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The aim of the study is to evaluate the association between summer temperatures and emergency department visits (EDVs) in Bologna (Italy) and assess whether this association varies across areas with different socioeconomic and microclimatic characteristics. We included all EDVs within Bologna residences during the summers of 2010–2019. Each subject is attributed a deprivation and a microclimatic discomfort index according to the residence. A time-stratified case-crossover design was conducted to estimate the risk of EDV associated with temperature and the effect modification of deprivation and microclimatic characteristics. In addition, a spatial analysis of data aggregated at the census block level was conducted by applying a Poisson and a geographically weighted Poisson regression model. For each unit increase in temperature above 26 °C, the risk of EDV increases by 0.4% (95%CI: 0.05–0.8). The temperature–EDV relationship is not modified by the microclimatic discomfort index but rather by the deprivation index. The spatial analysis shows that the EDV rate increases with deprivation homogeneously, while it diminishes with increases in median income and microclimatic discomfort, with differences across areas. In conclusion, in Bologna, the EDV risk associated with high temperatures is not very relevant overall, but it tends to increase in areas with a low socioeconomic level.

In 2019, the World Meteorological Organization published its “Guidance on Integrated Urban Hydrometeorological, Climate and Environment Services (Volume I: Concept and Methodology)” to assist WMO Members in developing and implementing the urban services that address the needs of city stakeholders in their countries. The guidance has relevant implications for not only protecting infrastructures from the impacts of climate change in the urban environment, but its proper declination strongly supports health-related policies to protect the population from direct and indirect impacts. Utilizing some principles of the guidance, the urbanized area of Bologna (Italy) was analyzed in order to furnish the municipality with tools coherent with the best practices actually emerging from the international bibliography to protect the citizens’ health of this city. Specifically, the analysis concentrated on the public spaces and the potential vulnerabilities of the fragile population to high-temperature regimes in the city. Utilizing the guidance as a methodological framework, the authors developed a methodology to define the microclimate vulnerabilities of the city and specific cards to assist the policymakers in city regeneration. Because the medieval structure of the city does not allow the application of a wide set of nature-based solutions, our main attention was placed on the possibility of furnishing the city with a great number of pocket parks obtainable from spaces actually dedicated to parking lots, thus introducing new green infrastructures in a highly deprived area in order to assure safety spaces for the fragile population.

While a substantial reduction of GHG (greenhouse gases) is urged, large-scale mitigation implies a detailed and holistic knowledge on the role of specific cropping systems, including the effect of management choices and local factors on the final balance between emissions and removals, this last typical of cropping systems. Here, a conventionally managed irrigated kiwifruit orchard has been studied to assess its greenhouse gases emissions and removals to determine its potential action as a C sink or, alternately, as a C source. The paper integrates two independent approaches. Biological CO2 fluxes have been monitored during 2012 using the micrometeorological Eddy covariance technique, while life cycle assessment quantified emissions derived from the energy and material used. In a climatic-standard year, total GHG emitted as consequence of the management were 4.25 t CO2-eq−1 ha−1 yr−1 while the net uptake measured during the active vegetation phase was as high as 4.9 t CO2 ha−1 yr−1. This led to a positive contribution of the crop to CO2 absorption, with a 1.15 efficiency ratio (sink-source factor defined as t CO2 stored/t CO2 emitted). The mitigating activity, however, completely reversed under extremely unfavorable climatic conditions, such as those recorded in 2003, when the efficiency ratio became 0.91, demonstrating that the occurrence of hotter and drier conditions are able to compromise the capability of Actinidia to offset the GHG emissions, also under appropriate irrigation.

A microclimate classification of the entire Bologna Municipality has been carried out in order to give a tool to the local administration in the drafting of the General Urbanistic Plan (PUG). The city was classified considering the variation of air temperature as a function of the surface characteristics, the vegetation fraction, the building density and the H/W ratio (height to width). Starting from the microclimate analysis carried out with fluid-dynamic modeling (Envi-met) for some areas of the city of urban interest, the air temperature variation was correlated to the physiological equivalent temperature (PET) in order to make a classification of physiological well-being for the resident population. An urban map of a normalized microclimate well-being index (BMN) has been obtained to give support when private, and public actors want to regenerate part of the city, taking into account the climate-centered approach for the development of a sustainability city.

