Articles | Volume 10, issue 11
Atmos. Meas. Tech., 10, 4209–4234, 2017

Special issue: The ACRIDICON-CHUVA campaign to study deep convective clouds...

Atmos. Meas. Tech., 10, 4209–4234, 2017

Research article 08 Nov 2017

Research article | 08 Nov 2017

The novel HALO mini-DOAS instrument: inferring trace gas concentrations from airborne UV/visible limb spectroscopy under all skies using the scaling method

Tilman Hüneke1, Oliver-Alex Aderhold1, Jannik Bounin1, Marcel Dorf1,a, Eric Gentry1,b, Katja Grossmann1,c, Jens-Uwe Grooß2, Peter Hoor3, Patrick Jöckel4, Mareike Kenntner1,d, Marvin Knapp1, Matthias Knecht1, Dominique Lörks1, Sabrina Ludmann1,e, Sigrun Matthes4, Rasmus Raecke1, Marcel Reichert1, Jannis Weimar1,f, Bodo Werner1, Andreas Zahn5, Helmut Ziereis4, and Klaus Pfeilsticker1 Tilman Hüneke et al.
  • 1Institut für Umweltphysik, University of Heidelberg, Heidelberg, Germany
  • 2Forschungszentrum Jülich, Institute of Energy and Climate Research – Stratosphere (IEK-7), Jülich, Germany
  • 3Institut für Physik der Atmosphäre, University of Mainz, Mainz, Germany
  • 4Deutsches Zentrum für Luft- und Raumfahrt, Institut für die Physik der Atmosphäre, Oberpfaffenhofen, Germany
  • 5Karlsruhe Institute of Technology (KIT), Institute for Meteorology and Climate Research, Karlsruhe, Germany
  • anow at: Max-Planck-Institute for Chemistry, Mainz, Germany
  • bnow at: Department of Astronomy and Astrophysics, University of California Santa Cruz, Santa Cruz, California, USA
  • cnow at: Joint Institute For Regional Earth System Science and Engineering (JIFRESSE), University of California Los Angeles, Los Angeles, California, USA
  • dnow at: Deutsches Zentrum für Luft- und Raumfahrt, Institut für die Physik der Atmosphäre, Oberpfaffenhofen, Germany
  • enow at: IFEU – Institut für Energie- und Umweltforschung Heidelberg GmbH, Heidelberg, Germany
  • fnow at: Physikalisches Institut, University of Heidelberg, Heidelberg, Germany

Abstract. We report on a novel six-channel optical spectrometer (further on called mini-DOAS instrument) for airborne nadir and limb measurements of atmospheric trace gases, liquid and solid water, and spectral radiances in the UV/vis and NIR spectral ranges. The spectrometer was developed for measurements from aboard the German High-Altitude and Long-Range (HALO) research aircraft during dedicated research missions. Here we report on the relevant instrumental details and the novel scaling method used to infer the mixing ratios of UV/vis absorbing trace gases from their absorption measured in limb geometry. The uncertainties of the scaling method are assessed in more detail than before for sample measurements of NO2 and BrO. Some first results are reported along with complementary measurements and comparisons with model predictions for a selected HALO research flight from Cape Town to Antarctica, which was performed during the research mission ESMVal on 13 September 2012.

Short summary
This paper describes a novel instrument for the aircraft-borne remote sensing of trace gases and liquid and solid water. Until recently, such measurements could only be evaluated under clear-sky conditions. We present a characterization and error assessment of the novel "scaling method", which allows for the retrieval of absolute trace gas concentrations under all sky conditions, significantly expanding the applicability of such measurements to study atmospheric photochemistry.