Worldwide Annual Glacial Mass Balance

Worldwide annual glacial mass balance

Annual mass balance of glaciers worldwide from 1980 to 2012

A) indicates a positive cumulative annual mass balance.
B) shows a negative cumulative annual mass balance.
C) has fluctuated greatly,with some positive and some negative years.
D) trends near zero,indicating snowfall and melting are mostly equal.
E) was positive through 1995 and has been slightly negative since.