1,338 research outputs found
Coupling a distributed grid based hydrological model and MM5 meteorological model for flooding alert mapping
International audienceThe increased number of extreme rainfall events seems to be one of the common feature of climate change signal all over the world (Easterlin et al., 2000; Meehl et al., 2000). In the last few years a large number of floods caused by extreme meteorological events has been observed over the river basins of Mediterranean area and they mainly affected small basins (few hundreds until few thousands of square kilometres of drainage area) . A strategic goal of applied meteorology is now to try to predict with high spatial resolution the segments of drainage network where floods may occur. A possible way to reach this aim is the coupling of meteorological mesoscale model with high resolution hydrological model. In this work few case studies of observed floods in the Italian Mediterranean area will be presented. It is shown how a distributed hydrological model, using the precipitation fields predicted by MM5 meteorological model, is able to highlight the area where the major floods may occur
Artificial neural-network technique for precipitation nowcasting from satellite imagery
The term nowcasting reflects the need of timely and accurate predictions of risky situations related to the development of severe meteorological events. In this work the objective is the very short term prediction of the rainfall field from geostationary satellite imagery entirely based on neural network approach. The very short-time prediction (or nowcasting) process consists of two steps: first, the infrared radiance field measured from geostationary satellite (Meteosat 7) is projected ahead in time (30 min or 1 h); secondly, the projected radiances are used to estimate the rainfall field by means of a calibrated microwave-based combined algorithm. The methodology is discussed and its accuracy is quantified by means of error indicators. An application to a satellite observation of a rainfall event over Central Italy is finally shown and evaluated
Thermally driven circulation in a region of complex topography: comparison of wind-profiling radar measurements and MM5 numerical predictions
The diurnal variation of regional wind patterns in the complex terrain of Central Italy was investigated for summer fair-weather conditions and winter time periods using a radar wind profiler. The profiler is located on a site where interaction between the complex topography and land-surface produces a variety of thermally and dynamically driven wind systems. The observational data set, collected for a period of one year, was used first to describe the diurnal evolution of thermal driven winds, second to validate the Mesoscale Model&nbsp;5 (MM5) that is a three-dimensional numerical model. This type of analysis was focused on the near-surface wind observation, since thermally driven winds occur in the lower atmosphere. According to the valley wind theory expectations, the site &ndash; located on the left sidewall of the valley (looking up valley) &ndash; experiences a clockwise turning with time. Same characteristics in the behavior were established in both the experimental and numerical results. <P style="line-height: 20px;"> Because the thermally driven flows can have some depth and may be influenced mainly by model errors, as a third step the analysis focuses on a subset of cases to explore four different MM5 Planetary Boundary Layer (PBL) parameterizations. The reason is to test how the results are sensitive to the selected PBL parameterization, and to identify the better parameterization if it is possible. For this purpose we analysed the MM5 output for the whole PBL levels. The chosen PBL parameterizations are: 1) Gayno-Seaman; 2) Medium-Range Forecast; 3) Mellor-Yamada scheme as used in the ETA model; and 4) Blackadar
Cancer incidence in eastern Libya: The first report from the Benghazi Cancer Registry, 2003
Cancer registration in Northern Africa is still limited and, until now, there have been no population-based data available for Libya. In this paper, we present the first data collected and analyzed by the Benghazi Cancer Registry. Registration was carried out by active data collection; the registry staff routinely visited all hospitals and pathological laboratories in eastern Libya (1.6 million inhabitants) and collected information from all death registration offices. A huge archive of prevalent cases was established before the 2003 data were collected. A total of 997 cases of primary cancers were registered among residents in 2003. The world age-standardized incidence rate for all sites combined (except non-melanoma skin) was 118 per 100,000 for men and 95 per 100,000 for women. The most frequently diagnosed malignancies in males were lung cancer (19%) and colorectal cancer (10%), followed by cancers of the head and neck (9%) and bladder (9%). Among females, they were breast cancer (26%), cancer of the colon and rectum (9%), uterus (7%) and non-Hodgkin lymphoma (5%). Our study provides data on cancer incidence in eastern Libya, and confirms that cancer incidence is much lower than in western countries. Moreover, observed patterns indicate that the incidence of many cancers, including those of the lung, breast, colon, rectum and bladder is quite different from previous estimates based on the data available from the neighboring countries. (c) 2006 Wiley-Liss, Inc
Identification of Source Faults of Large Earthquakes in the TurkeyâSyria Border Region Between 1000 CE and the Present, and Their Relevance for the 2023 Mw 7.8 Pazarcık Earthquake
The 6 February 2023, Mw 7.8 Pazarcık earthquake in the Turkey-Syria border region raises the question of whether such a large earthquake could have been foreseen, as well as what is the maximum possible magnitude (Mmax) of earthquakes on the East Anatolian Fault (EAF) system and on continental transform faults in general. To answer such questions, knowledge of past earthquakes and of their causative faults is necessary. Here, we integrate data from historical seismology, paleoseismology, archeoseismology, and remote sensing to identify the likely source faults of fourteen Mw ℠7 earthquakes between 1000 CE and the present in the region. We find that the 2023 Pazarcık earthquake could have been foreseen in terms of location (the EAF) and timing (an earthquake along this fault was if anything overdue), but not magnitude. We hypothesize that the maximum earthquake magnitude for the EAF is in fact 8.2, that is, a single end-to-end rupture of the entire fault, and that the 2023 Pazarcık earthquake did not reach Mmax by a fortuitous combination of circumstances. We conclude that such unusually large events are hard to model in terms of recurrence intervals, and that seismic hazard assessment along continental transforms cannot be done on individual fault systems but must include neighboring systems as well, because they are not kinematically independent at any time scale
Direct Evidence of a SlowâSlip Transient Modulating the Spatiotemporal and FrequencyâMagnitude Earthquake Distribution: Insights From the Armutlu Peninsula, Northwestern Turkey
Earthquakes and slowâslip events interact, however, detailed studies investigating their interplay are still limited. We generate the highest resolution microseismicity catalog to date for the northern Armutlu Peninsula in a âŒ1âyear period to perform a detailed seismicity distribution analysis and correlate the results with a local, geodetically observed slowâslip transient within the same period. Seismicity shows a transition of clusterâtype behavior from swarmâlike to burstâlike, accompanied by an increasing relative proportion of clustered (nonâPoissonian) relative to background (Poissonian) seismicity and gradually decreasing bâvalue as the geodetically observed slowâslip transient ends. The observed slowâslip transient decay correlates with gradually increasing effectiveâstressâdrop values. The observed correlation between the bâvalue and geodetic transient highlights the influence of aseismic deformation on seismic deformation and the impact of slowâslip transients on local seismic hazard
Serial assessment of the electrocardiographic strain pattern for prediction of newâonset heart failure during antihypertensive treatment: the LIFE study
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106144/1/ejhfhfq224.pd
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