scholarly journals Simulation of fine organic aerosols in the western Mediterranean area during the ChArMEx 2013 summer campaign

2018 ◽  
Vol 18 (10) ◽  
pp. 7287-7312 ◽  
Author(s):  
Arineh Cholakian ◽  
Matthias Beekmann ◽  
Augustin Colette ◽  
Isabelle Coll ◽  
Guillaume Siour ◽  
...  
Keyword(s):  
Mediterranean Basin ◽  
Mass Concentration ◽  
Organic Aerosols ◽  
Western Mediterranean ◽  
Basis Set ◽  
Aerosol Formation ◽  
Standard Scheme ◽  
Western Mediterranean Basin ◽  
The Mediterranean ◽  
Fine Organic

Abstract. The simulation of fine organic aerosols with CTMs (chemistry–transport models) in the western Mediterranean basin has not been studied until recently. The ChArMEx (the Chemistry-Aerosol Mediterranean Experiment) SOP 1b (Special Observation Period 1b) intensive field campaign in summer of 2013 gathered a large and comprehensive data set of observations, allowing the study of different aspects of the Mediterranean atmosphere including the formation of organic aerosols (OAs) in 3-D models. In this study, we used the CHIMERE CTM to perform simulations for the duration of the SAFMED (Secondary Aerosol Formation in the MEDiterranean) period (July to August 2013) of this campaign. In particular, we evaluated four schemes for the simulation of OA, including the CHIMERE standard scheme, the VBS (volatility basis set) standard scheme with two parameterizations including aging of biogenic secondary OA, and a modified version of the VBS scheme which includes fragmentation and formation of nonvolatile OA. The results from these four schemes are compared to observations at two stations in the western Mediterranean basin, located on Ersa, Cap Corse (Corsica, France), and at Cap Es Pinar (Mallorca, Spain). These observations include OA mass concentration, PMF (positive matrix factorization) results of different OA fractions, and 14C observations showing the fossil or nonfossil origins of carbonaceous particles. Because of the complex orography of the Ersa site, an original method for calculating an orographic representativeness error (ORE) has been developed. It is concluded that the modified VBS scheme is close to observations in all three aspects mentioned above; the standard VBS scheme without BSOA (biogenic secondary organic aerosol) aging also has a satisfactory performance in simulating the mass concentration of OA, but not for the source origin analysis comparisons. In addition, the OA sources over the western Mediterranean basin are explored. OA shows a major biogenic origin, especially at several hundred meters height from the surface; however over the Gulf of Genoa near the surface, the anthropogenic origin is of similar importance. A general assessment of other species was performed to evaluate the robustness of the simulations for this particular domain before evaluating OA simulation schemes. It is also shown that the Cap Corse site presents important orographic complexity, which makes comparison between model simulations and observations difficult. A method was designed to estimate an orographic representativeness error for species measured at Ersa and yields an uncertainty of between 50 and 85 % for primary pollutants, and around 2–10 % for secondary species.

scholarly journals Simulation of fine organic aerosols in the western Mediterranean area during the ChArMEx 2013 summer campaign

2017 ◽  
Author(s):  
Arineh Cholakian ◽  
Matthias Beekmann ◽  
Augustin Colette ◽  
Isabelle Coll ◽  
Guillaume Siour ◽  
...  
Keyword(s):  
Mediterranean Basin ◽  
Mass Concentration ◽  
Organic Aerosols ◽  
Western Mediterranean ◽  
Basis Set ◽  
Aerosol Formation ◽  
Standard Scheme ◽  
Western Mediterranean Basin ◽  
The Mediterranean ◽  
Fine Organic

