JIRAM observations of Jupiter's upper troposphere

The Jovian Infrared Auroral Mapper (JIRAM, a payload element of the NASA Juno mission to Jupiter) includes an infrared spectrometer covering the 2.0–5.0 μm range. After reviewing the main results on the conditions of upper troposhere derived from the solar-dominated 2.0–3.2 μm spectral range and presented in Grassi et al. 2021, we focus our discussion on open modeling issues and recent attempts to study these altitudes from data in the thermal-dominated 4.0-5.0 μm spectral range. We present also the results of an automatic classification of data performed on the basis of the HDBSCAN algorithm (McInnes et al. 2017). We show that similar spatial patterns are obtained either considering the coefficents of a PCA performed directly on spectra or on the physical parameters (clouds altitude, haze thickness) retrieved by the algorithm adopted in Grassi et al. 2021. Grassi et al. 2021 doi:10.1093/mnras/stab740McInnes et al. 2017 doi:10.21105/joss.00205