Teams of scientists sailing to Antarctica's Thwaites Glacier, nicknamed the Doomsday Glacier, are having trouble getting there.

After two years when summer ice melt had been minimal, last summer shattered all records with 586 billion tons (532 billion metric tons) of ice melting, according to satellite measurements reported in a study Thursday. Thats far more than the yearly average loss of 259 billion tons (235 billion metric tons) since 2003 and easily surpasses the old record of 511 billion tons (464 billion metric tons) in 2012, said a study in Nature Communications Earth & Environment. Last years Greenland melt added 0.06 inches (1.5 millimeters) to global sea level rise. While general ice melt records in Greenland go back to 1948, scientists since 2003 have had precise records on how much ice melts because NASA satellites measure the gravity of the ice sheets. As massive as the melt was last year, the two years before were only on average about 108 billion tons (98 billion metric tons).