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The sudden interruption of recurring larch budmoth (LBM; Zeiraphera diniana or griseana Gn.) outbreaks across the European Alps after 1982 was surprising, because populations had regularly oscillated every 8–9 years for the past 1200 years or more. Although ecophysiological evidence was limited and underlying processes remained uncertain, climate change has been indicated as a possible driver of this disruption. An unexpected, recent return of LBM population peaks in 2017 and 2018 provides insight into this insect’s climate sensitivity. Here, we combine meteorological and dendrochronological data to explore the influence of temperature variation and atmospheric circulation on cyclic LBM outbreaks since the early 1950s. Anomalous cold European winters, associated with a persistent negative phase of the North Atlantic Oscillation, coincide with four consecutive epidemics between 1953 and 1982, and any of three warming-induced mechanisms could explain the system’s failure thereafter: (1) high egg mortality, (2) asynchrony between egg hatch and foliage growth, and (3) upward shifts of outbreak epicentres. In demonstrating that LBM populations continued to oscillate every 8–9 years at sub-outbreak levels, this study emphasizes the relevance of winter temperatures on trophic interactions between insects and their host trees, as well as the importance of separating natural from anthropogenic climate forcing on population behaviour. Electronic supplementary material The online version of this article (10.1007/s00442-019-04585-9) contains supplementary material, which is available to authorized users.

International audience

International audience

résumé résumérésumé; International audience

Adaptation des forêts au changement climatique : menaces et opportunités. 2. journée scientifique du projet environnemental CLIMIBIO

Sequential cropping (also known as multiple or double cropping) is a common feature, particularly for tropical regions, where the crop seasons are largely dictated by the main wet season such as the Asian summer monsoon (ASM). The ASM provides the water resources for crops grown for the whole year, thereby influencing crop production outside the ASM period. Land surface models (LSMs) typically simulate a single crop per year, however, in order to understand how sequential cropping influences demand for resources, we need to simulate all of the crops grown within a year in a seamless way. In this paper we implement sequential cropping in a branch of the Joint UK Land Environment Simulator (JULES) and demonstrate its use at Avignon, a site that uses the sequential cropping system and provides over 15-years of continuous flux observations which we use to evaluate JULES with sequential cropping. In order to implement the method in future regional simulations where there may be large variations in growing conditions, we apply the same method to four locations in the North Indian states of Uttar Pradesh and Bihar to simulate the rice--wheat rotation and compare model yields to observations at these locations. JULES is able to simulate sequential cropping at Avignon and the four India locations, representing both crops within one growing season in each of the crop rotations presented. At Avignon the maxima of LAI, above ground biomass and canopy height occur at approximately the correct time for both crops. The magnitudes of biomass, especially for winter wheat, are underestimated and the leaf area index is overestimated. The JULES fluxes are a good fit to observations (r-values greater than 0.7), either using grasses to represent crops or the crop model, implying that both approaches represent the surface coverage correctly. For the India simulations, JULES successfully reproduces observed yields for the eastern locations, however yields are under estimated for the western locations. This development is a step forward in the ability of JULES to simulate crops in tropical regions, where this cropping system is already prevalent, while also providing the opportunity to assess the potential for other regions to implement it as an adaptation to climate change.

Projections of grapevine phenophases under future climate change scenarios are strategic decision support tools for viticulturists and wine producers. Several phenological models are tested for budburst, flowering, and veraison and for two main grapevine varieties (cv. Touriga Franca and Touriga Nacional) growing in the Douro Demarcated Region. Four forcing models (Growing degree-days, Richardson, Sigmoid, and Wang) and three dormancy models (Bidabe, Smoothed Utah and Chuine), with different parameterizations and combinations, are used. New datasets, combing phenology with weather station data, widespread over the Douro wine region, were used for this purpose. The eight best performing models and parameterizations were selected for each phenophase and variety, based on performance metrics. For both cultivars, results revealed moderate performances (0.4 &lt, R2 &lt, 0.7) for budburst, while high performances (R2 &gt, 0.7) were found for flowering and veraison, particularly when Growing degree-days or Sigmoid models are used, respectively. Climate change projections were based on a two-member climate model ensemble from the EURO-CORDEX project under RCP4.5. Projections depicted an anticipation of phenophase timings by 6, 8 or 10&ndash, 12 days until the end of the century for budburst, flowering, and veraison, respectively. The inter-model variability is of approximately 2&ndash, 4 days for flowering and veraison and 4&ndash, 6 days for budburst. These results establish grounds for the implementation of a decision support system for monitoring and short-term prediction of grapevine phenology, thus promoting a more efficient viticulture.

