**5. Conclusions**

Landsat 8 satellites offer a unique opportunity for monitoring volcanic plumes at a high spatial resolution together with the opportunity to study volcanic eruptions back in time by exploiting the data archives. De Michele et al. [21] presented a method to extract the PEM (i.e., the digital elevation model of a volcanic plume) from raw Landsat 8 data. Nevertheless, raw Landsat 8 data are not available to the general public, limiting de facto the straight-forward application of the method. Moreover, the Landsat 8 OLI sensor presents a staggered geometry, which needs tuned processing. In this study, we push the methodology forward: Here we present a generalized, simplified methodology to extract the VCTH as a PEM from the common push broom staggered sensors, such as the standard Landsat 8 products. The advantages are manifold. First, it takes advantage of the freely available Landsat 8 data archives. Second, the method exploits the already-orthorectified Landsat 8 dataset, which is a standard Landsat 8 product, readily available on Landsat 8 archives. Third, the method could be adapted to the Copernicus Sentinel 2 data, a staggered sensor for which the products available to general public are orthorectified (similar to Landsat 8). The synergetic use of multiple sensors could improve the revisit time over a given volcanic eruption. It represents a step towards the routine monitoring of volcanic plumes height from space, at high spatial resolution.

The VCTH retrievals obtained from the geostationary SEVIRI and the polar MODIS satellite instruments indicate a good agreement with the Landsat VCTH product.

**Funding:** This study benefited from funding of the European Union and BRGM within the APHORISM (Advanced Procedures for Volcanic and Seismic Monitoring) project, 7th framework programme of the European Union. We are thankful to NASA/USGS Landsat 8 program for the Landsat 8 OLI data.

**Acknowledgments:** We are thankful to NASA/USGS for the Landsat8 data.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**


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