Aerosol optical depth over the Arctic: a comparison of ECHAM-HAM and TM5 with ground-based, satellite and reanalysis data

Abstract. We compare ground-based measurements of aerosol optical depth and Ångström parameter at six Arctic stations in the period 2001–2006 with the results from two global aerosol dynamics and transport models, ECHAM-HAM and TM5. Satellite measurements from MODIS and the MACC reanalysis product are used to examine the spatial distribution and the seasonality of these parameters and to compare them with model results. We find that both models provide a good reproduction of the Ångström parameter but significantly underestimate the observed AOD values. We also explore the effects of changes in emissions, model resolution and the parametrization of wet scavenging.

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Probing into the aging dynamics of biomass burning aerosol by using satellite measurements of aerosol optical depth and carbon monoxide

10.5194/acp-2016-797 ◽

2016 ◽

Author(s):

Igor B. Konovalov ◽

Matthias Beekmann ◽

Evgeny V. Berezin ◽

Paola Formenti ◽

Meinrat O. Andreae

Keyword(s):

Carbon Monoxide ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Biomass Burning ◽

Basis Set ◽

Carbonaceous Aerosol ◽

Oxidation Reactions ◽

Satellite Measurements ◽

Aerosol Dynamics ◽

Aerosol Aging

Abstract. Carbonaceous aerosol released into the atmosphere from open biomass burning (BB) is known to undergo considerable chemical and physical transformations (aging). However, there exists substantial controversy about the nature and observable effects of these transformations. A shortage of consistent observational evidence on BB aerosol aging processes in different environmental conditions and at various temporal scales hinders developing their adequate representations in chemistry transport models (CTMs). In this study, we obtain insights into the BB aerosol dynamics by using available satellite measurements of aerosol optical depth (AOD) and carbon monoxide (CO). The basic concept of our method is to consider AOD as a function of the BB aerosol "photochemical age" (that is, the time period characterizing the exposure of BB aerosol emissions to atmospheric oxidation reactions) predicted by means of model tracers. We evaluate the AOD enhancement ratio (ER) defined as the ratio of optical depth of actual BB aerosol with respect to that of a modeled aerosol tracer that is assumed to originate from the same fires as the real BB aerosol but is not affected by any aging processes. To limit possible effects of model transport errors, the AOD measurements are normalized to CO column amounts that are also retrieved from satellite measurements. The method is applied to the analysis of the meso- and synoptic-scale evolution of aerosol in smoke plumes from major wildfires that occurred in Siberia in summer 2012. AOD and CO retrievals from, respectively, MODIS and IASI measurements are used in combination with simulations performed with the CHIMERE CTM. The analysis indicates that aging processes strongly affected the evolution of BB aerosol in the situation considered, especially in dense plumes (with PM2.5 concentration exceeding 100 μg m−3). For such plumes, the ER is found to increase almost twofold on the scale of ~ 10 hours of the daytime evolution of aerosol (after a few first hours of the evolution that are not resolved in our analysis). The robustness of this finding is corroborated by sensitivity tests and Monte Carlo experiments. Furthermore, a simulation using the volatility basis set framework suggests that a large part of the increase in the ER can be explained by atmospheric processing of semi-volatile organic compounds. Our results are consistent with findings of a number of earlier studies reporting considerable underestimation of AOD by CTMs in which BB aerosol aging processes have either been disregarded or simulated in a highly simplified way. In general, this study demonstrates the feasibility of using satellite measurements of AOD in biomass burning plumes in combination with aerosol tracer simulations for the investigation of BB aerosol evolution and validation of BB aerosol aging schemes in atmospheric models.

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Relationship between cloud condensation nuclei (CCN) concentration and aerosol optical depth in the Arctic region

Atmospheric Environment ◽

10.1016/j.atmosenv.2021.118748 ◽

2021 ◽

pp. 118748

Author(s):

Seo H. Ahn ◽

Y.J. Yoon ◽

T.J. Choi ◽

J.Y. Lee ◽

Y.P. Kim ◽

...

Keyword(s):

Aerosol Optical Depth ◽

Optical Depth ◽

Cloud Condensation Nuclei ◽

Arctic Region ◽

The Arctic ◽

Condensation Nuclei ◽

The Arctic Region

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Shipboard sunphotometer measurements of aerosol optical depth spectra and columnar water vapor during ACE-2, and comparison with selected land, ship, aircraft, and satellite measurements

Tellus B ◽

10.3402/tellusb.v52i2.17122 ◽

2000 ◽

Vol 52 (2) ◽

pp. 594-619

Author(s):

John M. Livingstone ◽

Vladimir N. Kapustin ◽

Beat Schmid ◽

Philip B. Russel ◽

Patricia K. Quinn ◽

...

