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Investigation results of a coarse and accumulation mode of aerosol properties above the Baltic Sea are reported. A most important role in the direct aerosol effect on climate have aerosols from the group of coarse and accumulation mode particles. Overseas in the atmosphere, there is a lot of aerosols from the fine fraction but their impact is not so important as coarse and accumulation mode particles. Sea spray emission from the sea surface takes place over a wide range of aerosol particle size distribution, it is also large in size range which are studying in this work (Lewis and Schwartz, 2004). The discussed range is most important in view of atmospheric optical properties, smaller particles do not have such an influence on scattering as particles from range 0.5–2 µm. The research was performed with a multiwavelength lidar. Due to the application of special software, the aerosol particle size distributions were retrieved from the lidar returns. That provided an opportunity to determine the profiles of the aerosol effective radius. We showed that the aerosol properties depend mainly on the direction of the air mass advection and the wind speed. The impact of the Baltic Sea on the aerosol size distribution is huge in the case of the advection from the open sea. Moreover, the aerosol effective radiuses in the whole boundary layer are much larger in the case of strong than for light wind. Our results suggest that the aerosol flux and the aerosol particle size distribution should be related to the wind speed in the emission function.

The Poland-AOD aerosol research network was established in 2011 to improve aerosol–climate interaction knowledge and provide a real-time and historical, comprehensive, and quantitative database for the aerosol optical properties distribution over Poland. The network consists of research institutions and private owners operating 10 measurement stations and an organization responsible for aerosol model transport simulations. Poland-AOD collaboration provides observations of spectral aerosol optical depth (AOD), Ångstrom Exponent (AE), incoming shortwave (SW) and longwave (LW) radiation fluxes, vertical profiles of aerosol optical properties and surface aerosol scattering and absorption coefficient, as well as microphysical particle properties. Based on the radiative transfer model (RTM), the aerosol radiative forcing (ARF) and the heating rate are simulated. In addition, results from GEM-AQ and WRF-Chem models (e.g., aerosol mass mixing ratio and optical properties for several particle chemical components), and HYSPLIT back-trajectories are used to interpret the results of observation and to describe the 3D aerosol optical properties distribution. Results of Poland-AOD research indicate progressive improvement of air quality and at mospheric turbidity during the last decade. The AOD was reduced by about 0.02/10 yr (at 550 nm), which corresponds to positive trends in ARF. The estimated clear-sky ARF trend is 0.34 W/m2/10 yr and 0.68 W/m2/10 yr, respectively, at TOA and at Earth’s surface. Therefore, reduction in aerosol load observed in Poland can significantly contribute to climate warming.

The mesoscale circulation along the west shore of Spitsbergen is largely controlled by the difference in temperature between the glaciers and surface sea temperatures. We describe how the mesoscale effect influences the atmospheric circulation patterns. The conducted research was based on reanalysis data, model data, and atmospheric measurements; wind data from different sources and scales were compared and analysed. We discuss the situations wherein the mesoscale effect can be identified by analysing the wind direction or its velocity. This study shows the role of the mesoscale effect on the wind in the Svalbard region. Different situations according to the atmospheric patterns taken from a catalogue of 21 circulation types for each day created for Svalbard are analysed and compared with cases of land-sea breeze type circulation for the 20-year period between 1994 and 2013. It is proved that even if it is not possible to distinguish this mesoscale effect based on the difference between local and large-scale wind directions, this factor can be observed by studying the wind speeds. It is claimed that as long as there are glaciers on Spitsbergen, there will be a mesoscale land-sea breeze type circulation controlled by the difference in air temperature over land and water.

This paper presents the results of a comparison of basic meteorological parameters in two Arctic fjords situated on the west coast of Spitsbergen, the main island of the Svalbard archipelago. Air temperature, wind speed and direction, humidity and cloud cover from the period 2005 to 2016 are described and compared with previous (from 1975) analyses of meteorological conditions in the investigated region. Such a choice of dates coincides with the time the GAME project measurements were carried out. The main goal of this study was to compare meteorological conditions in two fjords: Hornsund and Kongsfjorden, during the time of rapid climate changes. The results are collated with research results available in literature from previous years. We discovered that in the investigated period the climate of the Hornsund region is more oceanic than in Kongsfjorden. The stable level of the difference in climate elements is manifested and is evident mainly through greater amplitudes in air temperatures in Kongsfjorden, and in stronger winds in Hornsund.

This paper presents the results of Aerosol Optical Depth (AOD) studies which took place in Ny-Ålesund in the spring of 2014 during the iAREA campaign. The measurements were taken using Microtops II hand-held sunphotometers along the Kongsfjorden, on a path leading from the research village to the fjord opening. Local breeze circulation was observed during the measurement campaign which resulted in an evident increase of AOD along the measurement profile towards the open sea. Using the observed AOD, changes over the open sea have been calculated and the location of the breeze front has been determined.

We present results of measurements of aerosol physical properties conducted on board of r/v Oceania during two cruises to the Spitsbergen region in 2014 (AREX 2014) and 2015 (AREX 2015). Measurements of aerosol size distribution, aerosol scattering coefficient and black carbon concentrations were made in two different Spitsbergen fjords: Hornsund and Kongsfjorden. The aerosol size distribution was measured in the size range from 0.09 μm to 47 μm using two aerosol size distribution spectrometers and a standard condensation particle counter. For the scattering coefficient an integrating nephelometer was used. Black carbon concentration was measured by an aethalometer. Temporal variabilities in physical properties of aerosol observed during the AREX 2014 and AREX 2015 campaigns were much higher than the differences between both fjords. The basic factors influencing aerosol conditions were advection and local generation of marine aerosol. In 2015 an episode of smoke advection was observed in both fjords causing an increase in the mean black carbon concentration from 7–12 ng m−3 to about 60 ng m−3, and an aerosol scattering coefficient at 550 nm from 2–4 Mm−1 to 12–17 Mm−1. Moreover, under certain conditions statistically significant gradients in aerosol optical properties were observed along the fjord axis reflecting an impact of mountains surrounding the fjords.