Abstract. The simulation of fine organic aerosols with CTMs (Chemistry Transport Models) in the western Mediterranean basin has not been studied until recently. The ChArMEx (the Chemistry-Aerosol Mediterranean Experiment) SOP 2 (Special Observation Period 2) intensive field campaign in summer of 2013 gathered a large and comprehensive dataset of observations allowing the study of different aspects of the Mediterranean atmosphere including the formation of organic aerosols (OA) in 3D models. In this study, we used the CHIMERE CTM to perform simulations for the duration of the SAFMED (Secondary Aerosol Formation in the MEDiterranean) period (July to August 2013) of this campaign. In particular, we evaluated four schemes for the simulation of OA, including the CHIMERE standard scheme, the VBS (Volatility Basis Set) standard scheme with two parameterizations including aging of biogenic secondary OA, and a modified version of the VBS scheme which includes fragmentation and formation of non-volatile OA. The results for these four schemes are compared to observations at two stations in the western Mediterranean basin, located in Cap Corse (Corsica) and Cap Es Pinar (Mallorca). These observations include OA mass concentration, PMF (positive matrix factorization) results of different OA fractions, and 14C observations showing the fossil or non-fossil origins of carbonaceous particles. It is concluded that the modified VBS scheme is close to observations in all three aspects mentioned above; the standard VBS scheme without BSOA (Biogenic Secondary Organic Aerosol) aging also has a satisfactory performance in simulating the mass concentration of OA, but not for the source origin analysis comparisons. In addition, the OA sources over the western Mediterranean basin are explored. OA shows a major biogenic origin, especially at several hundred meters height from the surface; however over the Gulf of Genoa near the surface, the anthropogenic origin is of similar importance. A general assessment of other species was performed to evaluate the robustness of the simulations for this particular domain before evaluating OA simulation schemes. It is also shown that the Cap Corse site presents important orographic complexity which makes comparison between model simulations and observations difficult. A method was designed to estimate an orographic representativeness error for a list of species and yields an uncertainty of between 50–85 % for primary pollutants, and around 2–10 % for secondary species, for these species model to observations comparisons are only little impacted by orography.

scholarly journals Size distribution and optical properties of mineral dust aerosols transported in the western Mediterranean

2015 ◽  
Vol 15 (15) ◽  
pp. 21607-21669 ◽  
Author(s):  
C. Denjean ◽  
F. Cassola ◽  
A. Mazzino ◽  
S. Triquet ◽  
S. Chevaillier ◽  
...  
Keyword(s):  
Optical Properties ◽  
Mediterranean Basin ◽  
Mineral Dust ◽  
Regional Climate ◽  
Source Region ◽  
Western Mediterranean ◽  
Source Regions ◽  
Western Mediterranean Basin ◽  
Large Particles ◽  
The Mediterranean

Abstract. This study presents in situ aircraft measurements of Saharan mineral dust transported over the western Mediterranean basin in June–July 2013 during the ChArMEx/ADRIMED (the Chemistry-Aerosol Mediterranean Experiment/Aerosol Direct Radiative Impact on the regional climate in the MEDiterranean region) airborne campaign. Dust events differing in terms of source region (Algeria, Tunisia and Morocco), time of tranport (1–5 days) and height of transport were sampled. Mineral dust were transported above the marine boundary layer, which conversely was dominated by pollution and marine aerosols. The dust vertical structure was extremely variable and characterized by either a single layer or a more complex and stratified structure with layers originating from different source regions. Mixing of mineral dust with pollution particles was observed depending on the height of transport of the dust layers. Dust layers carried higher concentration of pollution particles at intermediate altitude (1–3 km) than at elevated altitude (> 3 km), resulting in scattering Angstrom exponent up to 2.2 within the intermediate altitude. However, the optical properties of the dust plumes remained practically unchanged with respect to values previously measured over source regions, regardless of the altitude. Moderate light absorption of the dust plumes was observed with values of aerosol single scattering albedo at 530 nm ranging from 0.90 to 1.00 ± 0.04. Concurrent calculations from the aerosol chemical composition revealed a negligible contribution of pollution particles to the absorption properties of the dust plumes that was due to a low contribution of refractory black carbon in regards to the fraction of dust and sulfate particles. This suggests that, even in the presence of moderate pollution, likely a persistent feature in the Mediterranean, the optical properties of the dust plumes could be assimilated to those of native dust in radiative transfer simulations, modeling studies and satellite retrievals over the Mediterranean. Measurements also showed that the coarse mode of mineral dust was conserved even after 5 days of transport in the Mediterranean, which contrasts with the gravitational depletion of large particles observed during the transport of dust plumes over the Atlantic. Simulations with the WRF mesoscale meteorological model highlighted a strong vertical turbulence within the dust layers that could prevent deposition of large particles during their atmospheric transport. This has important implications for the dust radiative effects due to surface dimming, atmospheric heating and cloud formation. The results presented here add to the observational dataset necessary for evaluating the role of mineral dust on the regional climate and rainfall patterns in the western Mediterranean basin.

