Skip to content
Skip to main content
Author: Nikola Rogic

Automated, satellite-based volcano monitoring

Updated Tuesday, 29 May 2018
Less than 10% of the ∼1500 active subaerial volcanoes around the world are monitored with appropriate frequency says PhD student, Nikola Rogic.

This page was published over 1 year ago. Please be aware that due to the passage of time, the information provided on this page may be out of date or otherwise inaccurate, and any views or opinions expressed may no longer be relevant. Some technical elements such as audio-visual and interactive media may no longer work. For more detail, see how we deal with older content.

Cleveland Volcano, Aleutian Islands, Alaska A view from space of Mount Cleveland volcano, Aleutian Islands, Alaska (2006)

A combination of passive and active remote sensing (RS) is accepted to be a technological solution for bridging critical gaps in volcanic hazard assessment and risk mitigation. Whereas many examples of satellite-borne volcano monitoring are known since the early Eighties, we note that the exceptionally large literature available on optical (passive) remote sensing of very-high temperature features, lacks in detailed information on some key-parameters. In particular, spectral emissivity and its behaviour at high-to-very high temperatures. 


What is Spectral Emissivity?

Defined as the efficiency with which a surface radiates its thermal energy – spectral emissivity is seldom measured and is mostly assumed or estimated. Nonetheless, it is a critical variable in space-borne volcano monitoring due to its close relationship with Land Surface Temperature (LST) values and the inherent impact on the estimate of mass eruption rates. 


To fill this gap in knowledge, we designed a multi-stage experiment to measure spectral emissivity of rock samples collected in a grid, scaled to the spatial resolution of High-Resolution multispectral payloads provided with Thermal Infra-Red (TIR) channels – in particular, Terra’s ASTER and Landsat 8’s TIRS – from which spectral emissivity can be derived.


The aim

This approach will:

estimate the lateral spatial heterogeneity of spectral emissivity on ground at known volcanic targets

assess the capacity of reproducing it from space-borne observations at the scale of a satellite image/pixel

develop a method for incorporating the experimental laws into the techniques of automated eruption detection and quantitative monitoring.  


Development of a general method

The suite of lava flow samples from Mount Etna, Italy (1999 - 2017) were investigated (spectral emissivity measured), using laboratory-based Fourier Transform Infra-Red (FTIR) spectroscopy at 0.4 to 14.5 μm wavelength range and moderate-to-high temperatures (400 K to 1000 K). 

Mt. Etna on Sicily displays a steam plume from its summit Mt. Etna on Sicily displays a steam plume from its summit (1994)


The initial investigation of spectral emissivity valuation assesses the correlation of laboratory measured data with (i) petrological composition, (ii) sample properties, and (iii) high-resolution RS data of the same target. 
Measured spectral emissivity results are further used in remote sensing applications to constrain very high-temperature thermal anomalies (i.e. active lava flows with integrated pixel temperatures - close to or above 1000 K) and in melt mass flux investigations.

Like science? Go further with the OU

 

Become an OU student

Author

Ratings & Comments

Share this free course

Copyright information

Skip Rate and Review

For further information, take a look at our frequently asked questions which may give you the support you need.

Have a question?