Lava from a volcano. Credit: pxhere

Eruption of Calbuco Volcano, Chile

22 April 21:38 UTC and 27 April 2015

Lava from a volcano. Credit: pxhere
Lava from a volcano. Credit: pxhere

Southern Chile’s Calbuco volcano unexpectedly erupted for the first time in more than 40 years on 22 April, and then again early on 23 April.

Last Updated

15 September 2022

Published on

22 April 2015

By Jochen Kerkmann, Mark Higgins, Vesa Nietosvaara and Michael Grzegorski (EUMETSAT) and HansPeter Roesli (Switzerland)

The Meteosat-10 Dust RGB shows the plume from the second eruption, as it headed towards Chile, Argentina and Uruguay at 05:00 UTC on 24 April.

The eruption caused air traffic disruptions with a number of international flights cancelled or delayed. Qantas flight QF27 was five hours into its journey to Santiago when it had to turn back to Sydney.

 Meteosat-10 DUST RGB, 24 April 05:00 UTC, showing the ash plume in yellow
Figure 1: Meteosat-10 Dust RGB, 24 April 05:00 UTC, showing the ash plume in yellow
 GOES-13, 22 April 21:38 UTC
Figure 2: GOES-13 Visible, 22 April 21:38 UTC. Credit: Dan Lindsey, CIRA
 
 GOES-13, 22 April 20:38 UTC to 23 April 13:38 UTC
Figure 3: GOES-13 Infrared, 22 April 20:38 UTC to 23 April 13:38 UTC. Credit: Dan Lindsey, CIRA

The Calbuco volcano in southern Chile erupted around 21:03 UTC on 22 April, as can be seen on the GOES-13 visible image from 21:38 UTC (Figure 2) and the infrared animation from 22 April 20:38 UTC to 23 April 13:38 UTC (Figure 3).

 Suomi-NPP , 23 April 05:13 UTC.
Figure 4: Suomi-NPP VIIRS I-band 5 (11.4µm), 23 April 05:13 UTC. Credit: Dan Lindsey, CIRA
 Suomi-NPP, 23 April 05:12 UTC
Figure 5: Suomi-NPP VIIRS Volcanic Ash RGB, 23 April 05:12 UTC

There was a second explosive eruption that began some time before the Suomi-NPP VIIRS image from 05:13 UTC (Figure 4). The I-band 5 (11.4µm) minimum brightness temperature within the overshooting top of the second plume was -101°C, which is extraordinary for mid-latitudes and indicates a cloud top height of well above 15km.

The volcanic cloud from the second eruption can also be seen in the VIIRS Ash RGB product (Figure 5) close to the position of the Calbuco volcano in the lower part of the image. The colour (brown) indicates a very thick ash cloud. The cloud from the first pulse is visible more to the north (red and yellow colours), stretching east-west along a deformation zone. The yellow colour indicates the presence of SO2 inside the plume (probably together with the presence of small ash particles).

 
 Aqua, 24 April 2015, 06:35 UTC
Figure 6: Aqua MODIS retrievals, 24 April 2015, 06:35 UTC. Credit: Mike Pavolonis (NOAA/NESDIS)
 
 CALIPSO, 24 April 2015, 18:22 UTC
Figure 7: CALIPSO, 24 April 2015, 18:22 UTC. Credit: Mike Pavolonis (NOAA/NESDIS). Full Resolution

About one hour later, Aqua MODIS also captured the volcanic plumes (Figure 6). Note that no retrievals are present in the core of the cloud produced by the second explosion due to its large optical depth. The MODIS retrievals show small effective radii in the eastern, and highest portion, of the dispersed cloud (yellow colour in the Ash RGB product, top left) from the first eruption. The relatively small area of larger heights in the western portion of the dispersed cloud are likely an artifact of the unsupervised, near-real time retrieval process.

Unfortunately, the volcanic clouds were located near the edge of the Aqua MODIS morning pass, which means that a CALIPSO overpass above the cloud was not available (CALIPSO and Aqua fly in nearly the same orbit, offset by a few minutes). But the CALIPSO afternoon overpass captured the volcanic plume, the portion of the cloud overpassed by CALIOP was as high as about 17–18km (Figure 7).

