 Jan Carstensz 's 1623 report of glaciers covering the equatorial mountains of New Guinea was originally met with ridicule , but in the early 20th century at least five subranges of the <unk> Mountains ( meaning " Snowy Mountains " ) were indeed still found to be covered with large ice caps . Due to the location of the island within the tropical zone , there is little to no seasonal variation in temperature . The tropical location has a predictably steady level of rain and snowfall , as well as cloud cover year round , and there has been no noticeable change in the amount of moisture which has fallen during the 20th century . 
