 |
| Titel |
Smoke aerosol and its radiative effects during extreme fire event over Central Russia in summer 2010 |
| VerfasserIn |
N. Chubarova, Ye. Nezval', I. Sviridenkov, A. Smirnov, I. Slutsker |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1867-1381
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Measurement Techniques ; 5, no. 3 ; Nr. 5, no. 3 (2012-03-09), S.557-568 |
| Datensatznummer |
250002629
|
| Publikation (Nr.) |
 copernicus.org/amt-5-557-2012.pdf |
|
|
|
|
|
| Zusammenfassung |
| Different microphysical, optical and radiative properties of aerosol were
analyzed during the severe fires in summer 2010 over Central Russia using
ground measurements at two AERONET sites in Moscow (Meteorological
Observatory of Moscow State University – MSU MO) and Zvenigorod (Moscow
Region) and radiative measurements at the MSU MO. Volume aerosol size
distribution in smoke conditions had a bimodal character with the significant
prevalence of fine mode particles, for which effective radius was shifted to
higher values (reff-fine = 0.24 μm against approximately
0.15 μm in typical conditions). For smoke aerosol, the imaginary part of refractive index (REFI)
in the visible spectral region was lower than that for typical aerosol (REFIλ =675 nm = 0.006
against REFIλ =675 nm = 0.01), while single scattering
albedo (SSA) was significantly higher (SSAλ =675 nm = 0.95 against SSAλ =675 nm ~ 0.9).
Extremely high aerosol optical thickness at 500 nm (AOT500) was observed on
6–8 August reaching the absolute maximum on 7 August
in Moscow (AOT500 = 6.4) and at Zvenigorod (AOT500 = 5.9). A dramatic
attenuation of solar irradiance at ground was also recorded. Maximum
irradiance loss had reached 64% for global shortwave irradiance, 91%
for UV radiation 300–380 nm, and 97% for erythemally-weighted UV
irradiance at relatively high solar elevation 47°. Significant spectral
dependence in attenuation of solar irradiance in smoky conditions was mainly
explained by higher AOT and smaller SSA in UV (0.8–0.9) compared with SSA in
the visible region of spectrum. The assessments of radiative forcing effect
(RFE) at the TOA indicated a significant cooling of the smoky atmosphere.
Instant RFE reached −167 Wm−2 at AOT500 = 6.4, climatological RFE
calculated with August 2010 monthly mean AOT was about −65 Wm−2,
compared with −20 Wm−2 for typical aerosol according to the 10 yr
period of measurements in Moscow. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|