Share Email Print

Proceedings Paper

Application of new techniques in the calibration of the TROPOMI-SWIR instrument (Conference Presentation)
Author(s): Paul Tol; Richard van Hees; Tim van Kempen; Matthijs Krijger; Sidney Cadot; Ilse Aben; Antje Ludewig; Jos Dingjan; Stefan Persijn; Ruud Hoogeveen
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

The Tropospheric Monitoring Instrument (TROPOMI) on-board the Sentinel-5 Precursor satellite is an Earth-observing spectrometer with bands in the ultraviolet, visible, near infrared and short-wave infrared (SWIR). It provides daily global coverage of atmospheric trace gases relevant for tropospheric air quality and climate research. Three new techniques will be presented that are unique for the TROPOMI-SWIR spectrometer. The retrieval of methane and CO columns from the data of the SWIR band requires for each detector pixel an accurate instrument spectral response function (ISRF), i.e. the normalized signal as a function of wavelength. A new determination method for Earth-observing instruments has been used in the on-ground calibration, based on measurements with a SWIR optical parametric oscillator (OPO) that was scanned over the whole TROPOMI-SWIR spectral range. The calibration algorithm derives the ISRF without needing the absolute wavelength during the measurement. The same OPO has also been used to determine the two-dimensional stray-light distribution for each SWIR pixel with a dynamic range of 7 orders. This was achieved by combining measurements at several exposure times and taking saturation into account. The correction algorithm and data are designed to remove the mean stray-light distribution and a reflection that moves relative to the direct image, within the strict constraints of the available time for the L01b processing. A third new technique is an alternative calibration of the SWIR absolute radiance and irradiance using a black body at the temperature of melting silver. Unlike a standard FEL lamp, this source does not have to be calibrated itself, because the temperature is very stable and well known. Measurement methods, data analyses, correction algorithms and limitations of the new techniques will be presented.

Paper Details

Date Published: 14 December 2016
PDF: 1 pages
Proc. SPIE 10000, Sensors, Systems, and Next-Generation Satellites XX, 100000U (14 December 2016); doi: 10.1117/12.2241242
Show Author Affiliations
Paul Tol, SRON Netherlands Institute for Space Research (Netherlands)
Richard van Hees, SRON Netherlands Institute for Space Research (Netherlands)
Tim van Kempen, SRON Netherlands Institute for Space Research (Netherlands)
Matthijs Krijger, SRON Netherlands Institute for Space Research (Netherlands)
Earth Space Solutions (Netherlands)
Sidney Cadot, SRON Netherlands Institute for Space Research (Netherlands)
Jigsaw BV (Netherlands)
Ilse Aben, SRON Netherlands Institute for Space Research (Netherlands)
Antje Ludewig, Royal Netherlands Meteorological Institute (Netherlands)
Jos Dingjan, Airbus Defence and Space Netherlands (Netherlands)
Stefan Persijn, VSL (Netherlands)
Ruud Hoogeveen, SRON Netherlands Institute for Space Research (Netherlands)

Published in SPIE Proceedings Vol. 10000:
Sensors, Systems, and Next-Generation Satellites XX
Roland Meynart; Steven P. Neeck; Toshiyoshi Kimura, Editor(s)

© SPIE. Terms of Use
Back to Top