Geochemical fingerprints and North-African dust sources: results from a multisite network of aerosol deposition in the south-western Europe

2021 ◽  
Author(s):  
Jorge Pey ◽  
Juan Cruz Larrasoaña ◽  
Jesús Reyes ◽  
Noemí Pérez ◽  
José Carlos Cerro ◽  
...  
Keyword(s):  
Atmospheric Deposition ◽  
Source Apportionment ◽  
Saharan Dust ◽  
Dust Particles ◽  
Dust Deposition ◽  
North African ◽  
Desert Dust ◽  
African Dust ◽  
Dust Sources ◽  
The Impact

<p><strong>Abstract</strong></p><p>The DONAIRE network (Pey et al. 2020) monitors the phenomenology of geochemical, magnetic and mineralogical variations of bulk atmospheric deposition in the Iberian Peninsula- Balearic Island. In this work we focus on recent North African dust deposition with a double objective: 1) to characterize the main geochemical fingerprints with respect to other sources of pollution; 2) to perform a source apportionment study to identify different desert-dust source areas. We used one year of data (June 2016-July 2017) from 15 monitoring sites (regional and remote, urban, industrial, or agricultural). We focus here on the impact caused by the main 4 North African dust deposition events globally affected this network.</p><p>Our results evidence that dust deposition patterns are controlled by: i) the meteorological scenario behind dust transport, ii) the occurrence/absence of wet deposition, and iii) the local-to-regional nearby topography. In general, the largest dust-deposition events occur nearby mountain barriers during low-pressure systems approaching Iberia and NW Africa.</p><p>Moderate to intense dust deposition events are well characterized by their chemical composition. The Fe/Ti, Na/Al, K/Al or (Ca+Mg)/Fe ratios reveal a number of patterns across the network. For example, Fe/Ti ratio varies from around 10-13 during warm-season events to 22-35 during cold season episodes, potentially indicating different North-African dust sources.</p><p>The best source apportionment solution extracts 10 factor/sources, from which three are mineral in composition. Two of them are interpreted as different North African dust mixture-of-sources, whereas the third mineral factor corresponds to regional dust particles. The overall contribution of such desert-dust sources may explain up to 90% of total episodic deposition during the most intense events.</p><p>These results indicate that chemical fingerprinting could be used to infer the recent North African dust deposition history. Studies on lake and peatland sequences following a similar approach are in progress and preliminary data show they be used to trace Saharan dust during the Holocene and reconstruct its relationship with climate phases.</p><p> </p><p><strong>Reference</strong></p><p>Pey J., Larrasoaña J.C., Pérez N., Cerro J.C., Castillo S. <em>et al.</em> (2020). Phenomenology and geographical gradients of atmospheric deposition in southwestern Europe: results from a multi-site monitoring network. <em>Sci. Tot. Environ.</em>, 140745. https://doi.org/10.1016/j.scitotenv.2020.140745.</p><p> </p><p><strong>Acknowledgements</strong></p><p>POSAHPI (PID2019-108101RB-I00) and DONAIRE (CGL2015-68993-R) projects funded by Spanish Agencia Estatal de Investigación and FEDER Funds.</p>

scholarly journals Introduction to project DUNE, a DUst experiment in a low Nutrient, low chlorophyll Ecosystem

2014 ◽  
Vol 11 (2) ◽  
pp. 425-442 ◽  
Author(s):  
C. Guieu ◽  
F. Dulac ◽  
C. Ridame ◽  
P. Pondaven
Keyword(s):  
Atmospheric Deposition ◽  
Surface Waters ◽  
Wet Deposition ◽  
Initial Conditions ◽  
Sediment Traps ◽  
Saharan Dust ◽  
Dust Particles ◽  
Dust Deposition ◽  
Mesocosm Experiments ◽  
Atmospheric Inputs