scholarly journals Evidence of a prolonged drought ca. 4200 yr BP correlated with prehistoric settlement abandonment from the Gueldaman GLD1 Cave, Northern Algeria

2016 ◽  
Vol 12 (1) ◽  
pp. 1-14 ◽  
Author(s):  
J. Ruan ◽  
F. Kherbouche ◽  
D. Genty ◽  
D. Blamart ◽  
H. Cheng ◽  
...  
Keyword(s):  
Mediterranean Basin ◽  
Eastern Mediterranean ◽  
Western Mediterranean ◽  
Faunal Remains ◽  
Carbon And Oxygen Isotopes ◽  
Northern Algeria ◽  
Western Mediterranean Basin ◽  
Prolonged Drought ◽  
Eastern Mediterranean Basin ◽  
The Mediterranean

Abstract. Middle Holocene cultures have been widely studied around the Eastern-Mediterranean basin in the last 30 years and past cultural activities have been commonly linked with regional climate changes. However, in many cases such linkage is equivocal, in part due to existing climatic evidence that has been derived from areas outside the distribution of ancient settlements, leading to uncertainty from complex spatial heterogeneity in both climate and demography. A few high-resolution well-dated paleoclimate records were recently established using speleothems in the Central and Eastern-Mediterranean basin, however, the scarcity of such records in the western part of the Mediterranean prevents us from correlating past climate evolutions across the basin and deciphering climate–culture relation at fine timescales. Here we report the first decadal-resolved Mid-Holocene climate proxy records from the Western-Mediterranean basin based on the stable carbon and oxygen isotopes analyses of two U/Th dated stalagmites from the Gueldaman GLD1 Cave in Northern Algeria. Comparison of our records with those from Italy and Israel reveals synchronous (multi) centennial dry phases centered at ca. 5600, ca. 5200 and ca. 4200 yr BP across the Mediterranean basin. New calibrated radiocarbon dating constrains reasonably well the age of rich anthropogenic deposits (e.g., faunal remains, pottery, charcoal) excavated inside the cave, which allows the comparison between in situ evidence of human occupation and of climate change. This approach shows that the timing of a prolonged drought at ca. 4400–3800 yr BP blankets the onset of cave abandonment shortly after ca. 4403 cal yr BP, supporting the hypothesis that a climate anomaly may have played a role in this cultural disruption.

scholarly journals Fuel loading and flammability in the Mediterranean Basin woody species with different post-fire regenerative strategies

2010 ◽  
Vol 19 (6) ◽  
pp. 783 ◽  
Author(s):  
S. Saura-Mas ◽  
S. Paula ◽  
J. G. Pausas ◽  
F. Lloret
Keyword(s):  
Mediterranean Basin ◽  
Fire Risk ◽  
Woody Species ◽  
Western Mediterranean ◽  
Fuel Load ◽  
Fuel Loading ◽  
Selective Pressures ◽  
Western Mediterranean Basin ◽  
The Mediterranean ◽  
The Mediterranean Basin

