1,513 research outputs found

    Does the Danube exist? Versions of reality given by various regional climate models and climatological datasets

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    We present an intercomparison and verification analysis of several regional climate models (RCMs) nested into the same run of the same Atmospheric Global Circulation Model (AGCM) regarding their representation of the statistical properties of the hydrological balance of the Danube river basin for 1961-1990. We also consider the datasets produced by the driving AGCM, from the ECMWF and NCEP-NCAR reanalyses. The hydrological balance is computed by integrating the precipitation and evaporation fields over the area of interest. Large discrepancies exist among RCMs for the monthly climatology as well as for the mean and variability of the annual balances, and only few datasets are consistent with the observed discharge values of the Danube at its Delta, even if the driving AGCM provides itself an excellent estimate. Since the considered approach relies on the mass conservation principle and bypasses the details of the air-land interface modeling, we propose that the atmospheric components of RCMs still face difficulties in representing the water balance even on a relatively large scale. Their reliability on smaller river basins may be even more problematic. Moreover, since for some models the hydrological balance estimates obtained with the runoff fields do not agree with those obtained via precipitation and evaporation, some deficiencies of the land models are also apparent. NCEP-NCAR and ERA-40 reanalyses result to be largely inadequate for representing the hydrology of the Danube river basin, both for the reconstruction of the long-term averages and of the seasonal cycle, and cannot in any sense be used as verification. We suggest that these results should be carefully considered in the perspective of auditing climate models and assessing their ability to simulate future climate changes.Comment: 25 pages 8 figures, 5 table

    Ferramenta para integração de dados de recursos naturais dos biomas brasileiros.

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    O projeto NATDATA, sigla para Plataforma de Integração de Dados dos Recursos Naturais (MACÁRIO et al., 2011) tem como um de seus objetivos criar uma interface para o usuário final das informações sobre os recursos naturais dos biomas brasileiros, ajudando-o com um ambiente intuitivo que permita a consulta rápida e integrada a esses dados. Essa consulta permitirá que haja uma melhor orientação dos investimentos, como uma visão antecipada dos possíveis problemas que alguma região possa sofrer. Devido ao modo heterogêneo com que diversas instituições brasileiras colheram essas informações, há uma grande dificuldade em reaproveitá-las em conjunto. Com isso, o projeto NATDATA foca centralizar essa informação, tornando-a utilizável

    Sistema interativo de suporte ao licenciamento ambiental e sua integração com sistemas locais via Serviços Web.

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    Este trabalho descreve brevemente as ferramentas disponibilizadas pelo Sistema Interativo de Suporte ao Licenciamento Ambiental (Sisla), um sistema desenvolvido para auxiliar governos estaduais na tomada de decisão quanto ao licenciamento ambiental, apresentando, principalmente, como realizar a sua integração com sistemas locais que controlam o fluxo de processos de licenciamento ambiental. Como caso de uso, foi utilizado o Sistema Imasul de Registros e Informações Estratégicas do Meio Ambiente (Siriema) (SIRIEMA..., 2010), no âmbito do Estado de Mato Grosso do Sul. A principal contribuição deste trabalho é demonstrar a facilidade de integração do Sisla com qualquer sistema que controle o fluxo de processos no âmbito estadual ou municipal via Serviços Web, independente do ambiente de programação e sistema operacional em que forem desenvolvidos.bitstream/item/32398/1/ComTec103.pd

    Ferramenta computacional para auxílio à análise técnica de processos de licenciamento ambiental utilizando geotecnologias.

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    Este trabalho descreve a elaboração de uma ferramenta computacional para auxílio à análise técnica de processos de licenciamento ambiental, com o uso de geotecnologias. Essa ferramenta constitui mais um módulo do Sistema Iterativo de Suporte ao Licenciamento Ambiental ? SISLA e está em fase de testes pelos técnicos do Instituto de Meio Ambiente de Mato Grosso do Sul (Imasul). Para o desenvolvimento desse módulo, foram utilizadas ferramentas já bastante difundidas no campo das geotecnologias e computação, como o I3Geo/MapServer, linguagem de programação PHP e banco de dados PostgreSQL com extensão espacial (PostGIS). A grande vantagem de sua utilização se dá pelo fato de todas as áreas mapeadas para o processo de licenciamento ambiental em questão serem carregadas ao mesmo tempo. Além disso, outros temas disponíveis no SISLA também podem ser carregados em conjunto com esses mapas, possibilitando ao técnico visualizar a existência de áreas protegidas pelo governo próximas ou até mesmo que avançam na área da propriedade ou do projeto de licenciamento. Em trabalhos futuros, pretende-se agregar a esse módulo uma ferramenta para auxílio à tomada de decisão para gestão e monitoramento de regularização ambiental, com base nas leis e resoluções definidas pelo governo.Geopantanal 2010

    Adaptação de ferramenta de relatório geoespacial para Zoneamento Ecológico-Econômico da Amazônia Legal.