Abstract. The main goal of project DUNE was to estimate the impact of atmospheric deposition on an oligotrophic ecosystem based on mesocosm experiments simulating strong atmospheric inputs of eolian mineral dust. Our mesocosm experiments aimed at being representative of real atmospheric deposition events onto the surface of oligotrophic marine waters and were an original attempt to consider the vertical dimension after atmospheric deposition at the sea surface. This introductory paper describes the objectives of DUNE and the implementation plan of a series of mesocosm experiments conducted in the Mediterranean Sea in 2008 and 2010 during which either wet or dry and a succession of two wet deposition fluxes of 10 g m−2 of Saharan dust have been simulated based on the production of dust analogs from erodible soils of a source region. After the presentation of the main biogeochemical initial conditions of the site at the time of each experiment, a general overview of the papers published in this special issue is presented. From laboratory results on the solubility of trace elements in dust to biogeochemical results from the mesocosm experiments and associated modeling, these papers describe how the strong simulated dust deposition events impacted the marine biogeochemistry. Those multidisciplinary results are bringing new insights into the role of atmospheric deposition on oligotrophic ecosystems and its impact on the carbon budget. The dissolved trace metals with crustal origin – Mn, Al and Fe – showed different behaviors as a function of time after the seeding. The increase in dissolved Mn and Al concentrations was attributed to dissolution processes. The observed decrease in dissolved Fe was due to scavenging on sinking dust particles and aggregates. When a second dust seeding followed, a dissolution of Fe from the dust particles was then observed due to the excess Fe binding ligand concentrations present at that time. Calcium nitrate and sulfate were formed in the dust analog for wet deposition following evapocondensation with acids for simulating cloud processing by polluted air masses under anthropogenic influence. Using a number of particulate tracers that were followed in the water column and in the sediment traps, it was shown that the dust composition evolves after seeding by total dissolution of these salts. This provided a large source of new dissolved inorganic nitrogen (DIN) in the surface waters. In spite of this dissolution, the typical inter-elemental ratios in the particulate matter, such as Ti / Al or Ba / Al, are not affected during the dust settling, confirming their values as proxies of lithogenic fluxes or of productivity in sediment traps. DUNE experiments have clearly shown the potential for Saharan wet deposition to modify the in situ concentrations of dissolved elements of biogeochemical interest such as Fe and also P and N. Indeed, wet deposition yielded a transient increase in dissolved inorganic phosphorus (DIP) followed by a very rapid return to initial conditions or no return to initial conditions when a second dust seeding followed. By transiently increasing DIP and DIN concentrations in P- and N-starved surface waters of the Mediterranean Sea, wet deposition of Saharan dust can likely relieve the potential P and/or N limitation of biological activity; this has been directly quantified in terms of biological response. Wet deposition of dust strongly stimulated primary production and phytoplanktonic biomass during several days. Small phytoplankton (< 3 μm) was more stimulated after the first dust addition, whereas the larger size class (> 3 μm) significantly increased after the second one, indicating that larger-sized cells need further nutrient supply in order to be able to adjust their physiology and compete for resource acquisition and biomass increase. Among the microorganisms responding to the atmospheric inputs, diazotrophs were stimulated by both wet and dry atmospheric deposition, although N2 fixation was shown to be only responsible for a few percent of the induced new production. Dust deposition modified the bacterial community structure by selectively stimulating and inhibiting certain members of the bacterial community. The microbial food web dynamics were strongly impacted by dust deposition. The carbon budget indicates that the net heterotrophic character (i.e., ratio of net primary production to bacteria respiration < 1) of the tested waters remained (or was even increased) after simulated wet or dry deposition despite the significant stimulation of autotrophs after wet events. This indicates that the oligotrophic tested waters submitted to dust deposition are a net CO2 source. Nonetheless, the system was able to export organic material, half of it being associated with lithogenic particles through aggregation processes between lithogenic particles and organic matter. These observations support the "ballast" hypothesis and suggest that this "lithogenic carbon pump" could represent a major contribution of the global carbon export to deep waters in areas receiving high rates of atmospheric deposition. Furthermore, a theoretical microbial food web model showed that, all other things being equal, carbon, nitrogen and phosphorus stoichiometric mismatch along the food chain can have a substantial impact on the ecosystem response to nutrient inputs from dusts, with changes in the biomass of all biological compartments by a factor of ~ 2–4, and shifts from net autotrophy to net heterotrophy. Although the model was kept simple, it highlights the importance of stoichiometric constrains on the dynamics of microbial food webs.

scholarly journals Characteristics and Seasonal Variations of Atmospheric Deposition of Selected Elements in the Urban and Industrial Environment of Košice (Slovakia)

2021 ◽  
Vol 906 (1) ◽  
pp. 012100
Author(s):  
Jozef Hančul’ák ◽  
Ol’ga Šestinová ◽  
Lenka Findoráková
Keyword(s):  
Atmospheric Deposition ◽  
Detailed Analysis ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Water Soluble ◽  
Dust Particles ◽  
Winter Period ◽  
Emission Sources ◽  
Summer Period ◽  
The Impact