The immediate threat climate change poses to our common future requires that we fully reconsider the ways in which humankind interacts with the environment. Cities and their development should be considered one of the most relevant issues considering that within the next few decades most of Earth's population will live inside city boundaries. The recent IPCC Special Report focused on the politics and mitigation strategies by which warming could be kept to within 1.5 °C. The most important chapter considered the actions, enforced by the Covenant of Majors, seeking to secure both population and production in the event that mitigation policies fail to be applied. The word that summarizes this approach is 'resilience'--the capability of a system to recover from strain. To build more resilient cities, knowledge must be shared by numerous intersecting disciplines and policy makers via networks such as C40. It is vital to advance our knowledge of the following topics: urban climate, the interaction between climate and meteorology in the urban structure, the possibility to apply climate services (recently, the WMO urban guide) to create auto-regenerative solutions in the city structure, and the capability to transform projects from the paper to the city itself. This Special Issue aims to investigate the state of the art connections between the various disciplines involved in urban transformation and to understand if a common language already exists.

Various environmental factors influence the outbreak and spread of epidemic or even pandemic events which, in turn, may cause feedbacks on the environment. The novel coronavirus disease (COVID-19) was declared a pandemic on 13 March 2020 and its rapid onset, spatial extent and complex consequences make it a once-in-a-century global disaster. Most countries responded by social distancing measures and severely diminished economic and other activities. Consequently, by the end of April 2020, the COVID-19 pandemic has led to numerous environmental impacts, both positive such as enhanced air and water quality in urban areas, and negative, such as shoreline pollution due to the disposal of sanitary consumables. This study presents an early overview of the observed and potential impacts of the COVID-19 on the environment. We argue that the effects of COVID-19 are determined mainly by anthropogenic factors which are becoming obvious as human activity diminishes across the planet, and the impacts on cities and public health will be continued in the coming years.

The human fingerprint called urbanization is a widespread phenomenon that has assumed increasing importance over the years, leading to the fact that more than half of the world's population actually lives in cities. The explosive and sudden growth of the urban settlements increased the vulnerability of their governing systems in terms of managing capacity as well as ability to defend citizens from environmental risks. The issue of climate change strongly enhances this vulnerability and imposes to fully reconsider the way we planned the urban development that characterize the city itself. To govern this problem policy actions, based on a strong scientific evidence, is necessary to address adaptation and mitigation strategies for the urban environment. In this frame the word resilience, defined as the capacity of a system to overpass a critical situation, is utilized in the regeneration processes and has to be considered an integral part of the processes of construction of the city itself.

relazioni tra i goal di sviluppo sostenibile e nuova progettazione urbana

Si analiazzano i cambiamenti climatici ed i loro effetti sulle citta'

All-wave net surface radiation is greatly needed in various scientific research and applications. Satellite data have been used to estimate incident shortwave radiation, but hardly to estimate all-wave net radiation due to the inference of clouds on longwave radiation. A practical solution is to estimate all-wave net radiation empirically from shortwave radiation and other ancillary information. Since existing models were developed using a limited number of ground observations, a comprehensive evaluation of these models using a global network of representative measurements is urgently required. In this study, we developed a new day-time net radiation estimation model and evaluated it against seven commonly used existing models using radiation measurements obtained from 326 sites around the world from 1991 to 2010. MERRA re-analysis products from which the meteorological data were derived and remotely sensed products during the same period were also used. Model evaluations were performed in both global mode (all data were used to fit the models) and conditional mode (the data were divided into four subsets based on the surface albedo and vegetation index, and the models were fitted separately). Besides, the factors (i.e., albedo, air temperature, and NDVI) that may impact the estimation of all-wave net radiation were also extensively explored. Based on these evaluations, the fitting RMSE of the new developed model was approximately 40.0 Wm −2 in the global mode and varied between 18.2 and 54.0 Wm −2 in the conditional mode. We found that it is better to use net shortwave radiation (including surface albedo) than the incident shortwave radiation nearly in all models. Overall, the new model performed better than other existing linear models.

