1,721,030 research outputs found
Recent snow cover variability in the Italian Alps
No full textThe historical record of snow duration (from 1950 to 2009) and of snowfall (from 1960 to 2009) collected in the Italian Alps are presented and analysed. A reduction of the snow cover duration and of the snowfall stronger in springtime was detected during the last 40 years with the greatest decreasing rate during the 1990s. The last decade is characterised by a recovery from the documented decreasing trend mainly evident between 800 m and 1500 m. Principal component trend analysis of the snow duration and of the snowfall showed a long term decreasing trend. The change point test showed the existence of breakpoints between 1984 and 1994 that characterise the snow duration and snowfall time series analysed by elevation range and by seasons. These breakpointsmark a drastic trend variability in the time series: a positive trend characterises the time series before the breakpoint and a decreasing trend characterises the historical record after the breakpoint. The described negative trends result from the documented decrease in winter and spring precipitation. This in turn may either relate to a change in fraction of liquid to solid precipitation, and/or be associated to an increase of the temperatures. Northern Hemisphere and Italian Alps snow cover trends strongly correlate in the frequency domain. Among the dominant frequencies the 11.2 period was detected that may relate to the 11-year solar activity cycl
Detecting snow avalanches with seismic stations in North-east Italy: first results of data set analysis
No full textThe Regional Agency for the Environmental Prevention and Protection of Veneto (Agenzia Regionale per la Prevenzione e Protezione Ambientale del Veneto, ARPAV) was established in October 2007 to monitor and prevent environmental risks in the Veneto region, in North-eastern Italy. The Italian National Institute for Oceanography and Experimental Geophysics (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, OGS), after the strong earthquake (magnitude M=6.4) occurred in 1976 in the Friuli-Venezia Giulia region, started to operate the North-east Italy (NI) seismic network: it currently consist of 11 very sensitive broad band and 21 more simple short period seismic stations, all telemetered to and acquired in real time in the Seismological Research Center (Centro di Ricerche Sismologiche, CRS) of the OGS in Udine.
In June 2007 OGS installed in cooperation with the Italian National Institute for Geophysics and Volcanology (Istituto Nazionale di Geofisica e Vulcanologia, INGV) a broad band seismic station in Agordo, a site located in the Dolomites mountains in the Veneto region. During the last 2008/09 winter season, in the whole Dolomites, above the altitude of 1,200m, between 250 and 350 cm of fresh snow have fallen: similar snowfall events occurred in the last 80 years only in 1951, 1959, 1960 and 1979.
The large amount of snow fell failed to consolidate and in the Dolomites, the study area of this work, the spontaneous avalanche phenomena was very intense, with several large avalanches reaching the bottoms of the valleys, and that were also detected by the OGS seismic network: avalanches of such characteristics were not observed since February 1977 and January 1987. In this work we correlate seismic parameters (such recording length) with physical characteristics of the avalanches triggering them (such run-out).UnpublishedDavos, Switzerland4.4. Scenari e mitigazione del rischio ambientaleope
L'eccezionale Stagione Invernale 2008-2009: Caratteristiche, Valanghe e Monitoraggio Sismico
No full textLa stagione invernale 2008 – 2009 è stata nevosa su tutto l’arco alpino meridionale
nelle Dolomiti, con lunghi periodi perturbati, consistenti apporti di neve fresca,
con una attività valanghiva frequente.
Nelle Dolomiti è anche presente una stazione sismica a larga banda, alta dinamica
e alta sensibilità, installata nelle dell’Istituto Minerario U.Follador di Agordo.
Il presente lavoro, dopo aver presentato le caratteristiche essenziali della stagione
invernale, illustra la perturbazione sismica generata dall’attività valanghiva
e registrata dal sismometro di Agordo e della rete sismica gestita dall’OGS nel
Nord-est Italia.
La ricerca e l’individuazione di tali segnali inizialmente sulla base di valanghe note,
possono contribuire ad individuare delle metodologie di analisi tali da poter ricostruire
l’attività valanghiva avvenuta nell’area adiacente i sismometri.
