Fig. 4
From: Total (fumarolic + diffuse soil) CO2 output from Furnas volcano
CO2 concentrations (ppm) map at “Furnas Lake” survey (using TDL). GasFinder and retro-reflectors positions are shown with letters and numbers, respectively. Investigated fumaroles (WJ, ST, and MP; red crossed-circles), Multi-GAS measurement-point (blue triangle), and the GFUR2 meteo station positions are given. The principal directions of plume/wind dispersal are given (rose diagram). The CO2 flux was estimated integrating the concentration values (>600 ppm) inside the black dashed lines, close to the main fumaroles and downwind dispersal direction