scholarly journals Primary aerosols and secondary inorganic aerosols budget over the Mediterranean basin during 2012 and 2013

2017 ◽  
Author(s):  
Jonathan Guth ◽  
Virginie Marécal ◽  
Béatrice Josse ◽  
Joaquim Arteta
Keyword(s):  
Mediterranean Basin ◽  
Transport Model ◽  
Wide Band ◽  
Sea Salts ◽  
Monthly Basis ◽  
Desert Dust ◽  
Inorganic Aerosols ◽  
Sulphate Aerosols ◽  
The Mediterranean ◽  
The Mediterranean Basin

Abstract. In the frame of the Chemistry-Aerosol Mediterranean Experiment (ChArMEx), we analyse the budget of primary aerosols and secondary inorganic aerosols over the Mediterranean basin during the years 2012 and 2013. To do this, we use a two-years long numerical simulation with the Chemistry-Transport Model MOCAGE validated against satellite and ground based measurements. The budget is presented on an annual and a monthly basis on a domain covering 29° North to 47° North latitude and 10° West to 38° East longitude. The years 2012 and 2013 show similar seasonal variations. The desert dust is the main contributor to the annual burden in the Mediterranean region with a peak in spring. The secondary inorganic aerosols, taken as a whole, also contribute significantly as well as sea salts. Sulphate aerosols have a maximum in summer and sea salts in winter, while nitrate and ammonium aerosols do not exhibit large seasonal changes. The results show that all the considered types of aerosols, except for sea salt aerosols, have a net import/export term that is negative, meaning that aerosols emitted and chemically produced within the domain are transported out, with high values for some of them. For example, around 40 % of the emitted black carbon are exported. The main sources of changes between 2012 and 2013 are wind variations acting on the desert dust emissions and the import of aerosols from North American fires. In order to assess the importance of the emissions of the marine and the coastal areas, we made a sensitivity test simulation. This simulation is similar to the first one but with the removal of the anthropogenic emissions over the sea and over a 50 km wide band inland along the coast. It shows that about a third of the aerosols emitted and chemically produced and about a half of the exported part in the Mediterranean basin originate from the marine and coastal area, meaning that anthropogenic air pollution from primary aerosols and secondary inorganic aerosols in this region mainly comes from local emissions.

scholarly journals Primary aerosol and secondary inorganic aerosol budget over the Mediterranean Basin during 2012 and 2013

2018 ◽  
Vol 18 (7) ◽  
pp. 4911-4934 ◽  
Author(s):  
Jonathan Guth ◽  
Virginie Marécal ◽  
Béatrice Josse ◽  
Joaquim Arteta ◽  
Paul Hamer
Keyword(s):  
Mediterranean Basin ◽  
Transport Model ◽  
Coastal Areas ◽  
Sea Salt ◽  
Anthropogenic Emissions ◽  
Carbonaceous Aerosols ◽  
Desert Dust ◽  
Inorganic Aerosols ◽  
The Mediterranean ◽  
The Mediterranean Basin

Abstract. In the frame of the Chemistry-Aerosol Mediterranean Experiment (ChArMEx), we analyse the budget of primary aerosols and secondary inorganic aerosols over the Mediterranean Basin during the years 2012 and 2013. To do this, we use two year-long numerical simulations with the chemistry-transport model MOCAGE validated against satellite- and ground-based measurements. The budget is presented on an annual and a monthly basis on a domain covering 29 to 47° N latitude and 10° W to 38° E longitude. The years 2012 and 2013 show similar seasonal variations. The desert dust is the main contributor to the annual aerosol burden in the Mediterranean region with a peak in spring, and sea salt being the second most important contributor. The secondary inorganic aerosols, taken as a whole, contribute a similar level to sea salt. The results show that all of the considered aerosol types, except for sea salt aerosols, experience net export out of our Mediterranean Basin model domain, and thus this area should be considered as a source region for aerosols globally. Our study showed that 11 % of the desert dust, 22.8 to 39.5 % of the carbonaceous aerosols, 35 % of the sulfate and 9 % of the ammonium emitted or produced into the study domain are exported. The main sources of variability for aerosols between 2012 and 2013 are weather-related variations, acting on emissions processes, and the episodic import of aerosols from North American fires. In order to assess the importance of the anthropogenic emissions of the marine and the coastal areas which are central for the economy of the Mediterranean Basin, we made a sensitivity test simulation. This simulation is similar to the reference simulation but with the removal of the international shipping emissions and the anthropogenic emissions over a 50 km wide band inland along the coast. We showed that around 30 % of the emissions of carbonaceous aerosols and 35 to 60 % of the exported carbonaceous aerosols originates from the marine and coastal areas. The formation of 23, 27 and 27 %, respectively of, ammonium, nitrate and sulfate aerosols is due to the emissions within the marine and coastal area.

