Smoke aerosol and its radiative effects during extreme fire event over Central Russia in summer 2010
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 r...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2012-03-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | http://www.atmos-meas-tech.net/5/557/2012/amt-5-557-2012.pdf |
| _version_ | 1818612277608185856 |
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| author | N. Chubarova Ye. Nezval' I. Sviridenkov A. Smirnov I. Slutsker |
| author_facet | N. Chubarova Ye. Nezval' I. Sviridenkov A. Smirnov I. Slutsker |
| author_sort | N. Chubarova |
| collection | DOAJ |
| description | 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 (<i>r</i><aub>eff-fine</aub> = 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 (REFI<sub>&lambda; =675 nm</sub> = 0.006 against REFI<sub>&lambda; =675 nm</sub> = 0.01), while single scattering albedo (SSA) was significantly higher (SSA<sub>&lambda; =675 nm</sub> = 0.95 against SSA<sub>&lambda; =675 nm</sub> ~ 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<sup>−2</sup> at AOT500 = 6.4, climatological RFE calculated with August 2010 monthly mean AOT was about −65 Wm<sup>−2</sup>, compared with −20 Wm<sup>−2</sup> for typical aerosol according to the 10 yr period of measurements in Moscow. |
| first_indexed | 2024-12-16T15:43:40Z |
| format | Article |
| id | doaj.art-15e5e564baee407a91a1c33b4f7f7a1b |
| institution | Directory Open Access Journal |
| issn | 1867-1381 1867-8548 |
| language | English |
| last_indexed | 2024-12-16T15:43:40Z |
| publishDate | 2012-03-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Measurement Techniques |
| spelling | doaj.art-15e5e564baee407a91a1c33b4f7f7a1b2022-12-21T22:25:52ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482012-03-015355756810.5194/amt-5-557-2012Smoke aerosol and its radiative effects during extreme fire event over Central Russia in summer 2010N. ChubarovaYe. Nezval'I. SviridenkovA. SmirnovI. SlutskerDifferent 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 (<i>r</i><aub>eff-fine</aub> = 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 (REFI<sub>&lambda; =675 nm</sub> = 0.006 against REFI<sub>&lambda; =675 nm</sub> = 0.01), while single scattering albedo (SSA) was significantly higher (SSA<sub>&lambda; =675 nm</sub> = 0.95 against SSA<sub>&lambda; =675 nm</sub> ~ 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<sup>−2</sup> at AOT500 = 6.4, climatological RFE calculated with August 2010 monthly mean AOT was about −65 Wm<sup>−2</sup>, compared with −20 Wm<sup>−2</sup> for typical aerosol according to the 10 yr period of measurements in Moscow.http://www.atmos-meas-tech.net/5/557/2012/amt-5-557-2012.pdf |
| spellingShingle | N. Chubarova Ye. Nezval' I. Sviridenkov A. Smirnov I. Slutsker Smoke aerosol and its radiative effects during extreme fire event over Central Russia in summer 2010 Atmospheric Measurement Techniques |
| title | Smoke aerosol and its radiative effects during extreme fire event over Central Russia in summer 2010 |
| title_full | Smoke aerosol and its radiative effects during extreme fire event over Central Russia in summer 2010 |
| title_fullStr | Smoke aerosol and its radiative effects during extreme fire event over Central Russia in summer 2010 |
| title_full_unstemmed | Smoke aerosol and its radiative effects during extreme fire event over Central Russia in summer 2010 |
| title_short | Smoke aerosol and its radiative effects during extreme fire event over Central Russia in summer 2010 |
| title_sort | smoke aerosol and its radiative effects during extreme fire event over central russia in summer 2010 |
| url | http://www.atmos-meas-tech.net/5/557/2012/amt-5-557-2012.pdf |
| work_keys_str_mv | AT nchubarova smokeaerosolanditsradiativeeffectsduringextremefireeventovercentralrussiainsummer2010 AT yenezval smokeaerosolanditsradiativeeffectsduringextremefireeventovercentralrussiainsummer2010 AT isviridenkov smokeaerosolanditsradiativeeffectsduringextremefireeventovercentralrussiainsummer2010 AT asmirnov smokeaerosolanditsradiativeeffectsduringextremefireeventovercentralrussiainsummer2010 AT islutsker smokeaerosolanditsradiativeeffectsduringextremefireeventovercentralrussiainsummer2010 |