Development of a new airborne hyperspectral imager for volcano observations

We developed a new airborne hyperspectral sensor, the Airborne Radiative Transfer Spectral Scanner (ARTS), for hyperspectral volcano observations. ARTS is a push-broom imaging spectrometer covering wavelengths from 380 to 2,450nm and 8,000 to 11,500nm with 421 bands. This study describes the ARTS system specifications and presents some in-flight performance test results obtained from the ARTS instrument overflight of the NIED building site, and the volcano observation flight over an active volcano (Sakurajima volcano) just after its eruption. At the NIED building site, the validation results indicate that the geo-correction accuracy is typically less than a two-pixel difference (RMS), and that there was good agreement between the predicted radiance at the sensor and the measured radiance at the sensor. At the Sakurajima volcano, we could detect the trace area of the pyroclastic flow caused by the eruption and the geothermal activities of Sakurajima crater. We conclude that ARTS is a well calibrated instrument for assessing volcanic activity and can be used for operational volcano observations.