Abstract. The Radiation Explorer in the Far Infrared – Prototype for Applications and
Development (REFIR-PAD) is a Fourier transform spectroradiometer that has
been designed to operate from both stratospheric balloon platforms and
the ground. It has been successfully deployed in a stratospheric balloon flight
and several ground-based campaigns from high-altitude sites, including the
current installation at the Italian–French Concordia Antarctic station. The
instrument is capable of operating autonomously with only a limited need of
remote control and monitoring and provides a multiyear dataset of
spectrally resolved atmospheric downwelling radiances, measured in the
100–1500 cm−1 spectral range with 0.4 cm−1 resolution and a
radiometric uncertainty of better than 0.85 mW(m2srcm-1)-1.