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Some actions intended to adapt to climate change may do more harm than good, especially when they consume energy, making it more difficult to shift to decarbonized energy, or when, in meeting the needs of one group of people, they increase the vulnerability of others. Heat wave risk provides a typical example: air conditioning (AC) equipment may trigger large energy consumption and worsen outdoor heat stress. Alternative adaptation strategies exist, but it is not clear whether they can prevent the massive use of AC. Here, with an interdisciplinary modeling platform, taking Paris as a case study, we provide a first quantified analysis of the efficiency of adaptation strategies (large scale urban greening, building insulation policy, and generalized behavioral changes in AC use) in reducing future potential AC need. We find that even ambitious strategies do not appear sufficient to totally replace AC and ensure thermal comfort, under a median climate change scenario. They can, however, reduce AC energy use by half during heat waves and compensate for the heat released to the outdoor environment. Our results show that adaptation actions, implemented early, may play a key role if we are to remain on a low-carbon pathway.

The aim of this study was to examine the ability of a crop model forced by seasonal weather forecasts to anticipate correctly the agrometeorological variables affecting the growth of winter wheat in France. The method is based on wheat growth simulations over 199 sites in France for the period 1981–2005 driven by seasonal weather forecasts, consisting of 6 month long, 45 member hindcasts starting on 1 February. These simulations were challenging a climatologically based wheat growth forecasting system currently used by ARVALIS − Institut du vegetal. Both simulations were evaluated against a reference dataset. The simulations using the seasonal weather forecast present good skills for the dates of occurrence of the main growth stages: the ‘leaf sheaths strongly erect’ stage (also referenced as Zadoks scale Z30), the ‘head visible’ stage (Zadoks scale Z50) and the ‘kernel hard’ stage (Zadoks scale Z91). The simulations forced by the seasonal weather forecasts have lower bias than those forced by the climatological data: respectively −0.2 against 1.4 days for the Z30 stage, 1.1 against 3.2 days for the Z50 stage, 1.3 against 4.2 days for the Z91 stage. It is shown that the seasonal forecasting system provides more hit rates than the climatologically based method does. Thus, for the different events forecasted here, better predictability is found using the seasonal forecasting system. Despite shortcomings highlighted in this study, it is shown that a method based on seasonal weather forecasts could be applied in an operational context over France, in order to improve the method currently used in the agricultural sector.

The simulation of root water uptake in land surface models is affected by large uncertainties. The difficulty in mapping soil depth and in describing the capacity of plants to develop a rooting system is a major obstacle to the simulation of the terrestrial water cycle and to the representation of the impacts of drought. In this study, long time series of agricultural statistics are used to evaluate and constrain root water uptake models. The inter-annual variability of cereal grain yield and permanent grassland dry matter yield is simulated over France by the Interactions between Soil, Biosphere and Atmosphere, CO2-reactive (ISBA-A-gs) generic land surface model (LSM). The two soil profile schemes available in the model are used to simulate the above-ground biomass (Bag) of cereals and grasslands: a two-layer force–restore (FR-2L) bulk reservoir model and a multi-layer diffusion (DIF) model. The DIF model is implemented with or without deep soil layers below the root zone. The evaluation of the various root water uptake models is achieved by using the French agricultural statistics of Agreste over the 1994–2010 period at 45 cropland and 48 grassland départements, for a range of rooting depths. The number of départements where the simulated annual maximum Bag presents a significant correlation with the yield observations is used as a metric to benchmark the root water uptake models. Significant correlations (p value < 0.01) are found for up to 29 and 77% of the départements for cereals and grasslands, respectively. A rather neutral impact of the most refined versions of the model is found with respect to the simplified soil hydrology scheme. This shows that efforts should be made in future studies to reduce other sources of uncertainty, e.g. by using a more detailed soil and root density profile description together with satellite vegetation products. It is found that modelling additional subroot-zone base flow soil layers does not improve (and may even degrade) the representation of the inter-annual variability of the vegetation above-ground biomass. These results are particularly robust for grasslands, as calibrated simulations are able to represent the extreme 2003 and 2007 years corresponding to unfavourable and favourable fodder production, respectively.

Buildings’ energy systems release heat to the atmosphere that contributes to the urban heat island. In return, the energy demand from buildings depends on the meteorological conditions of their surroundings. Consequently, urban canopy models such as Town Energy Budget (TEB) have progressively included the representation of the main processes of building energetics: solar and internal heat gains, heat transmission through the enclosure and the heat exchange by infiltration and ventilation. The objective of this study is to extend the evaluation of the Building Energy Model (BEM) implemented in TEB. Five buildings representative of the morphological and thermal characteristics that can be encountered in European urban areas have been selected. The evaluation has been conducted with EnergyPlus building energy model and for two contrasted climates. The TEB model is able to estimate the heating and the cooling energy demand with an accuracy better than 5 kWh/m 2 /year for heating and 3 kWh/m 2 /year for cooling. This paper also discusses on the importance of computing the building's surrounding surface temperature for energy demand calculations. TEB is able to account for this effect whereas EnergyPlus assumes that building surroundings are at air temperature.

As the nonhydrostatic regional model of the Consortium for Small-Scale Modelling in Climate Mode (COSMO-CLM) is increasingly employed for studying the effects of urbanization on the environment, the authors extend its surface-layer parameterization by the Town Energy Budget (TEB) parameterization using the “tile approach” for a single urban class. The new implementation COSMO-CLM+TEB is used for a 1-yr reanalysis-driven simulation over Europe at a spatial resolution of 0.11° (~12 km) and over the area of Berlin at a spatial resolution of 0.025° (~2.8 km) for evaluating the new coupled model. The results on the coarse spatial resolution of 0.11° show that the standard and the new models provide 2-m temperature and daily precipitation fields that differ only slightly by from −0.1 to +0.2 K per season and ±0.1 mm day−1, respectively, with very similar statistical distributions. This indicates only a negligibly small effect of the urban parameterization on the model's climatology. Therefore, it is suggested that an urban parameterization may be omitted in model simulations on this scale. On the spatial resolution of 0.025° the model COSMO-CLM+TEB is able to better represent the magnitude of the urban heat island in Berlin than the standard model COSMO-CLM. This finding shows the importance of using the parameterization for urban land in the model simulations on fine spatial scales. It is also suggested that models could benefit from resolving multiple urban land use classes to better simulate the spatial variability of urban temperatures for large metropolitan areas on spatial scales below ~3 km.

