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European forests are an important source for timber production, human welfare, income, protection and biodiversity. During the last two decades, Europe has experienced a number of droughts which have been exceptional within the last 500 years, both in terms of duration and intensity. These droughts seem to leave remarkable imprints on the mortality dynamics of European forests. However, systematic observations on tree decline, with emphasis on a single species, has been scarce so far so that our understanding of mortality dynamics and drought occurrence is still limited at a continental scale. Here, we make use of the ICP Forest crown defoliation dataset, permitting us to retrospectively monitor tree mortality for all major conifers, major broadleaves, as well as a pooled dataset of minor tree species in Europe. In total, we analysed more than three million observations gathered during the last 25 years and employed a high-resolution drought index which can assess soil moisture anomaly based on a hydrological water-balance and runoff model. We found overall and species-specific increasing trends in mortality rates, accompanied by decreasing soil moisture. A generalized linear mixed model identified a previous-year soil moisture anomaly as the most important driver of mortality patterns in conifers, but the response was not uniform across the numerous analysed plots. We conclude that mortality patterns in European forests are currently reaching a concerning upward trend which could be further accelerated by global change-type droughts in the near future.

Forests are currently experiencing an unprecedented period of progressively drier growing conditions around the globe, which is threatening many forest ecosystem functions. Trees as long-living organisms are able to withstand drought periods. Our understanding on critical drought severity resulting in substantial decline in net primary productivity and/or eventually tree mortality is underdeveloped. A wide range of remote sensing products and ground observations, including information on productivity, tree vitality, climate, and soil moisture with high temporal and spatial resolution are now available. Linking these data sources could improve our understanding of the complex relationship between forest growth and drought. We introduce here a conceptual framework using satellite remotely sensed net primary productivity (MOD17A3 and MODIS EURO), ground observations of tree mortality (ICP level I survey data), soil moisture anomaly (Copernicus European Drought Observatory), and spatially-downscaled daily climate data for entire Europe. This unique analysis will enable us to test the influence of biotic and abiotic covariates such as tree age, stand history, and drought legacy using historic droughts for model development. This conceptual framework, as evident from the preliminary results shown here, can help anticipating the effects of future droughts and optimize global climate models considering drought effects.

Studies have shown that the footprint of a single eddy covariance (EC) system may not yield representative measurements of the turbulent fluxes at the field scale for sparse vegetated surfaces, whereas scintillometry, due to its larger footprint, may be more suitable for this purpose. However, the latter approach strongly relies on the Monin-Obukov similarity theory (MOST) that strictly applies in the inertial sub-layer only. This work aims at experimentally confirm the reliability of displaced-beam laser scintillometers (DBLS) measurements over an olive orchard against two EC systems during summer and autumn months of 2007 through 2009. It was found that the DBLS underestimated both the momentum and sensible heat fluxes by 15 to 20% when established retrieval procedures were applied. A new method to determine the sensible heat flux from the DBLS based on the addition of a single-height wind speed measurement was tested, yielding estimates that compare well with the EC observations, with discrepancies in sensible heat fluxes of about 30 to 40 W m-2.

The concept of reference potranspiration is widely used to support water resource management in agriculture and for irrigation scheduling, especially under arid and semi-arid conditions. The Penman-Monteith standardized formulations, as suggested by ASCE and FAO-56 papers, are generally applied for accurate estimations of ETo, at hourly and daily scale. When detailed meteorological information are not available, several alternative and simplified equations, using a limited number of variables, have been proposed (Blaney-Criddle, HargreavesSamani, Turc, Makkinen and Pristley-Taylor). In this paper, scintillometer measurements collected for six month in 2005, on an experimental plot under “reference” conditions, were used to validate different ETo equations at hourly and daily scale. Experimental plot is located in a typical agricultural Mediterranean environment (Sicily, Italy), where olive groves is the dominant crop. As proved by other researches, the comparison confirmed the best agreement between estimated and measured fluxes corresponds to FAO-56 Penman-Monteith standardized equation, that was characterized by both the lowest average error and the minimum bias. However, the analysis also evidenced a quite good performance of Pristley-Taylor equation, that can be considered as a valid alternative to the more sophisticated PenmanMonteith method. The different ETo series, obtained by the considered simplified equations, were then used as input in the FAO-56 water balance model, in order to evaluate, for olive groves, the errors on estimated actual evapotranspiration ET. To this aim soil and crop model input parameters were settled by considering previous experimental researches already used to calibrate and validate the FAO-56 water balance model on olive groves, for the same study area. Also in this case, assuming as the true values of ET those obtained using the water balance coupled with Penman- Monteith ETo input values, the Priestley-Taylor equation, requiring a limited number of input meteorological data, was characterized by the best performance if compared to the other equations used to evaluate ETo. Under environments conditions similar to those considered therefore, according to the good performance associated to the Priestley-Tailor approach, FAO-56 model can allow realistic estimation of ET, even in absence of a full meteorological dataset.

