87 research outputs found

    MODELLING WATER AND ENERGY BALANCE OF THE LAND-ATMOSPHERE SYSTEM USING HIGH RESOLUTION REMOTE SENSING DATA

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    La rilevanza assunta dal risparmio della risorsa idrica negli ultimi anni ha spinto verso una corretta quanti cazione delle perdite legate al processo evapotraspirativo, al ne di una gestione parsimoniosa della risorsa stessa. In particolare nei sistemi agricoli soggetti a stress severo, sia la misura che la stima dell'evapotraspirazione (ET) ad un'adeguata risoluzione spaziale e temporale sono uno dei principali problemi da a rontare per la comunit a scienti ca. Recentemente, le tecniche di telerilevamento sono divenute un ulteriore strumento a supporto della modellistica idrologica distribuita; in particolare, le immagini acquisite nelle onde corte e nell'infrarosso termico risultano essere di notevole interesse. In questo contesto, i due scopi principali di questa ricerca sono stati: la quanti cazione dell'accuratezza delle misure micro-meteorologiche in sistemi agricoli vegetati con colture alte e sparse; e l'analisi dei modelli basati su dati telerilevati per la stima di ET ad alta risoluzione spaziale e temporale. L'area di studio e caratterizzata da un tipico clima Mediterraneo e da colture olivicole, e si trova localizzata nei pressi di Castelvetrano (Italia). Quest'area e stata oggetto nella primavera-estate 2008 di una campagna di misura mediante istallazioni eddy covariance e scintillometrica, e, contestualmente, dall'acquisizione di 7 immagini multi-spettrali ad alta risoluzione. L'analisi delle misure micro-meteorologiche ha permesso di quanti care l'accordo tra le due tecniche e ha portato allo sviluppo di un nuovo approccio di calibrazione dei dati scintillometrici. Inoltre, alcune ipotesi alla base della stima dei ussi giornalieri sono state discusse in dettaglio. L'analisi degli algoritmi per la simulazione dei processi di scambio nel continuo suolo-pianta-atmosfera e stata focalizzata: i) sulle stime hot-spot di ET mediante un approccio di bilancio energetico residuale, ii) sulla stima in continuo di ET alla scala di campo mediante diversi approcci. Quest'ultima analisi ha evidenziato i buoni risultati del modello accoppiato energetico/idrologico per la stima dei ussi di acqua ed energia sia a scala oraria che giornaliera. In ne, l'applicabilit a di due approcci di data assimilation e stata testata utilizzando sia osservazioni arti ciali che reali.In view of the increased relevance of water saving issues in the last decades, the correct quanti cation of water loss due to evapotranspirative process became fundamental for a parsimonious management of this resource. Especially in agricultural systems subjected to severe water stress, both the measurement and the modelling of evapotranspiration (ET) at adequate temporal and spatial resolution, are important topics for the hydrologist scienti c community. Recently, the remote sensing techniques provide an additional tool to support the hydrologic spatially distributed models; in particular, images acquired in the short-wave and the thermal spectral regions have quite interesting applications. Within this framework, the two principal aims of this work were: to quantify the accuracy of surface energy uxes measured by micro-meteorological techniques in sparse tall vegetated system; and to analyze the capability of remote sensing-based approach to retrieve ET at high temporal and spatial resolution. The selected test site was an area characterized by Mediterranean climate and olive crops, located near Castelvetrano (Italy). This area, during the spring-summer period in 2008, was interested by in-situ measurements campaigns with eddy covariance and scintillometer instruments, and, contextually, by the acquisition of 7 high resolution multi-spectral images. The analysis of micro-meteorological measurements allows to evaluate the agreement between these techniques in the study site, also by means of a novel algorithm for the elaboration of scintillometer data. Moreover, some fundamental hypothesis of daily uxes estimation was critically discussed. The analysis of the algorithms for the simulation of the exchange processes in the continuum soil-plant-atmosphere was focused on: i) the retrieval of hot-spot ET maps by means of residual energy balance approach and ii) the continuous ET estimation at eld scale using di erent approaches. This latter analysis highlights the good performance of a coupled energy/hydrological model for the assessment of energy and water uxes at both hourly and daily scale. Finally, the applicability of two data assimilation schemes was tested using both arti cial and real observations

