SO2 emissions during the post-eruptive phase of the Tajogaite eruption (La Palma, Canary Islands) by means of ground-based miniDOAS measurements in transverse mode using a car and UAV
Authors: Rodríguez Oscar , Barrancos José , Cutillas Juan , Ortega Victor , Hernández Pedro A. , Cabrera Iván , Pérez Nemesio M. 
Published: February 2023

Throughout the 85 days that lasted the Tajogaite eruption at Cumbre Vieja volcano (La Palma, Canary Islands, Spain), observations of SO2 emissions were made using ground-based instruments, in transverse mode, static scanners and on-board drones, as well as by numerous satellite instruments. The initial estimates of the total SO2 emission from the eruption were 2.4 Mt from TROPOMI and 1.2 Mt from the traverse data. These measurements formed part of the official monitoring effort, providing insights into the eruption&#8217;s evolution and informing the civil defence response throughout the eruption (Hayer C. et al., 2022; Albertos V. T. et al., 2022). Once the Tajogaite eruption was over, we continued performing a SO2 monitoring release to the atmosphere by the Tajogaite volcanic vent since the low ambient concentrations of SO2 make it an ideal volcanic gas monitoring candidate even during the post-eruptive phase. SO2 measurements had been carried out a using a car-mounted and UAV-mounted ground-based miniDOAS measurements throughout this post-eruptive phase. About 80 measurements of SO2 emission rates were performed from December 15, 2021 to December 17, 2022. The standard deviation of the estimated values obtained daily was ~ 20%. The range of estimated SO2 emission values has been from 670 to 17 tons per day, observing a clear decreasing trend of SO2 emissions during the post-eruptive phase. During the first month of the post-eruptive phase, it was observed that the average value of the estimated SO2 emission was about 219 tons/day, while it dropped to 107 tons/day during the second and third month after the end of the Tajogaite eruption. This average value continued decreasing during the fourth month of the post-eruptive phase, about 67 tons/day, and recently measurements provide an average SO2 emission value of 13 tons/day. These relatively low observed SO2 emissions during the post eruptive of the Tajogaite eruption phase seems to be clearly related to shallow magma cooling processes within the Tajogaite volcanic edificie.Hayer, C., Barrancos, J., Burton, M., Rodr&#237;guez, F., Esse, B., Hern&#225;ndez, P., Meli&#225;n, G., Padr&#243;n, E., Asensio-Ramos, M., and P&#233;rez, N.: From up above to down below: Comparison of satellite- and ground-based observations of SO2 emissions from the 2021 eruption of Cumbre Vieja, La Palma, EGU General Assembly 2022, Vienna, Austria, 23&#8211;27 May 2022, EGU22-12201, https://doi.org/10.5194/egusphere-egu22-12201, 2022.Albertos, V. T., Recio, G., Alonso, M., Amonte, C., Rodr&#237;guez, F., Rodr&#237;guez, C., Pitti, L., Leal, V., Cervig&#243;n, G., Gonz&#225;lez, J., Przeor, M., Santana-Le&#243;n, J. M., Barrancos, J., Hern&#225;ndez, P. A., Padilla, G. D., Meli&#225;n, G. V., Padr&#243;n, E., Asensio-Ramos, M., and P&#233;rez, N. M.: Sulphur dioxide (SO2) emissions by means of miniDOAS measurements during the 2021 eruption of Cumbre Vieja volcano, La Palma, Canary Islands, EGU General Assembly 2022, Vienna, Austria, 23&#8211;27 May 2022, EGU22-5603, https://doi.org/10.5194/egusphere-egu22-5603, 2022.