A single-layer urban canopy model Community Land Model Urban (CLMU) is evaluated over two contrasting urban environments of Toulouse (France) and Melbourne (Australia). For the latter, three measurement sites are available characterized by a varying amount of vegetation, which supports a detailed assessment of the representation of urban vegetation in CLMU. For Toulouse, observed roof, wall and road surface temperatures allow for a detailed evaluation of the anthropogenic heat parameterization. Overall, CLMU performs well in simulating the canyon and urban surface temperatures, anthropogenic heat flux and urban energy balance, with an overall better performance for the dense old city centre of Toulouse in comparison to the more vegetated sites in Melbourne. Results for the latter sites reveal that the pervious road fraction provides a reasonable approximation of vegetation in the urban canyon while the tile approach often results in an underestimation of latent heat fluxes. A detailed analysis of the radiative, turbulent and anthropogenic heat fluxes as well as surface temperatures for Toulouse point to a complex interaction between urban surfaces and canyon properties. Decoupling the roof from the urban canyon to the atmosphere aloft is shown to be important. Our findings suggest that more evaluation is necessary for contrasting urban geometries in order to obtain a better understanding of the interaction between the roof surface on the one hand and canyon air and air aloft on the other hand. The results simultaneously reveal a trade-off in errors between surface temperatures, radiative and turbulent fluxes and anthropogenic heat which again stresses the importance of the intended model application. Also, our results suggest that model complexity should, perhaps, relate to the site complexity. These results provide a robust basis for the construction of additional sensitivity experiments, tailored towards the intended application for urban climate mitigation studies.

The increase in air temperature produced by urbanization, a phenomenon known as the urban heat island (UHI) effect, is often neglected in current building energy simulation practices. The UHI effect can have an impact on the energy consumption of buildings, especially those with low internal heat gains or with an inherent close interaction with the outdoor environment (e.g. naturally-ventilated buildings). This paper presents an urban weather generator (UWG) to calculate air temperatures inside urban canyons from measurements at an operational weather station located in an open area outside a city. The model can be used alone or integrated into existing programmes in order to account for the UHI effect in building energy simulations. The UWG is evaluated against field data from Basel (Switzerland) and Toulouse (France). The error of UWG predictions stays within the range of air temperature variability observed in different locations of the same urban area.

This paper presents an urban canopy and building energy model based on a thermal network of constant resistances and capacitances. The RC model represents the fundamental physical relations that govern the energy interactions between buildings and their urban environment, retaining the sensitivity to the design parameters typically used in building energy and urban climate studies. The benefits of the RC model are its simplicity and computational efficiency. It allows for better understanding the physics of the problem and makes it possible to easily evaluate modelling hypotheses and the sensitivity of different parameters. In this study, the RC model is evaluated against advanced simulation tools that are well accepted and evaluated within their individual scientific communities. The model is then used in a series of parametric analyses to investigate the impact of the Urban Heat Island effect on the energy consumption of buildings in configurations that are parameterized in terms of internal heat gains, construction, geometry, glazing ratio, and infiltration level. The RC model is also used to investigate the dominant mechanisms by which the indoor environment affects outdoor air temperatures. Parameters such as indoor air temperatures, exfiltration heat, and waste heat from HVAC systems are analysed. The conclusions obtained by this study can be applied to a wide range of urban configurations.

High resolution simulation of complex aerosol particle evolution and gaseous chemistry over an atmospheric urban area is of great interest for understanding air quality and processes. In this context, the CAPITOUL (Canopy and Aerosol Particle Interactions in the Toulouse Urban Layer) field experiment aims at a better understanding of the interactions between the urban dynamics and the aerosol plumes. During a two-day Intensive Observational Period, a numerical model experiment was set up to reproduce the spatial distribution of specific particle pollutants, from the regional scales and the interactions between different cities, to the local scales with specific turbulent structures. Observations show that local dynamics depends on the day-regime, and may lead to different mesoscale dynamical structures. This study focuses on reproducing these fine scale dynamical structures, and investigate the impact on the aerosol plume dispersion. The 500-m resolution simulation manages to reproduce convective rolls at local scale, which concentrate most of the aerosol particles and can locally affect the pollutant dispersion and air quality.

Within the framework of the international field campaign COPS (Convective and Orographically induced Precipitation Study), a large suite of state-of-the-art meteorological instrumentation was operated, partially combined for the first time. This includes networks of in situ and remote-sensing systems such as the Global Positioning System as well as a synergy of multi-wavelength passive and active remote-sensing instruments such as advanced radar and lidar systems. The COPS field phase was performed from 01 June to 31 August 2007 in a low-mountain area in southwestern Germany/eastern France covering the Vosges mountains, the Rhine valley and the Black Forest mountains. The collected dataset covers the entire evolution of convective precipitation events in complex terrain from their initiation, to their development and mature phase until their decay. Eighteen Intensive Observations Periods with 37 operation days and eight additional Special Observations Periods were performed, providing a comprehensive dataset covering different forcing conditions. In this article, an overview of the COPS scientific strategy, the field phase, and its first accomplishments is given. Highlights of the campaign are illustrated with several measurement examples. It is demonstrated that COPS research provides new insight into key processes leading to convection initiation and to the modification of precipitation by orography, in the improvement of quantitative precipitation forecasting by the assimilation of new observations, and in the performance of ensembles of convection-permitting models in complex terrain.

