Development of a digital mobile solar tracker
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Published:2016-03-08
Issue:3
Volume:9
Page:963-972
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ISSN:1867-8548
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Container-title:Atmospheric Measurement Techniques
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language:en
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Short-container-title:Atmos. Meas. Tech.
Author:
Baidar Sunil, Kille Natalie, Ortega IvanORCID, Sinreich Roman, Thomson David, Hannigan James, Volkamer RainerORCID
Abstract
Abstract. We have constructed and deployed a fast digital solar tracker aboard a moving ground-based platform. The tracker consists of two rotating mirrors, a lens, an imaging camera, and a motion compensation system that provides the Euler angles of the mobile platform in real time. The tracker can be simultaneously coupled to UV–Vis and Fourier transform infrared spectrometers, making it a versatile tool to measure the absorption of trace gases using solar incoming radiation. The integrated system allows the tracker to operate autonomously while the mobile laboratory is in motion. Mobile direct sun differential optical absorption spectroscopy (mobile DS-DOAS) observations using this tracker were conducted during summer 2014 as part of the Front Range Air Pollution and Photochemistry Experiment (FRAPPE) in Colorado, USA. We demonstrate an angular precision of 0.052° (about 1/10 of the solar disk diameter) during research drives and verify this tracking precision from measurements of the center to limb darkening (CLD, the changing appearance of Fraunhofer lines) in the mobile DS-DOAS spectra. The high photon flux from direct sun observation enables measurements of nitrogen dioxide (NO2) slant columns with high temporal resolution and reveals spatial detail in the variations of NO2 vertical column densities (VCDs). The NO2 VCD from DS-DOAS is compared with a co-located MAX-DOAS instrument. Overall good agreement is observed amid a highly heterogeneous air mass.
Funder
Colorado Department of Public Health and Environment
Publisher
Copernicus GmbH
Subject
Atmospheric Science
Reference26 articles.
1. Baidar, S., Oetjen, H., Coburn, S., Dix, B., Ortega, I., Sinreich, R., and
Volkamer, R.: The CU Airborne MAX-DOAS instrument: vertical profiling of
aerosol extinction and trace gases, Atmos. Meas. Tech., 6, 719–739,
https://doi.org/10.5194/amt-6-719-2013, 2013a. 2. Baidar, S., Volkamer, R., Alvarez II, R. J., Brewer, W. A., Davies, F.,
Langford, A. O., Oetjen, H., Pearson, G., Senff, C. J., and Hardesty, R. M.:
Combining active and passive airborne remote sensing to quantify NO2
and Ox production near Bakersfield, CA, British Journal of Environment
and Climate Change, 3, 566–586, https://doi.org/10.9734/BJECC/2013/5740, 2013b. 3. Bertleff, M.: Camera based sun tracking system for mobile platforms, Masters
thesis, Karlsruhe Institute of Technology, Germany, 2014. 4. Bosch, H., Camy-Peyret, C., Chipperfield, M. P., Fitzenberger, R., Harder,
H., Platt, U., and Pfeilsticker, K.: Upper limits of stratospheric IO and
OIO inferred from center-to-limb-darkening-corrected balloon-borne solar
occultation visible spectra: Implications for total gaseous iodine and
stratospheric ozone, J. Geophys. Res.-Atmos., 108, 4455,
https://doi.org/10.1029/2002JD003078, 2003. 5. Butz, A.: Case studies of stratospheric nitrogen, chlorine and iodine
photochemistry based on balloon borne UV/Vis and IR absorption spectroscopy,
PhD dissertation, Ruperto Carola University of Heidelberg, Germany, 2006.
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