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An integrated morphological and chemical analysis of Arctic aerosols was undertaken for Icelandic dust and Svalbard aerosols to be compared by scanning electron microscopy coupled with EDS microanalysis (SEM–EDS) via imaging and chemical analysis techniques. Results of the characterization of the particles from both surface sediments and suspended dust from desert areas in Iceland confirmed that volcanic glass is an excellent marker of Icelandic dust origin. Classification diagrams of particle chemical composition clearly distinguished the volcanic glass particles from the local surface sediments at Hornsund, Svalbard. In the same diagrams, a few particles were found in the aerosols from Hornsund which were morphologically and chemically similar to the Icelandic volcanic glass particles. Such properties, in principle, cannot be considered exclusive to volcanic glass. However, since Iceland is the largest and the most active source of long-range transported dust in the northern European high latitudes, and air mass trajectories reaching Hornsund did, actually, pass Iceland before the aerosol collection in the period under consideration, these particles likely originated in Iceland. On the other hand, the comparison with local and Icelandic sediments revealed the presence in the aerosols from Hornsund of particle types that cannot be attributed to either local or Icelandic dust. This observation highlights the possibility of extending and validating the application of the proposed geochemical criterion to different dust sources across the Arctic and the sub-Arctic, provided a consistent geochemical databank of representative dust sources from these areas is arranged. [ABSTRACT FROM AUTHOR]

The 2010 eruption of Eyjafjallajökull produced volcanic ash that was mostly deposited to the south and east of the volcano, with the thickest deposits closest to the eruption vents. For months following the eruption there were numerous reports of resuspended volcanic ash made by weather observers on the ground.A saltation sensor (SENSIT) and an optical particle counter (OPC) located on the southern side of Eyjafjallajökull measured posteruptive particulate matter (PM) saltation and suspension events, some of which were also observable by satellite imagery. During the autumn/winter following the eruption, visible satellite images and the SENSIT show thatPMmeasured by the OPC was only detected when winds had a northerly component, making the source on the slopes of Eyjafjallajökull. During the largest observed events, particles .10 mm were suspended but measured in extremely low concentrations (,1 particle per centimeter cubed). The saltation measurements, however, show high concentrations of particles .100 mm in size during these events. During the largest events, winds were at least 5ms21 with a relative humidity, 70%. Ground conditions in Iceland change quickly from unfavorable to favorable for the suspension of particles. It is hypothesized that this is due to the porosity of the surface material allowing water to filter through quickly as well as the fast drying time of surface material. The high moisture content of the atmosphere and the ground do not appear to be a deterrent for large PM events to occur in Iceland. [ABSTRACT FROM AUTHOR]

Iceland is a volcanic island in the North Atlantic Ocean with maritime climate. In spite of moist climate, large areas are with limited vegetation cover where >40% of Iceland is classified with considerable to very severe erosion and 21% of Iceland is volcanic sandy deserts. Not only do natural emissions from these sources influenced by strong winds affect regional air quality in Iceland (“Reykjavik haze”), but dust particles are transported over the Atlantic ocean and Arctic Ocean >1000 km at times. The aim of this paper is to place Icelandic dust production area into international perspective, present long-term frequency of dust storm events in northeast Iceland, and estimate dust aerosol concentrations during reported dust events. Meteorological observations with dust presence codes and related visibility were used to identify the frequency and the long-term changes in dust production in northeast Iceland. There were annually 16.4 days on average with reported dust observations on weather stations within the northeastern erosion area, indicating extreme dust plume activity and erosion within the northeastern deserts, even though the area is covered with snow during the major part of winter. During the 2000s the highest occurrence of dust events in six decades was reported. We have measured saltation and Aeolian transport during dust/volcanic ash storms in Iceland, which give some of the most intense wind erosion events ever measured. Icelandic dust affects the ecosystems over much of Iceland and causes regional haze. It is likely to affect the ecosystems of the oceans around Iceland, and it brings dust that lowers the albedo of the Icelandic glaciers, increasing melt-off due to global warming. The study indicates that Icelandic dust may contribute to the Arctic air pollution. Implications:Long-term records of meteorological dust observations from Northeast Iceland indicate the frequency of dust events from Icelandic deserts. The research involves a 60-year period and provides a unique perspective of the dust aerosol production from natural sources in the sub-Arctic Iceland. The amounts are staggering, and with this paper, it is clear that Icelandic dust sources need to be considered among major global dust sources. This paper presents the dust events directly affecting the air quality in the Arctic region. [ABSTRACT FROM AUTHOR]

Particulate matter mass concentrations and size fractions of PM1, PM2.5, PM4, PM10, and PM15 measured in transversal horizontal profile of two dust storms in southwestern Iceland are presented. Images from a camera network were used to estimate the visibility and spatial extent of measured dust events. Numerical simulations were used to calculate the total dust flux from the sources as 180,000 and 280,000 tons for each storm. The mean PM15 concentrations inside of the dust plumes varied from 10 to 1600 µg∙m-3 (PM10 = 7 to 583 µg∙m-3). The mean PM1 concentrations were 97-241 µg∙m-3 with a maximum of 261 µg∙m-3 for the first storm. The PM1/PM2.5 ratios of >0.9 and PM1/PM10 ratios of 0.34-0.63 show that suspension of volcanic materials in Iceland causes air pollution with extremely high PM1 concentrations, similar to polluted urban areas in Europe or Asia. Icelandic volcanic dust consists of a higher proportion of submicron particles compared to crustal dust. Both dust storms occurred in relatively densely inhabited areas of Iceland. First results on size partitioning of Icelandic dust presented here should challenge health authorities to enhance research in relation to dust and shows the need for public dust warning systems. [ABSTRACT FROM AUTHOR]