L’uso razionale della risorsa idrica in agricoltura richiede, unitamente all’adozione di tecniche irrigue avanzate che assicurino la migliore efficienza degli interventi irrigui, l’individuazione dei tempi e dell’entità dei singoli interventi. Perché questi ultimi obiettivi siano raggiunti è necessario stimare con precisione i consumi di evapotraspirazione delle colture che, nell’ambiente mediterraneo, caratterizzato da un periodo vegetativo tipicamente non in fase con quello piovoso, si manifestano sotto condizioni di stress idrico. Nel presente lavoro è descritta un’applicazione a una piantagione di oliveto della tecnica scintillometrica, che permette una stima indiretta del flusso di calore latente attraverso l’equazione del bilancio energetico. Più in particolare, lo scintillometro è uno strumento ottico, che misura il flusso di calore sensibile dal sistema suolo-pianta sulla base degli effetti che tale flusso induce sull’indice di rifrazione della luce coerente emessa da un trasmettitore; misurando contemporaneamente la radiazione netta e il flusso di calore nel suolo, è possibile dedurre il flusso di evapotraspirazione come termine residuo dell’equazione che esprime il bilancio energetico di superficie. Sono in particolare presentati i risultati di un’indagine sperimentale effettuata nel corso della stagione irrigua 2007 nell’area di Castelvetrano, tipicamente vocata alla coltura dell’olivo. I dati di evapotraspirazione giornaliera ottenuti mediante la tecnica scintillometrica sono stati quindi confrontati con i corrispondenti valori stimati utilizzando il modello Agroidrologico SWAP, la cui applicazione ha richiesto una approfondita caratterizzazione biofisica dell’area di studio. I dati di evapotraspirazione giornaliera ottenuti mediante la tecnica scintillometrica sono stati confrontati con i corrispondenti valori stimati utilizzando sia il modello agroidrologico SWAP che la procedura semplificata proposta di recente dalla FAO che prevede l’adozione di un coefficiente colturale Kc,r che tiene conto delle eventuali condizioni di stress idrico.

Studies have shown that the footprint of a single eddy covariance (EC) system may not yield representative measurements of the turbulent fluxes at the field scale for sparse vegetated surfaces, whereas scintillometry, due to its larger footprint, may be more suitable for this purpose. However, the latter approach strongly relies on the Monin-Obukhov similarity theory (MOST) that strictly applies in the inertial sub-layer only. This work aims at experimentally confirm the reliability of displaced-beam laser scintillometer (DBLS) measurements over an olive orchard against two EC systems during summer and autumn months of 2007 through 2009. It was found that the DBLS underestimated both the momentum and sensible heat fluxes by 15 to 20% when established retrieval procedures were applied. A new method to determine the sensible heat flux from the DBLS based on the addition of a single-height wind speed measurement was tested, yielding estimates that compare well with the EC observations, with discrepancies in sensible heat fluxes of about 30 to 40 W m(-2).

Actual evapotranspiration from typical Mediterranean crops has been assessed in a Sicilian study area by using surface energy balance (SEB) and soil-water balance models. Both modelling approaches use remotely sensed data to estimate evapotranspiration fluxes in a spatially distributed way. The first approach exploits visible (VIS), near-infrared (NIR) and thermal (TIR) observations to solve the surface energy balance equation whereas the soil-water balance model uses only VIS-NIR data to detect the spatial variability of crop parameters. Considering that the study area is characterized by typical spatially sparse Mediterranean vegetation, i.e. olive, citrus and vineyards, alternating bare soil and canopy, we focused the attention on the main conceptual differences between one-source and two-sources energy balance models. Two different models have been tested: the widely used one-source SEBAL model, where soil and vegetation are considered as the sole source (mostly appropriate in the case of uniform vegetation coverage) and the two-sources TSEB model, where soil and vegetation components of the surface energy balance are treated separately. Actual evapotranspiration estimates by means of the two surface energy balance models have been compared vs. the outputs of the agro-hydrological SWAP model, which was applied in a spatially distributed way to simulate one-dimensional water flow in the soil-plant-atmosphere continuum. Remote sensing data in the VIS and NIR spectral ranges have been used to infer spatially distributed vegetation parameters needed to set up the upper boundary condition of SWAP. Actual evapotranspiration values obtained from the application of the soil water balance model SWAP have been considered as the reference to be used for energy balance models accuracy assessment. Airborne hyperspectral data acquired during a NERC (Natural Environment Research Council, UK) campaign in 2005 have been used. The results of this investigation seem to prove a slightly better agreement between SWAP and TSEB for some fields of the study area. Further investigations are programmed in order to confirm these indications.

Funding Information: This open-access publication was funded by the University of Freiburg. Funding Information: Financial support. The project is supported by the Wassernetzwerk Baden-Württemberg (Water Research Network of the State Baden-Württemberg), which is funded by the Ministerium für Wissenschaft, Forschung und Kunst Baden-Württemberg (Ministry of Science, Research and the Arts of the State Baden-Württemberg) (grant no. AZ. 7532.21/2.1.6) and Maa-ja vesitekniikan tuki ry foundation. Doris E. Wendt acknowledges her support as part of the NERC-funded Groundwater Drought Initiative (NE/R004994/1). Lucy J. Barker was supported by the Natural Environment Research Council (NE/R016429/1) as part of the UK-SCAPE programme delivering National Capability. The contributions of Mirek Trnka, Lenka Bartošová, and Jaak Jaagus have been supported by SustES – Adaptation strategies for sustainable ecosystem services and food security under adverse environmental conditions (CZ.02.1.01/0.0/0.0/16_019/0000797). Publisher Copyright: © 2022 Veit Blauhut et al. Drought events and their impacts vary spatially and temporally due to diverse pedo-climatic and hydrologic conditions, as well as variations in exposure and vulnerability, such as demographics and response actions. While hazard severity and frequency of past drought events have been studied in detail, little is known about the effect of drought management strategies on the actual impacts and how the hazard is perceived by relevant stakeholders. In a continental study, we characterised and assessed the impacts and the perceptions of two recent drought events (2018 and 2019) in Europe and examined the relationship between management strategies and drought perception, hazard, and impact. The study was based on a pan-European survey involving national representatives from 28 countries and relevant stakeholders responding to a standard questionnaire. The survey focused on collecting information on stakeholders' perceptions of drought, impacts on water resources and beyond, water availability, and current drought management strategies on national and regional scales. The survey results were compared with the actual drought hazard information registered by the European Drought Observatory (EDO) for 2018 and 2019. The results highlighted high diversity in drought perception across different countries and in values of the implemented drought management strategies to alleviate impacts by increasing national and sub-national awareness and resilience. The study identifies an urgent need to further reduce drought impacts by constructing and implementing a European macro-level drought governance approach, such as a directive, which would strengthen national drought management and mitigate damage to human and natural assets.