Concentrations and turbulent fluxes of accumulation mode particles were measured during the 2004–2005 ‘Canopy and Aerosol Particle Interaction in Toulouse Urban Layer’ project (CAPITOUL) at the top of two intersecting street canyons and in the urban boundary layer (UBL) in Toulouse, France. Particle numbers were strongly affected by boundary layer depth and showed limited sensitivity to local emissions. Differences in the diurnal patterns of particle numbers were observed between the finer fraction (0.3–0.4 μm) and coarser fraction (1.6–2.0 μm) of accumulation mode particles, indicating different processes of formation, evolution and transportation may be dominant. Highest particle numbers were observed in the narrow street canyon which had more limited local emissions and comparatively small particle fluxes. However, the improved ventilation rate in the wider canyon was also associated with the downward mixing of particles into the street canyon from the UBL. The results from this study clearly illustrate the temporal and spatial variability of particle numbers and fluxes in the urban atmosphere.

Experimental data of the energy balance and the turbulence network installed during the Convective and Orographically-induced Precipitation Study (COPS) field campaign of 2007 are presented in this study. The network aims at providing continuous surface flux and other surface micrometeorological data of the required high accuracy and quality for further fundamental research. An overview of the turbulence data processing and data quality control, including footprint analysis and a check for internal boundary layers, is given. The consistently applied approach allows for a high comparability of the turbulent flux data of sensible and latent heat. The reaction of surface fluxes during the observed frontal passage during the Intensive Observation Period (IOP) 9c (20 July 2007) is presented. As surface fluxes were measured over different land-use types and at different locations within the COPS area, the effect of land use and orography on turbulent fluxes is discussed with the help of IOP 8b (15 July 2007). The flux differences between individual sites due to varying surface characteristics are often larger than the flux differences with changing altitude. The oasis effect observed for the highly evapotranspirating maize fields is found to increase the residuum of the surface energy balance. At all sites and during both IOPs the occurrence of near-ground free convection conditions (FCCs) is investigated. During the oasis effect, FCCs do not occur. Copyright © 2011 Royal Meteorological Society

Urban land surface schemes have been developed to model the distinct features of the urban surface and the associated energy exchange processes. These models have been developed for a range of purposes and make different assumptions related to the inclusion and representation of the relevant processes. Here, the first results of Phase 2 from an international comparison project to evaluate 32 urban land surface schemes are presented. This is the first large-scale systematic evaluation of these models. In four stages, participants were given increasingly detailed information about an urban site for which urban fluxes were directly observed. At each stage, each group returned their models' calculated surface energy balance fluxes. Wide variations are evident in the performance of the models for individual fluxes. No individual model performs best for all fluxes. Providing additional information about the surface generally results in better performance. However, there is clear evidence that poor choice of parameter values can cause a large drop in performance for models that otherwise perform well. As many models do not perform well across all fluxes, there is need for caution in their application, and users should be aware of the implications for applications and decision making. Copyright  2010 Royal Meteorological Society

International audience; We describe a below-cloud scavenging module of aerosol particles by raindrops for use in a three-dimensional mesoscale cloud resolving model. The rate of particle removal is computed by integrating the scavenging efficiency over the aerosol particle and the drop size distributions. Here the numerical integration is performed accurately with a Gauss quadrature algorithm. The efficiency of the scavenging module is partially confirmed with experimental data. More interestingly, it is illustrated by two numerical experiments: the simulation of a forced convective circulation in a tropical cloudy boundary layer and a two-dimensional simulation of an African squall line. The results show a very selective wet removal of the aerosol particles which clearly depends on the mode radius, the width and the vertical profile of concentration. Furthermore, the squall line case shows the importance of resolving internal circulations to redistribute layers of aerosol particles in order to improve estimates of particle removal by below-cloud scavenging.

Cities interact with the atmosphere over a wide range of scales from the large-scale processes, which have a direct impact on global climate change, to smaller scales, ranging from the conurbation itself to individual buildings. The review presented in this paper analyzes some of the ways in which cities influence atmospheric thermodynamics and airborne pollutant transport. We present the main physical processes that characterize the urban local meteorology (the urban microclimate) and air pollution. We focus on small-scale impacts, including the urban heat island and its causes. The impact on the lower atmosphere over conurbations, air pollution in cities, and the effect on meteorological processes are discussed. An overview of the recent principal advances in urban climatology and air quality modeling in atmospheric numerical models is also presented.

International audience; The CAPITOUL experiment is a joint experimental effort in urban climate, including the energetic exchanges between the surface and the atmosphere, the dynamics of the boundary layer over the city and its interactions with aerosol chemistry. The campaign took place in the city of Toulouse in southwest France, for one year, from February 2004 to February 2005. This allowed the study of both the day-to-day and seasonal variability of urban climate processes. The observational network included surface stations (meteorology, energy balance, chemistry), profilers and, during intensive observing periods, aircraft and balloons. The urban Surface Energy Balance differs between summer and winter: in summer, the solar heat stored during the previous daytime period is enough to maintain the heat release at night, but in winter, almost all the energy comes from the anthropogenic heat released by space heating. Both processes produce the well known Urban Heat Island (UHI). The city is shown to impact the entire boundary layer on specific days, when an urban breeze is observed. In wintertime, fog is found to be modified due to the vertical structure of the nocturnal boundary layer above the city (which is slightly unstable and not stable). The measurements of aerosol properties in and downwind the city permitted documentation of the urban aerosol as well as the chemical transformation of these aerosols, in particular the ageing of carbonaceous aerosols during transport. The Toulouse aerosol is mainly composed of carbonaceous particles. There is important seasonal variation in the ratio of black carbon to organic carbon, in the concentration of sulfates and nitrates and in the related radiative aerosol impacts. SF6 was released as a tracer in a suburban area of Toulouse during anticyclonic conditions with weak winds. The tracer measurements show dispersion was mainly driven by the surface sensible heat flux, and was highly sensitive to the urban heat island and also to the transport of boundary layer clouds. Modeling was fully integrated into the campaign. Surface energy balance and urban boundary layer processes have already been used to complement the analyses of the physical processes observed during the campaign. Companion papers detail most of these observation or modeling studies.