    Climate change impacts and adaptation in Europe, focusing on extremes and adaptation until the 2030s

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    This document reports the results of the analyses performed within the framework of the PESETA3 project regarding the Task 9 - Droughts. The main objective of this task is to provide robust scientific-based information to stakeholders and decision makers on the possible impacts of future climate scenarios on the occurrence of drought events. This report is focused on the analysis of the variations of soil moisture on the European continent, as well as of a soil moisture-based drought severity indicator (DSI), in order to evaluate the possible increase/decrease in future occurrence and severity of soil drought events and the related hazard and risk. Following the guideline of the project, five bias-corrected climatological datasets were used to force the LISFLOOD hydrological model that produces the daily soil moisture maps used in this analysis. These datasets were part of the EURO-CORDEX package and were used to characterize both the present reference period (1981-2010) and the future scenario at the date when a global 2 °C warming will occur according to the RCP8.5 scenario (different for each dataset and around the mid of the century). In the framework of this project, considering the specific purpose of the report, only the RCP8.5 scenario was selected in order to provide a clear indication on the possible future impacts of a strong climate change. The most relevant findings of the analysis depicted a scenario with differences that are statistically significant only on a limited fraction of the continental territories, with negative impacts limited to the Mediterranean and South-western Europe area for both soil moisture (reduction in water availability during both the dry and the wet season) and extreme drought events (increase in drought hazard). Particularly concerning is the increase of drought hazard over areas that are already drought prone and characterized by semi-arid climate, even if a limited impact on drought risk is expected due to the low present exposure and vulnerability of the same regions. Overall, it appears clear from this study that the EU goal to limit the global warming at 2 °C, as compared to the average temperature in pre-industrial times, will confine the variations in drought impacts to a minor fraction of the European continent in the near future, as shown by the obtained results.JRC.E.1-Disaster Risk Managemen

    Applying a probabilistic model of rainfall and snow days occurrence to daily series recorded in NW Italy.

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    Daily precipitation records exist spanning several decades. A valuable amount of climatic information exists in the time-series of interarrival times (IT), defined as the succession of times (number of days) elapsed from a rainy (or snowy) day to the one immediately preceding it.In a previous work, Agnese et al. (2014) have been successfully tested some probabilistic modelling of rain occurrence on Sicily rainfall data; particularly, the better fitting of IT’s observed frequencies was obtained by 3-parameter Lerch-series distribution. In this work thisdistribution is tested on 70 years of 20 precipitation time-series taken in the North-West Italy, both in the plain and in the mountains, up to the 2000 meters altitude. In such Mediterranean climatetwo markedly different behaviours were observed in the dry semester (April to September) and in the wet one (October to March). A better fit was obtained with that simple subdivision of the year, in comparison with the whole year modelling. However, the NW Italy climate is both more similar to the Central Europe one, and it is deeply influenced by the higher peaks of the Alps. Therefore the seasonality of daily precipitation data is much more complicated. Usually spring and fall are the seasons characterized by the higher precipitations, but the convective vs. frontal events also play a role in the IT distributions. In this work, different subdivisions were compared with the whole year fitting. The whole year Lerch distributions successfully fitted the data in a part of the time series, opening the way to interesting climate applications

    Soil moisture evaluation over the Argentine Pampas using models satellite estimations and in - situ measurements

