Fig. 4
From: Dark zone of the Greenland Ice Sheet controlled by distributed biologically-active impurities
Photograph showing close-up of bare ice found in the ablation zone. The photographs were taken near the field camp located close to the S6 automated weather station at ~1000 m a.s.l. (Fig. 1). a Ice containing distributed impurities on the surface and b clean ice with cryoconite holes