Il saggio analizza la fattispecie del giustificato motivo oggettivo di licenziamento e i connessi rimedi (art. 18 post riforma '"Fornero" e d.lgs. 23/2015), ed evidenzia la lettura 'liberista' operata dalla giurisprudenza. The essay analyses individual dismissals for economic grounds and related remedies (art. 18 Workers' Statute after "Fornerno" reform and legislative decree no. 23/2015), and it highlights the neoliberal reading made by labour courts.

Thermal infrared (TIR) remote sensing of land-surface temperature (LST) provides valuable information about the sub-surface moisture status required for estimating evapotranspiration (ET) and detecting the onset and severity of drought. While empirical indices measuring anomalies in LST and vegetation amount (e.g., as quantified by the Normalized Difference Vegetation Index; NDVI) have demonstrated utility in monitoring ET and drought conditions over large areas, they may provide ambiguous results when other factors (e.g., air temperature, advection) are affecting plant functioning. A more physically based interpretation of LST and NDVI and their relationship to sub-surface moisture conditions can be obtained with a surface energy balance model driven by TIR remote sensing. The Atmosphere-Land Exchange Inverse (ALEXI) model is a multi-sensor TIR approach to ET mapping, coupling a two-source (soil + canopy) land-surface model with an atmospheric boundary layer model in time-differencing mode to routinely and robustly map daily fluxes at continental scales and 5 to 10-km resolution using thermal band imagery and insolation estimates from geostationary satellites. A related algorithm (DisALEXI) spatially disaggregates ALEXI fluxes down to finer spatial scales using moderate resolution TIR imagery from polar orbiting satellites. An overview of this modeling approach is presented, along with strategies for fusing information from multiple satellite platforms and wavebands to map daily ET down to resolutions on the order of 10 m. The ALEXI/DisALEXI model has potential for global applications by integrating data from multiple geostationary meteorological satellite systems, such as the US Geostationary Operational Environmental Satellites, the European Meteosat satellites, the Chinese Fen-yung 2B series, and the Japanese Geostationary Meteorological Satellites. Work is underway to further evaluate multi-scale ALEXI implementations over the US, Europe, Africa and other continents with geostationary satellite coverage.

For open orchard and vineyard canopies containing significant fractions of exposed soil (>50%), typical of Mediterranean agricultural regions, the energy balance of the vegetation elements is strongly influenced by heat exchange with the bare soil/substrate. For these agricultural systems a "two-source" approach, where radiation and turbulent exchange between the soil and canopy elements are explicitly modelled, appears to be the only suitable methodology for reliably assessing energy fluxes. In strongly clumped canopies, the effective wind speed profile inside and below the canopy layer can highly influence the partitioning of energy fluxes between the soil and vegetation components. To assess the impact of in-canopy wind profile on model flux estimates, an analysis of three different formulations is presented, including algorithms from Goudriaan (1977), Massman (1987) and Lalic et al. (2003). The in-canopy wind profile formulations are applied to the thermal-based Two-Source Energy Balance (TSEB) model developed by Norman et al. (1995) and modified by Kustas and Norman (1999). High resolution airborne remote sensing images, collected over an agricultural area located in the western part of Sicily (Italy) comprised primarily of vineyards, olive and citrus orchards, are used to derive all the input parameters need to apply the TSEB. The images were acquired from June to October 2008 and include a relatively wide range of meteorological and soil moisture conditions. A preliminary sensitivity analysis of the three wind profile algorithms highlight the dependence of wind speed just above the soil/substrate to leaf area index and canopy height over the typical canopy properties range of these agricultural area. It is found that differences in wind just above surface among the models is most significant under sparse and medium fractional cover conditions (20–60%). The TSEB model heat flux estimates are compared with micrometeorological measurements from a small aperture scintillometer and an eddy covariance tower collected over an olive orchard characterized by moderate fractional vegetation cover (≈35%) and relatively tall crop height (≈3.5 m). TSEB fluxes for the 7 image acquisition dates generated using both the Massman and Goudriaan in-canopy wind profile formulations give close agreement with measured fluxes, while the Lalic et al. equations yield poor results. The Massman wind profile scheme slightly outperforms that of Goudriaan, but it requires an additional parameter describing the roughness of the underlying vegetative surface. This parameter is not directly obtainable using remote sensing, hence this study suggests that the Goudriaan formulation for landscape applications is most suitable when detailed site-specific information regarding canopy architecture is unavailable.

