firn

n.

粒雪；积雪；冰原；万年雪

1. Snow has lasted for several days in many districts and the firn is considered as the most serious one during the last 50 years.
   在许多地区，大雪已连续下了很多天，积雪被称为五十年来最严重的一次。

Firn Densification: An Empirical Model
The age of the air in the firn and ice at Summit, Greenland
Aspects of Plant Intelligence: an Answer to Firn
Loss of volatile acid species from upper firn layers at Vostok, Antarctica
Sulfate and nitrate firn concentrations on the Greenland ice sheet: 1. Large-scale geographical deposition changes
A record of atmospheric halocarbons during the twentieth century frompolar firn air
Relationship between chemistry of air, fresh snow and firn cores for aerosol species in coastal Antarctica
Atmospheric gas concentrations over the past century measured in air from firn at the South Pole
Natural and anthropogenic changes in atmospheric CO2 over the last 1000 years from air in Antarctic ice and firn
Natural and anthropogenic changes in atmospheric CO 2 over the last 1000 years from air in Antarctic ice and firn