Abstract This study aims to evaluate the impact of local emission sources on the environmental load through a detailed analysis of the atmospheric deposition (AD). The main sources of pollution are neighbouring iron and steelworks and typical urban sources, such as the heating plant, transport, construction, etc. Total atmospheric deposition, i.e. both wet and dry ones, were sampled from eleven sampling sites that have been placed on the roofs above the height of the surrounding buildings at a distance of 1 to 16 kilometers from the main source of pollution in the urban, suburban and rural areas. The atmospheric deposition fluxes of selected elements (Fe, Al, Mn, Zn, Pb, Cu, Cr, Cd, As) were determined separately for “water-soluble” and “insoluble phase” (particulate matter - PM) as well as in terms of the heating season for summer and winter half-year. The results from 2009–2020 are introduced. The average Fe deposition at urban stations in Košice was 2-3 times higher, compared with other urban areas. The very high values of iron deposition (9,181) and manganese (348 mg.m-2.yr-1) were measured mainly at sites near the ironworks. The highest values of correlation coefficients were calculated by Pearson correlation analysis for the elements Fe, Mn and Cr but also for Al and PM. Higher values of correlation coefficients were calculated for the winter period. The monitored elements are bound to the insoluble component AD in the order of Fe, Al, Cr, Pb, Mn and As. Cadmium and zinc are preferably bound to the soluble phase for sites north of the ironworks. Significant differences for fluxes of AD of the most observed parameters were found between the summer and winter periods. In winter, higher values of AD were found for the elements Fe, Pb, Mn, Cr, and Cd. In the case of zinc and arsenic higher values were recorded in the summer period. The share of emission sources of iron and steelworks on the fluxes of iron at the urban sites in winter was more than doubled compared to the summer period. The smallest seasonal differences for all observed components were found at localities near the ironworks. Detailed analysis of AD showed that in addition to Fe, Mn, and Cr, the ironworks complex is also a source of dust particles, aluminum and other observed elements in descending order of lead, zinc, copper, arsenic and cadmium.

scholarly journals Impact of dust deposition on carbon budget: a tentative assessment from a mesocosm approach

2014 ◽  
Vol 11 (19) ◽  
pp. 5621-5635 ◽  
Author(s):  
C. Guieu ◽  
C. Ridame ◽  
E. Pulido-Villena ◽  
M. Bressac ◽  
K. Desboeufs ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Atmospheric Deposition ◽  
Mediterranean Sea ◽  
Particulate Organic Carbon ◽  
Dry Deposition ◽  
Wet Deposition ◽  
Carbon Budget ◽  
Net Primary Production ◽  
Saharan Dust ◽  
Dust Deposition

Abstract. By bringing new nutrients and particles to the surface ocean, atmospheric deposition impacts biogeochemical cycles. The extent to which those changes are modifying the carbon balance in oligotrophic environments such as the Mediterranean Sea that receives important Saharan dust fluxes is unknown. The DUNE (DUst experiment in a low Nutrient, low chlorophyll Ecosystem) project provides the first attempt to evaluate the changes induced in the carbon budget of a large body of oligotrophic waters after simulated Saharan dust wet or dry deposition events, allowing us to measure (1) the metabolic fluxes while the particles are sinking and (2) the particulate organic carbon export. Here we report the results for the three distinct artificial dust seeding experiments simulating wet or dry atmospheric deposition onto large mesocosms (52 m3) that were conducted in the oligotrophic waters of the Mediterranean Sea in the summers of 2008 and 2010. Although heterotrophic bacteria were found to be the key players in the response to dust deposition, net primary production increased about twice in case of simulated wet deposition (that includes anthropogenic nitrogen). The dust deposition did not produce a shift in the metabolic balance as the tested waters remained net heterotrophic (i.e., net primary production to bacteria respiration ratio <1) and in some cases the net heterotrophy was even enhanced by the dust deposition. The change induced by the dust addition on the total organic carbon pool inside the mesocosm over the 7 days of the experiments, was a carbon loss dominated by bacteria respiration that was at least 5–10 times higher than any other term involved in the budget. This loss of organic carbon from the system in all the experiments was particularly marked after the simulation of wet deposition. Changes in biomass were mostly due to an increase in phytoplankton biomass but when considering the whole particulate organic carbon pool it was dominated by the organic carbon aggregated to the lithogenic particles still in suspension in the mesocosm at the end of the experiment. Assuming that the budget is balanced, the dissolved organic carbon (DOC) pool was estimated by the difference between the total organic carbon and the particulate organic carbon (POC) pool. The partitioning between dissolved and particulate organic carbon was dominated by the dissolved pool with a DOC consumption over 7 days of ∼1 μmol C L−1 d−1 (dry deposition) to ∼2–5 μmol C L−1 d−1 (wet deposition). This consumption in the absence of any allochthonous inputs in the closed mesocosms meant a small <10% decrease of the initial DOC stock after a dry deposition but a ∼30–40% decrease of the initial DOC stock after wet deposition. After wet deposition, the tested waters, although dominated by heterotrophy, were still maintaining a net export (corrected from controls) of particulate organic carbon (0.5 g in 7 days) even in the absence of allochthonous carbon inputs. This tentative assessment of the changes in carbon budget induced by a strong dust deposition indicates that wet deposition by bringing new nutrients has higher impact than dry deposition in oligotrophic environments. In the western Mediterranean Sea, the mineral dust deposition is dominated by wet deposition and one perspective of this work is to extrapolate our numbers to time series of deposition during similar oligotrophic conditions to evaluate the overall impact on the carbon budget at the event and seasonal scale in the surface waters of the northwestern Mediterranean Sea. These estimated carbon budgets are also highlighting the key processes (i.e., bacterial respiration) that need to be considered for an integration of atmospheric deposition in marine biogeochemical modeling.