scholarly journals Impact of the Asian monsoon anticyclone on the variability of mid-to-upper tropospheric methane above the Mediterranean Basin

2014 ◽  
Vol 14 (20) ◽  
pp. 11427-11446 ◽  
Author(s):  
P. Ricaud ◽  
B. Sič ◽  
L. El Amraoui ◽  
J.-L. Attié ◽  
R. Zbinden ◽  
...  
Keyword(s):  
Mediterranean Basin ◽  
Near Infrared ◽  
Asian Monsoon ◽  
Climate Models ◽  
Transport Model ◽  
Lower Troposphere ◽  
Upper Troposphere ◽  
The Mediterranean ◽  
East West ◽  
The Mediterranean Basin

Abstract. The space and time variabilities of methane (CH4) total column and upper tropospheric mixing ratios are analysed above the Mediterranean Basin (MB) as part of the Chemical and Aerosol Mediterranean Experiment (ChArMEx) programme. Since the analysis of the mid-to-upper tropospheric CH4 distribution from spaceborne sensors and model outputs is challenging, we have adopted a climatological approach and have used a wide variety of data sets. We have combined spaceborne measurements from the Thermal And Near infrared Sensor for carbon Observations – Fourier Transform Spectrometer (TANSO-FTS) instrument on the Greenhouse gases Observing SATellite (GOSAT) satellite, the Atmospheric InfraRed Spectrometer (AIRS) on the AURA platform and the Infrared Atmospheric Sounder Interferometer (IASI) instrument aboard the MetOp-A platform with model results from the Chemical Transport Model (CTM) MOCAGE, and the Chemical Climate Models (CCMs) CNRM-AOCCM and LMDz-OR-INCA (according to different emission scenarios). In order to minimize systematic errors in the spaceborne measurements, we have only considered maritime pixels over the MB. The period of interest spans from 2008 to 2011 considering satellite and MOCAGE data and, regarding the CCMs, from 2001 to 2010. Although CH4 is a long-lived tracer with lifetime of ~12 years and is supposed to be well mixed in the troposphere, an east–west gradient in CH4 is observed and modelled in the mid-to-upper troposphere with a maximum in the Western MB in all seasons except in summer when CH4 accumulates above the Eastern MB. The peak-to-peak amplitude of the east–west seasonal variation in CH4 above the MB in the upper troposphere (300 hPa) is weak but almost twice as great in the satellite measurements (~25 ppbv) as in the model data (~15 ppbv). The maximum of CH4 in summer above the eastern MB can be explained by a series of dynamical processes only occurring in summer. The Asian monsoon traps and uplifts high amounts of CH4 to the upper troposphere where they build up. The Asian Monsoon Anticyclone redistributes these elevated CH4 amounts towards North Africa and the Middle East to finally reach and descend in the eastern MB. In the lower troposphere, the CH4 variability is mainly driven by the local sources of emission in the vicinity of the MB.

scholarly journals Variability of tropospheric methane above the Mediterranean Basin inferred from satellite and model data

2014 ◽  
Vol 14 (7) ◽  
pp. 9975-10024
Author(s):  
P. Ricaud ◽  
B. Sič ◽  
L. El Amraoui ◽  
J.-L. Attié ◽  
P. Huszar ◽  
...  
Keyword(s):  
Middle East ◽  
Atlantic Ocean ◽  
Mediterranean Basin ◽  
Near Infrared ◽  
Asian Monsoon ◽  
Transport Model ◽  
Emission Scenarios ◽  
The West ◽  
The Mediterranean ◽  
The Mediterranean Basin