The Town Energy Balance (TEB) scheme computes the surface energy balance for urban areas. It is intended to be coupled with atmospheric models for numerical weather prediction, air quality forecasts or research applications. Up to now, it has been evaluated for dry and hot seasons over light industrial (Vancouver) or dense urban (Mexico City, Marseille) areas. In this study, the evaluation of TEB is extended to two other seasons, fall and winter, using measurements conducted over a dense urban area of Toulouse (France) instrumented from February 2004 to March 2005. Most of the model outputs were measured (individual components of the net radiation, sensible heat flux) as well as state variables of the model (surface temperatures of roofs, roads, walls). Great care has been taken in the design of the surface temperature measurement strategy in order to provide comparable observations to modelled estimates. Focusing on the fall and winter season, this study also proposes an evaluation of the parameterization of anthropogenic heat sources against an inventory of energy consumption.

Resolution III fractional factorial designs are often used in the initial phases of an experiment to screen factors, but it may be desirable to include partial replication of the design to allow for the unbiased estimation of error while maintaining the orthogonality of the main effects. This paper proposes a new class of partially replicated two-level fractional factorial designs based on Hadamard matrices. Construction of these designs is discussed and their relative performance is evaluated by comparing them with competing fractional factorial designs.

The anthropogenic heat release, QF, has been estimated for the old European agglomeration of Toulouse (France) from February 2004 to March 2005 in the frame of the CAPITOUL experiment. Surface energy balance (SEB) measurements have been conducted at a downtown site, over a dense urban area. A method is proposed to estimate QF at the local scale around this site from observations, as the daily residual term of the SEB equation. The values obtained from this method are in agreement with what can be expected: QF estimates are around 70 W m−2 during winter and 15 W m−2 during summer. On a larger scale (that of the agglomeration), an energy consumption inventory was conducted for the period of the field campaign with a 1-day temporal resolution and a 100-m spatial resolution. The estimates of QF obtained with this second method were analysed at the local scale around the measurements site, and compared with estimates computed from the energy budget observations. For the winter period, both estimates are in good agreement. For the summer period, the method based on SEB measurements seems to underestimate QF which is estimated around 30 W m−2 from the inventory. The simultaneous estimate of QF, with these two independent methods is a strength of this study. At the scale of the agglomeration, the basal state of energy consumption (observed during the summer period) varies between 25 W m−2 for the densest areas to less than 5 W m−2 for the residential suburban areas. In the regions crossed by the major roads, the traffic is the major source during summer. Then during the winter period, QF can reach 100 W m−2 in the densest areas of Toulouse whereas it ranges between 5 and 25 W m−2 in the suburban areas. Copyright © 2007 Royal Meteorological Society

This study quantifies the processes that take place in the layer between the mean building height and the measurement level of an energy balance micrometeo- rological tower located in the dense old core of a coastal European city. The contribu- tions of storage, vertical advection, horizontal advection and radiative divergence for heat are evaluated with the available measurements and with a three-dimensional, high-resolution meteorological simulation that had been evaluated against observa- tions. The study focused on a summer period characterized by sea-breeze flows that affect the city. In this specific configuration, it appears that the horizontal advec- tion is the dominant term. During the afternoon when the sea breeze is well estab- lished, correction of the sensible heat flux with horizontal heat advection increases the measured sensible heat flux up to 100Wm −2 . For latent heat flux, the horizontal moisture advection converted to equivalent latent heat flux suggests a decrease of 50Wm −2 . The simulation reproduces well the temporal evolution and magnitude of

Data centers are most commonly cooled by air delivered to electronic equipment from centralized cooling systems. The research presented here is motivated by the need for strategies to improve and optimize the load capacity and thermal efficiency of data centers by using computational fluid dynamics (CFD). Here, CFD is used to model and optimize the Villanova Steel Orca Research Center (VSORC). VSORC, presently in the design stages, will provide a testing environment as well as the capability to investigate best practices and state of the art strategies including hybrid cooling, IT load distribution, density zones, and hot aisle and cold aisle containment. The results of this study will be used in the overall design and construction of the aforementioned research data center. The objective of this study is to find the optimal operating points and design layout of a data center while still meeting certain design constraints. A focus is on finding both the ideal total supply flow rate of the air conditioning units and the ideal chilled water supply temperature (CHWST) setpoint under different data center design configurations and load capacities. The total supply flow rate of the air conditioning units and the supply temperature setpoint of the chilled water system are varied as design parameters in order to systematically determine the optimal operating points. The study also examines the influence of hot aisle and cold aisle containment strategies in full containment, half containment, and no containment configurations on the determined optimal operating conditions for the modeled research data center.Copyright © 2015 by ASME

