TROPOMI enables high resolution SO flux observations from Mt. Etna, Italy, and beyond.

The newly launched imaging spectrometer TROPOMI onboard the Sentinel-5 Precursor satellite provides atmospheric column measurements of sulfur dioxide (SO) and other gases with a pixel resolution of 3.5 × 7 km. This permits mapping emission plumes from a vast number of natural and anthropogenic emitters with unprecedented sensitivity, revealing sources which were previously undetectable from space.

Portable laser spectrometer for airborne and ground-based remote sensing of geological CO emissions.

A 24 kg, suitcase sized, CW laser remote sensing spectrometer (LARSS) with a ~2 km range has been developed. It has demonstrated its flexibility in measuring both atmospheric CO from an airborne platform and terrestrial emission of CO from a remote mud volcano, Bledug Kuwu, Indonesia, from a ground-based sight. This system scans the CO absorption line with 20 discrete wavelengths, as opposed to the typical two-wavelength online offline instrument.

Differential absorption lidar for volcanic CO(2) sensing tested in an unstable atmosphere.

Motivated by the need for an extremely durable and portable instrument to quantify volcanic CO(2) we have produced a corresponding differential absorption lidar (DIAL). It was tested on a volcano (Vulcano, Italy), sensing a non-uniform volcanic CO(2) signal under turbulent atmospheric conditions. The measured CO(2) mixing ratio trend agrees qualitatively well but quantitatively poorly with a reference CO(2) measurement.

Cavity ring-down absorption spectrography based on filament-generated supercontinuum light.

We performed simultaneous, multispectral CRDS measurements that for the first time use the Supercontinuum light source. We called this approach Supercontinuum Cavity Ring-Down Spectrography (SC CRDSpectrography) and successfully applied it to measuring the absorption spectrum of NO2 gas at a concentration of 2 ppm. The extrapolated sensitivity of our setup was much greater, about 5 ppb.