Abstract. The space and time variabilities of methane (CH4) total column and upper tropospheric mixing ratios are analyzed above the Mediterranean Basin (MB) as part of the Chemical and Aerosol Mediterranean Experiment (ChArMEx) programme. Spaceborne measurements from the Thermal And Near infrared Sensor for carbon Observations-Fourier Transform Spectrometer (TANSO-FTS) instrument on the Greenhouse gases Observing SATellite (GOSAT) satellite, the Atmospheric InfraRed Spectrometer (AIRS) on the AURA platform and the Infrared Atmospheric Sounder Interferometer (IASI) instrument aboard the MetOp-A platform are used in conjunction with model results from the Chemical Transport Model (CTM) MOCAGE, and the Chemical Climate Models (CCMs) CNRM-AOCCM and LMDz-OR-INCA (according to different emission scenarios). In order to minimize systematic errors in the spaceborne measurements, we have only considered maritime pixels over the MB. The period under interest spans from 2008 to 2011 considering satellite and MOCAGE data and, regarding the CCMs, from 2001 to 2010. An East-West gradient in CH4 is observed and modelled whatever the season considered. In winter, air masses mainly originating from Atlantic Ocean and Europe tend to favour an elevated amount of mid-to-upper tropospheric CH4 in the West vs. the East of the MB, with a general upward transport above the MB. In summer, the meteorological state of the MB is changed, favouring air from Northern Africa and Middle East together with Atlantic Ocean and Europe, with a general downward motion above the MB. The Asian Monsoon traps and uplifts high amounts of CH4 that are transported towards North Africa and Middle East by the Asian Monsoon Anticyclone to finally reach and descent in the East of the MB. Consequently, the mid-to-upper tropospheric CH4 is much greater in the East than in the West of the MB. The seasonal variation of the difference in CH4 between the East and the West MB does show a maximum in summer for pressures from 500 to 100 hPa considering both spaceborne measurements and model results whatever the emission scenarios used. From this study, we can conclude that CH4 in the mid-to-upper troposphere over the MB is mainly affected by long-range transport, particularly intense in summer from Asia. In the low-to-mid troposphere, the local sources of emission in the vicinity of the MB mainly affect the CH4 variability.

scholarly journals Intercontinental transport of biomass burning pollutants over the Mediterranean Basin during the summer 2014 ChArMEx-GLAM airborne campaign

2018 ◽  
Vol 18 (9) ◽  
pp. 6887-6906 ◽  
Author(s):  
Vanessa Brocchi ◽  
Gisèle Krysztofiak ◽  
Valéry Catoire ◽  
Jonathan Guth ◽  
Virginie Marécal ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Mediterranean Basin ◽  
Transport Model ◽  
Particle Dispersion ◽  
Transport Processes ◽  
Atmospheric Composition ◽  
Air Mass ◽  
Air Masses ◽  
The Mediterranean ◽  
The Mediterranean Basin

Abstract. The Gradient in Longitude of Atmospheric constituents above the Mediterranean basin (GLAM) campaign was set up in August 2014, as part of the Chemistry and Aerosol Mediterranean Experiment (ChArMEx) project. This campaign aimed to study the chemical variability of gaseous pollutants and aerosols in the troposphere along a west–east transect above the Mediterranean Basin (MB). In the present work, we focus on two biomass burning events detected at 5.4 and 9.7 km altitude above sea level (a.s.l.) over Sardinia (from 39∘12′ N–9∘15′ E to 35∘35′ N–12∘35′ E and at 39∘30′ N–8∘25′ E, respectively). Concentration variations in trace gas carbon monoxide (CO), ozone (O3) and aerosols were measured thanks to the standard instruments on board the Falcon 20 aircraft operated by the Service des Avions Français Instrumentés pour la Recherche en Environnement (SAFIRE) and the Spectromètre InfraRouge In situ Toute Altitude (SPIRIT) developed by LPC2E. Twenty-day backward trajectories with Lagrangian particle dispersion model FLEXPART (FLEXible PARTicle) help to understand the transport processes and the origin of the emissions that contributed to this pollution detected above Sardinia. Biomass burning emissions came (i) on 10 August from the North American continent with air masses transported during 5 days before arriving over the MB, and (ii) on 6 August from Siberia, with air masses travelling during 12 days and enriched in fire emission products above Canada 5 days before arriving over the MB. In combination with the Global Fire Assimilation System (GFAS) inventory and the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite fire locations, FLEXPART reproduces well the contribution of those fires to CO and aerosols enhancements under adjustments of the injection height to 10 km in both cases and application of an amplification factor of 2 on CO GFAS emissions for the 10 August event. The chemistry transport model (CTM) MOCAGE is used as a complementary tool for the case of 6 August to confirm the origin of the emissions by tracing the CO global atmospheric composition reaching the MB. For this event, both models agree on the origin of air masses with CO concentrations simulated with MOCAGE lower than the observed ones, likely caused by the coarse model horizontal resolution that yields the dilution of the emissions and diffusion during transport. In combination with wind fields, the analysis of the transport of the air mass documented on 6 August suggests the subsidence of CO pollution from Siberia towards North America and then a transport to the MB via fast jet winds located at around 5.5 km in altitude. Finally, using the ratio ΔO3 ∕ ΔCO, the plume age can be estimated and the production of O3 during the transport of the air mass is studied using the MOCAGE model.