Le tracce sismiche registrate dalla stazione di Agordo con caratteristiche tipiche
del movimento delle valanghe, hanno permesso di ricostruire i periodi di attività
valanghiva dando un valido supporto alla verifica dei vari bollettini di pericolo da
valanghe emessi nelle aree adiacenti. La ricerca condotta con questo lavoro suggerisce
di installare una rete sismica più densa dedicata, anche in maniera temporanea,
al rilevamento di valanghe.Published6-174.4. Scenari e mitigazione del rischio ambientaleN/A or not JCRope
Detecting Avalanches with Seismic Stations in North-east Italy: First Results of Dataset Analysis
No full textThe Regional Agency for the Environmental Prevention and Protection of Veneto (Agenzia Regionale per la Prevenzione e Protezione Ambientale del Veneto, ARPAV) was established in October 2007 to monitor and prevent environmental risks in the Veneto region, in North-eastern Italy. The Italian National Institute for Oceanography and Experimental Geophysics (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, OGS), after the strong earthquake (magnitude M=6.4) occurred in 1976 in the Friuli-Venezia Giulia region, started to operate the North-east Italy (NI) seismic network: it currently consist of 10 very sensitive broad band and 21 more simple short period seismic stations, all telemetered to and acquired in real time in the Seismological Research Center (Centro di Ricerche Sismologiche, CRS) of the OGS in Udine.
In June 2007 OGS installed in cooperation with the Italian National Institute for Geophysics and Volcanology (Istituto Nazionale di Geofisica e Vulcanologia, INGV) a broad band seismic station in Agordo, a site located in the Dolomites mountains in the Veneto region. During the 2008-2009 winter season, in the whole Dolomites, above the altitude of 1,200m, between 250 and 350 cm of fresh snow have fallen: similar snowfall events occurred in the last 80 years only in 1951, 1959, 1960 and 1979.
The large amount of snow fell failed to consolidate and in the Dolomites, the study area of this work, the spontaneous avalanche phenomena was very intense, with several large avalanches reaching the bottoms of the valleys, and that were also detected by the OGS seismic network: avalanches of such characteristics were not observed since February 1977 and January 1987. In this work we correlate seismic parameters (such recording length) with physical characteristics of the avalanches triggering them (such runout).Submitted4.4. Scenari e mitigazione del rischio ambientaleJCR Journalope
Recent snow cover variations and avalanche activities in the Southern Alps
No full textSnow and albedo play a significant role in the planet's radiation balance. Snow cover extension, of the Northern Hemisphere in the last forty years, generally decreased causing direct and indirect feedback both on climate and atmospheric circulation. Up-to-date available data on seasonal snow cover trend are scarce and limited to few nations. Few European studies in the Northern Alps highlighted a decrease in snow cover duration and an increase of its elevation for tourism purposes. Using the data of more than 60 sites located in the Southern Alps a first budget of the recent snow cover trend has been outlined. Compared to the 1961-90 mean value, the average snow cover duration decreased of about 14 days, with a major influence on elevations lower than 1600 metres. Seasonal snow precipitation accumulation has been decreasing, at all elevations, since 1990. Winter 2008-2009 was the 3rd or 4th more snowy season since 1930. During this winter spontaneous avalanche activity was frequent and extreme avalanches often detached. The 2008-2009 winter daily observation data of several sites located in the Southern Alps were used to find interconnections between recent snow cover variations, spontaneous avalanche activity and avalanche accidents
L'eccezionale Stagione Invernale 2008-2009: Caratteristiche, Valanghe e Monitoraggio Sismico
No full textLa stagione invernale 2008 – 2009 è stata nevosa su tutto l’arco alpino meridionale
nelle Dolomiti, con lunghi periodi perturbati, consistenti apporti di neve fresca,
con una attività valanghiva frequente.
Nelle Dolomiti è anche presente una stazione sismica a larga banda, alta dinamica
e alta sensibilità, installata nelle dell’Istituto Minerario U.Follador di Agordo.
Il presente lavoro, dopo aver presentato le caratteristiche essenziali della stagione
invernale, illustra la perturbazione sismica generata dall’attività valanghiva
e registrata dal sismometro di Agordo e della rete sismica gestita dall’OGS nel
Nord-est Italia.
La ricerca e l’individuazione di tali segnali inizialmente sulla base di valanghe note,
possono contribuire ad individuare delle metodologie di analisi tali da poter ricostruire
l’attività valanghiva avvenuta nell’area adiacente i sismometri.
