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Impact of wild forest fires in Eastern Europe on aerosol composition and particle optical properties

Zieliński T., Petelski T., Strzałkowska A., Pakszys P., Makuch P.

Oceanologia

2016

No. 58 (1)

13--24

In this paper the authors discuss the changes of aerosol optical depth (AOD) in the region of eastern Europe and the Baltic Sea due to wild fire episodes which occurred in the area of Belarus and Ukraine in 2002. The authors discuss how the biomass burning aerosols were advected over the Baltic area and changed the composition of aerosol ensemble for a period of several summer weeks. The air pressure situation and slow wind speeds also facilitated the development of such conditions. As a consequence very high AOD levels were recorded, by an order of 3–4 higher versus normal conditions and they significantly increased the annual averages. On particular days of August 2002 the AOD values reached a level of over 0.7. On these days fine particles fully dominated the entire ensemble of aerosol particles. They were either sulfates or smoke particles. Such situation was unique over a period of many years and it had its serious consequences for the region and especially for the Baltic Sea.

Validation of SeaWiFS and MODIS Aqua/Terra aerosol products in coastal regions of European marginal seas

Mélin F., Zibordi G., Carlund T., Holben B. N., Stefan S.

Oceanologia

2013

No. 55 (1)

27-51

The aerosol products associated with the ocean colour missions SeaWiFS and MODIS (both Aqua and Terra) are assessed with AERONET field measurements collected in four European marginal seas for which fairly large uncertainties in ocean colour in-water products have been documented: the northern Adriatic, the Baltic, Black and North Seas. On average, more than 500 match-ups are found for each basin and satellite mission, showing an overall consistency of validation statistics across the three missions. The median absolute relative difference between satellite and field values of aerosol optical thickness ?a at 443 nm varies from 12% to 15% for the three missions at the northern Adriatic and Black Sea sites, and from 13% to 26% for the Baltic and North Sea sites. It is in the interval 16-31% for the near-infrared band. The spectral shape of ?ais well reproduced with a median bias of the Ängström exponent varying between -15% and +14%, which represents a clear improvement with respect to previous versions of the atmospheric correction scheme. These results show that the uncertainty associated with ?a in the considered coastal waters of the European marginal seas is comparable to global validation statistics.

Studies of aerosols advected to coastal areas with the use of remote techniques

Zieliński T., Petelski T., Makuch P., Strzałkowska A., Ponczkowska A., Markowicz K., Chourdakis G., Georgoussis G., Kratzer S

Acta Geophysica

2012

Vol. 60, no. 5

1359-1385

This paper presents the results of the studies of aerosol optical properties measured using lidars and sun photometers. We describe two case studies of the combined measurements made in two coastal zones in Crete in 2006 and in Rozewie on the Baltic Sea in 2009. The combination of lidar and sun photometer measurements provides comprehensive information on both the total aerosol optical thickness in the entire atmosphere as well as the vertical structure of aerosol optical properties. Combination of such information with air mass back-trajectories and data collected at stations located on the route of air masses provides complete picture of the aerosol variations in the study area both vertically and horizontally. We show that such combined studies are especially important in the coastal areas where depending on air mass advection directions and altitudes the influence of fine or coarse mode (in this case possibly sea-salt) particles on the vertical structure of aerosol optical properties is an important issue to consider.