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.

The results of studies of the vertical gradient of aerosol concentration measurements made during cruises of r/v ‘Oceania’ between 2008 and 2012 are presented. Using the results from those experiments, sea spray emission fluxes were calculated for all particles of sizes in the range from 0.5 μm to 8 μm, as well as for particles of sizes from fifteen channels of 0.5 μm width. The information obtained was further used to calculate the Sea Salt Generation Function (SSGF) for the Baltic Sea depending on the wind speed and the aerosol size distribution.

During the summers of 2011 and 2012, two scientific cruises were carried out over the Arctic Ocean aiming at the determination of the aerosol chemical composition in this pristine environment. First, mass spectrometry was applied to study the concentration and gas/particle partitioning of polycyclic aromatic hydrocarbons (PAHs) and n-alkanes. Experimental and modelled data of phase partitioning were compared: results demonstrated an equilibrium between gas and particle phase for PAHs, while n-alkanes showed a particle-oriented partitioning, due to the local marine origin of them, confirmed by the extremely low value of their carbon preference index. Moreover, the inorganic and organic ions (carboxylic acids and amines) concentrations, together with those of elemental carbon (EC) and organic matter (OM), were analyzed: 63% of aerosol was composed of ionic compounds (>90% from sea-salt) and the OM content was very high (30.5%; close to 29.0% of Cl−) in agreement with n-alkanes’ marine signature. Furthermore, the amines’ (dimethylamine, trimethylamine, diethylamine) concentrations were 3.98 ± 1.21, 1.70 ± 0.82, and 1.06 ± 0.56 p.p.t.v., respectively, fully in keeping with concentration values used in the CLOUD (Cosmics Leaving OUtdoor Droplet)-chamber experiments to simulate the ambient nucleation rate in a H2SO4-DMA-H2O system, showing the amines’ importance in polar regions to promote new particle formation. Finally, high resolution mass spectrometry was applied to determine trace elements, including Rare Earth Elements (REEs), highlighting the dominant natural versus anthropic inputs for trace metals (e.g., Fe, Mn, Ti vs. As, Cd, Ni) and possible signatures of such anthropic activity.

New particle formation and growth were observed at a coastal site (Preila station, Lithuania) during 1997 and 2000-2002. The total amountof data analysed covers 291 one-day periods, 45 (15%) of which were long-term, new particle formation days. Short-term nucleationevents (from a few minutes to one hour) and long-term events (from one to eight hours) were identified. The mean particlegrowth rate, condensation sink and condensable vapour source rate during nucleation events were 3.9 nm h-1, 1.45 × 10-3 cm-3 s-1 and 7.5 × 104 cm-3 s-1 respectively.The average formation rate J10 was 0.4 cm-3 s-1. The nucleation events were accompaniedmainly by air masses transported from the north (43%) and north-west (19%). Meteorological parameters and trace gas (O3, SO2,NO2) concentrations were also analysed. It was found that nucleation events are related to high levels of solar radiation.

This paper presents the results of measurements of aerosol optical properties which were made between 2006 and 2008 within the framework of various international projects in different locations such as Spitsbergen, northern Norway and Crete. The investigations were made under different baric topography conditions and in various seasons of the year which facilitated the investigations of spatial and temporal dependencies between upper troposphere mass state and spectral variations of aerosol properties. The results of aerosol optical depth (AOD) measurements showed significant episodes during which jet stream events (300 hPa surface) over the Arctic were present. The mean spectral characteristics of AOD from “before” and “after” the event differ by 0.14 versus the “during” phase of the episode. The macrometeorological relative topography charts shown also the relationships between the 500 hPa, close sea-level pressure SLP (1,000 hPa) charts surfaces and the attenuation caused by aerosol scattering and absorption in vertical profiles during the afternoon hours.

Fluxes of radiation, sensible and latent heat, and fluxes of heat and salt within the upper layer of the ocean were calculated on the basis of measurements carried out in the area of the Norwegian-Atlantic and West Spitsbergen Currents during summer 2000. The sea surface radiation balance was calculated from direct measurements of downward and upward short-wave (solar) radiation, the net radiation fluxes and sea surface temperature. The daily doses of radiation energy reaching and leaving the sea surface were also estimated. To calculate the vertical heat fluxes in the atmospheric boundary layer the bulk parameterisation method was used. In most cases, the calculated heat fluxes were rather low, the average sensible heat flux was c. 10 W m-2, and the latent heat flux about one order of magnitude higher; this is what could be expected in summer. Salt fluxes to the air in the process of aerosol production are very small and can be neglected. In summer the highest quantities of heat and salt are exchanged during mixing with surrounding waters. According to our measurements, Atlantic Water on its northward course from about 70oN to 79oN loses about 100 TW of heat and 900 × 103 kg of salt. We thought it could be interesting to find out what happens to them. Some preliminary results of our investigation are presented here.

The paper presents the findings of experiments to determine marine aerosol emission from the coastal zone. A relation between aerosol flux and wave energy dissipation was found. The emission fluxes calculated for the distribution of aerosol concentration are proportional to the dissipation of wave energy to the power of 3/4. The calculations were carried out using the experimental data obtained during the TABEX and BAEX experiments.