 |
| Titel |
Evaluation of MAX-DOAS aerosol retrievals by coincident observations using CRDS, lidar, and sky radiometer inTsukuba, Japan |
| VerfasserIn |
H. Irie, T. Nakayama, A. Shimizu, A. Yamazaki, T. Nagai, A. Uchiyama, Y. Zaizen, S. Kagamitani, Y. Matsumi |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1867-1381
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Measurement Techniques ; 8, no. 7 ; Nr. 8, no. 7 (2015-07-16), S.2775-2788 |
| Datensatznummer |
250116479
|
| Publikation (Nr.) |
 copernicus.org/amt-8-2775-2015.pdf |
|
|
|
|
|
| Zusammenfassung |
| Coincident aerosol observations of multi-axis differential optical
absorption spectroscopy (MAX-DOAS), cavity ring-down spectroscopy (CRDS),
lidar, and sky radiometer were conducted in Tsukuba, Japan, on 5–18 October
2010. MAX-DOAS aerosol retrieval (for aerosol extinction coefficient and
aerosol optical depth at 476 nm) was evaluated from the viewpoint of the
need for a correction factor for oxygen collision complexes (O4 or
O2–O2) absorption. The present study strongly supports this need,
as systematic residuals at relatively high elevation angles
(20 and 30°) were evident in MAX-DOAS
profile retrievals conducted without the correction. However, adopting a
single number for the correction factor (fO4 = 1.25) for all of the
elevation angles led to systematic overestimation of near-surface aerosol
extinction coefficients, as reported in the literature. To achieve agreement
with all three observations, we limited the set of elevation angles to ≤10° and adopted an elevation-angle-dependent correction
factor for practical profile retrievals with scattered light observations by
a ground-based MAX-DOAS. With these modifications, we expect to minimize the
possible effects of temperature-dependent O4 absorption cross section
and uncertainty in DOAS fit on an aerosol profile retrieval, although more
efforts are encouraged to quantitatively identify a physical explanation for
the need of a correction factor. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|