Keyword(s):

Water Vapor ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Satellite Measurements ◽

Columnar Water Vapor

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Estimated total emissions of trace gases from the Canberra Wildfires of 2003: a new method using satellite measurements of aerosol optical depth & the MOZART chemical transport model

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-5739-2010 ◽

2010 ◽

Vol 10 (12) ◽

pp. 5739-5748 ◽

Cited By ~ 13

Author(s):

C. Paton-Walsh ◽

L. K. Emmons ◽

S. R. Wilson

Keyword(s):

Carbon Monoxide ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Transport Model ◽

Chemical Transport ◽

New Method ◽

Chemical Transport Model ◽

Satellite Measurements ◽

Additional Tool ◽

Vegetation Fires

Abstract. In this paper we describe a new method for estimating trace gas emissions from large vegetation fires using satellite measurements of aerosol optical depth (AOD) at 550 nm, combined with an atmospheric chemical transport model. The method uses a threshold value to screen out normal levels of AOD that may be caused by raised dust, sea salt aerosols or diffuse smoke transported from distant fires. Using this method we infer an estimated total emission of 15±5 Tg of carbon monoxide, 0.05±0.02 Tg of hydrogen cyanide, 0.11±0.03 Tg of ammonia, 0.25±0.07 Tg of formaldehyde, 0.03±0.01 of acetylene, 0.10±0.03 Tg of ethylene, 0.03±0.01 Tg of ethane, 0.21±0.06 Tg of formic acid and 0.28±0.09 Tg of methanol released to the atmosphere from the Canberra fires of 2003. An assessment of the uncertainties in the new method is made and we show that our estimate agrees (within expected uncertainties) with estimates made using current conventional methods of multiplying together factors for the area burned, fuel load, the combustion efficiency and the emission factor for carbon monoxide. A simpler estimate derived directly from the satellite AOD measurements is also shown to be in agreement with conventional estimates, suggesting that the method may, under certain meteorological conditions, be applied without the complication of using a chemical transport model. The new method is suitable for estimating emissions from distinct large fire episodes and although it has some significant uncertainties, these are largely independent of the uncertainties inherent in conventional techniques. Thus we conclude that the new method is a useful additional tool for characterising emissions from vegetation fires.

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Interannual and seasonal variations in aerosol optical depth of the atmosphere in two regions of Spitsbergen Archipelago (2002–2018)

10.5194/amt-2020-83 ◽

2020 ◽

Author(s):

Dmitry M. Kabanov ◽

Christoph Ritter ◽

Sergey M. Sakerin

Keyword(s):

Aerosol Optical Depth ◽

Optical Depth ◽

Wave Spectrum ◽

Short Wave ◽

The Arctic ◽

Data Set ◽

Fine Mode ◽

European Arctic ◽

Highly Correlated ◽

Fine Mode Aerosol

Abstract. In this work hourly averaged sun photometer data from the sites Barentsburg and Ny-Ålesund, both located in Spitsbergen in the European Arctic, are compared. Our data set comprises the years 2011 to 2017. We found for more turbid periods (aerosol optical depth τ0.5 > 0.1) that typically Barentsburg is more polluted than Ny-Ålesund, especially in the short wave spectrum. However, the diurnal variation of AOD is highly correlated. Next, τ was divided into a fine and coarse mode. It was found that generally the fine mode aerosol optical depth dominates and also shows a larger interannual as inner annual variation. Tau fine τf is in fact larger in spring during the Arctic Haze period. Overall the aerosol optical depth seems to decrease, although this is not statistically significant.

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Supplementary material to "Probing into the aging dynamics of biomass burning aerosol by using satellite measurements of aerosol optical depth and carbon monoxide"

10.5194/acp-2016-797-supplement ◽

2016 ◽

Author(s):

Igor B. Konovalov ◽

Matthias Beekmann ◽

Evgeny V. Berezin ◽

Paola Formenti ◽

Meinrat O. Andreae

Keyword(s):

Carbon Monoxide ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Biomass Burning ◽

Satellite Measurements ◽

Biomass Burning Aerosol ◽

Supplementary Material

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A characterization of Arctic aerosols on the basis of aerosol optical depth and black carbon measurements

Elem Sci Anth ◽

10.12952/journal.elementa.000027 ◽

2014 ◽

Vol 2 ◽

Cited By ~ 40

Author(s):

R. S. Stone ◽

S. Sharma ◽

A. Herber ◽

K. Eleftheriadis ◽

D. W. Nelson

Keyword(s):

Black Carbon ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Atmospheric Aerosols ◽

Surface Radiation ◽

Radiation Budget ◽

The Arctic ◽

Carbonaceous Particles ◽

Surface Warming ◽

Soot Deposition

Abstract Aerosols, transported from distant source regions, influence the Arctic surface radiation budget. When deposited on snow and ice, carbonaceous particles can reduce the surface albedo, which accelerates melting, leading to a temperature-albedo feedback that amplifies Arctic warming. Black carbon (BC), in particular, has been implicated as a major warming agent at high latitudes. BC and co-emitted aerosols in the atmosphere, however, attenuate sunlight and radiatively cool the surface. Warming by soot deposition and cooling by atmospheric aerosols are referred to as “darkening” and “dimming” effects, respectively. In this study, climatologies of spectral aerosol optical depth AOD (2001–2011) and Equivalent BC (EBC) (1989–2011) from three Arctic observatories and from a number of aircraft campaigns are used to characterize Arctic aerosols. Since the 1980s, concentrations of BC in the Arctic have decreased by more than 50% at ground stations where in situ observations are made. AOD has increased slightly during the past decade, with variations attributed to changing emission inventories and source strengths of natural aerosols, including biomass smoke and volcanic aerosol, further influenced by deposition rates and airflow patterns.

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