For open orchard and vineyard canopies containing significant fractions of exposed soil (>50%), typical of Mediterranean agricultural regions, the energy balance of the vegetation elements is strongly influenced by heat exchange with the bare soil/substrate. For these agricultural systems a "two-source" approach, where radiation and turbulent exchange between the soil and canopy elements are explicitly modelled, appears to be the only suitable methodology for reliably assessing energy fluxes. In strongly clumped canopies, the effective wind speed profile inside and below the canopy layer can strongly influence the partitioning of energy fluxes between the soil and vegetation components. To assess the impact of in-canopy wind profile on model flux estimates, an analysis of three different formulations is presented, including algorithms from Goudriaan (1977), Massman (1987) and Lalic et al. (2003). The in-canopy wind profile formulations are applied to the thermal-based two-source energy balance (TSEB) model developed by Norman et al. (1995) and modified by Kustas and Norman (1999). High resolution airborne remote sensing images, collected over an agricultural area located in the western part of Sicily (Italy) comprised primarily of vineyards, olive and citrus orchards, are used to derive all the input parameters needed to apply the TSEB. The images were acquired from June to October 2008 and include a relatively wide range of meteorological and soil moisture conditions. A preliminary sensitivity analysis of the three wind profile algorithms highlights the dependence of wind speed just above the soil/substrate to leaf area index and canopy height over the typical range of canopy properties encountered in these agricultural areas. It is found that differences among the models in wind just above the soil surface are most significant under sparse and medium fractional cover conditions (15–50%). The TSEB model heat flux estimates are compared with micro-meteorological measurements from a small aperture scintillometer and an eddy covariance tower collected over an olive orchard characterized by moderate fractional vegetation cover (≈35%) and relatively tall crop (≈3.5 m). TSEB fluxes for the 7 image acquisition dates generated using both the Massman and Goudriaan in-canopy wind profile formulations give close agreement with measured fluxes, while the Lalic et al. equations yield poor results. The Massman wind profile scheme slightly outperforms that of Goudriaan, but it requires an additional parameter accounting for the roughness sub-layer of the underlying vegetative surface. The analysis also suggests that within-canopy wind profile model discrepancies become important, in terms of impact on modelled sensible heat flux, only for sparse canopies with moderate vegetation coverage.

Climate change is anticipated to alter the demand and supply of water at the earth's surface. Since many societal impacts from a lack of water happen under drought conditions, it is important to understand how droughts may develop with climate change. This study shows how hydrological droughts will change across Europe with increasing global warming levels (GWLs of 1.5, 2, and 3 K above pre-industrial temperature). We employed a low-flow analysis based on river discharge simulations of the LISFLOOD (De Roo et al., 2000) spatially distributed physically based hydrological and water use model, which was forced with a large ensemble of regional climate model projections under high emissions (RCP8.5) and moderate mitigation (RCP4.5) Representative Concentration Pathways. Different traits of drought, including severity, duration, and frequency, were investigated using the threshold level method. The projected changes in these traits identify four main sub-regions in Europe that are characterized by somehow homogeneous and distinct behaviours with a clear south-west–north-east contrast. The Mediterranean and Boreal sub-regions (defined in Sect. 3.1.1) of Europe show strong but opposite changes at all three GWLs, with the former area mostly characterized by stronger droughts (with larger differences at 3 K), while the latter is expected to experience a reduction in all drought traits. In the Atlantic and Continental sub-regions, the changes are expected to be less marked and characterized by a larger uncertainty, especially at the 1.5 and 2 K GWLs. Combining the projections in drought hazard with population and agricultural information shows that with 3 K global warming an additional 11 million people and 4.5 ×106 ha of agricultural land are projected to be exposed to droughts every year, on average, with the most affected areas located in the Mediterranean and Atlantic regions of Europe.

While climate change will alter the distribution of water in time and space, quantifications of drought risk under global warming remain uncertain. Here, we show that in Europe, drought damages could strongly increase with global warming and cause a regional imbalance in future drought impacts. In the absence of climate action (4 °C in 2100 and no adaptation), annual drought losses in the European Union and United Kingdom combined are projected to rise to more than €65 billion per year compared with €9 billion per year currently, or two times larger when expressed relative to the size of the economy. Drought losses show the strongest rise in southern and western parts of Europe, where drought conditions at 4 °C could reduce regional agriculture economic output by 10%. With high warming, drought impacts will become a fraction of current impacts in northern and northeastern regions. Keeping global warming well below 2 °C would avoid most impacts in affected regions. Climate change impacts precipitation patterns, and thus the risk for drought. Damages from drought in Europe will increase with losses more than €65 billion per year in a scenario without climate mitigation; keeping warming below 2 °C avoids most impacts.

Il saggio analizza la risposta dell’ordinamento intersindacale all’emergenza epidemiologica da Covid-19 in materia di salute e sicurezza nei luoghi di lavoro attraverso una disamina del Protocollo del 24 aprile 2020, e delle prime applicazioni contrattualcollettive. Tecnicismi a parte, lo studio sottolinea come le misure pattuite dalle parti sociali specificano ed integrano gli obblighi inderogabili e generali di legge in materia di salute e sicurezza. Infine, il saggio si interroga sulla compatibilità tra meccanismi di contact tracing e privacy all'insegna di una prospettiva multi-livello. The essay focuses on the recent measures undertaken by social partners against Covid-19 in the field of health and safety in the working place, throughout an analisis of the Protocol of 24 April 2020, and the first developments contained in sectoral and company agreements. Despite the technicalities, the paper pinpoints that the measures agreed by social partners specify and complement the general and minimum rules set by legislation. Eventually, the current work deals with contact tracing mechanisms and their compatibility with personal data protection principles under a multi-level perspective.

