Context. Since April 5, 2008 and up to February 15, 2017, the SOLar SPECtrometer (SOLSPEC) instrument of the SOLAR payload on board the International Space Station (ISS) has performed accurate measurements of solar spectral irradiance (SSI) from the middle ultraviolet to the infrared (165 to 3088 nm). These measurements are of primary importance for a better understanding of solar physics and the impact of solar variability on climate. In particular, a new reference solar spectrum (SOLAR-ISS) is established in April 2008 during the solar minima of cycles 23-24 thanks to revised engineering corrections, improved calibrations, and advanced procedures to account for thermal and aging corrections of the SOLAR/SOLSPEC instrument. Aims. The main objective of this article is to present a new high-resolution solar spectrum with a mean absolute uncertainty of 1.26% at 1σ from 165 to 3000 nm. This solar spectrum is based on solar observations of the SOLAR/SOLSPEC space-based instrument. Methods. The SOLAR/SOLSPEC instrument consists of three separate double monochromators that use concave holographic gratings to cover the middle ultraviolet (UV), visible (VIS), and infrared (IR) domains. Our best ultraviolet, visible, and infrared spectra are merged into a single absolute solar spectrum covering the 165-3000 nm domain. The resulting solar spectrum has a spectral resolution varying between 0.6 and 9.5 nm in the 165-3000 nm wavelength range. We build a new solar reference spectrum (SOLAR-ISS) by constraining existing high-resolution spectra to SOLAR/SOLSPEC observed spectrum. For that purpose, we account for the difference of resolution between the two spectra using the SOLAR/SOLSPEC instrumental slit functions. Results. Using SOLAR/SOLSPEC data, a new solar spectrum covering the 165-3000 nm wavelength range is built and is representative of the 2008 solar minimum. It has a resolution better than 0.1 nm below 1000 nm and 1 nm in the 1000-3000 nm wavelength range. The new solar spectrum (SOLAR-ISS) highlights significant differences with previous solar reference spectra and with solar spectra based on models. The integral of the SOLAR-ISS solar spectrum yields a total solar irradiance of 1372.3 ± 16.9 Wm −2 at 1σ, that is yet 11 Wm −2 over the value recommended by the International Astronomical Union in 2015.

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The accurate measurement of the solar spectrum at the top of the atmosphere and its variability are fundamental inputs for solar physics (Sun modeling), terrestrial atmospheric photochemistry and Earth's climate (climate's modeling). These inputs were the prime objective set in 1996 for the SOLAR mission. The SOLAR package represents a set of three solar instruments measuring the total and spectral absolute irradiance from 16 nm to 3088 nm. SOLAR was launched with the European Columbus space laboratory in February 2008 aboard the NASA Space Shuttle Atlantis. SOLAR on the International Space Station (ISS) tracked the Sun until it was decommissioned in February 2017. The SOLar SPECtrum (SOLSPEC) instrument of the SOLAR payload allowed the measurement of solar spectra in the 165 -3000 nm wavelength range for almost a decade. Until the end of its mission, SOLAR/SOLSPEC was pushed to its limits to test how it was affected by space environmental effects (external thermal factors) and to better calibrate the space-based spectrometer. To that end, a new solar reference spectrum (SOLAR-ISS -V1.1) representative of the 2008 solar minimum was obtained from the measurements made by the SO-LAR/SOLSPEC instrument and its calibrations. The main purpose of this article is to improve the SOLAR-ISS reference spectrum (between 165 and 180 nm in the far ultraviolet, between 216.9 and 226.8 nm in the middle ultraviolet, and

We thank the reviewer for the detailed remarks and the effort to improve our paper. We responded to all comments as best as we can. We attached Section 5.2 (comparisons of data sets) of the changed manuscript to the answers. General comments: This paper deals with new progress about the instrumental corrections of the SCIA-MACHY data. The special interest is to improve the solar spectral data. The paper is well written and contains interesting and important results for users of SCIAMACHY C1

We thank the reviewer for the detailed remarks and the effort to improve our paper. We responded to all comments as best as we can. Section 5.2 of the manuscript with marked changes is attached to the answers. In general, this is a good paper and I recommend only a few minor corrections. Section 3.4 is about the aging correction for the WLS. As I understand your text, the WLS is only used to make a flat-field correction to the detector array.