IG reported that activity continued at Reventador during 15-21 February.
Satellite images showed a thermal anomaly on the NE flank from the lava flow that was observed on 12 February.
Clouds prevented views on 17, 19, and 21 February.
Based on analysis of satellite imagery, the Washington VAAC reported an ash plume that drifted 19 km SE on 16 February.
IG observed an ash plume that rose 100 m above the crater on 18 February.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)