Dr. Michiel van Weele Profile

Dr. Michiel van Weele

at Koninklijk Nederlands Meteorologisch Instituut

SPIE Involvement:

Author

Proceedings Article | 20 October 2006 Paper

On the use of quantitative diurnal cloud information for the calculation of daily UV dose maps over Europe

M. van Weele, R. van der A

Proceedings Volume 6362, 63621A (2006) https://doi.org/10.1117/12.689936

KEYWORDS: Clouds, Ultraviolet radiation, Ozone, Satellites, UV optics, Commercial off the shelf technology, Aerosols, Climatology, Solids, Algorithm development

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Proceedings Article | 7 September 2006 Paper

TROPOMI and TROPI: UV/VIS/NIR/SWIR instruments

P. Levelt, G. H. van den Oord, M. Dobber, H. Eskes, M. van Weele, P. Veefkind, R. van Oss, I. Aben, R. Jongma, J. Landgraf, J. de Vries, H. Visser

Proceedings Volume 6296, 629619 (2006) https://doi.org/10.1117/12.680582

KEYWORDS: Short wave infrared radiation, Aerosols, Calibration, Ozone, Diffusers, Carbon monoxide, Near infrared, Sensors, Spectroscopy, Signal to noise ratio

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TROPOMI (Tropospheric Ozone-Monitoring Instrument) is a five-channel UV-VIS-NIR-SWIR non-scanning nadir viewing imaging spectrometer that combines a wide swath (114°) with high spatial resolution (10 × 10 km² ). The instrument heritage consists of GOME on ERS-2, SCIAMACHY on Envisat and, especially, OMI on EOS-Aura. TROPOMI has even smaller ground pixels than OMI-Aura but still exceeds OMI's signal-to-noise performance. These improvements optimize the possibility to retrieve tropospheric trace gases. In addition, the SWIR capabilities of TROPOMI are far better than SCIAMACHY's both in terms of spatial resolution and signal to noise performance. TROPOMI is part of the TRAQ payload, a mission proposed in response to ESA's EOEP call. The TRAQ mission will fly in a non-sun synchronous drifting orbit at about 720 km altitude providing nearly global coverage. TROPOMI measures in the UV-visible wavelength region (270-490 nm), in a near-infrared channel (NIR) in the 710-775 nm range and has a shortwave infrared channel (SWIR) near 2.3 μm. The wide swath angle, in combination with the drifting orbit, allows measuring a location up to 5 times a day at 1.5-hour intervals. The spectral resolution is about 0.45 nm for UVVIS- NIR and 0.25 nm for SWIR. Radiometric calibration will be maintained via solar irradiance measurements using various diffusers. The instrument will carry on-board calibration sources like LEDs and a white light source. Innovative aspects include the use of improved detectors in order to improve the radiation hardness and the spatial sampling capabilities. Column densities of trace gases (NO₂, O₃, SO₂ and HCHO) will be derived using primarily the Differential Optical Absorption Spectroscopy (DOAS) method. The NIR channel serves to obtain information on clouds and the aerosol height distribution that is needed for tropospheric retrievals. A trade-off study will be conducted whether the SWIR channel, included to determine column densities of CO and CH₄, will be incorporated in TROPOMI or in the Fourier Transform Spectrometer SIFTI on TRAQ. The TROPI instrument is similar to the complete TROPOMI instrument (UV-VIS-NIR-SWIR) and is proposed for the CAMEO initiative, as described for the U.S. NRC Decadal Study on Earth Science and Applications from Space. CAMEO also uses a non-synchronous drifting orbit, but at a higher altitude (around 1500 km). The TROPI instrument design is a modification of the TROPOMI design to achieve identical coverage and ground pixel sizes from a higher altitude. In this paper capabilities of TROPOMI and TROPI are discussed with emphasis on the UV-VIS-NIR channels as the TROPOMI SWIR channel is described in a separate contribution [5].

Proceedings Article | 1 November 2005 Paper

Space-based surface UV monitoring for Europe using SCIAMACHY and MSG

Michiel van Weele, Ronald van der A, Jos van Geffen, Rob Roebeling

Proceedings Volume 5979, 59791K (2005) https://doi.org/10.1117/12.626516

KEYWORDS: Ultraviolet radiation, Clouds, Ozone, Satellites, Aerosols, UV optics, Meteorology, Data modeling, Climatology, Solar radiation

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Proceedings Article | 21 October 2005 Paper

Spectrograph dedicated to measuring tropospheric trace gas constituents from space

Johan de Vries, Erik Laan, Alex Deutz, Isabel Escudero-Sanz, Henk Bokhove, Jan Hoegee, Ilse Aben, Rienk Jongma, Jochen Landgraf, Otto Hasekamp, Sander Houweling, Michiel van Weele, Roeland van Oss, Gijsbertus van den Oord, Pieternel Levelt

Proceedings Volume 5978, 59780O (2005) https://doi.org/10.1117/12.627008

KEYWORDS: Aerosols, Clouds, Sensors, Short wave infrared radiation, Satellites, Carbon monoxide, Climatology, Ozone, Aerospace engineering, Gases

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