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    Study region: The Pampas region is located in the central-east part of Argentina, and is one of the most productive agricultural regions of the world under rainfed conditions. Study focus: This study aims at examining how different Land Surface Models (LSMs) and satellite estimations reproduce daily surface and root zone soil moisture variability over 8 in-situ observation sites. The ability of the LSMs to detect dry and wet events is also evaluated. New hydrological insights for the region: The surface and root zone soil moisture of the LSMs and the surface soil moisture of the ESA CCI (European Space Agency Climate Change Initiative, hereafter ESA-SM) show in general a good performance against the in-situ measurements. In particular, the BHOA (Balance Hidrológico Operativo para el Agro) shows the best representation of the soil moisture dynamic range and variability, and the GLDAS (Global Land Data Assimilation System)-Noah, ERA-Interim TESSEL (Tiled ECMWF’s Scheme for Surface Exchanges over Land) and Global Drought Observatory (GDO)-LISFLOOD are able to adequately represent the soil moisture anomalies over the Pampas region. In addition to the LSM results, also the ESASM satellite estimated anomalies proved to be valuable. However, the LSMs and the ESA-SM have difficulties in reproducing the soil moisture frequency distributions. Based on this study, it is clear that accurate forcing data and soil parameters are critical to substantially improve the ability of LSMs to detect dry and wet events.Fil: Spennemann, P.C. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Servicio Meteorológico Nacional; Argentina Universidad Nacional de Tres de Febrero; ArgentinaFil: Fernández - Long, M.E. Universidad de Buenos Aires. Facultad de Agronomía; ArgentinaFil: Gattinoni, Natalia N. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Clima y Agua; ArgentinaFil: Cammalleri, C. European Commission, Joint Research Centre; ItaliaFil: Naumann, G. European Commission, Joint Research Centre; Itali

    Global warming and drought impacts in the EU

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    Droughts induce a complex web of impacts that span many sectors of the economy, as exemplified by extensive crop failure, reduced power supply, and shipping interruptions in the EU during 2018 and 2019. With global warming droughts will happen more frequent, last longer and become more intense in southern and western parts of Europe, while drought conditions will become less extreme in northern and north-eastern Europe. With 3°C global warming in 2100 drought losses could be 5 times higher compared to today, with the strongest increase in drought losses projected in the Mediterranean and Atlantic regions of Europe. When expressed with respect to the total size of the economy the effects are dampened relatively, because drought-sensitive sectors like agriculture are projected to become relatively less economically prevalent in future EU economies than they are nowadays. The consequences on ecosystems are typically not monetized and hence are not reflected in the loss estimates.JRC.E.1-Disaster Risk Managemen

    Annual Progress Report of the European and Global Drought Observatories

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    With this report, the reader finds an overview of the changes, upgrades and new features created in the European Drought Observatory (EDO) and the Global Drought Observatory (GDO) and made in 2019. The year proved relatively quiet concerning drought events in Europe; the subcontinent was only affected in the Baltics, although fires broke out vigorously in the Balkans, Spain and Russia. Thanks to the recent juvenile concern with regard to the heating up of the climate, drought events and forest fires drew more public-attention. Our reaction upon this concern in the Global Drought Observatory is the development of a new group of data, which we call Drought Mitigation. With more people genuinely concerned in the effect of our alternation of the properties of the lower atmosphere, we take up the task to provide guidelines for repair and adaptation. Higher temperatures imply that air depletes more vapour from vegetation and soil, leading to more intense droughts or floods. Consient management of our fresh water resources and massive tree planting are measures that can have significant impact on the effects of a Drought, Forest Fires or also Flood events. Therefore, we started with including the results of the often-cited research result regarding reforestation potential of the Crowther Lab as a layer in the Global Drought Observatory. We completed our work with enriching data describing dams with data regarding the location, name and quantitative characteristics of dams as an additional layer. We worked on the integration of the GRACE Dataset, which gives us an actualized satellite born, insight in the depletion of groundwater resources. We created a new index, alerting drought impacts on protected wetlands. Droughts events in these areas might affect rare species living in these protected wetlands, thus creating a link to the biodiversity crisis. The drought alerting mechanism we developed thus far were human centred. With this new index and with the Crowther Lab reforestation inventory we hope to correct this one species view of the past, learning to share our territory with all species, also during hard times of a drought disaster. With these additions, we hope that EDO and GDO will give you a better overview of the impacts of drought events, not only for our economy but also for our shared ecosystems and their services to us. Finally note that we engage in a project to export EDO and GDO knowledge and software to African regional partners. Thus enabling them to set up drought observatories in Africa just as if we did for South- and Central America. Such a collaboration works both ways, we understand better the impacts of Drought events in their region and we learn from their practical skills with regard to make things work in a challenging environment, whilst we can give them working drought observatory software, practical manners to, almost, fully automate the filling and updating of the systems combined with our specific expertise on droughts build up in the last 12 years.JRC.E.1-Disaster Risk Managemen