STUDY DESIGN: A retrospective consecutive case series, radiographic analysis, outcomes analysis, and report on complications. OBJECTIVES: To evaluate the radiographic and functional outcomes of a reconstructive realignment procedure for fixed sagittal imbalance and discuss the complications. SUMMARY OF BACKGROUND DATA: We describe a modification of an existing technique permitting greater single-level correction for which no reports exist in the peer-reviewed literature. METHODS: Twenty-four patients were eligible for 2-year minimum follow-up (average, 4.0 years). Etiologies included iatrogenic (n = 17), post-traumatic (n = 3), ankylosing spondylitis (n = 2), degenerative (n = 1), and congenital (n = 1). Patients were evaluated by standardized upright radiographs, chart review, and National Spine Network questionnaire. RESULTS: Seventeen patients had undergone 17 previous procedures. Seven of 24 patients required augmentation with anterior structural grafting. The majority of osteotomies were performed at L3 (15); others included L2 (6), L4 (2), and L5 (1). Lumbar lordosis before surgery averaged 13 degrees (range, 55 degrees to -65 degrees) and improved to 53 degrees (range, 20 degrees to 99 degrees), an average correction of 40%. The sagittal vertical axis measured from C7-S1 demonstrated a preoperative sagittal decompensation averaging 11.4 cm (range, 5.5-23 cm) with correction to 2.4 cm (-9.0 cm or 79% average correction). Coronal balance did not change significantly. There were 17 complications in 14 patients. Nine patients required additional surgery at latest follow-up. CONCLUSIONS: Transpedicular wedge resection osteotomy procedure is a very effective technique to correct fixed sagittal imbalance and provide biomechanical stability. The high complication rate mandates a careful assessment of the risk/benefit ratio before undertaking what is a major reconstructive procedure. Most patients are satisfied, particularly when sagittal balance is achieved.

3D numerical simulations with the Meso-NH atmospheric model including the Town Energy Balance urban parameterization, are conducted over the south-east of France and the one million inhabitants city of Marseille in the frameworks of the ESCOMPTE-UBL program. The geographic situation of the area is relatively complex, because of the proximity of the Mediterranean Sea and the presence of numerous massifs, inducing complex meteorological flows. The present work is focused on six days of the campaign, characterized by the development of strong summer sea-breeze circulations. A complete evaluation of the model is initially realized at both regional- and city-scales, by using the large available database. The regional evaluation shows a good behavior of the model, during the six days of simulation, either for the parameters near the surface or for the vertical profiles describing the structure of the atmosphere. The urban-scale evaluation indicates that the fine structure of the horizontal fields of air temperature above the city is correctly simulated by the model. A specific attention is then pointed to the 250-m horizontal resolution outputs, focused on the Marseille area, for two days of the campaign. From the study of the vertical structure of the Urban Boundary Layer and the thermodynamic fields near the surface, one underscores the important differences due to the regional and local flows, and the complex interactions that occur between the urban effects and the effects of sea breezes.

Surface and remote-sensing instruments deployed during ESCOMPTE experiment over the Marseille area, along the Mediterranean coast, were used to investigate the fine structure of the atmospheric boundary layer (ABL) during sea-breeze circulation in relation to pollutant transport and diffusion. Six sea-breeze events are analyzed with a particular focus on 25 June 2001. Advection of cool and humid marine air over land has a profound influence on the daytime ABL characteristics. This impact decreases rapidly with the inland distance from the sea. Nearby the coast (3 km inland), the mixing height Zi rises up to 750 m and falls down after 15:00 (UT) when the breeze flow reaches its maximum intensity. A more classical evolution of the ABL is observed at only 11-km inland where Zi culminates in the morning and stabilizes in the afternoon at about 1000 m height. Fine inspection of the data revealed an oscillation of the sea-breeze with a period about 2 h 47 min. This feature, clearly discernable for 3 days at least, is present in several atmospheric variables such as wind, temperature, not only at the ground but also aloft in the ABL as observed by sodar/RASS and UHF wind profilers. In particular, the mixing height Zi deduced from UHF profilers observations is affected also by the same periodicity. This pulsated sea-breeze is observed principally above Marseille and, at the northern and eastern shores of the Berre pond. In summary, the periodic intrusion over land of cool marine air modifies the structure of the ABL in the vicinity of the coast from the point of view of stability, turbulent motions and pollutants concentration. An explanation of the source of this pulsated sea-breeze is suggested.

Cet article analyse les impacts observés et projetés du changement climatique sur les systèmes humains et naturels, leur vulnérabilité et les possibilités d’adaptation. Il donne un aperçu des principaux résultats pour l’hydrologie, l’agriculture, les écosystèmes naturels, les infrastructures, le transport, l’énergie, le tourisme, la santé et les aspects sociaux. L’article reprend les principales conclusions du chapitre Europe de la contribution du Groupe II au 5e rapport du Giec paru en 2014. Plusieurs études traitant spécifiquement de la France métropolitaine sont également présentées, mais sans prétendre à l’exhaustivité, le sujet étant particulièrement vaste., This article analyses the observed and projected impacts of climate change on human and natural systems, their vulnerability and adaptation options. It provides insight into the main results related to hydrology, agriculture, natural ecosystems, transport, energy, tourism, infrastructures, health and social aspects. This article presents the main results concerning Europe that were compiled in the contribution of Working Group II to the IPCC fifth assessment report published in 2014. Several studies focused on mainland France are also presented, without claiming to be exhaustive.

International audience; Societies have to both reduce their greenhouse gas emissions and undertake adaptation measures to limit the negative impacts of global warming on the population, the economy and the environment. Examining how best to adapt cities is especially challenging as urban areas will evolve as the climate changes. Thus, examining adaptation strategies for cities requires a strong interdisciplinary approach involving urban planners, architects, meteorologists, building engineers, economists, and social scientists. Here we introduce a systemic modelling approach to the problem.Our four-step methodology consists of: first, defining interdisciplinary scenarios; second, simulating the long-term evolution of cities on the basis of socio-economic and land-use models; third, calculating impacts with physical models (such as TEB), and; finally, calculating the indicators that quantify the effect of different adaptation policies. In the examples presented here, urban planning strategies are shown to have unexpected influence on city expansion in the long term. Moreover, the Urban Heat Island should be taken into account in operational estimations of building energy demands. Citizens’ practices seem to be an efficient lever for reducing energy consumption in buildings.Interdisciplinary systemic modelling appears well suited to the evaluation of several adaptation strategies for a very broad range of topics.