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    A ferramenta "relatório", objeto deste trabalho, foi programada originalmente para realizar consultas de terras particulares no Mato Grosso do Sul, via um sistema de informação geográfica web chamado Sistema Interativo de Suporte ao Licenciamento Ambiental (Sisla). O objetivo deste trabalho é adaptá-la para uma função similar no Projeto de Zoneamento Ecológico-Econômico da Amazônia Legal (ZEEAL)

    Magnetic fabric of Pleistocene continental clays from the hanging-wall of an active low-angle normal fault (Altotiberina Fault, Italy)

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    Anisotropy of magnetic susceptibility (AMS) represents a valuable proxy able to detect subtle strain effects in very weakly deformed sediments. During the last decades a large number of AMS studies have documented that in compressive tectonic settings the maximum susceptibility axes (i.e. the magnetic lineations) are parallel to fold axes (and thrust faults) and local bedding strikes, while in extensional regimes they are perpendicular to the normal faults and, thus, parallel to the strata dip directions. One of the most striking active tectonic structures of the northern Apennines is represented by the Altotiberina Fault (ATF), a NE-dipping low-angle normal fault bounding the High Tiber Valley. The ATF represents a primary detachment of the Plio-Quaternary extensional tectonics affecting the Apennine belt. The long-lasting activity of the ATF produced 5 km of total displacement and up to 1200-m-thick basin infill of syn-tectonic, sandy-clayey continental succession. Thus, the AMS analysis of the sediments lying above the ATF represents a unique opportunity to document the strain field affecting the hanging-wall of low-angle normal faults. We collected 129 oriented cores at 12 different localities within the High Tiber Valley, and measured the AMS with a spinner Multi-Function Kappabridge. Most of the sites show a magnetic fabric typical of sediments at the earliest stages of deformation, characterized by oblate AMS ellipsoids and a well defined magnetic lineation, while prolate AMS ellipsoids at two sites are suggestive of pervasive tectonic effects. The magnetic lineation is well-developed at all sites and 20 has a prevailing N-S direction. At five sites the bedding is tilted and the magnetic lineation is subparallel to local bed-strikes, implying that these sites underwent a maximum horizontal shortening along an E-W direction. At two sites the magnetic lineation is sub-perpendicular to the trend of the ATF, and may be related to extensional strain. Our results reveal the existence of both compressional and extensional structures at the hangingwall of the ATF, and suggest that the early Pleistocene sequence of the High Tiber Valley is arranged in gently, local folds (hardly visible in the field) ~N-S trending. We interpret these compressivestructures as the result of local superficial stress induced by irregularities of the fault plane at depth. Accordingly, the strain field we documented from the High Tiber Valley can not be used to infer the regional tectonic regime acting during the ATF activity. We conclude that the long-lasting debate on the extensional vs. compressional Plio-Quaternary tectonics of the Apennines orogenic belt should be revised evaluating the importance of compressional structures resulting by local effects

    Magnetic fabric of Pleistocene continental clays from the hanging-wall of an active low-angle normal fault (Altotiberina Fault, Italy)

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    Anisotropy of magnetic susceptibility (AMS) represents a valuable proxy able to detect subtle strain effects in very weakly deformed sediments. In compressive tectonic settings, the magnetic lineation is commonly parallel to fold axes, thrust faults, and local bedding strike, while in extensional regimes, it is perpendicular to normal faults and parallel to bedding dip directions. The Altotiberina Fault (ATF) in the northern Apennines (Italy) is a Plio-Quaternary NNW–SSE low-angle normal fault; the sedimentary basin (Tiber basin) at its hanging-wall is infilled with a syn-tectonic, sandy-clayey continental succession. We measured the AMS of apparently undeformed sandy clays sampled at 12 sites within the Tiber basin. The anisotropy parameters suggest that a primary sedimentary fabric has been overprinted by an incipient tectonic fabric. The magnetic lineation is well developed at all sites, and at the sites from the western sector of the basin it is oriented sub-perpendicular to the trend of the ATF, suggesting that it may be related to extensional strain. Conversely, the magnetic lineation of the sites from the eastern sector has a prevailing N–S direction. The occurrence of triaxial to prolate AMS ellipsoids and sub-horizontal magnetic lineations suggests that a maximum horizontal shortening along an E–W direction occurred at these sites. The presence of compressive AMS features at the hanging-wall of the ATF can be explained by the presence of gently N–Strending local folds (hardly visible in the field) formed by either passive accommodation above an undulated fault plane, or rollover mechanism along antithetic faults. The long-lasting debate on the extensional versus compressive Plio-Quaternary tectonics of the Apennines orogenic belt should now be revised taking into account the importance of compressive structures related to local effects

    Verification of Precipitation Forecasts from Two Limited-Area Models over Italy and Comparison with ECMWF Forecasts Using a Resampling Technique

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    Abstract This paper presents the first systematic limited area model (LAM) precipitation verification work over Italy. A resampling technique was used to provide skill score results along with confidence intervals. Two years of data were used, starting in October 2000. Two operational LAMs have been considered, the Limited Area Model Bologna (LAMBO) operating at the Agenzia Regionale Prevenzione e Ambiente-Servizio Meteorologico Regionale (ARPA-SMR) of the Emilia–Romagna region, and the QUADRICS Bologna Limited Area Model (QBOLAM) running at the Agenzia per la Protezione dell'Ambiente e per i Servizi Tecnici (APAT). A 24-h forecast skill score comparison was first performed on the native 0.1° high-resolution grids, using a Barnes scheme to produce the observed 24-h accumulated rainfall analysis. Two nonparametric skill scores were used: the equitable threat score (ETS) and the Hanssen and Kuipers score (HK). Frequency biases (BIA) were also calculated. LAM forecasts were also remapped on a lower-resolution grid (0.5°), using a nearest-neighbor average method; this remapping allowed for comparison with ECMWF model forecasts, and for LAM intercomparisons at lower resolution, with the advantage of reducing the skill score sensitivity to small displacements errors. LAM skill scores depend on the resolution of the verification grid, with an increase when they are verified on a lower-resolution grid. The selected LAMs have a higher BIA compared to ECMWF, showing a tendency to overforecast precipitation, especially along mountain ranges, possibly due to undesired effects from the large-scale and/or convective precipitation parameterizations. Lower ECMWF BIA accounts for skill score differences. LAMBO precipitation forecasts during winter (adjusted for BIA differences) have less misses than ECMWF over the islands of Sardinia and Sicily. Higher-resolution orography definitely adds value to LAM forecasts
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