Resumen

JIMENEZ-ESCALONA, José Carlos; MONSIVAIS-HUERTERO, Alejandro; DELGADO-GRANADOS, Hugo  y  HUERTA-CHAVEZ, Oliver Maciel. Comparison between measurements of SO₂ emission flux by means of COSPEC and MODIS, and their complementarity in the volcanic assessment: Case study in the Popocatépetl volcano (Mexico). Bol. Soc. Geol. Mex [online]. 2018, vol.70, n.3, pp.709-729. ISSN 1405-3322.  https://doi.org/10.18268/bsgm2018v70n3a7.

One of the main elements monitored in volcanic emissions is SO2 due to the contrast of concentrations between the volcanos compared to the background of the atmosphere. Different methodologies have been developed from remote sensing techniques from the ground and from space. In particular, the COSPEC technique has been used efficiently from terrestrial vehicles, allowing the emission rate of SO2 with estimated relative errors of ± 13% to ± 42% to be obtained. However, the logistics required to carry out continuous measurement campaigns in the Popocatepetl area, allows exclusively 2 or 3 measurements a month and only during daylight hours. Another type of methodology based on remote sensing is the processing of satellite images in the thermal infrared. In this case, the use of MODIS images allows obtaining daily SO2 information both in images taken at daylight hours or during the night period, which gives a maximum temporal resolution of images for the sensor in the study area (maximum 4 images per day). In order to construct time series from both techniques, the flux of SO2 derived from the COSPEC sensor are used as a reference, which allows the MODIS image identification within the area of the plume that was sampled with the COSPEC sensor. We aim to propose an adjustment methodology to reconstruct the information with the aforementioned values. Between November 2006 to February 2007 in the Popocatepetl volcano area, we found a good match between the two techniques, which indicates that the adjustment methodology proposal to obtain data calibration equations could be applied during periods of time when simultaneous data from both sensors are available.

Palabras llave : volcano monitoring; remote sensing; MODIS; COSPEC.

        · resumen en Español     · texto en Español     · Español ( pdf )