Improved retrieval of SO2 plume height from TROPOMI using an iterative Covariance-Based Retrieval Algorithm
-
Published:2022-08-24
Issue:16
Volume:15
Page:4801-4817
-
ISSN:1867-8548
-
Container-title:Atmospheric Measurement Techniques
-
language:en
-
Short-container-title:Atmos. Meas. Tech.
Author:
Theys Nicolas, Lerot ChristopheORCID, Brenot HuguesORCID, van Gent JeroenORCID, De Smedt IsabelleORCID, Clarisse Lieven, Burton MikeORCID, Varnam Matthew, Hayer Catherine, Esse BenjaminORCID, Van Roozendael Michel
Abstract
Abstract. Knowledge of sulfur dioxide layer height (SO2 LH) is important to
understand volcanic eruption processes, the climate impact of SO2
emissions and to mitigate volcanic risk for civil aviation. However, the
estimation of SO2 LH from ground-based instruments is challenging in
particular for rapidly evolving and sustained eruptions. Satellite
wide-swath nadir observations have the advantage to cover large-scale plumes
and the potential to provide key information on SO2 LH. In the
ultraviolet, SO2 LH retrievals leverage the fact that, for large
SO2 columns, the light path and its associated air mass factor (AMF)
depends on the SO2 absorption (and therefore on the vertical
distribution of SO2), and SO2 LH information can be obtained from
the analysis of measured back-scattered radiances coupled with radiative
transfer simulations. However, existing algorithms are mainly sensitive to
SO2 LH for SO2 vertical columns of at least 20 DU. Here we develop
a new SO2 LH algorithm and apply it to observations from the high-spatial-resolution TROPOspheric Monitoring Instrument (TROPOMI). It is based
on an SO2 optical depth look-up table and an iterative approach. The
strength of this scheme lies in the fact that it is a Covariance-Based
Retrieval Algorithm (COBRA; Theys et al., 2021). This means that the
SO2-free contribution of the measured optical depth is treated in an
optimal way, resulting in an improvement of the SO2 LH sensitivity to
SO2 columns as low as 5 DU, with a precision better than 2 km. We
demonstrate the value of this new data through a number of examples and
comparison with satellite plume height estimates (from IASI and CALIOP), and
back-trajectory analyses. The comparisons indicate an SO2 LH accuracy
of 1–2 km, except for some difficult observation conditions, in particular
for optically thick ash plumes or partially SO2-filled scenes.
Publisher
Copernicus GmbH
Subject
Atmospheric Science
Reference52 articles.
1. Aliwell, S. R., Van Roozendael, M., Johnston, P. V., Richter, A., Wagner, T., Arlander, D. W., Burrows, J. P., Fish, D. J., Jones, R. L., Tørnkvist, K. K., Lambert, J.-C., Pfeilsticker, K., and Pundt, I.: Analysis for
BrO in zenith-sky spectra: An intercomparison exercise for analysis
improvement, J. Geophys.
Res., 107, ACH 10-1–ACH 10-20, https://doi.org/10.1029/2001JD000329, 2002. 2. Beirle, S., Sihler, H., and Wagner, T.: Linearisation of the effects of spectral shift and stretch in DOAS analysis, Atmos. Meas. Tech., 6, 661–675, https://doi.org/10.5194/amt-6-661-2013, 2013. 3. Bogumil, K., Orphal, J., Homann, T., Voigt, S., Spietz, P., Fleischmann, O.,
Vogel, A., Hartmann, M., Bovensmann, H., Frerick, J., and Burrows, J. P.:
Measurements of molecular absorption spectra with the SCIAMACHY Pre-Flight
Model: instrument characterization and reference data for atmospheric
remote-sensing in the 230–2380 nm region, J. Photoch.
Photobio. A, 157, 167–184, 2003. 4. Brenot, H., Theys, N., Clarisse, L., van Geffen, J., van Gent, J., Van Roozendael, M., van der A, R., Hurtmans, D., Coheur, P.-F., Clerbaux, C., Valks, P., Hedelt, P., Prata, F., Rasson, O., Sievers, K., and Zehner, C.: Support to Aviation Control Service (SACS): an online service for near-real-time satellite monitoring of volcanic plumes, Nat. Hazards Earth Syst. Sci., 14, 1099–1123, https://doi.org/10.5194/nhess-14-1099-2014, 2014. 5. Brenot, H., Theys, N., Clarisse, L., van Gent, J., Hurtmans, D. R., Vandenbussche, S., Papagiannopoulos, N., Mona, L., Virtanen, T., Uppstu, A., Sofiev, M., Bugliaro, L., Vázquez-Navarro, M., Hedelt, P., Parks, M. M., Barsotti, S., Coltelli, M., Moreland, W., Scollo, S., Salerno, G., Arnold-Arias, D., Hirtl, M., Peltonen, T., Lahtinen, J., Sievers, K., Lipok, F., Rüfenacht, R., Haefele, A., Hervo, M., Wagenaar, S., Som de Cerff, W., de Laat, J., Apituley, A., Stammes, P., Laffineur, Q., Delcloo, A., Lennart, R., Rokitansky, C.-H., Vargas, A., Kerschbaum, M., Resch, C., Zopp, R., Plu, M., Peuch, V.-H., Van Roozendael, M., and Wotawa, G.: EUNADICS-AV early warning system dedicated to supporting aviation in the case of a crisis from natural airborne hazards and radionuclide clouds, Nat. Hazards Earth Syst. Sci., 21, 3367–3405, https://doi.org/10.5194/nhess-21-3367-2021, 2021.
Cited by
4 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|