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| Titel |
Year-round retrievals of trace gases in the Arctic using the Extended-range Atmospheric Emitted Radiance Interferometer |
| VerfasserIn |
Z. Mariani, K. Strong, M. Palm, R. Lindenmaier, C. Adams, X. Zhao, V. Savastiouk, C. T. McElroy, F. Goutail, J. R. Drummond |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1867-1381
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Measurement Techniques ; 6, no. 6 ; Nr. 6, no. 6 (2013-06-14), S.1549-1565 |
| Datensatznummer |
250017911
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| Publikation (Nr.) |
 copernicus.org/amt-6-1549-2013.pdf |
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| Zusammenfassung |
| The Extended-range Atmospheric Emitted Radiance Interferometer (E-AERI) was
installed at the Polar Environment Atmospheric Research Laboratory (PEARL)
at Eureka, Nunavut, Canada in October 2008. Spectra from the E-AERI provide
information about the radiative balance and budgets of trace gases in the
Canadian high Arctic. Measurements are taken every 7 min year-round,
including polar night when the solar-viewing spectrometers at PEARL are not
operated. This allows E-AERI measurements to fill the gap in the PEARL
dataset during the four months of polar night. Measurements were taken
year-round in 2008–2009 at the PEARL Ridge Lab, which is 610 m a.s.l. (above
sea-level), and from 2011 onwards at the Zero-Altitude PEARL Auxiliary Lab
(0PAL), which is at sea level 15 km from the Ridge Lab. Total columns of
O3, CO, CH4, and N2O have been retrieved using a modified
version of the SFIT2 retrieval algorithm adapted for emission spectra. This
provides the first ground-based nighttime measurements of these species at
Eureka. Changes in the total columns driven by photochemistry and dynamics
are observed. Analyses of E-AERI retrievals indicate accurate spectral fits
(root-mean-square residuals consistent with noise) and a 10–15%
uncertainty in the total column, depending on the trace gas. O3
comparisons between the E-AERI and a Bruker IFS 125HR Fourier transform
infrared (FTIR) spectrometer, three Brewer spectrophotometers, two
UV-visible ground-based spectrometers, and a System D'Analyse par
Observations Zenithales (SAOZ) at PEARL are made from 2008–2009 and for
2011. 125HR CO, CH4, and N2O columns are also compared with the
E-AERI measurements. Mean relative differences between the E-AERI and the
other spectrometers are 1–10% (14% is for the un-smoothed profiles), which are less than
the E-AERI's total column uncertainties. The E-AERI O3 and CO
measurements are well correlated with the other spectrometers (r > 0.92
with the 125HR). The 24 h diurnal cycle and 365-day
seasonal cycle of CO are observed and their amplitudes are quantified by the
E-AERI (6–12 and 46%, respectively). The seasonal variability of
H2O has an impact on the retrievals, leading to larger uncertainties in
the summer months. Despite increased water vapour at the lower-altitude site
0PAL, measurements at 0PAL are consistent with measurements at PEARL. |
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