Urban transformation and expansion in Mexico City continuously affect its urban morphology, and therefore the modes of wind circulation inside it and their occurrence probabilities. Knowledge on these topics is an important issue for urban planning and for other urban studies, such as air quality assessment. In this paper, using a lattice wind model at a meso-β scale, we develop a simple description and characterization of Mexico City local wind events that occurred during the period 2001–2006, including an estimation of the occurrence probabilities. This region was modeled as a 2D lattice domain of identical cells, and wind conditions in each cell were described by four wind attributes: the horizontal velocity components, divergence, and vorticity. Models of one and four cells were applied to wind data furnished by the meteorological network of the city. Results include the following: Early morning: low intensity winds (75%) from N, NW, W and SW (75%), convergent (93%), with a slight predominance of cyclonic vorticity (54%). Morning and early afternoon: winds from N, NE and E (72%) with speeds from 0.5 to 3.5 m/s, slight prevailing of convergent winds (51%), and slight predominance of cyclonic vorticity (57%). Late afternoon and night: winds blowing from N, NW, and S (63%) with speeds from 1.5 to 3.5 m/s (66%), convergent (90%), and cyclonic (72%).

Rapid and unplanned urban growth is responsible for the continuous conversion of green or generally natural spaces into artificial surfaces. The high degree of imperviousness modifies the urban microclimate and no studies have quantified its influence on the surface temperature (ST) nearby residential building. This topic represents the aim of this study carried out during summer in different urban zones (densely urbanized or park/rural areas) of Parma (Northern Italy). Daytime and nighttime ASTER images, the local urban cartography and the Italian imperviousness databases were used. A reproducible/replicable framework was implemented named Building Thermal Functional Area (BTFA) useful to lead building-proxy thermal analyses by using remote sensing data. For each residential building (n = 8898), the BTFA was assessed and the correspondent ASTER-LST value (ST_BTFA) and the imperviousness density were calculated. Both daytime and nighttime ST_BTFA significantly (p < 0.001) increased when high levels of imperviousness density surrounded the residential buildings. These relationships were mostly consistent during daytime and in densely urbanized areas. ST_BTFA differences between urban and park/rural areas were higher during nighttime (above 1 degrees C) than daytime (about 0.5 degrees C). These results could help to identify urban thermal Hot-Spots that would benefit most from mitigation actions.

This work reports on the main physical processes that arise in the environment of the megacity from the “urban metabolism”—the complex interactions of the climate with the activities performed in the city and its built structure and texture—as well as on associated large-scale processes that generate hazards for the megacity’s inhabitants. It is estimated that in a few decades most of the world’s population will live in urban centers. Both the growth of megacities and climate change will increase the vulnerability of huge sectors of the population to climatic consequences of the urban metabolism. These include urban heat islands, pollution, and extreme weather events such as heat waves and floods. Developing policies to mitigate these threats will require integrating scientific knowledge with management skills, communication among cities about effective approaches, and taking into account residents’ needs for health and the capacity to live safely.

At present, research activities on the role of orchard systems in sequestering atmospheric CO2 remain scarce. This paper aimed to contribute to assessing the carbon balance of a Mediterranean olive (Olea europea) orchard. The net ecosystem exchange, the ecosystem respiration and the gross primary production were computed for two consecutive years through eddy covariance, and the different biomass accumulation terms were also inferred in the same period through an inventorial method. The net carbon exchange ranged from 13. 45 t(C) ha-1 year-1 to 11. 60 t(C) ha-1 year-1. Very similar values [12. 2 and 11. 5 t(C) ha-1 year-1] were found with the direct carbon accumulation inventory. The intensive farming management (irrigation included) and the young age of the plants (12-16 years old), still in an active growing phase, led the olive plantation to be a higher carbon sink with respect to other evergreen orchards reported in the literature. © 2012 Springer Science+Business Media Dordrecht.

A characterization of local wind events in Mexico City, which occurred during MILAGRO campaign, was carried out within the framework of a lattice wind modeling approach at a meso-β scale. Mexico City was modeled as a 2D lattice domain with a given number of identical cells. Local wind conditions at any cell were described by a state variable defined by the spatial averages of wind attributes such as speed, direction, divergence, and vorticity. Full and partial densities of wind states were discussed under different conditions using two simple lattice wind models. We focus on the results obtained with the 1-cell lattice wind model and provide brief comments about preliminary results obtained with the 4-cell model. The 1-cell model allowed identifying the main patterns of the wind circulation in Mexico City throughout the study period (anabatic and katabatic winds, winds induced by the urban heat island, and winds with high possibilities for exchanging pollutants between Mexico City and the neighboring settlements, among others). The model showed that Mexico City wind divergence and vorticity disclose superposed oscillations whose most important periods were 24 and 12 hours, suggesting strong connections with the diurnal cycle of incoming solar radiation and the urban heat island.