scholarly journals Contribution of the world's main dust source regions to the global cycle of desert dust

2021 ◽  
Author(s):  
Jasper F. Kok ◽  
Adeyemi A. Adebiyi ◽  
Samuel Albani ◽  
Yves Balkanski ◽  
Ramiro Checa-Garcia ◽  
...  
Keyword(s):  
Aerosol Optical Depth ◽  
Optical Depth ◽  
Biogeochemical Cycles ◽  
Deposition Flux ◽  
Dust Deposition ◽  
North African ◽  
Dust Source ◽  
Desert Dust ◽  
Source Regions ◽  
Dust Loading

Abstract. Even though desert dust is the most abundant aerosol by mass in Earth's atmosphere, the relative contributions of the world’s major dust source regions to the global dust cycle remain poorly constrained. This problem hinders accounting for the potentially large impact of regional differences in dust properties on clouds, the Earth's energy balance, and terrestrial and marine biogeochemical cycles. Here, we constrain the contribution of each of the world’s main dust source regions to the global dust cycle. We use an analytical framework that integrates an ensemble of global model simulations with observationally informed constraints on the dust size distribution, extinction efficiency, and regional dust aerosol optical depth. We obtain a data set that constrains the relative contribution of each of nine major source regions to size-resolved dust emission, atmospheric loading, optical depth, concentration, and deposition flux. We find that the 22–29 Tg (one standard error range) global loading of dust with geometric diameter up to 20 μm is partitioned as follows: North African source regions contribute ~50 % (11–15 Tg), Asian source regions contribute ~40 % (8–13 Tg), and North American and Southern Hemisphere regions contribute ~10 % (1.8–3.2 Tg). Current models might on average be overestimating the contribution of North African sources to atmospheric dust loading at ~65 %, while underestimating the contribution of Asian dust at ~30 %. However, both our results and current models could be affected by unquantified biases, such as due to errors in separating dust aerosol optical depth from that produced by other aerosol species in remote sensing retrievals in poorly observed desert regions. Our results further show that each source region's dust loading peaks in local spring and summer, which is partially driven by increased dust lifetime in those seasons. We also quantify the dust deposition flux to the Amazon rainforest to be ~10 Tg/year, which is a factor of 2–3 less than inferred from satellite data by previous work that likely overestimated dust deposition by underestimating the dust mass extinction efficiency. The data obtained in this paper can be used to obtain improved constraints on dust impacts on clouds, climate, biogeochemical cycles, and other parts of the Earth system.

scholarly journals Apparent dust size discrepancy in aerosol reanalysis in north African dust after long-range transport

2020 ◽  
Vol 20 (16) ◽  
pp. 10047-10062 ◽  
Author(s):  
Samantha J. Kramer ◽  
Claudia Alvarez ◽  
Anne E. Barkley ◽  
Peter R. Colarco ◽  
Lillian Custals ◽  
...  
Keyword(s):  
Aerosol Optical Depth ◽  
Long Range ◽  
Optical Depth ◽  
Dust Particles ◽  
Long Range Transport ◽  
North African ◽  
African Dust ◽  
Range Transport ◽  
Dust Mass ◽  
Mass Concentrations