The flammability and combustibility of plant communities are determined by species features related to growth-form, structure and physiology. In some ecosystems, such as the Mediterranean ones, these characteristics may contribute to the existence of fire-prone species. We measured several parameters associated with the flammability and fuel loading of dominant woody species with different post-fire regenerative strategies (seeders and non-seeders) in shrublands in the western Mediterranean Basin. Overall, seeder species show lower fuel load but are more prone to burning owing to a higher dead-to-live fuel ratio, live fine-fuel proportion and dead fine-fuel proportion. Moreover, they burst into flame at lower temperatures than non-seeders. In the Mediterranean Basin, most seeder species emerged mainly during the Quaternary, under a highly fluctuating Mediterranean climate and during recurrent fires. We propose that properties related to the combustibility and flammability of seeders may be the result of selective pressures associated with both fire and climate. These results suggest that ecosystems dominated by seeder species are more susceptible to fire risk than those dominated by non-seeder species in the Mediterranean Basin. Therefore, the proportion of these types of species resulting from previous fire or management history is likely to determine the characteristics of future fire events.

scholarly journals New records of amphipod crustaceans along the Israeli Mediterranean coast, including a rare Mediterranean endemic species, Maera schieckei Karaman & Ruffo, 1971

2020 ◽  
Vol 8 ◽  
Author(s):  
Sabrina Lo Brutto ◽  
Davide Iaciofano
Keyword(s):  
Mediterranean Sea ◽  
Mediterranean Basin ◽  
Eastern Mediterranean ◽  
Aegean Sea ◽  
Western Mediterranean ◽  
Mediterranean Coast ◽  
Tyrrhenian Sea ◽  
Western Mediterranean Basin ◽  
The Mediterranean ◽  
Distribution And Ecology

A survey has been carried out at four Israeli rocky sites to evaluate the diversity of the amphipod fauna on various hard substrates, still scarcely monitored, as potential pabulum for amphipod crustacean species. A survey of shallow rocky reefs along the Mediterranean coast of Israel recovered 28 species and integrated the Amphipoda checklist for the country ofIsrael with 12 newly-recorded species. Such renewed national list includes Maera schieckei Karaman & Ruffo, 1971, a rare species endemic to the Mediterranean Sea, recorded here for the first time from the southern Levant Basin. The species, described from specimens collected in the Tyrrhenian Sea in 1970, has been only recorded eight times within the whole Mediterranean Sea. A revision of the bibliography on the distribution and ecology of M. schieckei showed that, although mentioned only for the western Mediterranean basin by some authors, it is listed in the checklist of amphipods of the Aegean Sea and neighbouring seas and has been found in the eastern Mediterranean basin since 1978. Maera schieckei was rarely found in the Mediterranean, one of the most studied marine biogeographic region as concerns the amphipod fauna; and the species seems to prefer bays or gulf areas. The role of updating and monitoring faunal composition should be re-evaluated.

scholarly journals Continental pollution in the Western Mediterranean Basin: vertical profiles of aerosol and trace gases measured over the sea during TRAQA 2012 and SAFMED 2013

2015 ◽  
Vol 15 (6) ◽  
pp. 8283-8328 ◽  
Author(s):  
C. Di Biagio ◽  
L. Doppler ◽  
C. Gaimoz ◽  
N. Grand ◽  
G. Ancellet ◽  
...  
Keyword(s):  
Urban Areas ◽  
Mediterranean Basin ◽  
Trace Gases ◽  
Western Mediterranean ◽  
Saharan Dust ◽  
Vertical Profiles ◽  
Free Troposphere ◽  
Aerosol Formation ◽  
Western Mediterranean Basin ◽  
Wide Range