scholarly journals Intercontinental transport of biomass burning pollutants over the Mediterranean Basin during the summer 2014 ChArMEx-GLAM airborne campaign

2017 ◽  
Author(s):  
Vanessa Brocchi ◽  
Gisèle Krysztofiak ◽  
Valéry Catoire ◽  
Jonathan Guth ◽  
Virginie Marécal ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Mediterranean Basin ◽  
Transport Model ◽  
Dispersion Model ◽  
Particle Dispersion ◽  
Transport Processes ◽  
Atmospheric Composition ◽  
Air Masses ◽  
The Mediterranean ◽  
The Mediterranean Basin

Abstract. The Gradient in Longitude of Atmospheric constituents above the Mediterranean basin (GLAM) campaign was set up in August 2014, as part of the Chemistry-Aerosol Mediterranean Experiment (ChArMEx) project. This campaign aimed at studying the chemical variability of gaseous pollutants and aerosols in the troposphere along a West-East transect above the Mediterranean Basin (MB). In the present work, we focus on two biomass burning events detected at 5.4 and 9.7 km altitude above sea level (asl) above Sardinia (from 39°12 N–9°15 E to 35°35 N–12°35 E and at 39°30 N–8°25 E, respectively). Concentration variations in trace gas carbon monoxide (CO) and aerosols were measured thanks to the standard instruments on-board the Falcon-20 aircraft operated by the Service des Avions Français Instrumentés pour la Recherche en Environnement (SAFIRE) and the Spectromètre InfraRouge In situ Toute Altitude (SPIRIT) developed by LPC2E. 20-day backward trajectories with Lagrangian particle dispersion model FLEXPART (FLEXible PARTicle) help understanding the transport processes and the origin of the emissions that contributed to these pollutions detected above Sardinia. Biomass burning emissions came (i) on 10 August from the Northern American continent with air masses transported during 5 days before arriving over the MB, and (ii) on 6 August from Siberia with air masses travelling during 12 days and enriched in fire emission products above Canada 5 days before arriving over the MB. In combination with the Global Fire Assimilation System (GFAS) inventory and the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite fire locations, FLEXPART reproduces well the contribution of those fires to CO and aerosols enhancements under adjustments of the injection height to 10 km in both cases, and application of an amplification factor of 2.5 on CO GFAS emissions for the 10 August event. The chemistry transport model (CTM) MOCAGE is used as a complementary tool for the case of 6 August to confirm the origin of the emissions by tracing the CO global atmospheric composition reaching the MB. For this event, both models agree on the origin of air masses with CO concentrations simulated with MOCAGE lower than the observed ones, likely caused by the coarse model horizontal resolution that yields the dilution of the emissions and diffusion during transport. In combination with wind fields, the analysis of the transport of the air mass documented on 6 August suggests the subsidence of CO pollution from Siberia towards North America and then a transport to the MB via fast jet winds located at around 5.5 km in altitude.

scholarly journals The regime of desert dust episodes in the Mediterranean based on contemporary satellite observations and ground measurements

