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LORENZO GUERRIERI

DIPENDENTE ALTRO ENTE DI RICERCA presso: Dipartimento di Ingegneria "Enzo Ferrari"


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Pubblicazioni

2014 - Sea Ice Area Investigation over the East Greenland Sea during 2003-13 [Abstract in Atti di Convegno]
Boccolari, Mauro; Guerrieri, Lorenzo; Parmiggiani, Flavio
abstract

Climate datasets derived from satellite images represent the most useful sources for monitoring and investigating present and (short) past climate, in order to understand the climate change evolution. In this work, a subset of AMSR-E and AMSR-2 Sea Ice Concentration (SIC) data set retrieved from the archive of the Institute of Environmental Physics (IEP) of the University of Bremen, is investigated in order to assess the variability and a possible significant trend of sea ice area over the East Greenland Sea during the period 2003 – 2013. The target area goes, approximately, from 60 to 85N and from 45W to 20E. The analysis sho ws that the strong decline of Arctic sea-ice extent in the last 10 years is not observed in the Greenland Sea, suggesting that large reductions have occurred in the Canadian and Russian Arctic. Similar preliminary investigations over West Greenland Sea and Bering Sea are being carried out. Besides, for approximately the same period and target area, ATOVS tropospheric humidity and temperature fields and AVHRR fractional clouds cover (CFC) datasets have been collected from the Satellite Application Facility on Climate Monitoring (CM-SAF), to perform and analyze the correlation with sea ice area. As expected, results show a high anti-correlation between air temperature (and also tropospheric humidity) with observed sea ice area.


2014 - Sea-ice distribution and variability in the East Greenland Sea, 2003-13 [Relazione in Atti di Convegno]
Boccolari, Mauro; Guerrieri, Lorenzo; Parmiggiani, Flavio
abstract

This study presents an analysis of the sea-ice area time series for the East Greenland Sea for the period January 2003 – December 2013. The data used are a subset of the Arctic Sea Ice Concentration data set derived from the observations of the passive microwave sensors AMSR-E and AMSR-2 and produced, on a daily basis, by the Inst. of Environ. Physics of the University of Bremen. The area of interest goes, approximately, from 57◦N to 84◦N and from 53◦W to 15◦E. On the basis of previous studies, the parameter Sea Ice Area as the sum of all pixels whose sea ice concentration is above 70%, was introduced for measuring sea-ice extent. A first survey of the Greenland Sea data set showed a large anomaly in year 2012; this anomaly, clearly linked with the transition period from AMSR-E to AMSR-2 when re-sampled SSM/I data were used, was partially corrected with a linear regression procedure. The correlation between monthly mean Sea Ice Area and other geophysical parameters, like air temperature, surface wind and cloud cover, was further investigated. High anti-correlation coefficients between air temperature, at sea level and in five different tropospheric layers, and observed ice cover is confirmed. Our analysis shows that the strong decline of Arctic sea-ice area in the last 10 years is not observed in the East Greenland Sea; this implies that large reductions have occurred in the Canadian and Russian Arctic. This result confirms a hypothesis recently postulated to explain the different sea-ice decline in the Arctic and Antarctic regions.


2013 - A new simplified approach for simultaneous retrieval of SO2 and ash content of tropospheric volcanic clouds: an application to the Mt Etna volcano [Articolo su rivista]
Pugnaghi, Sergio; Guerrieri, Lorenzo; Corradini, Stefano; L., Merucci; Arvani, Barbara
abstract

A new procedure is presented for simultaneous estimation of SO2 and ash abundance in a volcanic plume, using thermal infrared (TIR) MODIS data. Plume altitude and temperature are the only two input parameters required to run the procedure, while surface emissivity, temperature, atmospheric profiles, ash optical properties, and radiative transfer models are not necessary to perform the atmospheric corrections. The procedure gives the most reliable results when the surface under the plume is uniform, for example above the ocean, but still produces fairly good estimates in more challenging and not easily modelled conditions, such as above land or meteorological cloud layers. The developed approach was tested on the Etna volcano. By linearly interpolating the radiances surrounding a detected volcanic plume, the volcanic plume removal (VPR) procedure described here computes the radiances that would have been measured by the sensor in the absence of a plume, and reconstructs a new image without plume. The new image and the original data allow computation of plume transmittance in the TIR-MODIS bands 29, 31, and 32 (8.6, 11.0 and 12.0 μm) by applying a simplified model consisting of a uniform plume at a fixed altitude and temperature. The transmittances are then refined with a polynomial relationship obtained by means of MODTRAN simulations adapted for the geographical region, ash type, and atmospheric profiles. Bands 31 and 32 are SO2 transparent and, from their transmittances, the effective ash particle radius (Re), and aerosol optical depth at 550 nm (AOD550) are computed. A simple relation between the ash transmittances of bands 31 and 29 is demonstrated and used for SO2 columnar content (cs) estimation. Comparing the results of the VPR procedure with MODTRAN simulations for more than 200 000 different cases, the frequency distribution of the differences shows the following: the Re error is less than ±0.5 μm in more than 60% of cases; the AOD550 error is less than ±0.125 in 80% of cases; the cs error is less than ±0.5 gm−2 in more than 60% of considered cases. The VPR procedure was applied in two case studies of recent eruptions occurring at the Mt Etna volcano, Italy, and successfully compared with the results obtained from the established SO2 and ash assessments based on look-up tables (LUTs). Assessment of the sensitivity to the plume altitude uncertainty is also made. The VPR procedure is simple, extremely fast, and can be adapted to other ash types and different volcanoes.