Il capitolo esamina la disciplina della tutela dei lavoratori in caso di infortunio dovuto al coronavirus

Il saggio analizza in chiave critica le misure di sostegno al reddito predisposte dal Governo al fine di proteggere i lavoratori dalle ricadute economiche derivanti dalla sospensione del rapporto di lavoro a causa dell'emergenza epidemiologica

The outcomes of the 2015 Paris Agreement triggered a number of climate impact assessments, such as for floods and droughts, to focus on future time frames corresponding to the years of reaching specific levels of global warming. Yet, the links between the timing of the warming levels and the corresponding greenhouse gas concentration pathways to reach them remain poorly understood. To address this gap, we compared projected changes of annual mean, extreme high, and extreme low river discharges in Europe at 1.5 &deg, C and 2 &deg, C under Representative Concentration Pathways RCP8.5 and RCP4.5 from an ensemble of regional climate model (RCM) simulations. The statistical significance of the difference between the two scenarios for both warming levels was then evaluated. The results show that in the majority of Europe (&gt, 95% of the surface area for the annual mean discharge, &gt, 98% for high and low extremes), the changes projected in the two pathways were statistically indistinguishable. These results suggest that in studies of changes at global warming levels, the projections of the two pathways can be merged into a single ensemble without major loss of information. With regard to the uncertainty of the unified ensemble, the findings show that the projected changes of annual mean, extreme high, and extreme low river discharge were statistically significant in large portions of Europe.

Among the indirect estimation approaches of soil water content in the upper layer of the soil, the &ldquo, triangle method&rdquo, is one of the most common that relies on the simple relationship between the optical and thermal features sensed via Earth Observation. These features are controlled by water content at the surface and within the root zone but also by meteorological forcing including air temperature and humidity, as well as solar radiation. Night- and day-time MODIS composites of land-surface temperature (LST) allowed applying a version of the triangle method that takes into account the temporal admittance of the soil. In this study, it has been applied to a long time-series of pair images to analyze the seasonal influence of the meteorological forcing on a triangle method index (or temperature&ndash, vegetation index, TVX), as well as to discuss extra challenges of the diachronic approach including seasonality effects and the variability of environmental forcing. The Imera Meridionale basin (Sicily, Italy) has been chosen to analyze the method over a time-series of 12 years. The analysis reveals that, under these specific environmental and climatic conditions (strong seasonality and rainfall out of phase with vegetation growth), Normalized Difference Vegetation Index (NDVI) and LST pairs move circularly in time within the optical vs. thermal feature space. Concordantly, the boundaries of the triangle move during the seasons. Results showed a strong correlation between TVX and rainfall normalized amplitudes of the power spectra (r2 ~0.8) over the range of frequencies of the main harmonics.

The essay makes a comment on the articles 54, 55 and 56 of the Act of the legislative provisions on the protection and support of maternity and paternity

The statistical inference of the alternation of wet and dry periods in daily rainfall records can be achieved through the modelling of inter-arrival time-series, IT, defined as the succession of times elapsed from a rainy day and the one immediately preceding it. In this paper, under the hypothesis that ITs are independent and identically distributed random variables, a modelling framework based on a generalisation of the commonly adopted Bernoulli process is introduced. Within this framework, the capability of three discrete distributions, belonging to the Hurwitz–Lerch-Zeta family, to reproduce the main statistical features of IT time-series was tested. These distributions namely Lerch-series (Lerch), polylogarithmic- series (Polylog) and logarithmic-series (Log) were selected thanks to their capability to describe some peculiar properties usually observed in IT series derived from daily rainfall records: very high standard deviation and skewness, relatively high frequency associated to the unitary IT, monotonically decreasing frequencies with a slow decay. Both Polylog and Log distributions are special cases of the 3-parameter Lerch distribution with a decreasing number of free parameters (2- and 1-parameter, respectively). The analysis, performed on 55 raingauges located in Sicily (Italy) under a typical Mediterranean climate, suggests that a reliable statistical representation of IT can be attained with the 3-parameter Lerch distribution. Despite the marked seasonality of rainfall in the study area, a simple subdivision of the year into two 6-month periods, roughly corresponding to the dry ‘‘semester’’ (D-sem) and the wet ‘‘semester’’ (W-sem), allows a satisfactory reproduction of IT, as well as of wet spells (WS) and dry spells (DS), separately. It was also noticed that the 2-parameter Polylog distribution could be successfully used to reconstruct the DS frequency distribution only. This result suggests that the additional parameter of the Lerch distribution is required by the inclusion of WS into the analysis. Finally, considering that Polylog outperforms the commonly adopted Log, a noteworthy step forward in DS modelling can be achieved by using Polylog distribution rather than Log one.

A remote sensing-based approach to estimate actual evapotranspiration (ET) was tested in an area covered by olive trees and characterized by Mediterranean climate. The methodology is a modified version of the standard FAO-56 dual crop coefficient procedure, in which the crop potential transpiration, T p, is obtained by directly applying the Penman-Monteith (PM) equation with actual canopy characteristics (i.e., leaf area index, albedo and canopy height) derived from optical remote sensing data. Due to the minimum requirement of in-situ ancillary inputs, the methodology is suitable also for applications on large areas where the use of tabled crop coefficient values become problematic, due to the need of corrections for specific crop parameters, i.e., percentage of ground cover, crop height, phenological cycles, etc. The methodology was applied using seven airborne remote sensing images acquired during spring-autumn 2008. The estimates based on PM approach always outperforms the ones obtained using simple crop coefficient constant values. Additionally, the comparison of simulated daily evapotranspiration and transpiration with the values observed by eddy correlation and sap flow techniques, respectively, shows a substantial agreement during both dry and wet days with an accuracy in the order of 0.5 and 0.3 mm d−1, respectively. The obtained results suggest the capability of the proposed approach to correctly partition evaporation and transpiration components during both the irrigation season and rainy period also under conditions of significant reduction of actual ET from the potential one.

