 |
| Titel |
Mountain wave PSC dynamics and microphysics from ground-based lidar measurements and meteorological modeling |
| VerfasserIn |
J. Reichardt, A. Dörnbrack, S. Reichardt, P. Yang, T. J. McGee |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 4, no. 4 ; Nr. 4, no. 4 (2004-07-30), S.1149-1165 |
| Datensatznummer |
250001845
|
| Publikation (Nr.) |
 copernicus.org/acp-4-1149-2004.pdf |
|
|
|
|
|
| Zusammenfassung |
| The day-long observation of a polar stratospheric cloud (PSC) by
two co-located ground-based lidars at the Swedish research
facility Esrange (67.9° N, 21.1° E) on 16
January 1997 is analyzed in terms of PSC dynamics and
microphysics. Mesoscale modeling is utilized to simulate the
meteorological setting of the lidar measurements. Microphysical
properties of the PSC particles are retrieved by comparing the
measured particle depolarization ratio and the PSC-averaged lidar
ratio with theoretical optical data derived for different
particle shapes. In the morning, nitric acid trihydrate (NAT)
particles and then increasingly coexisting liquid ternary aerosol
(LTA) were detected as outflow from a mountain wave-induced ice
PSC upwind Esrange. The NAT PSC is in good agreement with
simulations for irregular-shaped particles with length-to-diameter
ratios between 0.75 and 1.25, maximum dimensions from 0.7 to
0.9 µm, and a number density from 8 to 12 cm-3 and the
coexisting LTA droplets had diameters from 0.7 to 0.9 µm, a
refractive index of 1.39 and a number density from 7 to
11 cm-3. The total amount of condensed HNO3 was in the
range of 8–12 ppbv. The data provide further observational
evidence that NAT forms via deposition nucleation on ice
particles as a number of recently published papers suggest. By
early afternoon the mountain-wave ice PSC expanded above the
lidar site. Its optical data indicate a decrease in minimum
particle size from 3 to 1.9 µm with time. Later on,
following the weakening of the mountain wave, wave-induced LTA
was observed only. Our study demonstrates that ground-based lidar
measurements of PSCs can be comprehensively interpreted if
combined with mesoscale meteorological data. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|