Microbial aerosols (mainly composed by bacterial and fungal cells), may constitute up to 74 % of the total aerosol volume. These biological aerosols are relevant not only from the point of view of the dispersion of pathogenic species, but also due to the potential geochemical implications. Some bacteria and fungi may, in fact, serve as cloud condensation or ice nuclei, potentially affecting cloud formation and precipitation and are active at higher temperatures compared to their, much more intensively studied, inorganic counterparts. Simulations of the impact of microbial aerosols on climate are still hindered by the lack of information regarding their emissions from ground sources. This work tackles this knowledge gap by (i) applying a rigorous micrometeorological approach to the estimation of microbial net fluxes above a Mediterranean grassland and (ii) developing a deterministic model to estimate these emissions on the basis of a few easily recovered meteorological parameters (the PLAnET model). The grassland itself is characterized by an abundance of positive net microbial fluxes and the model proves to be a promising tool capable of capturing the day-to-day variability in microbial fluxes with a relatively small bias and sufficient accuracy. PLAnET is still in its infancy and will benefit from future campaigns extending the available training dataset as well as the inclusion of ever more complex and critical phenomena affecting the release of microbial aerosol (such as rainfall). The model itself is also adaptable as an emission module for dispersion and chemical transport models, allowing to further explore the impact of microbial aerosols on the atmosphere and climate.

This chapter addresses the problem of city resilience to climate change and to the applicable methodologies to improve the capacity to ameliorate the population wellbeing. Future scenarios of the physiological equivalent temperature indicate the magnitude of the phenomenon. The best available technologies to mitigate such problem seem to be the utilization of vegetation in open spaces, including roof top farming. The modelling of real cases demonstrate the effectiveness of such green improvements, encouraging policies to greenness.

in un mondo ormai trasformato dall'incremento di popolazione, temperatura ed inquinamento atmosferico la vegetazione si rivela una delle pietre angolari su cui costruire una citta' resilente

Architectural modification of existing urban morphology sometimes result as improvements of aesthetic characteristics of open spaces but could produce detriment of pre-existing wellness for residential population. An example of ex-ante/ex-post study allows assessing a methodology devoted to planners for the maximization of physiological wellbeing.

Si presenta il lungo processo di un Tavolo di lavoro che ha portato alla creazione di uno schema di certificazione di terza parte delle figure professionali del meteorologo e del tecnico meteorologo. Questo schema, ormai noto come schema DEKRA di certificazione, in quanto è DEKRA Testing & Certification che ha gestito questo iter, dalla valutazione dei titoli fino al rilascio del certificato professionale, consente al professionista di avere una visibilità internazionale riconosciuta del proprio lavoro collocandosi al livello degli altri professionisti dell'Unione Europea, permettendogli di cogliere più ampie opportunità di mercato. Il processo ha richiesto tempi lunghi, quasi tre anni, per poter accordare i diversi aspetti del settore meteorologico, coinvolgendo la formazione accademica, l'associazionismo internazionale, la formazione dell'Organizzazione Mondiale della Meteorologia (WMO), le figure che operano nelle Istituzioni della meteorologia e, in particolare, la figura dell'Ufficio del Rappresentante Permanente presso il WMO che ricopre il ruolo fondamentale di indirizzo e garanzia del rispetto delle raccomandazioni internazionali. In questo lavoro si analizzano tutti i passaggi chiave necessari per la messa a punto dello schema che rappresenta oggi un obiettivo di qualità per tutti i professionisti del settore meteorologico.

modellistica per la progettazione del benessere urbano

analisi dell'inquinamento dell'inverno 2015

analisi comparata del testo di legge realtivo al consumo di suolo

An experiment aimed at comparing particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) concentrations produced in a road tunnel by buses is described. The experiment took place in 2001 in Bologna when a couple of buses belonging to the public transport fleet where driven backwards and forwards in a road tunnel closed to all other vehicles. Buses run in the tunnel for 8 h a day for 4 experiment days, each day using a different fuel: biodiesel, diesel–water emulsion, diesel–water emulsion with low sulphur content and commercial diesel. Average daily concentrations of PM of different sizes and of 12 PHAs were measured and comparison between different fuels was attempted in order to assess “real-world” exhaust emissions of different fuels. Due to heterogeneity of experimental conditions in different days and the relatively large measurement uncertainties, the effort was only partially successful, and it was not possible to state any firm conclusion on fuels reliability even if some indications in agreement with literature were found. Nevertheless, the experiment and the data analysis method developed could be of interest as a methodological approach for future experiments aimed at evaluating “real-world” exhaust emissions of single vehicles.