Abstract. North African dust reaches the southeastern United States every summer. Size-resolved dust mass measurements taken in Miami, Florida, indicate that more than one-half of the surface dust mass concentrations reside in particles with geometric diameters less than 2.1 µm, while vertical profiles of micropulse lidar depolarization ratios show dust reaching above 4 km during pronounced events. These observations are compared to the representation of dust in the Modern-Era Retrospective analysis for Research and Applications, version 2 (MERRA-2) aerosol reanalysis and closely related Goddard Earth Observing System model version 5 (GEOS-5) Forward Processing (FP) aerosol product, both of which assimilate satellite-derived aerosol optical depths using a similar protocol and inputs. These capture the day-to-day variability in aerosol optical depth well, in a comparison to an independent sun-photometer-derived aerosol optical depth dataset. Most of the modeled dust mass resides in diameters between 2 and 6 µm, in contrast to the measurements. Model-specified mass extinction efficiencies equate light extinction with approximately 3 times as much aerosol mass, in this size range, compared to the measured dust sizes. GEOS-5 FP surface-layer sea salt mass concentrations greatly exceed observed values, despite realistic winds and relative humidities. In combination, these observations help explain why, despite realistic total aerosol optical depths, (1) free-tropospheric model volume extinction coefficients are lower than those retrieved from the micro-pulse lidar, suggesting too-low model dust loadings in the free troposphere, and (2) model dust mass concentrations near the surface can be higher than those measured. The modeled vertical distribution of dust, when captured, is reasonable. Large, aspherical particles exceeding the modeled dust sizes are also occasionally present, but dust particles with diameters exceeding 10 µm contribute little to the measured total dust mass concentrations after such long-range transport. Remaining uncertainties warrant a further integrated assessment to confirm this study's interpretations.

scholarly journals Optical characteristics of desert dust over the East Mediterranean during summer: a case study

2006 ◽  
Vol 24 (3) ◽  
pp. 807-821 ◽  
Author(s):  
D. Balis ◽  
V. Amiridis ◽  
S. Kazadzis ◽  
A. Papayannis ◽  
G. Tsaknakis ◽  
...  
Keyword(s):  
Saharan Dust ◽  
Dust Particles ◽  
Spatial Evolution ◽  
Northern Greece ◽  
Height Range ◽  
Desert Dust ◽  
Local Pollution ◽  
The North ◽  
Lidar Measurements ◽  
South Axis

Abstract. High aerosol optical depth (AOD) values, larger than 0.6, are systematically observed in the Ultraviolet (UV) region both by sunphotometers and lidar systems over Greece during summertime. To study in more detail the characteristics and the origin of these high AOD values, a campaign took place in Greece in the frame of the PHOENICS (Particles of Human Origin Extinguishing Natural solar radiation In Climate Systems) and EARLINET (European Aerosol Lidar Network) projects during August–September of 2003, which included simultaneous sunphotometric and lidar measurements at three sites covering the north-south axis of Greece: Thessaloniki, Athens and Finokalia, Crete. Several events with high AOD values have been observed over the measuring sites during the campaign period, many of them corresponding to Saharan dust. In this paper we focused on the event of 30 and 31 August 2003, when a dust layer in the height range of 2000-5000 m, progressively affected all three stations. This layer showed a complex behavior concerning its spatial evolution and allowed us to study the changes in the optical properties of the desert dust particles along their transport due to aging and mixing with other types of aerosol. The extinction-to-backscatter ratio determined on the 30 August 2003 at Thessaloniki was approximately 50 sr, characteristic for rather spherical mineral particles, and the measured color index of 0.4 was within the typical range of values for desert dust. Mixing of the desert dust with other sources of aerosols resulted the next day in overall smaller and less absorbing population of particles with a lidar ratio of 20 sr. Mixing of polluted air-masses originating from Northern Greece and Crete and Saharan dust result in very high aerosol backscatter values reaching 7 Mm-1 sr-1 over Finokalia. The Saharan dust observed over Athens followed a different spatial evolution and was not mixed with the boundary layer aerosols mainly originating from local pollution.

scholarly journals An automatic collector to monitor insoluble atmospheric deposition: application for mineral dust deposition