2010 - ASI-SRV optical sensor data processing modules [Relazione in Atti di Convegno]
M., Musacchio; M., Silvestri; C., Spinetti; S., Corradini; V., Lombardo; L., Merucci; M. F., Buongiorno; S., Perelli; V., Santacesaria; Pugnaghi, Sergio; Gangale, Gabriele; Guerrieri, Lorenzo; Teggi, Sergio
abstract

The Project called Sistema Rischio Vulcanico (SRV) is funded by the Italian Space Agency (ASI) in the frame of the National Space Plan 2003-2005 under the Earth Observations section for natural risks management. The SRV Project is coordinated by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) which is responsible at national level for the volcanic monitoring. The main goal of the SRV project is to define, develop and demonstrate tools and products, based on the EO data, to support the risk management decision procedures. This is achieved through the development of data processing modules dedicated to the generation of specific products and to the dissemination of the information to the end-users in a form suitable for decision making. An important step of the project development regards the technical and scientific feasibility of the provided products.


2008 - ETNA 2003 FIELD CAMPAIGN: CALIBRATION AND VALIDATION OF SPACEBORNE AND AIRBORNE INSTRUMENTS FOR VOLCANIC APPLICATIONS [Articolo su rivista]
M. F., Buongiorno; S., Amici; L., Colini; G., Di Stefano; F., Doumaz; V., Lombardo; M., Musacchio; L., Merucci; M. I., Pannaccione Apa; C., Spinetti; T., Caltabiano; B., Behncke; M., Burton; N., Bruno; S., Giammanco; V., Longo; F., Murè; M., Neri; G., Salerno; B., Badalamenti; I. S., Diliberto; M., Liotta; P., Madonna; M., Silvestri; Pugnaghi, Sergio; Corradini, Stefano; Guerrieri, Lorenzo; Lombroso, Luca; Teggi, Sergio; Remitti, Matteo; G. P., Gobbi; F., Barnaba; M., Sgavetti; L., Pompilio; V., Tramutoli; V., Lanorte; N., Pergola; F., Marchese; G., Di Bello; O., Candela; E., Lindermeier; P., Haschberger; V., Tank; D., Oertel; H., Kick; N., Santantonio; M., Mannarella; M. P., Bogliolo
abstract

The field measurements campaign madein July 2003 on Etna, Vulcano Island and CampiFlegrei was dedicated to the calibration and validationof airborne and spaceborne data. Thecampaign activities were relevant part of twoASI funded projects:1) FASA, dedicated to airborne system and datavalidation/calibration2) HypSEO, dedicated to multispectral anhyperspectral spaceborne datavalidation/calibration on specific test areas.The airborne campaign was organized inthe frame of a three-year project funded by ASIand DLR as it represented the flight test of theFASA system, which combines a Fourier interferometerin the MIR-TIR region and an imager(ABAS).The main objectives of this proposal are:1. Design and implementation of an airbornesystem for the Fourier Spectrometer MIRORand ABAS (Bird Airborne Simulator);2. Airborne Operational tests of the FASAsystem over the main Italian volcanic areas(i.e. Etna, Stromboli and Vulcano) and possiblyon controlled forest fires (Germany);3. Organization of the necessary ground campaignfor calibration and validation of theacquired data;4. Development of the algorithms for the selectionof the “spectral windows” and for thedetermination of the presence of some gasses:in particular SO2, CO2, H2S and othergasses of volcanic origin.


2007 - AN AEROSOL OPTICAL THICKNESS RETRIEVAL ALGORITHM FOR METEOSAT SECOND GENERATION (MSG) DATA OVER LAND: APPLICATION IN THE MEDITERRANEAN AREA [Abstract in Atti di Convegno]
Guerrieri, Lorenzo; Corradini, Stefano; Pugnaghi, Sergio; Santangelo, Renato
abstract

The Spinning Enhanced Visible and Infra Red Imager (SEVIRI) radiometer, on board on Meteosat Second Generation(MSG) geostationary satellite, collects, each 15 minutes, images of the underneath part of the globe in 12 spectral bandswith a spatial resolution of 3 km. In this work the Aerosol Optical Thickness (AOT) retrieval over land using SEVIRIdata is presented. AOT at 0.55 μm is estimated minimizing the difference between measured and computed radiances inthe visible channel centered at 0.6 μm by means Look-Up Tables (LUT) obtained using 6S radiative transfer code. The0.6 μm surface reflectance has been computed using different procedures based on SEVIRI channels 3 and 4 centeredrespectively around 1.6 and 3.9 μm. For the 0.6 μm surface reflectance retrieval using the 1.6 μm procedure, themeasurements of five automatic sun-photometers of the Aerosols Robotic Network (AERONET) located in theMediterranean area (Avignon, Laegeren, Modena, Rome and Lecce) has been used. The procedures show encouragingresults in case of 1.6 μm procedure retrieval and the inadequacy of 3.9 μm procedure. An AOT map of the Po Valley(Italy), obtained from an MSG image taken during a typical winter polluted day, is shown in the paper and comparedwith MODIS retrieval.


2004 - ONE YEAR OF AERONET SUN-PHOTOMETRIC MEASUREMENTS AT LAMPEDUSA SITE: MONTHLY AVERAGED AOT COMPARISON WITH SATELLITE DATA AND SAHARAN DUST EVENTS DETECTION [Articolo su rivista]
Corradini, Stefano; E., Carboni; Guerrieri, Lorenzo; Lombroso, Luca; Pugnaghi, Sergio; R., Santangelo
abstract

Not available