From year to year, the ice around the Arctic ebbs and flows, reaching a minimum and maximum as the temperature shifts through the seasons.
원문출처 : http://www.cnn.com/2016/11/02/us/old-arctic-sea-ice-vanishing/index.html
원문출처 : http://www.cnn.com/2016/11/02/us/old-arctic-sea-ice-vanishing/index.html