New ground-based lidar enables volcanic CO2 flux measurements.
There have been substantial advances in the ability to monitor the activity of hazardous volcanoes in recent decades. However, obtaining early warning of eruptions remains challenging, because the patterns and consequences of volcanic unrests are both complex and nonlinear. Measuring volcanic gases has long been a key aspect of volcano monitoring since these mobile fluids should reach the surface long before the magma. There has been considerable progress in methods for remote and in-situ gas sensing, but measuring the flux of volcanic CO2-the most reliable gas precursor to an eruption-has remained a challenge. Here we report on the first direct quantitative measurements of the volcanic CO2 flux using a newly designed differential absorption lidar (DIAL), which were performed at the restless Campi Flegrei volcano. We show that DIAL makes it possible to remotely obtain volcanic CO2 flux time series with a high temporal resolution (tens of minutes) and accuracy (<30%). The ability of this lidar to remotely sense volcanic CO2 represents a major step forward in volcano monitoring, and will contribute improved volcanic CO2 flux inventories. Our results also demonstrate the unusually strong degassing behavior of Campi Flegrei fumaroles in the current ongoing state of unrest.
Dipartimento DiSTeM, Università di Palermo, Via Archirafi 36, 90123 Palermo, Italy.|Istituto Nazionale di Geofisica e Vulcanologia, Via la Malfa 143, 90146 Palermo, Italy.
Alessandro
A
Aiuppa
Diagnostics and Metrology Laboratory, ENEA, Via Enrico Fermi 45, 00044 Frascati, Italy.
Luca
L
Fiorani
Dipartimento DiSTeM, Università di Palermo, Via Archirafi 36, 90123 Palermo, Italy.|Guest of the Diagnostics and Metrology Laboratory, ENEA, Via Enrico Fermi 45, 00044 Frascati, Italy.
Simone
S
Santoro
Guest of the Diagnostics and Metrology Laboratory, ENEA, Via Enrico Fermi 45, 00044 Frascati, Italy.|Department of Industrial Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy.
Stefano
S
Parracino
Diagnostics and Metrology Laboratory, ENEA, Via Enrico Fermi 45, 00044 Frascati, Italy.
Marcello
M
Nuvoli
Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Bologna, via Donato Creti 12, 40128, Bologna, Italy.
Giovanni
G
Chiodini
Laboratorio di Chimica Ambientale ENEA, Piazzale Enrico Fermi 1, 80055 Portici, Italy.
Carmine
C
Minopoli
Dipartimento DiSTeM, Università di Palermo, Via Archirafi 36, 90123 Palermo, Italy.
Giancarlo
G
Tamburello