Statistical analysis of the long-range transport of the 2015 Calbuco volcanic eruption from ground-based and space-borne observations

BEGUE, NELSON; PALLOTTA, JUAN V.; MBATHA, NKANYISO; RANAIVOMBOLA, MARION; SHIKWAMBAN, LERATO; VENKATARAMAN, SIVA; ORTE, FACUNDO; PIKETH, STUART; BENCHERIF, PROF. HASSAN BENCHERIF; WOLFRAM, ELIAN; DU PREEZ, DAVID JEAN; FORMENTI, PAOLA

ANNALES GEOPHYSICAE

COPERNICUS PUBLICATIONS

Lugar: Gottingen; Año: 2020 vol. 38 p. 395 - 420

0992-7689

This study treats on the influence of the 2015 Calbuco eruption (41.2°S, 72.4°W; Chile) on the total columnar aerosols optical properties over the Southern Hemisphere. The well-known technic of sunphotometry was applied for investigation of the transport and the spatio-temporal evolution of the optical properties of the volcanic plume. The CIMEL sunphotometer measurements performed over 6 South American and 3 African sites were statistically analyzed. This study involves also the use of the satellite observations and back-trajectory model. The passage of the Calbuco plume is statistically detectable on the aerosol optical depth (AOD) obtained from sunphotometer and MODIS observations. This statistical detection confirms that the majority of the plume was transported over the northeastern parts of South America and reaching the South African region one week following the eruption. The plume has impacted to a lesser extent the southern parts of South America. The highest AOD anomalies were observed over the northeastern parts of the South America. Over the South African sites, the AOD anomalies induced by the spread of the plume were quite homogeneously distributed between the east and west coast. The optical characteristics of the plume near source region were consistent with a bearing-ash plume. Conversely, the remote sites to the Calbuco volcano were influenced by ash-free plume. The opticalproperties discuss on this paper will be used as inputs for numerical models for further investigation on the ageing of the Calbuco plume in a forthcoming study.