scientist might have finally worked out how Antarctica was speedily buried in a thick sheet of ice 34 million age ago . They trust that two factors contributed to glaciation of the southernmost continent . Their research is write inNature Geoscience .
The Drake Passage ( the area between South America and Antarctica ) deepened , exchange how body of water circulated in the oceans globally . The change agitate the counseling of the warmer currents coming from the tropics , which were manoeuvre to northern latitude .
The other contribution comes from the diminution of carbon copy dioxide in the atmosphere . CO2levels have been decline since the start of the Cenozoic Era 66 million days ago , but the sudden modification in the ocean current led to more rain , which impart CO2below the decisive economic value . This mean’t Antarctica became frozen .
" It ’s an interesting lesson for us when it comes to climate change because what we get is a thumbnail shift between two static climatic state in Antarctica – from no glacier to glacier , ” say co - writer Dr. Galen Halverson , from McGill University , in astatement . “ And what we see is both how complex climate change can be and how unplumbed an effect changing patterns of ocean circulation can have on global climate states , if looked at on a geological fourth dimension scale . "
The two factor were encounter before as private-enterprise explanation for the ice of the South Pole , but the investigator realize they were two sides of the same coin .
agree to the scientist , the deepening of the Drake Passage commence the powerful Antarctic Circumpolar Current . The looped current keep the cooler water near the continent and act as a barrier from the warm , less salty body of water from the North Atlantic and Central Pacific .
Those stream were redirected towards the other continents , increase rainfall . Rainfall increase the amount of weathering of rocks , a process that slowly traps the atmospheric CO2inside limestone .
The researchers call back that nobody considered combining the two idea before because they happen on unlike timescales . Currents change over yard of eld , while rock weathering happens over hundreds of thousands of class . But once combine , they were believably enough to immerse Antarctica in ice and snow .