• Many parts of Iceland are affected by the severe aeolian erosion. • Dendrochronological analyses of dwarf shrubs provided reliable data on rates and timing of aeolian erosion. • Erosion rates (post-1990′s) ranged from 1.0 cm yr−1 in the 1970 s to 4.4–5.4 cm yr−1. • Reconstructed erosion rates in NE Iceland compared well to observations of dusty conditions (from the 1970′s to the present) • Increased erosion rates of small erosional escarpments coincide with dust storm activity. Iceland is known for having strong aeolian erosion events, as evidenced by erosional escarpments on the soil surface; these are known locally as rofabards. The aim of the study was to estimate aeolian erosion rates at two research plots affected by severe erosion, using anatomic features of the roots of Arctic, woody, dwarf shrubs. Ours is the first study to utilize dendrochronological analyses of exposed roots of dwarf willows (Salix herbacea L.) as an indicator of aeolian erosion. When dwarf shrub roots are exposed to the atmosphere by erosion, cell sizes are reduced by >50 %, with maximum changes in individual plants exceeding 150–200 %. We detected the erosion signal by analyzing changes in cell-size and width of growth rings in the roots. Using this relationship, were able to estimate erosion rates (the retreat of escarpments) since the 1970s for the study area. During the 1970s and 1980s, erosion rates were fairly constant, with retreat ranging from 1.0 to 2.5 cm yr−1. Rapid increases in erosion rates were observed after the late 1990s, occasionally as much as 4.4–5.4 cm yr−1. Increased aeolian erosion rates may be linked to continuous heavy grazing by sheep and climate change, as this period coincides with increased numbers of hot and warm, and dusty days. Our results indicate that dendrochronological methods can be highly useful in determining past geomorphic activity, due to modern environmental changes observed in the Arctic. The methods employed here can be applied even in treeless areas. [ABSTRACT FROM AUTHOR]

Abstract: Long-term records of meteorological dust observations from Northeast Iceland were analysed and frequency of dust events from Icelandic deserts calculated. A total of 1033 dust days were reported during the period 1949–2011 with an annual mean of 16.4 dust days year−1, placing the area among the dustiest areas in the world. The most active decades were the 2000s, 1990s and 1950s. Monthly dust event frequency is bimodal with primary and secondary maxima in June and September. A total of 14 severe dust storms (visibility < 500 m) occurred during the period. Median dust event concentration was calculated as 106 μg m−3 from the visibility observations. The frequency and severity of dust events depend on Sea Level Pressure (SLP) oscillation which controls the southerly winds in NE Iceland. The availability of fine sediments susceptible to dust production in outwash plains controlled by the flow rate of glacial river is also important. Volcanic ash from eruptions in 2010 and 2011 barely affected the dust event frequency in NE Iceland. Icelandic dust may be substantial source for large scale air pollution in the Arctic. [Copyright &y& Elsevier]

In April and May 2010 the Icelandic volcano Eyjafjallajökull experienced an explosive eruption that led to substantial ashfall across the central-southern parts of the island. The resulting ash deposits covered Eyjafjallajökull, Mýrdalsjökull and parts of Vatnajökull ice caps. In order to quantify the influence of these deposits on albedo, we analyzed albedo evolution across Eyjafjallajökull and Mýrdalsjökull ice caps over the period 2001–2016 using the MOD10A1 and MCD43A3 data products of the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor onboard the Terra and Aqua satellites. A geostatistical model with a daily temporal resolution was used to delineate areas on the ice caps that show distinct ash cover-related albedo reductions over the post-eruption period. Results suggest that despite an overall decrease of the ash cover-related albedo reductions with time, noticeable albedo reductions persist on both, Eyjafjallajökull and Mýrdalsjökull over the entire post-eruption period. These reductions show means of 0.19 ± 0.11 and 0.17 ± 0.10, respectively, and occur most prominently during the summer seasons. Persistent albedo reductions are in agreement with and limited to areas of higher ash deposition during the volcanic eruption such as the southern parts of Eyjafjallajökull and Mýrdalsjökull ice caps. In addition, redistribution of Eyjafjallajökull ash deposited on the lowlands in southern Iceland contributed to dust storm events in the years after the eruption and caused additional albedo reductions. • Persistent albedo reduction across southern Eyjafjallajökull and Mýrdalsjökull • Persistent albedo reduction in areas of highest ashfall especially at convex terrains • Ash influence-related albedo reduction across all other areas diminishes over time [ABSTRACT FROM AUTHOR]

Saharan dust samples collected in Europe compose almost totally from fine-grained silty material. Reported grain size values are generally in the range of 2 to 20-30 µm, however, episodically the grain size of transported Saharan dust material can be significantly larger. And now, these giant mineral dust particles are standing in the focal point of recent investigations. Dust material collected in Iceland from the deposited material of an unusual Sahara dust event (April 2014) was analysed by automated static image analysis technique completed with Raman spectroscopy. More than hundred thousand individual particles were granulometrically characterized, and we were able to identify quartz particles larger than 100 micrometres. Transport of giant particles from the Sahara towards the Arctic can be regarded as extremely rare events, previous studies did not mention similar episodes.Support of the National Research, Development and Innovation Office NKFIH KH130337 (for G. Varga) is gratefully acknowledged. [ABSTRACT FROM AUTHOR]