http://hdl.handle.net/2122/88 Search the Channel search http://www.earth-prints.org/simple-search http://hdl.handle.net/2122/3993 Title: Biomonitoring of traffic air pollution in Rome using magnetic properties of tree leaves <br/> <br/>Authors: Moreno, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Sagnotti, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Dinarès-Turell, J.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Winkler, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Cascella, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia <br/> <br/>Abstract: We report a biomonitoring study of air pollution in Rome based on the magnetic properties of tree leaves. In a first step, magnetic properties of leaves from different tree species from the same location were compared. It was observed that leaves of evergreen species, like Quercus ilex, present much higher magnetic intensities than those of deciduous species, like Platanus sp., suggesting that leaves accumulate magnetic pollutants during their whole lifespan. In a second step, leaves from Q. ilex and Platanus sp. trees, both very common in Rome, have been used to monitor traffic emission pollution in two different periods. A Platanus sp. sampling campaign was undertaken in October 2001, at the end of the seasonal vegetational cycle, and 5 Q. ilex monthly sampling campaigns from April to August 2002. The strong difference observed in the magnetic susceptibility from leaves collected in green areas and roads allowed the realization of detailed pollution distribution maps from the south of Rome. Magnetic properties indicate that high concentrations and relatively larger grain-sizes of magnetic particles are observed in trees located along roads with high vehicle traffic and in the vicinity of railways. The decrease in concentration and grain size of magnetic particles with distance from the roadside confirms that magnetic properties of leaves are related to air pollution from vehicle emissions. The results indicate that a magnetic survey of tree leaves, which is relatively rapid and inexpensive, may be used in addition to the classical air quality monitoring systems to identify and delineate high-polluted areas in urban environments. http://hdl.handle.net/2122/3848 Title: History of glacial terminations from the Tiber River, Rome: Insights into glacial forcing mechanisms <br/> <br/>Authors: Marra, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Boschi, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione AC, Roma, Italia <br/> <br/>Abstract: We document the aggradational history of the Tiber River delta through the last 17,000 years by means of 17 new 14C ages from peat or wood collected from the delta sediment. An abrupt change in sediment clast size, grading from gravel to clay, occurred between 13.63 (±0.20) and 12.80 (±0.15) ka, indicating that it was synchronous with the last glacial termination, with no appreciable phase lag. Knowing this phase relationship enables us to reduce the magnitudes of age uncertainties for aggradational sections corresponding to glacial terminations IX through III, which we had dated previously by 40Ar/39Ar methods. Glacial terminations VIII, VI, and IV precede beyond 95% confidence the ages predicted by Northern Hemisphere summer insolation maxima. Additionally, we find that each of these seven glacial terminations follows particularly mild insolation minima, which we suggest may be regarded as the preconditioning factor to trigger a glacial termination. http://hdl.handle.net/2122/2216 Title: Propagation of dikes at Vesuvio (Italy) and the effect of Mt. Somma <br/> <br/>Authors: Acocella, V.; Dipartimento di Scienze Geologiche, Universita` Roma Tre, Rome; Porreca, M.; Dipartimento di Scienze Geologiche, Universita` Roma Tre, Rome; Neri, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Massimi, E.; Dipartimento di Scienze Geologiche, Universita` Roma Tre, Rome; Mattei, M.; Dipartimento di Scienze Geologiche, Universita` Roma Tre, Rome <br/> <br/>Abstract: Dikes provide crucial information on how magma propagates within volcanoes. Somma-Vesuvio (Italy) consists of the active Vesuvio cone, partly bordered by the older Mt. Somma edifice. Historical chronicles on the fissure eruptions in 1694–1944 are matched with an analytical solution to define the propagation path of the related dikes and to study any control of the Mt. Somma relief. The fissures always consisted of the downslope migration of vents from an open summit conduit, indicating lateral propagation as the predominant mechanism for shallow dike emplacement. No fissure emplaced beyond Mt. Somma, suggesting that its buttressing hinders the propagation of the radial dikes. An analytical solution is defined to describe the mechanism of formation of the laterally propagating dikes and to evaluate the effect of topography. The application to Somma-Vesuvio suggests that, under ordinary excess magmatic pressures, the dikes should not propagate laterally at depths >240–480 m below the surface, as the increased lithostatic pressure requires magmatic pressures higher than average. This implies that, when the conduit is open, the lateral emplacement of dikes is expectable on the S, Wand E slopes. The lack of fissures N of Mt. Somma is explained by its buttressing, which hinders dike propagation. Citation: Acocella, V., M. Porreca, M. Neri, E. Massimi, and M. Mattei (2006), Propagation of dikes at Vesuvio (Italy) and the effect of Mt. Somma, Geophys. Res. Lett., 33, L08301, doi:10.1029/2005GL025590. http://hdl.handle.net/2122/1970 Title: Perspectives of 2D and 3D mapping of atmospheric pollutants over urban areas by means of airborne DOAS spectrometers <br/> <br/>Authors: Giovanelli, G.; Istituto di Scienze dell’Atmosfera e del Clima (ISAC), CNR, Bologna, Italy; Palazzi, E.; Istituto di Scienze dell’Atmosfera e del Clima (ISAC), CNR, Bologna, Italy; Petritoli, A.; Istituto di Scienze dell’Atmosfera e del Clima (ISAC), CNR, Bologna, Italy; Bortoli, D.; Geophysics Centre of Évora - University of Évora (CGE-UE), Évora, Portugal; Kostadinov, I.; Solar-Terrestrial Influences Laboratory (STIL), Bulgarian Academy of Science, Stara Zagora, Bulgaria; Margelli, F.; Istituto di Scienze dell’Atmosfera e del Clima (ISAC), CNR, Bologna, Italy; Pagnutti, S.; Istituto di Scienze dell’Atmosfera e del Clima (ISAC), CNR, Bologna, Italy; Premuda, M.; ENEA, Divisione Fisica Applicata, Centro Ricerche Bologna, Italy; Ravegnani, F.; Istituto di Scienze dell’Atmosfera e del Clima (ISAC), CNR, Bologna, Italy; Trivellone, G.; Istituto di Scienze dell’Atmosfera e del Clima (ISAC), CNR, Bologna, Italy <br/> <br/>Abstract: tants, offering numerous advantages over conventional networks of in situ analysers. We propose some innovative solutions in the field of DOAS (Differential Optical Absorption Spectroscopy) remote systems, utilizing diffuse solar light as the radiation source. We examine the numerous potentialities of minor gas slant column calculations, applying the «off-axis» methodology for collecting the diffuse solar radiation. One of these particular approaches, using measurements along horizontal paths, has already been tested with the spectrometer installed on board the Geophysica aircraft during stratospheric flights up to altitudes of 20 km. The theoretical basis of these new measurement techniques using DOAS remote sensing systems are delineated to assess whether low altitude flights can provide 2D and 3D pollution tomography over metropolitan areas. The 2D or 3D trace gas total column mapping could be used to investigate: i) transport and dispersion phenomena of air pollution, ii) photochemical process rates, iii) gas plume tomography, iv) minor gas vertical profiles into the Planetary Boundary Layer and v) minor gas flux divergence over a large area.