Logistic regression is a popular method of relating a binary response to one or more potential covariables or risk factors. In 1980, Hosmer and Lemeshow proposed a method for assessing the goodness of fit of logistic regression models. This test is based on a chi-squared statistic that compares the observed and expected cell frequencies in the 2 g table, as found by sorting the observations by predicted probabilities and forming g groups. We have noted that the test may be sensitive to situations where there are low expected cell frequencies. Further, several commonly used statistical packages apply the Hosmer-Lemeshow test, but do so in diff erent ways, and none of the packages we considered alerted the user to the potential difficulty with low expected cell frequencies. An alternative goodness-of-fit test is illustrated which seems to off er an advantage over the popular Hosmer-Lemeshow test, by reducing the likelihood of small expected counts and, potentially, sharpening the interpretation. An example ...

When new vaccine products are marketed, they are generally supported by clinical studies lasting only a few years. The duration of protection from disease, however, is often expected to be considerably longer than the time spans of the clinical studies. Thus, there are both conceptual and methodological problems in trying to estimate long-term protection based on data from short-term clinical studies. We discuss the utility of predicting the duration of protection based on extrapolating observed antibody data. Several modeling strategies that have appeared in the clinical and statistical literature are reviewed. Two alternative mixed model strategies are considered and three methods of constructing confidence intervals for the mean duration of protection are proposed. Finally, a sample data set is used to illustrate and compare the various methods.

We consider the general case of probability prediction models having two or more outcomes and propose an adjusted X 2 statistic which can be used to assess the goodness of fit of these models. We present a simulation study to show that our proposed statistic has an approximate X 2 distribution under the null hypothesis. Two applications are provided to illustrate the use of the new statistic. The first application examines the fit of a logistic regression model using both the proposed statistic and the popular Hosmer-Lemeshow statistic and we compare and contrast these two methods. The second application evaluates the goodness of fit of a polychotomous regression model.

Recent papers examining the expected persistence of anti-hepatitis A virus antibody following vaccination with inactivated hepatitis A vaccine have estimated that geometric mean antibody levels will remain above cut-off levels for 10-30 years. However, the methodology used in these papers did not take into account any estimates of variability between subjects. In this paper data from the persistence of antibody after the administration of another vaccine, VAQTA (hepatitis A vaccine, inactivated; MSD), were used to develop further models of antibody decay. Using individual subject estimates instead of group means allowed the estimation of time to negativity for various percentiles of the population (including the median), and the construction of confidence intervals on estimates of time to negativity. Data from studies of subjects who seroreverted to negativity, and subsequently received a booster dose, were also considered to show that subjects who lose detectable antibody are likely to remain protected from hepatitis A disease by persistent immune memory and rapid anamnestic response soon after exposure to hepatitis A virus. The estimates of duration of protection suggest that VAQTA will provide protection for many years, first through presence of antibody and further through an anamnestic response based on persistent immune memory.

Created as an educational supplement, as the French monarchy declined, French children's literature quickly put itself at the service of the nation's dominant colonial policy. If the fabrication of...

Urban canopy models (UCMs) are being used as urban-climate prediction tools for different applications including outdoor thermal comfort and building energy consumption. To take advantage of their low computational cost, UCMs are often forced offline without being coupled to mesoscale atmospheric simulations, which requires access to meteorological information above the urban canopy layer. This limits the use of UCMs by other scientific and professional communities, such as building engineers and urban planners, who are interested in urban-climate prediction but may not have access to mesoscale simulation results or experimental meteorological data. Furthermore, the conventional offline use of UCMs neglects the fact that the urban boundary layer can be affected by the surface and that the same forcing conditions may not be suitable for studying different urban scenarios. This paper presents a physically based and computationally efficient methodology to calculate forcing air temperatures for UCMs from meteorological data measured at operational weather stations. Operational weather stations are available for most cities in the world and are usually located in open areas outside the cities. The proposed methodology is satisfactorily evaluated against mesoscale atmospheric simulations and field data from Basel, Switzerland, and Toulouse, France.

SURFEX is a new externalized land and ocean surface platform that describes the surface fluxes and the evolution of four types of surfaces: nature, town, inland water and ocean. It is mostly based on pre-existing, well-validated scientific models that are continuously improved. The motivation for the building of SURFEX is to use strictly identical scientific models in a high range of applications in order to mutualise the research and development efforts. SURFEX can be run in offline mode (0-D or 2-D runs) or in coupled mode (from mesoscale models to numerical weather prediction and climate models). An assimilation mode is included for numerical weather prediction and monitoring. In addition to momentum, heat and water fluxes, SURFEX is able to simulate fluxes of carbon dioxide, chemical species, continental aerosols, sea salt and snow particles. The main principles of the organisation of the surface are described first. Then, a survey is made of the scientific module (including the coupling strategy). Finally, the main applications of the code are summarised. The validation work undertaken shows that replacing the pre-existing surface models by SURFEX in these applications is usually associated with improved skill, as the numerous scientific developments contained in this community code are used to good advantage.