Abstract. In this study we present airborne observations of aerosol and trace gases obtained over the sea in the Western Mediterranean Basin during the TRAQA (TRansport and Air QuAlity) and SAFMED (Secondary Aerosol Formation in the MEDiterranean) campaigns in summers 2012 and 2013. A total of 23 vertical profiles were measured up to 5000 m a.s.l. over an extended area (40–45° N latitude and 2° W–12° E longitude) including the Gulf of Genoa, Southern France, the Gulf of Lion, and the Spanish coast. TRAQA and SAFMED successfully measured a wide range of meteorological conditions which favoured the pollution export from different sources located around the basin. Also, several events of dust outflows were measured during the campaigns. Observations from the present study indicate that continental pollution largely affects the Western Mediterranean both close to coastal regions and in the open sea as far as ~250 km from the coastline. Aerosol layers not specifically linked with Saharan dust outflows are distributed ubiquitously which indicates quite elevated levels of background pollution throughout the Western Basin. The measured aerosol scattering coefficient varies between ~20 and 120 M m−1, while carbon monoxide (CO) and ozone (O3) mixing ratios are in the range of 60–170 and 30–85 ppbv, respectively. Pollution reaches 3000–4000 m in altitude and presents a very complex and highly stratified structure characterized by fresh and aged layers both in the boundary layer and in the free troposphere. Within pollution plumes the measured particle concentration in the Aitken (0.004–0.1 μm) and accumulation (0.1–1.0 μm) modes is between $\\sim 100$ and 5000–6000 s cm−3 (standard cm−3), which is comparable to the aerosol concentration measured in continental urban areas. Additionally, our measurements indicate the presence of highly concentrated Aitken layers (10 000–15 000 s cm−3) observed both close to the surface and in the free troposphere, possibly linked to the influence of new particle formation (NPF) episodes over the basin.

scholarly journals The Mediterranean is getting saltier

2014 ◽  
Vol 11 (1) ◽  
pp. 735-752 ◽  
Author(s):  
M. Borghini ◽  
H. Bryden ◽  
K. Schroeder ◽  
S. Sparnocchia ◽  
A. Vetrano
Keyword(s):  
Deep Water ◽  
Mediterranean Basin ◽  
Western Mediterranean ◽  
Intermediate Water ◽  
Deep Water Formation ◽  
The Past ◽  
Deep Waters ◽  
Western Mediterranean Basin ◽  
Water Formation ◽  
The Mediterranean

Abstract. The deep waters of the Mediterranean Sea have been getting saltier and warmer for at least the past 40 yr at rates of about 0.015 and 0.04 °C per decade. Here we show that two processes contribute to these increases in temperature and salinity. On interannual time scales, deep water formation events in severe winters transmit increasingly salty intermediate waters into the deep water. The second process is a steady downward flux of heat and salt through the halocline-thermocline that connects the Levantine Intermediate Water with the deep water. We illustrate these two processes with observations from repeat surveys of the western Mediterranean basin we have made over the past 10 yr.

scholarly journals Continental pollution in the western Mediterranean basin: vertical profiles of aerosol and trace gases measured over the sea during TRAQA 2012 and SAFMED 2013

2015 ◽  
Vol 15 (16) ◽  
pp. 9611-9630 ◽  
Author(s):  
C. Di Biagio ◽  
L. Doppler ◽  
C. Gaimoz ◽  
N. Grand ◽  
G. Ancellet ◽  
...  
Keyword(s):  
Mediterranean Basin ◽  
Trace Gases ◽  
Western Mediterranean ◽  
Vertical Profiles ◽  
Free Troposphere ◽  
Aerosol Formation ◽  
Mixing Ratios ◽  
Western Mediterranean Basin ◽  
Wide Range ◽  
Extended Area

Abstract. In this study we present airborne observations of aerosol and trace gases obtained over the sea in the western Mediterranean basin during the TRAQA (TRansport and Air QuAlity) and SAFMED (Secondary Aerosol Formation in the MEDiterranean) campaigns in summer 2012 and 2013. A total of 23 vertical profiles were measured up to 5000 m above sea level over an extended area (40–45° N and 2° W–12° E) including the Gulf of Genoa, southern France, the Gulf of Lion, and the Spanish coast. During TRAQA and SAFMED the study area experienced a wide range of meteorological conditions which favoured pollution export from different sources located around the basin. Also, several events of dust outflows were measured during the campaigns. Observations from the present study show that continental pollution largely affects the western Mediterranean both close to coastal regions and in the open sea as far as ~ 250 km from the coastline. The measured aerosol scattering coefficient varies between ~ 20 and 120 Mm−1, while carbon monoxide (CO) and ozone (O3) mixing ratios are in the range of 60–165 and 30–85 ppbv, respectively. Pollution reaches 3000–4000 m in altitude and presents a very complex and highly stratified structure characterized by fresh and aged layers both in the boundary layer and in the free troposphere. Within pollution plumes the measured particle concentration in the Aitken (0.004–0.1 μm) and accumulation (0.1–1.0 μm) modes is between ~ 30 and 5000–6000 scm−3 (standard cm−3), which is comparable to the aerosol concentration measured in continental areas under pollution conditions. Additionally, our measurements indicate the presence of highly concentrated Aitken layers (10 000–15 000 scm−3) observed both close to the surface and in the free troposphere, possibly linked to the influence of new particle formation (NPF) episodes over the basin.

