DOAS measurement from the Global Hawk during the NASA-ATTREX project
Final Report Abstract
Within the present project, a novel mini-DOAS instrument was assembled and successfully deployed on the Global Hawk in support of the NASA ATTREX missions (https://www.nasa.gov/centers/ames/events/2013/attrex.html). Within the NASA ATTREX project, three research campaigns were performed including 15 research flights of the Global Hawk, which flew into the tropical tropopause layer of the eastern and western Pacific (in late 2011, early 2013 and 2014). During all ATTREX missions the mini-DOAS instrument performed well, so that the collected data could be processed for the detection of the essential absorbers in the UV/vis/nearIR spectral range (e.g., O2, O3, O4, NO2, BrO, gaseous H2O and ice) expected in the TTL. All of this work was done in close cooperation with Prof. Jochen Stutz at the University of California, Los Angeles (UCLA), USA. Considerable progress has been made in the following major areas: (1) The retrieval mixing ratios (or absolute concentrations) of the targeted species under all (clear and cloudy) skies from UV/vis/nearIR skylight monitored in limb direction. Noteworthy to be reminded of here is that the interpretation of UV/vis/nearIR limb observations is rather challenging since (the a priori unconstrained) multiple scattering of skylight due to the presence of varying amounts of aerosols and clouds complicates the calculations of realistic photon path length distributions necessary to calculate absolute concentrations (molecules/cm3) from measured slant column amounts. Therefore, two novel retrieval methods, i.e. the scaling method designed for the interpretation of measurements in UV/visible spectral range, and a full spectral fit method for the interpretation of the measurements in the nearIR spectral range were developed and tested within the project. (2) From the concentration of O3, NO2, and BrO, the adopted photochemistry of ozone, NOx/NOy and of reactive bromine was tested, and inorganic bromine (Bryinorg) was inferred for the TTL. Furthermore, from the combination of our inferred Bryinorg with the simultaneous measurements of all relevant organic brominated source gases, for the first time novel information on the relative influx of CH3Br, the halons, very short-lived species (VSLS) and Bryinorg into the lowermost tropical stratosphere could be inferred. This aspect is rather exciting since TTL composition largely determines the composition of the whole stratosphere. In addition, the PhD thesis of Lisa Scalone addressed the first retrieval of the optical thickness and ice water content for TTL cirrus clouds using a full spectral fit in the nearIR spectral range. Even though her study primarily addressed the feasibility of such an approach, the obtained results are exciting in that the understanding of UV/vis/nearIR spectra provide the most direct approach to elucidate the short-wave forcing of the TTL cirrus, known to be an important ingredient for the global climate. Finally, the results obtained within the present project also served to validate the agreements made under international Protocol of Montreal 1987 and its amendments. Hence the results obtained during the present project are also reported in the upcoming ‘Assessment of Stratospheric Ozone’, published by the World Meteorological Organization/United Nation Environmental Programme (WMO/UNEP), later in 2018.
Publications
- Atmospheric test of the J(BrONO2)/k(BrO+NO2) ratio: Implications for total stratospheric Bry and bromine-mediated ozone loss, Atmos. Chem. Phys., 13, 6263 - 6274
Kreycy, S.K., C.C.-P. Camy-Peyret, M.P.C. Chipperfield, M.D. Dorf, W.F. Feng, R.H. Hossaini, L.K. Kritten, B.W. Werner, and K. Pfeilsticker
(See online at https://doi.org/10.5194/acp-13-6263-2013) - The NASA Airborne Tropical TRopopause EXperiment (ATTREX). Sparc Newsletters, 41, 15 - 24, July, 2013
Jensen Eric J., Leonhard Pister, David E. Jordan, David W Fahey, Paul A. Newman, Troy Thornberry, Andrew Rollins, Glenn S. Diskin, T. Paul Bui, Matthew McGill, Dennis Hlavka, R. Paul Lawson, Ru- Shan Gao, Peter Pilewskie, James Elkins, Eric Hintsa, Fred Moore, Michael J. Mahoney, Elliot Atlas, Jochen Stutz, Klaus Pfeilsticker, Steven C. Wofsy, Stephanie Evan, Karen H. Rosenlof
(See online at https://doi.org/10.1175/BAMS-D-14-00263.1) - Constraining the N2O5 UV absorption cross-section from spectroscopic trace gas measurements in the tropical mid-stratosphere, Atmos. Chem. Phys. 14, 9555 9566
Kritten, L., Butz, A., Chippefield, M. P., Dorf, M., Dhomse, S., Hossaini, R., Oelhaf, H., Prados-Roman, C., Wetzel, G., and Pfeilsticker, K.
(See online at https://doi.org/10.5194/acp-14-9555-2014) - Convective transport of very-short-lived bromo-carbons to the stratosphere, Atmos. Chem. Phys., 14, 57815792
Liang, Q., Atlas, E., Blake, D., Dorf, M., Pfeilsticker, K., and Schauffler, S.