Urban metabolism considers a city as a system with flows of energy and material between it and the environment. Recent advances in bio-physical sciences provide methods and models to estimate local scale energy, water, carbon and pollutant fluxes. However, good communication is required to provide this new knowledge and its implications to endusers (such as urban planners, architects and engineers). The FP7 project BRIDGE (sustainaBle uRban plannIng Decision support accountinG for urban mEtabolism) aimed to address this gap by illustrating the advantages of considering these issues in urban planning. The BRIDGE Decision Support System (DSS) aids the evaluation of the sustainability of urban planning interventions. The Multi Criteria Analysis approach adopted provides a method to cope with the complexity of urban metabolism. In consultation with targeted end-users, objectives were defined in relation to the interactions between the environmental elements (fluxes of energy, water, carbon and pollutants) and socioeconomic components (investment costs, housing, employment, etc.) of urban sustainability. The tool was tested in five case study cities: Helsinki, Athens, London, Florence and Gliwice; and sub-models were evaluated using flux data selected. This overview of the BRIDGE project covers the methods and tools used to measure and model the physical flows, the selected set of sustainability indicators, the methodological framework for evaluating urban planning alternatives and the resulting DSS prototype.

The use of air-conditioning systems is expected to increase as a consequence of global-scale and urban-scale climate warming. In order to represent future scenarios of urban climate and building energy consumption, the Town Energy Balance (TEB) scheme must be improved. This paper presents a new building energy model (BEM) that has been integrated in the TEB scheme. BEM-TEB makes it possible to represent the energy effects of buildings and building systems on the urban climate and to estimate the building energy consumption at city scale (~10 km) with a resolution of a neighbourhood (~100 m). The physical and geometric definition of buildings in BEM has been intentionally kept as simple as possible, while maintaining the required features of a comprehensive building energy model. The model considers a single thermal zone, where the thermal inertia of building materials associated with multiple levels is represented by a generic thermal mass. The model accounts for heat gains due to transmitted solar radiation, heat conduction through the enclosure, infiltration, ventilation, and internal heat gains. BEM allows for previously unavailable sophistication in the modelling of air-conditioning systems. It accounts for the dependence of the system capacity and efficiency on indoor and outdoor air temperatures and solves the dehumidification of the air passing through the system. Furthermore, BEM includes specific models for passive systems, such as window shadowing devices and natural ventilation. BEM has satisfactorily passed different evaluation processes, including testing its modelling assumptions, verifying that the chosen equations are solved correctly, and validating the model with field data., French National Research Agency (ANR). MUSCADE project (ANR-09-VILL-003), European Commission Framework Program (FP7/2007–2013) (BRIDGE Project grant 211345)

The measurements of surface temperature are prone to important directional anisotropy in relation to the structure of the urban canopy and the radiative and energy exchanges inside it. Following the work of Lagouarde et al. 2010 that describes the daytime conditions, this paper focuses on the experimental analysis and modelling of the nighttime directional anisotropy. An extensive data set of airborne thermal infrared (TIR) measurements was collected over the city of Toulouse, France in the framework of the CAPITOUL project (Masson et al., 2008). The TIR measurements use a pair of thermal cameras equipped with wide angle lenses installed aboard a small aircraft. Three flights were made between 21:45 and 23:15 UTC, one in autumn and 2 in winter during 2004 and 2005 intensive operation periods (IOPs). The experimental results show that (i) the nighttime TIR directional anisotropy remains lower than 1°C for zenithal view angles up to 50°, and (ii) the nighttime anisotropy is insensitive to the azimuthal viewing direction. A modelling approach that combines a simplified 3D representation of the urban canopy with 2 energy transfer models, TEB and SOLENE, is then proposed. It confirms the experimental results quite well. Possible uncertainties on the geometry of the canopy and on most important thermo-radiative surface parameters are shown to have only little impact on the modelled TIR directional anisotropy. The time evolution of TIR anisotropy throughout night is simulated: for the fall and winter conditions studied the effects of thermal inertia completely vanish about 3 to 4 h after sunset, and the anisotropy never exceeds 2°C up to 60° zenithal view angles.

A consequence of urban heat islands in summer is an increase in the use of air conditioning in urbanized areas, which while cooling the insides of buildings, releases waste heat to the atmosphere. A coupled model consisting of a meso-scale meteorological model (MESO-NH) and an urban energy balance model (TEB) has been used to simulate and quantify the potential impacts on street temperature of four air conditioning scenarios at the scale of Paris. The first case consists of simulating the current types of systems in the city and was based on inventories of dry and evaporative cooling towers and free cooling systems with the river Seine. The other three scenarios were chosen to test the impacts of likely trends in air conditioning equipment in the city: one for which all evaporative and free cooling systems were replaced by dry systems, and the other two designed on a future doubling of the overall air conditioning power but with different technologies. The comparison between the scenarios with heat releases in the street and the baseline case without air conditioning showed a systematic increase in the street air temperature, and this increase was greater at nighttime than day time. It is counter-intuitive because the heat releases are higher during the day. This is due to the shallower atmospheric boundary layer during the night. The increase in temperature was 0.5 °C in the situation with current heat releases, 1 °C with current releases converted to only sensible heat, and 2 °C for the future doubling of air conditioning waste heat released to air. These results demonstrated to what extent the use of air conditioning could enhance street air temperatures at the scale of a city like Paris, and the importance of a spatialized approach for a reasoned planning for future deployment of air conditioning in the city.