Building with Water:

2019 ◽  
Vol 78 (2) ◽  
pp. 145-166
Author(s):  
Elizabeth Kassler-Taub
Keyword(s):  
Early Modern ◽  
Mediterranean Basin ◽  
Western Mediterranean ◽  
Alternative Path ◽  
Western Mediterranean Basin ◽  
New Strategy ◽  
The Mediterranean ◽  
The City

From the fifteenth through the seventeenth centuries, military engineers in the Mediterranean devised a new strategy for defending a city built on a peninsular site: a navigable canal was excavated through the neck of the landmass, severing the city from the coast and isolating it within the sea. In Building with Water: The Rise of the Island-City in the Early Modern Mediterranean, Elizabeth Kassler-Taub traces the development and dissemination of this overlooked urban type. She details how the “island-city” first emerged in the Adriatic and Ionian territories of the Venetian stato da mar and later swept across Spanish and Portuguese outposts in the western Mediterranean basin, where it was absorbed into a shared Iberian vernacular. By reconstructing the circulation of the island-city through this sprawling network of colonial frontiers, Kassler-Taub argues, we can chart an alternative path of architectural influence in the region, one that shifts our attention beyond the Italian and Spanish mainlands.

Molecular phylogenetic relationships among some stygobitic cirolanid species (Crustacea, Isopoda)

2010 ◽  
Vol 79 (2) ◽  
pp. 57-67 ◽  
Author(s):  
Mariella Baratti ◽  
Mariateresa Filippelli ◽  
Francesco Nardi ◽  
Giuseppe Messana
Keyword(s):  
Mediterranean Basin ◽  
Eastern Mediterranean ◽  
Mediterranean Area ◽  
Molecular Data ◽  
Western Mediterranean ◽  
Morphological Studies ◽  
Western Mediterranean Basin ◽  
Sister Clade ◽  
Molecular Phylogenetic ◽  
The Mediterranean

Within the Cirolanidae, a widespread family of marine isopods, about 23 genera are stygobitic and inhabit phreatic and anchialine ecosystems, with many endemic species. The Mediterranean area has a high biodiversity of subterranean cirolanids, which are considered thalassoid limnostygobionts. A molecular analysis was conducted using mtDNA genes to infer the phylogeny of species belonging to six of the seven stygobitic genera of Cirolanidae inhabiting the Mediterranean basin and to two American taxa: Faucheria faucheri, Marocolana delamarei, Saharolana seurati, Sphaeromides virei virei, Turcolana sp., 13 taxa of the genus Typhlocirolana and two American species, Antrolana lira and Speocirolana bolivari. The Typhlocirolana species are widespread in the western Mediterranean basin, with a concentration of taxa in the Maghreb region. Turcolana sp. is localised in the eastern Mediterranean, while F. faucheri and S. v. virei are north Mediterranean taxa. S. seurati, the taxon least morphologically adapted to subterranean life, belongs to a monospecific genus present in a Tunisian spring. The molecular phylogeny showed a high affinity among the American taxa and the Mediterranean Sphaeromides, clustering in the Sphaeromides group identified by previous morphological studies. Typhlocirolana species and M. delamarei constitute their sister clade within the Sphaeromides group. F. faucheri appears to be a sister clade of the Sphaeromides group. S. seurati, showing reduced troglobitic adaptations, assumes disparate and unsolved positions in the phylogenetic reconstructions. The molecular data suggest that a combination of vicariance and dispersal events, occurring from 180 to a few million years ago, combined to bring about the present distribution pattern of Mediterranean cirolanid isopods.

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