The Mediterranean, populated by over 500 million people in about 30 countries facing the basin, is one of the main worldwide hotspot for climate change and air quality. The conditions that favor this situation are related with presence of anthropic (i.e. urban and marine) and natural (i.e. mineral dust and wildfires) pollutants. In the framework of the I-AMICA PON project (Infrastruttura di Alta tecnologia per il. Monitoraggio Integrato Climatico-Ambientale, http://www.i-amica.it/i-amica/?lang=en), in the Southern area of Italy, three Climatic Environmental Observatories have been activated at the end of 2014 at the sea coastal sites of: Lamezia Terme (Calabria Region, 38° 52' N 16° 13' E ), Lecce (Apulia, 40° 20' N 18° 7' E) and Capo Granitola (Sicily, 37°34' N 12° 39' E). Data are near real time transmitted to a common server, allowing to a fast common overview of the atmospheric composition over the Central Mediterranean Sea. To provide near-real-time (NRT) information on natural pollutantscontribution to the aerosol load, and in particular Saharan dust, three Climatic Environmental Observatories have been activated at the end of 2014 at the sea coastal sites of: Lamezia Terme (Calabria Region, 38° 52' N 16° 13' E), Lecce (Apulia, 40° 20' N 18° 7' E) and Capo Granitola (Sicily, 37°34' N 12° 39' E). In the framework of the I-AMICA PON project (Infrastruttura di Alta tecnologia per il. Monitoraggio Integrato Climatico-Ambientale, http://www.i-amica.it/i-amica/?lang=en), an algorithm able to capture in near real time the dust outbreak events over the sampling sites was developed. It is based on simultaneous real time analysis of optical aerosol properties, in particular, analysis ofthe scattering angstrom exponent (SAE) and single scattering albedo (SSA) while 3D air-mass back-trajectories (96 hour long) are used to corroborate the origin of air masses from North Africa. In this wayThis methodology allow to , a period of observation is flagged as "dust event" when a period of observation with a minimal duration for a fixed amount of time appropriately defined, when SSAE reports values less than 0.5 and SSAE is in the range 0.8-0.95 (Costabile at al., 2013), together with air-masses traced back to a defined northern Africa box. The simultaneity simultaneousof these occurrences of these aerosol properties at the three Observatories, flagged by the web-central-server, permits to identify and define the incidences of the transport in NRT on synoptic scale. All the Observatories are equipped with a TSI 3563 nephelometer (450, 550 and 700nm) and a MultiAngle Absorption Photometer, allowing to calculate SSA at 635 nm and SAE. These parameters are calculated on STD and truncation corrected measurements. By using measurement of absorption and scattering coefficients carried out by photometer and 3? nephelometer, the SSA and SAE characterization of the aerosol optical properties is carried out for all the sites. These parametersaerosol properties, togethercoupled with meteorological data and analysis of 3D air-mass back-trajectories, allow to identify the different classes of aerosol (Saharan dust, sea salt and anthropogenic pollution). In particular, SSA (an important parameter in climate forcing calculations) is an indicator of the relative absorbing nature of the aerosol while SAE provides information about the amount of coarse particle. The tool devised to detect the amount presence of mineral dust excludes the contribution of sea salt compound in the airborne particles that are usually present in significant concentration in coastal sites and capable of falsify the results.
Near real time detection of dust events over sSouth Italy: a new tool
M Busetto;P Cristofanelli;A Lupi;TC Landi;R Duchi;CR Calidonna;DContini;P Bonasoni
2015
Abstract
The Mediterranean, populated by over 500 million people in about 30 countries facing the basin, is one of the main worldwide hotspot for climate change and air quality. The conditions that favor this situation are related with presence of anthropic (i.e. urban and marine) and natural (i.e. mineral dust and wildfires) pollutants. In the framework of the I-AMICA PON project (Infrastruttura di Alta tecnologia per il. Monitoraggio Integrato Climatico-Ambientale, http://www.i-amica.it/i-amica/?lang=en), in the Southern area of Italy, three Climatic Environmental Observatories have been activated at the end of 2014 at the sea coastal sites of: Lamezia Terme (Calabria Region, 38° 52' N 16° 13' E ), Lecce (Apulia, 40° 20' N 18° 7' E) and Capo Granitola (Sicily, 37°34' N 12° 39' E). Data are near real time transmitted to a common server, allowing to a fast common overview of the atmospheric composition over the Central Mediterranean Sea. To provide near-real-time (NRT) information on natural pollutantscontribution to the aerosol load, and in particular Saharan dust, three Climatic Environmental Observatories have been activated at the end of 2014 at the sea coastal sites of: Lamezia Terme (Calabria Region, 38° 52' N 16° 13' E), Lecce (Apulia, 40° 20' N 18° 7' E) and Capo Granitola (Sicily, 37°34' N 12° 39' E). In the framework of the I-AMICA PON project (Infrastruttura di Alta tecnologia per il. Monitoraggio Integrato Climatico-Ambientale, http://www.i-amica.it/i-amica/?lang=en), an algorithm able to capture in near real time the dust outbreak events over the sampling sites was developed. It is based on simultaneous real time analysis of optical aerosol properties, in particular, analysis ofthe scattering angstrom exponent (SAE) and single scattering albedo (SSA) while 3D air-mass back-trajectories (96 hour long) are used to corroborate the origin of air masses from North Africa. In this wayThis methodology allow to , a period of observation is flagged as "dust event" when a period of observation with a minimal duration for a fixed amount of time appropriately defined, when SSAE reports values less than 0.5 and SSAE is in the range 0.8-0.95 (Costabile at al., 2013), together with air-masses traced back to a defined northern Africa box. The simultaneity simultaneousof these occurrences of these aerosol properties at the three Observatories, flagged by the web-central-server, permits to identify and define the incidences of the transport in NRT on synoptic scale. All the Observatories are equipped with a TSI 3563 nephelometer (450, 550 and 700nm) and a MultiAngle Absorption Photometer, allowing to calculate SSA at 635 nm and SAE. These parameters are calculated on STD and truncation corrected measurements. By using measurement of absorption and scattering coefficients carried out by photometer and 3? nephelometer, the SSA and SAE characterization of the aerosol optical properties is carried out for all the sites. These parametersaerosol properties, togethercoupled with meteorological data and analysis of 3D air-mass back-trajectories, allow to identify the different classes of aerosol (Saharan dust, sea salt and anthropogenic pollution). In particular, SSA (an important parameter in climate forcing calculations) is an indicator of the relative absorbing nature of the aerosol while SAE provides information about the amount of coarse particle. The tool devised to detect the amount presence of mineral dust excludes the contribution of sea salt compound in the airborne particles that are usually present in significant concentration in coastal sites and capable of falsify the results.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
