Assertion: glacier's ice | /r/HasProperty | 900 kg
Facets:
Source sentences:
text: A first density scenario (a) assumes all glacier thickness changes are loss and gain of ice (900 kg m−3), a second density scenario (b) assumes 900 kg m−3 for thickness changes over ice and 600 kg m−3 for changes over firn and snow (Table 1, Supplementary Information).
text: Glaciers are made of several materials with different densities (given in units of kg m-3): snow that fell in the most recent winter (200-500 kg m-3), firn (snow from previous winters, 500-900 kg m-3) and ice (900 kg m-3).
text: Liquid water from melt and rain percolates through the firn column, and is either held as irreducible water or refreezes, progressively reducing pore space from bottom to top layers until the entire firn column turns into ice (900 kg m−3) and no additional water can be stored.