Purpose To compare the efficacy and safety of tafluprost, a preservative-free (PF) prostaglandin analogue, with PF timolol in patients with open-angle glaucoma or ocular hypertension. Design Randomized, double-masked, multicenter clinical trial. Methods After discontinuation and washout of existing ocular hypotensive treatment, patients who had intraocular pressure (IOP) ≥23 and ≤36 mm Hg in at least 1 eye at the 08:00 hour time point were randomized 1:1 to 12 weeks of treatment with either PF tafluprost 0.0015% or PF timolol 0.5%. IOP was measured 3 times during the day (08:00, 10:00, 16:00 hours) at baseline and at weeks 2, 6, and 12. It was hypothesized that PF tafluprost would be noninferior to PF timolol over 12 weeks with regard to change from baseline IOP. The trial was powered for a noninferiority margin of 1.5 mm Hg at each of the 9 time points assessed. Results A total of 643 patients were randomized and 618 completed (PF tafluprost=306, PF timolol=312). IOPs at the 3 time points assessed during the baseline visit ranged from 23.8 to 26.1 mm Hg in the PF tafluprost group and 23.5 to 26.0 mm Hg in the PF timolol group. IOPs at the 3 time points assessed during the 12-week visit ranged from 17.4 to 18.6 mm Hg for PF tafluprost and 17.9 to 18.5 mm Hg for PF timolol. At all 9 time points, the upper limits of the 2-sided 95% confidence intervals for the difference between treatments in IOP lowering were less than the prespecified noninferiority margin. Similar percentages of PF tafluprost and PF timolol patients reported ocular pain/stinging/irritation (4.4% vs 4.6%) and pruritus (2.5% vs 1.5%). The percentages of PF tafluprost and PF timolol patients reporting conjunctival hyperemia were 4.4% vs 1.2% (nominal P = .016). Conclusions The IOP-lowering effect of PF tafluprost was noninferior to that of PF timolol. PF tafluprost is an efficacious and generally well-tolerated ocular hypotensive agent.

Objective: To document skin changes in the nipple during the 1st week of breastfeeding and to explore the relationship of such changes to pain. Design: Longitudinal descriptive study. Subjects were visited four times during the 1st week of breastfeeding. Sample: Convenience sample of 20 Caucasian women. Setting: Hospital and home. Main Outcome Measures: Observed skin characteristics of the nipple included erythema, edema, fissures, blisters, inflamed areas, eschar, white patches, dark patches, yellow patches, peeling, pus, and ecchymosis. Subject‐rated nipple pain. Results: Skin changes were identified and quantified. Changes were visible in 100% (20) of the sample, and 65% (13) had severe skin damage; 90% (18) of the subjects reported pain. Some correlations between skin characteristics and pain were statistically significant, but not clinically meaningful. Skin damage was concentrated on the tip of the nipple. Conclusions: The data chronicle skin changes and their relationship to nipple pain during the 1st week of breastfeeding. Normal neonatal sucking appears to induce a suction wound on the skin of the nipples of many breastfeeding women that may account for pain experienced at the onset of lactation.

Kinetic analysis of silicon nitridation requires intrinsic single-particle behaviour to be isolated from global or compact effects that typically manifest during the reaction-bonding process. These effects arise from the influence of adjacent particles, which modify the macropore structure as the reaction proceeds. Much of the variation in the published kinetic data can be attributed to compact effects, particle shape, and size distribution, resulting in a myriad of models being reported, each only applicable to the nitridation conditions in which the data were obtained. Our work clearly demonstrates that the intrinsic single-particle nitridation behaviour is well described by a sharp-interface model, with diffusion control (E a = 301.5–310.0 kJmol−1) through an expanding Si3N4 product layer developing on the individual grains. For the nitridation of silicon compacts, the reaction-bonding process can be divided into three fundamental stages: (1) initial devitrification/nucleation, (2) massive nitridation, and (3) termination by further sintering, densification, and coarsening of the Si3N4 product. Factors influencing and controlling each stage are summarized.

Several salient factors influencing the formation of reaction-bonded silicon nitride (RBSN) compacts have been studied. These include the effects of mullite and alumina furnace tubes typically employed during “high-purity” nitridation studies, pre-sintering of green silicon compacts, free powder versus compact nitridation, and the influence of metal/metal oxide additions. The latter studies have provided experimental evidence for enhancement due to dissociated nitrogen, and suggest that (1) β-Si3N4 formation does not necessarily require a liquid phase, (2) atomic nitrogen stimulates β-phase formation, and (3) the liquid phase provides an efficient source for volatile silicon, promoting α-Si3N4. These conclusions are consistent with accepted mechanisms for the formation of the two phases.

International audience; Facing the concern of the population to its environment and to climatic change, city planners are now considering the urban climate in their choices of planning. The use of climatic maps, such Urban Climate Zone--UCZ, is adapted for this kind of application. The objective of this paper is to demonstrate that the UCZ classification, integrated in the World Meteorological Organization guidelines, first can be automatically determined for sample areas and second is meaningful according to climatic variables. The analysis presented is applied on Toulouse urban area (France). Results show first that UCZ differentiate according to air and surface temperature. It has been possible to determine the membership of sample areas to an UCZ using landscape descriptors automatically computed with GIS and remote sensed data. It also emphasizes that climate behavior and magnitude of UCZ may vary from winter to summer. Finally we discuss the influence of climate data and scale of observation on UCZ mapping and climate characterization.

A large number of urban surface energy balance models now exist with different assumptions about the important features of the surface and exchange processes that need to be incorporated. To date, no comparison of these models has been conducted; in contrast, models for natural surfaces have been compared extensively as part of the Project for Intercomparison of Land-surface Parameterization Schemes. Here, the methods and first results from an extensive international comparison of 33 models are presented. The aim of the comparison overall is to understand the complexity required to model energy and water exchanges in urban areas. The degree of complexity included in the models is outlined and impacts on model performance are discussed. During the comparison there have been significant developments in the models with resulting improvements in performance (root-mean-square error falling by up to two-thirds). Evaluation is based on a dataset containing net all-wave radiation, sensible heat, and latent heat flux observations for an industrial area in Vancouver, British Columbia, Canada. The aim of the comparison is twofold: to identify those modeling approaches that minimize the errors in the simulated fluxes of the urban energy balance and to determine the degree of model complexity required for accurate simulations. There is evidence that some classes of models perform better for individual fluxes but no model performs best or worst for all fluxes. In general, the simpler models perform as well as the more complex models based on all statistical measures. Generally the schemes have best overall capability to model net all-wave radiation and least capability to model latent heat flux.