¶The present work concerns measurements performed at five Polar sites in order to study the influence of cloud type and cloud cover on the surface radiative balance. Cloud cover index was retrieved with the Kasten and Czeplak formula (1980), and comparison with observed values showed the possibility of applying this formula in Polar regions. The Duchon and O’Malley (1999) methodology was adopted to estimate the cloud types present during the measurement period for each site. The results show that during the Antarctic summer clouds have a warming effect on the surface, while during a melting event recorded in the Arctic site clouds have a net cooling effect on the surface. This result allows us to conclude that, during a melting period a different cloud type formation, and a lower surface albedo, modify the effects of clouds on the surface radiation balance.

progettazione del comfort urbano e resilienza delle citta'. lezioni per REBUS II

Terrestrial gross primary productivity (GPP) varies greatly over time and space. A better understanding of this variability is necessary for more accurate predictions of the future climatecarbon cycle feedback. Recent studies have suggested that variability in GPP is driven by a broad range of biotic and abiotic factors operating mainly through changes in vegetation phenology and physiological processes. However, it is still unclear how plant phenology and physiology can be integrated to explain the spatiotemporal variability of terrestrial GPP. Based on analyses of eddycovariance and satellite-derived data, we decomposed annual terrestrial GPP into the length of the CO2 uptake period (CUP) and the seasonal maximal capacity of CO2 uptake (GPPmax). The product of CUP and GPPmax explained >90% of the temporal GPP variability in most areas of North America during 20002010 and the spatial GPP variation among globally distributed eddy flux tower sites. It also explained GPP response to the European heatwave in 2003 (r2 = 0.90) and GPP recovery after a fire disturbance in South Dakota (r2 = 0.88). Additional analysis of the eddycovariance flux data shows that the interbiome variation in annual GPP is better explained by that in GPPmax than CUP. These findings indicate that terrestrial GPP is jointly controlled by ecosystem-level plant phenology and photosynthetic capacity, and greater understanding of GPPmax and CUP responses to environmental and biological variations will, thus, improve predictions of GPP over time and space.

Simultaneous measurements of downwelling short-wave solar irradiance and incoming total radiation flux were performed at the Reeves Neve glacier station (1200 m MSL) in Antarctica on 41 days from late November 1994 to early January 1995, employing the upward sensors of an albedometer and a pyrradiometer. The downwelling short-wave radiation measurements were analysed following the Duchon and O'Malley [J. Appl. Meteorol. 38 (1999) 132] procedure for classifying clouds, using the 50-min running mean values of standard deviation and the ratio of scaled observed to scaled clear-sky irradiance. Comparing these measurements with the Duchon and O'Malley rectangular boundaries and the local human observations of clouds collected on 17 days of the campaign, we found that the Duchon and O'Malley classification method obtained a success rate of 93% for cirrus and only 25% for cumulus. New decision criteria were established for some polar cloud classes providing success rates of 94% for cirrus, 67% for cirrostratus and altostratus, and 33% for cumulus and altocumulus. The ratios of the downwelling short-wave irradiance measured for cloudy-sky conditions to that calculated for clear-sky conditions were analysed in terms of the Kasten and Czeplak [Sol. Energy 24 (1980) 177] formula together with simultaneous human observations of cloudiness, to determine the empirical relationship curves providing reliable estimates of cloudiness for each of the three above-mentioned cloud classes. Using these cloudiness estimates, the downwelling long-wave radiation measurements (obtained as differences between the downward fluxes of total and short-wave radiation) were examined to evaluate the downwelling long-wave radiation flux normalised to totally overcast sky conditions. Calculations of the long-wave radiation flux were performed with the MODTRAN 3.7 code [Kneizys, F.X., Abreu, L.W., Anderson, G.P., Chetwynd, J.H., Shettle, E.P., Berk, A., Bernstein, L.S., Robertson, D.C., Acharya, P., Rothman, L.S., Selby, J.E.A., Gallery, W.O., Clough, S.A., 1996. In: Abreu, L.W., Anderson, G.P. (Eds.), The MODTRAN 2/3 Report and LOWTRAN 7 MODEL. Contract F19628-91-C.0132, Phillips Laboratory, Geophysics Directorate, PL/GPOS, Hanscom AFB, MA, 261 pp.] for both clear-sky and cloudy-sky conditions, considering various cloud types characterised by different cloud base altitudes and vertical thicknesses. From these evaluations, best-fit curves of the downwelling long-wave radiation flux were defined as a function of the cloud base height for the three polar cloud classes. Using these relationship curves, average estimates of the cloud base height were obtained from the three corresponding sub-sets of long-wave radiation measurements. The relative frequency histograms of the cloud base height defined by examining these three sub-sets were found to present median values of 4.7, 1.7 and 3.6 km for cirrus, cirrostratus/altostratus and cumulus/altocumulus, respectively, while median values of 6.5, 1.8 and 2.9 km were correspondingly determined by analysing only the measurements taken together with simultaneous cloud observations.