    Climate change impacts and adaptation in Europe

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    The JRC PESETA IV study shows that ecosystems, people and economies in the EU will face major impacts from climate change if we do not urgently mitigate greenhouse gas emissions or adapt to climate change. The burden of climate change shows a clear north-south divide, with southern regions in Europe much more impacted, through the effects of extreme heat, water scarcity, drought, forest fires and agriculture losses. Limiting global warming to well below 2°C would considerably reduce climate change impacts in Europe. Adaptation to climate change would further minimize unavoidable impacts in a cost-effective manner, with considerable co-benefits from nature-based solutions.JRC.C.6-Economics of Climate Change, Energy and Transpor

    Mapping and Assessment of Ecosystems and their Services: An EU ecosystem assessment

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    This report presents an ecosystem assessment covering the total land area of the EU as well as the EU marine regions. The assessment is carried out by Joint Research Centre, European Environment Agency, DG Environment, and the European Topic Centres on Biological Diversity and on Urban, Land and Soil Systems. This report constitutes a knowledge base which can support the evaluation of the 2020 biodiversity targets. It also provides a data foundation for future assessments and policy developments, in particular with respect to the ecosystem restoration agenda for the next decade (2020-2030). The report presents an analysis of the pressures and condition of terrestrial, freshwater and marine ecosystems using a single, comparable methodology based on European data on trends of pressures and condition relative to the policy baseline 2010. The following main conclusions are drawn: - Pressures on ecosystems exhibit different trends. - Land take, atmospheric emissions of air pollutants and critical loads of nitrogen are decreasing but the absolute values of all these pressures remain too high. - Impacts from climate change on ecosystems are increasing. - Invasive alien species of union concern are observed in all ecosystems, but their impact is particularly high in urban ecosystems and grasslands. - Pressures from overfishing activities and marine pollution are still high. - In the long term, air and freshwater quality is improving. - In forests and agroecosystems, which represent over 80% of the EU territory, there are improvements in structural condition indicators (biomass, deadwood, area under organic farming) relative to the baseline year 2010 but some key bio-indicators such as tree-crown defoliation continue to increase. This indicates that ecosystem condition is not improving. - Species-related indicators show no progress or further declines, particularly in agroecosystems. The analysis of trends in ecosystem services concluded that the current potential of ecosystems to deliver timber, protection against floods, crop pollination, and nature-based recreation is equal to or lower than the baseline value for 2010. At the same time, the demand for these services has significantly increased. A lowered potential in combination with a higher demand risks to further decrease the condition of ecosystems and their contribution to human well-being. Despite the wide coverage of environmental legislation in the EU, there are still large gaps in the legal protection of ecosystems. On land, 76% of the area of terrestrial ecosystems, mainly forests, agroecosystems and urban ecosystems, are excluded from a legal designation under the Bird and Habitat Directives. Freshwater and marine ecosystems are subject to specific protection measures under the Water Framework and Marine Strategy Framework Directives. The condition of ecosystems that are under legal designation is unfavourable. More efforts are needed to bend the curve of biodiversity loss and ecosystem degradation and to put ecosystems on a path to recovery. The progress that is made in certain areas such as pollution reduction, increasing air and water quality, increasing share of organic farming, the expansion of forests, and the efforts to maintain marine fish stocks at sustainable levels show that a persistent implementation of policies can be effective. These successes should encourage us to act now and to put forward an ambitious plan for the restoration of Europe’s ecosystems.JRC.D.3-Land Resource
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