Correct estimation of crop actual transpiration plays a key-role in precision irrigation scheduling, since crop growth and yield are associated to the water passing through the crop. Objective of the work was to assess how the combined use of micro-meteorological techniques (eddy covariance, EC) and physiological measurements (sap flow, SF) allows a better comprehension of the processes involving in the Soil–Plant–Atmosphere continuum. To this aim, an experimental dataset of actual evapotranspiration, plant transpiration, and soil water content measurements was collected in an olive orchard during the midseason phenological period of 2009 and 2010. It was demonstrated that the joint use of EC and SF techniques is effective to evaluate the components of actual evapotranspiration in an olive orchard characterized by sparse vegetation and a significant fraction of exposed bare soil. The availability of simultaneous soil water content measurements allowed to estimate the crop coefficients and to assess a simple crop water stress index, depending on actual transpiration that can be evaluated even in the absence of direct measurements of actual transpiration. The crop coefficients experimentally determined resulted very similar to those previously evaluated; in particular, in the absence of water stress, a seasonal average value of about 0.65 was obtained for the “single” crop coefficient, whereas values of a 0.34 and 0.41 were observed under limited water availability in the root zone. The comparison between the values of crop water stress index evaluated during the investigated periods evidenced systematically lower values (less crop water stress) in the first year compared to the second, according to the general trend of soil waters content in the root zone. Further researches are however necessary to extent the experimental dataset to periods characterized by values of soil evaporation higher than those observed, in order to verify the crop coefficients even under different conditions than those investigated.

Equations based on surface renewal (SR) analysis to estimate the sensible heat flux (H) require as input the mean ramp amplitude and period observed in the ramp‐like pattern of the air temperature measured at high frequency. A SR‐based method to estimate sensible heat flux (HSR‐LST) requiring only low‐frequency measurements of the air temperature, horizontal mean wind speed, and land‐surface temperature as input was derived and tested under unstable conditions over a heterogeneous canopy (olive grove). HSR‐LST assumes that the mean ramp amplitude can be inferred from the difference between land‐surface temperature and mean air temperature through a linear relationship and that the ramp frequency is related to a wind shear scale characteristic of the canopy flow. The land‐surface temperature was retrieved by integrating in situ sensing measures of thermal infrared energy emitted by the surface. The performance of HSR‐LST was analyzed against flux tower measurements collected at two heights (close to and well above the canopy top). Crucial parameters involved in HSR‐LST, which define the above mentioned linear relationship, were explained using the canopy height and the land surface temperature observed at sunrise and sunset. Although the olive grove can behave as either an isothermal or anisothermal surface, HSR‐LST performed close to H measured using the eddy covariance and the Bowen ratio energy balance methods. Root mean square differences between HSR‐LST and measured H were of about 55 W m−2. Thus, by using multitemporal thermal acquisitions, HSR‐LST appears to bypass inconsistency between land surface temperature and the mean aerodynamic temperature. The one‐source bulk transfer formulation for estimating H performed reliable after calibration against the eddy covariance method. After calibration, the latter performed similar to the proposed SR‐LST method. This research was funded by project CGL2012‐37416‐C04‐01 and CGL2015‐65627‐C3‐1‐R (Ministerio de Ciencia y Innovación of Spain), CEI Iberus, 2014 (Proyecto financiado por el Ministerio de Educación en el marco del Programa Campus de Excelencia Internacional of Spain), and Ayuda para estancias en centros extranjeros (Ministerio de Educación, Cultura y Deporte of Spain).

According to the opinion accepted by most, labour law was born in the late nineteenth century in connection with the production processes delivered by the Industrial Revolution. Its genesis follows the paradigm for which is the main feature of this new production model to generate both socioeconomic and legal subordination. So, keeping this basic assumption, a research that wanted to investigate the origins of the employment, back-links from this period, it seems to stand outside of the legal framework that constitute generally its reference system. For the same reason, also the new post-industrial work organisation in the era of globalisation, although for different reasons and yet paradoxical, it tends to stand outside the natural riverbed of labor law and it tends to breaking free from it. This is the reason why there is the current tendency to talk about the labor market law, jobs law, job protections, rather than labour law and employment law. You can not escape that in every age, however, the concern of the law has been, and it always is, to assign the protection to who, by himself, that protection can not give it to himself. Well, this situation is an essential common need of the labour law both pre-industrial and industrial and post-industrial. Thus, the basic concerns of labour law in the era of globalisation are not different from those of previous eras. Let's change the superstructure of utilisation / exploitation of the labor of others - and correspondingly the legal structures that govern them - but it do not change the structures on which those forms are inserted; - in fact, at the root of it all there is the person, in one of its many most qualifying natural phenomena: that of work. Now, the Bible (both the Hebrew and Christian, in its different denominations) is - of course - a common humus to the whole so called the West and - in part - even to the Islam. As you know, the inextricable intertwining of theological requirements with social requirements, that are typical of theocratic societies, on the one side whether it does not make it easy to distinguish the one from the other (even supposing that such hermeneutic approach it can be useful and accessible); on the other side it might help to identify protection structures that, as referring to man in his relationship with creation - ( in the secular sense for non-believers ) and the creator - could likely to be erected to universal rules, without space or time, rules good to delineate the outer limits of regulation of employment at any time and any where. The purpose of this research is to catalogue the biblical texts - notably in a first phase those which are in the first (or old) testament of the Christian Bible - which contain both prescriptive structures and pathways, designed to protect the position of social weakness and minority of the worker, understood in its broadest sense and in its various and diverse facets: of worker, of salaried, of servant, even of slave, and so on. The starting point and most immediate objective of this work is therefore to find the biblical sources - and to get ready one first critical apparatus - which they refer to, directly or indirectly, to work in broad sense, that is a personal relationship in which one of the two subjects of it, is in a position of weakness, comparable to that which the Bible considers typical for orphans , widows, the poor and in some respects for foreigners: a one word the Weaks.

