Large scale modeling of the transport, the chemical transformation and the mass budget of the sulfur emitted during the eruption of April 2007 by the Piton de la Fournaise
Abstract. During April 2007, the Piton de la Fournaise volcano, La Réunion island, entered in its bigger eruption registered at least one century. Due to the absence of rapid captor in the vicinity of the volcano, the estimation of the degassing during the paroxysmal phase of the event has not been estimated. A modeling study that uses the mesoscale chemical model MesoNH-C, the spatial observation from the OMI sensor and the CALIOP spacelidar, have simulated the global mass of SO2 observed and the general shape of the SO2 plume spreading over the Indian ocean. Moreover, an analysis of the budget of the SO2 plume have permitted to estimate the total SO2 release to 159 Kt, the transformation in H2SO4 at 46.9 Kt and the surface dry deposition to 22 Kt and 17.9 Kt of SO2 and H2SO4 respectively. Then, this top down approach has retrieved an estimation of the temporal evolution of the SO2 emission during the most active period of the eruption, where the peak of degassing is estimated to 2000 kg s−1 in the morning of the 6 April. This temporal evolution of SO2 emission, given here, can also be used for more local studies.