The Far INfrarEd Spectrometer for Surface Emissivity (FINESSE) Part I: Instrument description and level 1 radiances (data set)

The data set uploaded to this repository is outlined in a manuscript submitted to the journal Atmospheric Measurement Techniques.

A. BB_effective_emissivity:                            Holds the data set used to characterise instrument calibration target emissivity

B. ILS_data:                                                   Holds the data set used to model the instrument spectral lineshape

C. Time_resolved_spectral_response:           Holds the data set establishing the spectral stability of the instrument

D. Zenith_radiances_20220323_1100UTC:   Holds calibrated radiances acquired by FINESSE to demonstrate it accuracy and precision. Also included in this file is an LBLRTM simulation using coincident ERA5 profile information for the time and location of the observations

The Far INfrarEd Spectrometer for Surface Emissivity (FINESSE). Part I: Instrument description and level 1 radiances

Jonathan E. Murray1,2, Laura Warwick3, Helen Brindley1,2, Alan Last1, Patrick Quigley1, Andy Rochester1, Alexander. Dewar1, Daniel. Cummins1

1 Department of Physics, Imperial College London, SW7 2BX, UK

2 National Centre for Earth Observation, UK

3 ESA-ESTEC, Noordwijk, Netherlands

In the manuscript Part (I) we describe the FINESSE system configuration, outlining the FINESSE spectral characteristics, the data acquisition methodology and the calibration strategy. As part of the process, we evaluate the stability of the system, including the impact of knowledge of blackbody target emissivity and temperature.  We also establish a numerical description of the instrument line shape.  We demonstrate why it is important to account for these effects by assessing their impact on the overall uncertainty budget on the level 1 radiance products from FINESSE.