(See online at https://doi.org/10.5194/acp-14-5781-2014) - The NASA Airborne Tropical TRopopause EXperiment (ATTREX): High-Altitude Aircraft Measurements in the Tropical Western Paci_c, Bull. American Met. Soc. 12/2015
Jensen E. J., L. Pfister, D. E. Jordan, T. V. Bui, R. Ueyama, H. B. Singh, T. Thornberry, A. W. Rollins, Ru- Shan Gao, D. W. Fahey, K. H. Rosenlof, J. W. Elkins, G. S. Diskin, J. P. DiGangi, R. P. Lawson, S. Woods, E. L. Atlas, M. A. NavarroRodriguez, S. C. Wofsy, J. Pittman, C. G. Bardeen, O. B. Toon, B. C. Kindel, P. A. Newman, M. J. McGill, D. L. Hlavka, L. R. Lait, M. R. Schoeberl, J. W. Bergman, H. B. Selkirk, M. J. Alexander, J.-E. Kim, B. H. Lim, J. Stutz, and K. Pfeilsticker
(See online at https://dx.doi.org/10.1175/BAMS-D-14-00263) - Transition operator calculation with the Green's dyadic technique for electromagnetic scattering: a numerical approach using the Dyson equation, Journal Quant. Spectr. and Radiative Transfer, 162, 77- 88
Tricoli, U., P. Vochezer, and K. Pfeilsticker
(See online at https://doi.org/10.1016/j.jqsrt.2015.04.006) - A multi-model intercomparison of halogenated very short-lived substances (TransCom-VSLS): linking oceanic emissions and tropospheric transport for a reconciled estimate of the stratospheric source gas injection of bromine, Atmos. Chem. Phys., 16, 9163-9187
Hossaini, R., Patra, P. K., Leeson, A. A., Krysztofiak, G., Abraham, N. L., Andrews,S. J., Archibald, A. T., Aschmann, J., Atlas, E. L., Belikov, D. A., Bönisch, H., Carpenter, L. J., Dhomse, S., Dorf, M., Engel, A., Feng, W., Fuhlbrügge, S., Griffiths, P. T., Harris, N. R. P., Hommel, R., Keber, T., Krüger, K., Lennartz, S. T., Maksyutov, S., Mantle, H., Mills, G. P., Miller, B., Montzka, S. A., Moore, F., Navarro, M. A., Oram, D. E., Pfeilsticker, K. Pyle, J. A., Quack, B., Robinson, A. D., Saikawa, E., Saiz-Lopez, A., Sala, S., Sinnhuber, B.-M., Taguchi, S., Tegtmeier, S., Lidster, R. T., Wilson, C., and Ziska, F
(See online at https://doi.org/10.5194/acp-16-9163-2016) - A New Differential Optical Absorption Spectroscopy Instrument to Study Atmospheric Chemistry from a High-Altitude Unmanned Aircraft, Atmos. Meas. Tech., 10, 1017-1042
Stutz, J., Werner, B., Spolaor, M., Scalone, L., Festa, J., Tsai, C., Cheung, R., Colosimo, Tricoli, U., Raecke, R., Hossaini, R., Chipperfield, Feng, W., Gao, R.-S., Hintsa, Elkins, Moore, Daube, B., Pittman, J., Wofsy, S., and Pfeilsticker, K.
(See online at https://doi.org/10.5194/amt-10-1017-2017) - Probing the subtropical lowermost stratosphere and the tropical upper troposphere and tropopause layer for inorganic bromine, Atmos. Chem. Phys., 17, 1161-1186
Werner, B., Stutz, J., Spolaor, M., Scalone, L., Raecke, R., Festa, J., Colosimo, S. F., Cheung, R., Tsai, C., Hossaini, R., Chipperfield, M. P., Taverna, G. S., Feng, W., Elkins, J. W., Fahey, D. W., Gao, R.-S., Hintsa, E. J., Thornberry, T. D., Moore, F. L., Navarro, M. A., Atlas, E., Daube, B. C., Pittman, J., Wofsy, S., and Pfeilsticker, K.
(See online at https://doi.org/10.5194/acp-17-1161-2017) - The novel HALO mini- DOAS instrument: inferring trace gas concentrations from airborne UV/visible limb spectroscopy under all skies using the scaling method, Atmos. Meas. Tech., 10, 4209 - 4234
Hüneke, T., Aderhold, O.-A., Bounin, J., Dorf, M., Gentry, E., Grossmann, K., Groß, J.-U., Hoor, P., Jöckel, P., Kenntner, M., Knapp, M., Knecht, M., Lörks, D., Ludmann, S., Matthes, S., Raecke, R., Reichert, M., Weimar, J., Werner, B., Zahn, A., Ziereis, H., and Pfeilsticker, K.
(See online at https://doi.org/10.5194/amt-10-4209-2017)