(DONAIRE Project). NAIR O E D T
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Preliminary magnetic evaluation of air quality monitoring in north-east Spain (DONAIRE Project). NAIR O E D T. Mochales1 , J.C. Larrasoaña 1 , J. Pey 1 , N. Pérez 2, J.C. Cerro 3 , M. Tobar 3, I. de la Parra 4 , J. Reyes 1 , P. Mata 1 [email protected] 1 IGME, 2 IDAEA-CSIC, 3 UIB, 4 UNIZAR DONAIRE operate in the NE Spain: Navarra, Aragon, Cataluña, Baleares Islands Locations respond to scientific criteria: What happens in remote areas? How much our cities contribute to atmospheric transfers? Type of movements in industrial zones We want to know what is transferred from the atmosphere to the Earth's surface in different microenvironments 20 20 Saharan Zaragoza Chiprana Pamplona Orgi 15 dust 15 10 10 5 5 Fig. 1. Location of collection sites in NE Spain and panorama of 0 0 agricultural terrains if Monegros desert (Huesca, Spain). Period 4 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10 AIM: We investigate magnetic properties of -5 -5 atmospheric deposition, from pristine to indus- trial environements (Fig. 2). Desposited dust was collected every 15 days and measuren intro -10 -10 ten periods. In order to characterize atmosphe- Saharan ric deposition we measured magnetic suscepti- 50*10-6 S.I. dust bility and intend to measure other magnetic properties in future (ARM, IRM; etc.) 20 20 Barcelona Palma de Mallorca Montseny Hospital Joan March RESULTS: Magnetic susceptibility values were measured in urban 15 15 areas (FIg. 3, red bars) and compared with the nearest natural mag- netic backgrounds (Fig 3, green bars). Anlysis revals high vales (10- 20*10-6 S.I.) in sites where anthropogenic activity is important 10 10 (Zaragoza, Pamplona, Barcelona y Palma de Mallorca), whereas low values (from -5 to 5*10-6 S.I.) are detected their clear analogues 5 5 (Chiprana, Orgi, Montseny, Hospital Joan March). Concentrations of magnetic minerals appear to be linked to prevalent component of 0 0 Saharan dust, as can be seen in period 4 in Ebro Valley areas 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10 Period 9-10 (Zaragoza, Chiprana, Almudévar, Ejea de los Caballeros) and in period 9 in Mediterranean area (Barcelona,Montseny, Palma de -5 -5 Mallorca, Hospital Joan March), in both anthropic and pristine sites. -10 -10 Variable contents in magnetic minerals are linked to industrial actu- Fig. 3. Comparison of magnetic susceptibility (*10-6 S.I.) in clean natural environments (green) vity (Monzón and Almudévar sites). On the other hand, agricultural and the nearest cities (red) during 10 sampling periods. Saharan dust concentration correspon- ding to periods 4 and 9 (http://www.bsc.es/projects/earthscience/visor/dust/). site (Ejea de los Caballeros) is directly related to amount of mass (g) and precipitantions peaks (Fig 4). Industrial or pristine areas show in variable contents Fe particles (SEM images, Fig. 5) 20 20 20 20 Ejea de los Monzón Almudévar Ordesa Caballeros 15 15 15 15 10 10 10 10 5 5 5 5 0 0 0 0 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10 -5 -5 -5 -5 -10 -10 -10 -10 Fig. 4. Magnetic susceptibility (*10-6 S.I.) in idustrial environments (blue), agricultural exploitation (brown) and National Park (green) Fig. 2. Detail of filters collected in the DONAIRE project. Remote Fig. 5. SEM images, showing Fe particles in Monzón, period 10 and Ordesa, period 8. sites show clearer filters whereas darker correspond to cities. Red shades are linked to episodes of Saharan dust. CONCLUSIONS: Magnetic susceptibility can help to discriminate anthropogenic and Saharan episodes by Acknowledgments: DONAIRE Project (CGL2015-68993-R) characterizing atmospheric deposition in cities and their near natural environments. References: Larrasoaña J.C., Roberts A.P., et al. (2003). Three million years of monsoon variability over the northern Sahara. Climate Dynamics 21, 689–698. Industrial areas show medium susceptibility values while pristine areas present systematically low values. Sagnotti L., Macrì P., et al. (2006). Magnetic properties of atmospheric particulate matter from automatic air sampler stations in Latium (Italy): toward a definition of magnetic fingerprints for natural and anthropogenic PM10 sources. Journal of Geophysical Research-Solid Earth 111, B12S22..