Reference evapotranspiration (ET 0 ) is widely used for irrigation scheduling, to promote an efficient use of water resources for a sustainable agro-ecosystem productivity, as well as to manage water quality and to face other environmental concerns. As suggested by ASCE-EWRI and FAO, standard Penman–Monteith methods are generally applied for an accurate estimation of ET 0 from hourly to daily scale. In absence of detailed meteorological information several simplified equations, using a limited number of variables, have been proposed as alternative. In this paper, the performance of different reference evapotranspiration methods, at hourly (Penman–Monteith, Pristley–Taylor, Makkink and Turc) and daily scale (Penman–Monteith, Blaney and Criddle, Hargreaves, Pristley–Taylor, Makkink and Turc), was evaluated against scintillometer measurements collected during six month in 2005 in an experimental plot maintained under “reference” conditions (alfalfa crop). The daily values of ET 0 obtained with the examined methodologies were then used as input in the FAO-56 agro-hydrological model, in order to evaluate, for an olive grove in a Mediterranean environment, the impact on simulated actual evapotranspiration. The experiment was carried out in South-West Sicily, in an area where olive groves are the major crop. The comparison between estimated and measured fluxes confirmed that FAO-56 Penman–Monteith (PM) standardized equation is characterized by the lowest mean bias error (−0.15 mm d −1 and 0.06 mm d −1 using daily or hourly data, respectively). Additionally, the analysis also highlighted that the Pristley–Taylor equation can be considered a valid alternative for an accurate estimation of ET 0 (mean bias error of 0.35 mm d −1 and 0.43 mm d −1 using daily or hourly data, respectively). The application of the FAO-56 water balance model on the investigated olive grove evidenced that the best estimations of actual evapotranspiration are obtained when the Pristley–Taylor ET 0 data are used as input, confirming that this approach can be considered a valid alternative to the standard Penman–Monteith.

In this work a set of time-series of inter-arrival times of rainfall events, at daily scale, was analysed, with the aim to verify the issue of increasing duration of dry periods. The set consists of 12 time-series recorded at rain gauges in 1926–2005, six of them belong to an Italian Sub-Alpine area (Piedmont) and six to a Mediterranean one (Sicily). In order to overcome the problem related to limited sample size for high values of inter-arrival times, the discrete probability polylog-series distribution was used to fit the empirical data from partial (20 yr) time-series. Moreover, a simple qualitative trend analysis was applied to some high quantiles of inter-arrival times as well as to the average extent of rain clusters. The preliminary analysis seems to confirm the issue of increasing duration of dry periods for both environments, which is limited to the ''cold'' season.

Summary An operational use of the actual evapotranspiration assessed by remote sensing approaches requires the integration of instantaneous fluxes to daily values. This is commonly achieved under the hypotheses of daytime self-preservation of evaporative fraction and negligible daily ground heat flux. The aim of this study is to evaluate the effect of these assumptions on estimate daily evapotranspiration over a full phenological cycle, including phases characterized by significant changes both in net radiation and vegetation cover. To assess the reliability of these hypotheses, the observations made by a flux tower, installed within a homogeneous field of cereal located in the valley part of the Imera Meridionale basin, were analyzed. Additionally, the widely-known SEBAL (Surface Energy Balance Algorithm for Land) model was applied on the same study area by means of four MODIS (MODerate-resolution Imaging Spectroradiometer) images selected across a three-rainfall events period in March–April 2007 with the aim to analyze the consistency of its estimates in an operational study case under different conditions of water availability. The analysis of in situ data highlights errors on 24-h evapotranspiration characterized by an average value of 20% due to daily soil heat flux neglecting; whereas, the hypothesis of evaporative fraction self-preservation causes an average error equal to −16%. Moreover, the analysis of the observations suggests that a compensation effect of the errors related to each hypothesis occurs in most cases (56%), and this makes suitable the approach for practical daily integration purposes. The application of the SEBAL model at basin scale shows a good capability to detect the increase of the actual 24-h evapotranspiration under the tested hypotheses, also in the case of instantaneous evaporative fraction and daily net radiation not derived form in situ observations.

Summary A coupled energy/hydrologic model was applied to simulate the exchange of energy and water in the soil–plant-atmosphere system (SPA). The model, which uses a “two-source” approach to estimate the energy fluxes, and the “force-restore” approach to represent the water balance, was validated by means of evapotranspiration measurements collected via scintillometry and soil moisture measurements collected via time domain reflectometry (TDR) in a Sicilian olive grove. The comparison between measured and estimated fluxes values at an hourly scale showed good agreement. Additional comparisons on a daily timescale confirmed the model’s applicability for quantifying crop water requirements. Also in terms of daily evapotranspiration and soil water content values, the obtained results confirmed the model’s applicability for those practical applications aiming to quantify the crop water requirement. Moreover, further studies should be conducted to test the feasibility of using this model for long term simulations over a broad range of conditions.

