Antarctica.
The ice is sea water ice that forms a protective shield around the continent and the caps of Antarctica, and is susceptible to warming oceans generated as a result of increased greenhouse gases.
Lack of a ‘shield’
“The disappearance of the ice can translate into a melting icecaps and sea level rise of several meters “adds Escutia.
As noted by CSIC researcher,” the disappearance of the shield allowed ocean currents carried by the winds to penetrate to the base of the caps, causing it to thaw. “
The study raises a potential widespread melting of Antarctic oriental cap in the future if carbon dioxide levels are not reduced in the atmosphere .
In addition, the work “helps to solve the mystery of how they contribute to the Earth’s orbit around the Sun in the stability of the ice sheets, “stated CSIC researcher.
No comments:
Post a Comment