Report on Cleveland (United States) — 14 February-20 February 2001
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 14 February-20 February 2001
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2001. Report on Cleveland (United States). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 14 February-20 February 2001. Smithsonian Institution and US Geological Survey.
52.825°N, 169.944°W; summit elev. 1730 m
All times are local (unless otherwise noted)
The AVO reported that Cleveland volcano erupted explosively at 0600 on 19 February, producing an ash-and-steam cloud that was detected from the beginning of the eruption on GOES imagery and confirmed by pilot reports at 1310. Satellite imagery at 0945 showed that the cloud was in two sections; the lower section reached ~5.2 km a.s.l. and drifted SE of Cleveland, and the higher section reached 9.1-10.7 km a.s.l. and drifted to the N. By 1900 the cloud had extended at least 120 km to the N and drifted E towards Dutch Harbor, Akutan, and beyond. The National Weather Service via the Anchorage VAAC, and the Federal Aviation Administration, issued a volcanic ash advisory to divert aircraft away from the ash cloud. During 1200 to about 1600, light ash fell in the closest inhabited town to the volcano, Nikolski (~30 residents), 45 miles E of the volcano. The Anchorage VAAC reported that additional eruptions occurred through 1800. According to the AVO, explosive activity ended in the late afternoon and at 2130 a thermal anomaly was still visible on satellite imagery. Prior to the eruption the AVO had received pilot reports and photos of increased emissions on 2 February, but the reports could not be confirmed without ground-based monitoring instrumentation. The AVO warned that further eruptive activity could occur with little warning. Because Cleveland is not seismically monitored, the AVO did not assign a level of concern color code.
GOES images and animation of the 19 February ash cloud
Geologic Background. The beautifully symmetrical Mount Cleveland stratovolcano is situated at the western end of the uninhabited Chuginadak Island. It lies SE across Carlisle Pass strait from Carlisle volcano and NE across Chuginadak Pass strait from Herbert volcano. Joined to the rest of Chuginadak Island by a low isthmus, Cleveland is the highest of the Islands of the Four Mountains group and is one of the most active of the Aleutian Islands. The native name, Chuginadak, refers to the Aleut goddess of fire, who was thought to reside on the volcano. Numerous large lava flows descend the steep-sided flanks. It is possible that some 18th-to-19th century eruptions attributed to Carlisle should be ascribed to Cleveland (Miller et al., 1998). In 1944 it produced the only known fatality from an Aleutian eruption. Recent eruptions have been characterized by short-lived explosive ash emissions, at times accompanied by lava fountaining and lava flows down the flanks.