 
 Suomi-NPP, 23 April 19:10 UTC
Figure 8: Suomi-NPP Natural Colour RGB, 23 April 19:10 UTC
 
  Suomi-NPP, 23 April 19:10 UTC
Figure 9: Suomi-NPP VIIRS Volcanic Ash RGB, 23 April 19:10 UTC

A daytime view of the volcanic clouds was provided by Suomi-NPP VIIRS on 23 April at 19:10 UTC (Figures 8 and 9). At this time, the volcanic clouds stretch from the west to the east coast of southern South America.

In the Ash RGB product (Figure 9), most of the cloud, which is getting thinner as it moves away from the Calbuco volcano, is yellow (ash and SO2 mixed), but there is also a larger red area ('pure' ash cloud) and a small cyan-green band close to Santiago ('pure' SO2 cloud with some remaining ash particles).

 
 Metop A&B GOME-2, 23 April 2015
Figure 10: Metop A&B GOME-2 SO2 vertical column product, 23 April.
 
 AIRS, 23 April 2015
Figure 11: AIRS SO2 vertical column product, 23 April. Credit: Fred Prata. AIRS SO2 retrievals for 23–29 April

The presence of SO2 in the yellow and cyan parts of the volcanic cloud is confirmed by GOME-2 (Figure 10) and AIRS (Figure 11) SO2 vertical column products.

 
 Meteosat-10, 24 April 05:00 UTC
Figure 12: Meteosat-10 Volcanic Ash RGB, 24 April 05:00 UTC. Download ash animation , 23 April 00:00 UTC–27 April 06:00 UTC.
 
 Meteosat-10, 24 April 05:00 UTC
Figure 13: Meteosat-10 Airmass RGB, 24 April 05:00 UTC. Download animation, 23 April 00:00 UTC–27 April 06:00 UTC

Although right on the edge the Meteosat-10 field of view, the volcanic plumes could also be seen on Ash and Airmass RGB imagery (Figures 12 and 13).

The Airmass RGB (Figure 13) is sensitive to high-level sulphur dioxide, because of the WV7.3 band that is used in combination with the WV6.2 in the red component of the RGB. The Ash RGB (Figure 12) is sensitive to both SO2 and ash clouds.

The animations above follow the plume of the Calbuco eruptions across the South Atlantic from 23 to 27 April. The Airmass RGB animation shows the high-level SO2 plume (bright red, gradually fading), as it crosses Argentina, Paraguay, Uruguay and Brazil (it reaches Buenos Aires at around 10:00 UTC on 24 April). In the second part of the animation, when the plume crosses the Atlantic and gets thinner, the colour of the SO2 plume gets 'weaker' (more orange), thus it is more difficult to distinguish it from regions with low upper-level humidity (also orange colour).

The Ash RGB animation shows both the ash (pink to magenta), SO2 (cyan-green) and ash mixed with SO2 (yellow). On its way to the mid Atlantic, the colour turns from mainly yellow to mainly cyan-green, hinting that the ash is falling down, leaving, essentially, only SO2 behind.

 Metop, 23–27 April
Figure 14: Metop GOME/AVHRR, 23–27 April. Aerosol optical depth over sea calculated by the Polar Multi-Sensor Aerosol Product (PMAp) from Metop. 
 Metop, 23–27 April
Figure 15: Metop GOME/AVHRR, 23–27 April. Volcanic ash classification flag (ash pixels labelled in red) calculated by the Polar Multi-Sensor Aerosol Product (PMAp) from Metop.

The Polar Multi-Sensor aerosol product retrieves aerosol optical depth over sea (Figure 14) and a volcanic ash classification flag (Figure 15, ash pixels marked in red) using GOME and AVHRR on Metop. The transport of the ash over sea can be clearly observed in both products.

Eruption of Calbuco Volcano, Chile
Figure 16: Metop A/B GOME-2, sulphur dioxide plume from Calbuco travelling eastward 22–27 April. Credit: EUMETSAT/O3SAF

The PMAp results are also in a very good agreement with the SO2 observations from GOME showing a strong plume moving eastwards. The operational sulphur dioxide products from GOME-2 Metop-A and -B are produced by the O3M SAF.

 

Additional content

Gravity Waves Associated with Calbuco Volcanic Eruption (CIMSS Blog)
Calbuco Volcano Erupts in Southern Chile (NOAA)
Tracking the Sulfur Dioxide from Calbuco (NASA Earth Observatory)
Time lapse video of the eruption (Rodrigo Barrera/YouTube)
Chile volcano Calbuco causes flight problems (BBC News)