2013 ◽  
Vol 13 (6) ◽  
pp. 16247-16299 ◽  
Author(s):  
A. Gkikas ◽  
N. Hatzianastassiou ◽  
N. Mihalopoulos ◽  
V. Katsoulis ◽  
S. Kazadzis ◽  
...  
Keyword(s):  
Mediterranean Basin ◽  
Western Mediterranean ◽  
Spatial And Temporal Variability ◽  
Central Mediterranean ◽  
Study Region ◽  
Desert Dust ◽  
Western Mediterranean Basin ◽  
Spatial Coverage ◽  
The Mediterranean ◽  
The Mediterranean Basin

Abstract. The regime of desert dust (DD) episodes over the broader Mediterranean basin is studied for the period 2000–2007. The novelty of this work lies in its complete spatial coverage of the region. An objective and dynamic algorithm has been set up, which uses daily measurements of various aerosol optical properties taken by different satellite databases, enabling the identification of DD episodes and their classification into strong and extreme ones. The algorithm's performance was tested against surface based (in situ) Particulate Matter (PM) and (columnar) sun-photometric AERONET measurements from stations distributed across the Mediterranean. The comparisons have shown the reasonable ability of the algorithm to detect the DD episodes taking place within the study region. The largest disagreements with PM data were found in summer and western Mediterranean, when African dust transport has a great vertical extent that cannot be satisfactorily captured by surface measurements. According to our results, DD episodes in the Mediterranean basin are quite frequent (up to 11.4 episodes/year) while there is a significant spatial and temporal variability in their frequency of occurrence and their intensity. Strong episodes occur more frequently in the western Mediterranean basin whilst extreme ones appear more frequently over central Mediterranean Sea areas. Apart from this longitudinal variation, there is a predominant latitudinal variability in both frequency and intensity, with decreasing values from south to north. A significant seasonal variation was also found for the frequency of DD episodes, with both strong and extreme episodes being more frequent during summer in the western Mediterranean basin, but during spring in its central and eastern parts. In most cases (>85%) the Mediterranean dust episodes last a bit longer than a day, although their duration can reach 6 days for strong episodes and 4 days for extreme episodes. A noticeable year by year variability was also found, especially for the frequency of the episodes. The spatial and temporal patterns of Mediterranean DD episodes can be explained based on surface pressure and precipitation spatio-temporal distribution patterns over the study region, as well as by the year by year variability of North Atlantic Oscillation (NAO). In this context, a decreasing frequency of appearance of DD episodes over the Mediterranean basin has been revealed over the period 2000–2007, especially over land surfaces, in line with decreasing NAO Index over the same period. Our findings demonstrate the reasonable ability to detect desert dust outbreaks in the Mediterranean basin from satellites.

Piracy and Law in the Ottoman Mediterranean

2017 ◽  
Author(s):  
Joshua M. White
Keyword(s):  
International Law ◽  
Mediterranean Basin ◽  
Islamic Law ◽  
Comprehensive Examination ◽  
Legal Space ◽  
The Mediterranean ◽  
First Time ◽  
Eastern Half ◽  
The Mediterranean Basin

This book offers a comprehensive examination of the shape and impact of piracy in the eastern half of the Mediterranean and the Ottoman Empire’s administrative, legal, and diplomatic response. In the late sixteenth and seventeenth centuries, piracy had a tremendous effect on the formation of international law, the conduct of diplomacy, the articulation of Ottoman imperial and Islamic law, and their application in Ottoman courts. Piracy and Law draws on research in archives and libraries in Istanbul, Venice, Crete, London, and Paris to bring the Ottoman state and Ottoman victims into the story for the first time. It explains why piracy exploded after the 1570s and why the Ottoman state was largely unable to marshal an effective military solution even as it responded dynamically in the spheres of law and diplomacy. By focusing on the Ottoman victims, jurists, and officials who had to contend most with the consequences of piracy, Piracy and Law reveals a broader range of piratical practitioners than the Muslim and Catholic corsairs who have typically been the focus of study and considers their consequences for the Ottoman state and those who traveled through Ottoman waters. This book argues that what made the eastern half of the Mediterranean basin the Ottoman Mediterranean, more than sovereignty or naval supremacy—which was ephemeral—was that it was a legal space. The challenge of piracy helped to define its contours.

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