Agence France-Presse: The Greenland ice sheet, a potentially massive contributor to land-encroaching sea-level rise, lost mass twice as fast between 2003 and 2010 as during the entire 20th century, researchers said on Wednesday. Greenland ice loss contributed to a global average sea level rise of 25mm between 1990 and 2010 - mainly from surface melt, said the research published in the journal Nature. The total mass lost was over 9 000 gigatons (about one billion tons). It was net loss, meaning the difference between...