Le tracce sismiche registrate dalla stazione di Agordo con caratteristiche tipiche
del movimento delle valanghe, hanno permesso di ricostruire i periodi di attività
valanghiva dando un valido supporto alla verifica dei vari bollettini di pericolo da
valanghe emessi nelle aree adiacenti. La ricerca condotta con questo lavoro suggerisce
di installare una rete sismica più densa dedicata, anche in maniera temporanea,
al rilevamento di valanghe.Published6-174.4. Scenari e mitigazione del rischio ambientaleN/A or not JCRope
Detecting snow avalanches with seismic stations in North-east Italy: first results of data set analysis
No full textThe Regional Agency for the Environmental Prevention and Protection of Veneto (Agenzia Regionale per la Prevenzione e Protezione Ambientale del Veneto, ARPAV) was established in October 2007 to monitor and prevent environmental risks in the Veneto region, in North-eastern Italy. The Italian National Institute for Oceanography and Experimental Geophysics (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, OGS), after the strong earthquake (magnitude M=6.4) occurred in 1976 in the Friuli-Venezia Giulia region, started to operate the North-east Italy (NI) seismic network: it currently consist of 11 very sensitive broad band and 21 more simple short period seismic stations, all telemetered to and acquired in real time in the Seismological Research Center (Centro di Ricerche Sismologiche, CRS) of the OGS in Udine.
In June 2007 OGS installed in cooperation with the Italian National Institute for Geophysics and Volcanology (Istituto Nazionale di Geofisica e Vulcanologia, INGV) a broad band seismic station in Agordo, a site located in the Dolomites mountains in the Veneto region. During the last 2008/09 winter season, in the whole Dolomites, above the altitude of 1,200m, between 250 and 350 cm of fresh snow have fallen: similar snowfall events occurred in the last 80 years only in 1951, 1959, 1960 and 1979.
The large amount of snow fell failed to consolidate and in the Dolomites, the study area of this work, the spontaneous avalanche phenomena was very intense, with several large avalanches reaching the bottoms of the valleys, and that were also detected by the OGS seismic network: avalanches of such characteristics were not observed since February 1977 and January 1987. In this work we correlate seismic parameters (such recording length) with physical characteristics of the avalanches triggering them (such run-out).UnpublishedDavos, Switzerland4.4. Scenari e mitigazione del rischio ambientaleope
Detecting Avalanches with Seismic Stations in North-east Italy: First Results of Dataset Analysis
No full textThe Regional Agency for the Environmental Prevention and Protection of Veneto (Agenzia Regionale per la Prevenzione e Protezione Ambientale del Veneto, ARPAV) was established in October 2007 to monitor and prevent environmental risks in the Veneto region, in North-eastern Italy. The Italian National Institute for Oceanography and Experimental Geophysics (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, OGS), after the strong earthquake (magnitude M=6.4) occurred in 1976 in the Friuli-Venezia Giulia region, started to operate the North-east Italy (NI) seismic network: it currently consist of 10 very sensitive broad band and 21 more simple short period seismic stations, all telemetered to and acquired in real time in the Seismological Research Center (Centro di Ricerche Sismologiche, CRS) of the OGS in Udine.
In June 2007 OGS installed in cooperation with the Italian National Institute for Geophysics and Volcanology (Istituto Nazionale di Geofisica e Vulcanologia, INGV) a broad band seismic station in Agordo, a site located in the Dolomites mountains in the Veneto region. During the 2008-2009 winter season, in the whole Dolomites, above the altitude of 1,200m, between 250 and 350 cm of fresh snow have fallen: similar snowfall events occurred in the last 80 years only in 1951, 1959, 1960 and 1979.
The large amount of snow fell failed to consolidate and in the Dolomites, the study area of this work, the spontaneous avalanche phenomena was very intense, with several large avalanches reaching the bottoms of the valleys, and that were also detected by the OGS seismic network: avalanches of such characteristics were not observed since February 1977 and January 1987. In this work we correlate seismic parameters (such recording length) with physical characteristics of the avalanches triggering them (such runout).Submitted4.4. Scenari e mitigazione del rischio ambientaleJCR Journalope
Occurrence of PAH in the seasonal snowpack of the Eastern Italian Alps
No full textPAH concentrations have been determined in 47 seasonal snowpack samples collected in the Valbelluna
valley and in the Bellunesi Dolomites National Park, in the Italian North-Eastern Alps, during the winter
of 2005. The sum of PAH concentration in high-altitude alpine sites (above 1700 m) was 32 +- 20 ng/kg while in
valley bottom urban areas it was 165 +- 54 ng/kg with maximum values of 290 ng/kg. The GIS mapping
technique was employed to produce a PAH spatial distribution. The urbanized Valbelluna valley, and in
particular the SW part, had the highest accumulation of all PAH, with values an order of magnitude more
than those in rural and alpine areas. This behaviour is consistent with urban air quality data, and is due to
geo-morphological and meteorological factors such as the deeper shape of the valley at the position of
the town of Feltre and the low altitude of the boundary layer during the winter season
- …