2015 ◽  
Vol 8 (7) ◽  
pp. 2801-2811 ◽  
Author(s):  
B. Laurent ◽  
R. Losno ◽  
S. Chevaillier ◽  
J. Vincent ◽  
P. Roullet ◽  
...  
Keyword(s):  
Atmospheric Deposition ◽  
Mineral Dust ◽  
Western Mediterranean ◽  
Saharan Dust ◽  
Dust Deposition ◽  
Air Masses ◽  
Mineral Deposition ◽  
Southern Mediterranean ◽  
Key Terms ◽  
Continuous Deposition

Abstract. Deposition is one of the key terms of the mineral dust cycle. However, dust deposition remains poorly constrained in transport models simulating the atmospheric dust cycle. This is mainly due to the limited number of relevant deposition measurements. This paper aims to present an automatic collector (CARAGA), specially developed to sample the total (dry and wet) atmospheric deposition of insoluble dust in remote areas. The autonomy of the CARAGA can range from 25 days to almost 1 year depending on the programmed sampling frequency (from 1 day to 2 weeks respectively). This collector is used to sample atmospheric deposition of Saharan dust on the Frioul islands in the Gulf of Lions in the Western Mediterranean. To quantify the mineral dust mass in deposition samples, a weighing and ignition protocol is applied. Almost 2 years of continuous deposition measurements performed on a weekly sampling basis on Frioul Island are presented and discussed with air mass trajectories and satellite observations of dust. Insoluble mineral deposition measured on Frioul Island was 2.45 g m−2 for February to December 2011 and 3.16 g m−2 for January to October 2012. Nine major mineral deposition events, measured during periods with significant MODIS aerosol optical depths, were associated with air masses coming from the southern Mediterranean Basin and North Africa.

Climatology of dust deposition in the Adriatic Sea and biological response of Rogoznica Lake (central Adriatic)

2021 ◽  
Author(s):  
Boris Mifka ◽  
Irena Ciglenečki ◽  
Maja Telišman Prtenjak
Keyword(s):  
North Africa ◽  
Adriatic Sea ◽  
Biological Response ◽  
Direct Consequence ◽  
Reanalysis Data ◽  
Dust Deposition ◽  
Dust Transport ◽  
Desert Dust ◽  
Dust Sources ◽  
Marine System

&lt;p&gt;Airborne desert dust is one of the most abundant aerosols and an important factor in climate&lt;br&gt;change. After deposition in the sea, mineral dust acts as the nutrient. In this study, the climatology&lt;br&gt;of desert dust deposition in the Adriatic Sea was investigated with special reference to the possible&lt;br&gt;source and mineralogical characteristics of transported dust from North Africa. The effect is&lt;br&gt;particularly examined in unique, isolated marine system, Rogoznica Lake (RL; 43&amp;#176; 32 &amp;#8217;N, 15&amp;#176; 58&amp;#8217;&lt;br&gt;E) through its biological response.&lt;br&gt;For that purpose, the MERRA-2 reanalysis data for dust deposition in the period 1989-&lt;br&gt;2019 were used. Annual dust deposition cycle in the Adriatic Sea has maximum in spring and fall&lt;br&gt;with stronger deposition in central and south. Wet deposition accounts for 63-92% of total&lt;br&gt;deposition and 75% of data contains less than 1.5% of the mass. Intensity classes are defined for&lt;br&gt;the remaining 25% and each refers to about 30% of the mass. On average, over 73 days per year&lt;br&gt;is of weak, 14.6 of moderate, and 3.65 of extreme intensity, which varies spatially. In order to&lt;br&gt;detect the specific synoptic patterns for the dust transport in relation to the dust sources activity&lt;br&gt;and deposition in the Adriatic Sea, the EOF analysis on 850 hPa was utilized. Positive or negative&lt;br&gt;mode phases correspond to deposition anomalies in the Adriatic Sea and can be related to particular&lt;br&gt;dust sources in North Africa.&lt;br&gt;Given the seasonal strong physicochemical stratification, relatively small volume, and only&lt;br&gt;source of freshwater and nutrients through precipitation during stratification, the Rogoznica Lake&lt;br&gt;proved ideal for monitoring desert dust deposition events, by monitoring nutrient concentration in&lt;br&gt;the surface layer (0&amp;#8211;2 m). For the 2000-2012 period no correlation with MERRA-2 deposition&lt;br&gt;time series were found, but biological activity as a direct consequence of nutrient increase was&lt;br&gt;observed during deposition events. Since the Adriatic Sea was proved to be phosphate (P) and iron&lt;br&gt;(Fe) limited, the mineralogical database was used to estimate the amount of deposited P and Fe&lt;br&gt;during intense deposition events.&lt;/p&gt;

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