The paper critically addresses the origins of flexicurity and argues that it lacks an archetypical definition, especially in the formulation of the EU Commission. Hence, the paper, basing on a multidisciplinary literature, considers flexicurity as any balance between flexibility and security and, therefore, proposes ordering any set of contracts, providing the same balance and with the same regulatory framework, in “communities”. It is assumed, therefore, that communities can differ either in terms of a “protective” trade-off, where the differential is not a surrogate measure of security, or in terms of an economic trade-off, where it is met by the provision of social insurance or security. One of these sets is called community 0 and it corresponds to undeclared work, not only illegal, but also completely devoid of security and fully flexible. After identifying from ILO, EU and constitutional sources the foundation of the “incompressibility” of rights which guarantee decent work, the paper likens decent work to a public good of general interest, in the same way as laws generally recognize the natural environment. On the basis of this comparative axiom, the paper proposes considering the dispersion of security produced by undeclared work as “un-decent” work and, therefore, as a form of “pollution”. Because an environment can be little or very polluted, the paper proposes considering as social pollution any form, even legal, of security leakage - such as that induced by the precarious and atypical jobs. Any form of employment is, therefore, considered in an nth community and every community is ordered from the least secure to the most secure, using as tertium comparationis standard employment, which is itself a point of balance between flexibility and security, and it is therefore a community of flexicurity. In this way, each community expresses a degree of social participation in environmental pollution: from the maximum produced by undeclared work to the minimum produced by labour standard. The adopted economic approach allows defining this pollution as a negative externality and, therefore, refer to its contrast in terms of internalization. Among the techniques of internalization, the preferred one is the Pigovian tax, because it can overcome the difficulties associated with the identification of taxable income in the undeclared work and in the informal sector. It has been observed, in fact, that the insurance mechanism creates a regressive effect on the competitiveness of labour standards, making it less competitive in favour of precarious and atypical work and, thus, triggering a vicious cycle that increases social pollution. In this way, it is believed that on one hand you lose your interest in hiding most of the black job. On the other hand, a mechanism would be enforced that forces polluters to contribute to the financing of the security needed to address the pollution created. Because of the adopted ordering of communities, this positive effect would also impact on precarious forms of employment and atypical work in proportion to the security dispersed

Two regionalized models for the distributed estimation of daily reference evapotranspiration, the temperature-based Hargreaves (HE) and the radiation-based Makkink (MK) equations, are applied in Southern Italy during the years 2007 and 2008. Spatially distributed meteorological inputs, such as air temperature and incoming solar radiation, were derived from geostatistical interpolation of ground data and from the Land Surface Analysis Satellite Application Facility (LSA-SAF) surface radiation product, respectively. Comparison of the latter with 83,394 daily measurements provided by 128 weather stations shows a not negligible seasonal error in daily solar radiation that is corrected by means of a periodic equation. A preliminary local calibration of the MK coefficient highlights its strong dependency on the interactions between moist winds from the Atlantic Ocean and orographic obstructions, leading to two western and eastern subzones. Hence, a regionalization of the MK-adjusted coefficient was performed following a procedure similar to the one already used by the authors in a previous work for the HE coefficient. Application of both regionalized models and their comparison with Penman-Monteith estimates derived from the same stations leads to average whole-year absolute errors of approximately 0.5 mm d-1, further showing the great potential of the MK method in terms of informative content and less dependence on the site density of a ground-based monitoring network. Overall, discussing pros and cons of both regionalized models, it is shown that their integrated use in southern Italy is possible and advisable.

According to the opinion accepted by most, labour law was born in the late nineteenth century in connection with the production processes delivered by the Industrial Revolution. Its genesis follows the paradigm for which is the main feature of this new production model to generate both socioeconomic and legal subordination. So, keeping this basic assumption, a research that wanted to investigate the origins of the employment, back-links from this period, it seems to stand outside of the legal framework that constitute generally its reference system. For the same reason, also the new post-industrial work organisation in the era of globalisation, although for different reasons and yet paradoxical, it tends to stand outside the natural riverbed of labor law and it tends to breaking free from it. This is the reason why there is the current tendency to talk about the labor market law, jobs law, job protections, rather than labour law and employment law. You can not escape that in every age, however, the concern of the law has been, and it always is, to assign the protection to who, by himself, that protection can not give it to himself. Well, this situation is an essential common need of the labour law both pre-industrial and industrial and post-industrial. Thus, the basic concerns of labour law in the era of globalisation are not different from those of previous eras. Let's change the superstructure of utilisation / exploitation of the labor of others - and correspondingly the legal structures that govern them - but it do not change the structures on which those forms are inserted; - in fact, at the root of it all there is the person, in one of its many most qualifying natural phenomena: that of work. Now, the Bible (both the Hebrew and Christian, in its different denominations) is - of course - a common humus to the whole so called the West and - in part - even to the Islam. As you know, the inextricable intertwining of theological requirements with social requirements, that are typical of theocratic societies, on the one side whether it does not make it easy to distinguish the one from the other (even supposing that such hermeneutic approach it can be useful and accessible); on the other side it might help to identify protection structures that, as referring to man in his relationship with creation - ( in the secular sense for non-believers ) and the creator - could likely to be erected to universal rules, without space or time, rules good to delineate the outer limits of regulation of employment at any time and any where. The purpose of this research is to catalogue the biblical texts - notably in a first phase those which are in the first (or old) testament of the Christian Bible - which contain both prescriptive structures and pathways, designed to protect the position of social weakness and minority of the worker, understood in its broadest sense and in its various and diverse facets: of worker, of salaried, of servant, even of slave, and so on. The starting point and most immediate objective of this work is therefore to find the biblical sources - and to get ready one first critical apparatus - which they refer to, directly or indirectly, to work in broad sense, that is a personal relationship in which one of the two subjects of it, is in a position of weakness, comparable to that which the Bible considers typical for orphans , widows, the poor and in some respects for foreigners: a one word the Weaks.