Late frost are dangerous climatic hazards that can be responsible of fruit trees yield losses. Late frost potential hazard is, in particular, increased by the enhancement of low-temperature episodes in spring and to the concomitant early-blooming consequent to higher winter temperatures induced by the earth global warming. This paper reports observations on the micrometeorological features associated to frost occurrence in a representative area of the Po valley in order to characterize the atmospheric physics during frost formation episodes, to understand the frequency and the type of risk and to develop the most suitable protection practices. Energy balance and soil radiation balance are reported together with the main atmospheric features (air turbulence included), and the data-set collected are verified against the similarity equations. The computation of the surface roughness and the friction velocity, fundamental to the definition of the distinctive features of the site, has been also done by applying the similarity theory.

Experimental observations of anomalous extinction in rural fogs by means of trichromatic distant contrasts are explained in terms of Foitzik's suggestion about the loss of forward scattered daylight intercepted by the target.

During the Antarctic summer 1994/95 the values of downward and upward flux densities of both solar and terrestrial radiation were recorded at 1200 m for a period of 1 month on the Reeves Neve Glacier (lat 74°39′S, long 161°35′E), near the Italian base of Terra Nova Bay. The relations proposed by Swinbank [Swinbank, W.C., 1963. Long-wave radiation from clear skies. Q. J. R. Meteorol. Soc. 89, 339–348], Idso and Jackson [Idso, S.B., Jackson, R.D., 1969. Thermal radiation from the atmosphere. J. Geophys. Res. 74, 5397–5403] and Deacon [Deacon, E.L., 1970. The derivation of Swinbank's long-wave radiation formula. Q. J. R. Meteorol. Soc. 96, 313–319] associating the long-wave atmospheric radiation flux only to the air temperature at screen level were tested in extreme Antarctic climatological condition. A relation between the long-wave radiation flux and both screen air temperature and cloud cover fraction in accordance to the height of the cloud base was defined using the Kasten and Czeplak relationship that relates the solar radiation flux and the cloud cover index. The study of the incoming short-wave radiation flux from the clear sky and that reflected by the surrounding snow cover allowed for highlighting the role of surface geometry on the albedo measurements.

The development of a convective boundary layer over the Antarctic Plateau is documented by a Doppler minisodar data-set recorded during a 10 day campaign in January 1997. The vertical velocities associated with thermals do not exceed 1 m/s, while the depth of the convective layer, usually less than 200 m, never surpasses 300 m. Measurements of momentum flux, sensible heat flux, wind speed and radiation budget show characteristics that are typical of a convective boundary layer evolution. The diurnal behaviour of absolute humidity, however, exhibits features that are not expected, e.g. anticorrelation with incoming net radiation and air temperature.

This study presents a simple parameterisation for forecasting daytime net radiation in a Mexico City suburban area (Texcoco). The main characteristic of the parameterisation is that the only input data are the global solar radiation and air temperature trends. Reliability of the model was verified by measurements performed during two experimental campaigns carried out in 1992 and 1993 under a contract sponsored by the European Community. The forecast and the experimental data were found to agree very well even in disturbed meteorological situations.