This article describes extreme indices maps (Data Cube, raster X Time) for different scenarios with a more important contribution to the sea level rise from Greenland and/or Antarctica during the 21st century under the Representative Concentration Pathway (RCP) 8.5 emission scenario. The indices are produced annually and globally with a resolution of 0.5° × 0.5° from 1951 to 2099. The data were generated by simulating daily maximum and minimum temperature and precipitation from the IPSL-CM5A-LR model from Coupled Model Intercomparison Project Phase 5 (CMIP5). These climatic data are unbiased and downscaled to the 0.5°x0.5 scale with the Cumulative Distribution Function transform (CDFt) and EWEMBI dataset compiled to support the bias correction of climate input data for ISIMIP. Finally, each extreme indice is computed on the unbiased data on each grid cell on all continents. Keywords: Ice sheet contribution, Climate change, Extreme events, Temperature, Precipitation, Global climate model

National audience

Partie 3 : Douglas-fir ecology; International audience

Partie 3 : Douglas-fir ecology; International audience

Partie 4 : Management of Douglas-fir and technological properties of its wood; International audience

According to climate projections, global warming is associated with increasing temperatures and dry spells in some parts of the world, especially the Mediterranean area. However, it is quite challenging for the scientific community to assess the intensity of these changes, because (i) the trend relies on the greenhouse gases (GHG) emission scenario and (ii) fire occurrence depends on multiple factors (including climate, but not only). A proper assessment of the trend in terms of fire activity still lacks, especially for the French territory. Our study refines traditional approaches of fire risk projection under climate change by translating a danger index into potential fire activity (fire occurrence above 1 ha and burnt area).

International audience; Temperate plants are at risk of being exposed to late spring freezes. These freeze events—often called false springs—are one of the strongest factors determining temperate plants species range limits and can impose high ecological and economic damage. As climate change may alter the prevalence and severity of false springs, our ability to forecast such events has become more critical, and it has led to a growing body of research. Many false spring studies largely simplify the myriad complexities involved in assessing false spring risks and damage. While these studies have helped advance the field and may provide useful estimates at large scales, studies at the individual to community levels must integrate more complexity for accurate predictions of plant damage from late spring freezes. Here we review current metrics of false spring, and how, when and where plants are most at risk of freeze damage. We highlight how life stage, functional group, species differences in morphology and phenology, and regional climatic differences contribute to the damage potential of false springs. More studies aimed at understanding relationships among species tolerance and avoidance strategies, climatic regimes, and the environmental cues that underlie spring phenology would improve predictions at all biological levels. An integrated approach to assessing past and future spring freeze damage would provide novel insights into fundamental plant biology, and offer more robust predictions as climate change progresses, which is essential for mitigating the adverse ecological and economic effects of false springs.

This study provides an economic method to identify the impact of changes in stochastic (climatic) and non-stochastic (farm managed) inputs on the production of a representative sample of French field crop farms between 1990 and 2015. This economic decompositionmethod specifically attributes output changes to the impact of soil characteristics, climatic variables, non-stochastic farm managed inputs, and technological adaptation change. We quantify these impacts by decomposing product changes over time via Luenberger-type indicators, through a second-order flexible parametric technology estimation. We identify large disruptive effects due to climatic variables, especially since the beginning of this century., Cette étude fournit une méthodologie économique permettant d'identifier l'impact des modifications des intrants stochastiques (climatiques) et non stochastiques (gérés par les exploitations agricoles) sur la production d'un échantillon représentatif de grandes cultures françaises entre 1990 et 2015. Cette méthode de décomposition économique attribue spécifiquement les changements de production à l'impact des caractéristiques du sol, des variables climatiques, des intrants non stochastiques gérés par les exploitations et au changement de l'adaptation technologique. Nous quantifions ces impacts en décomposant l'évolution du produit dans le temps au moyen d'indicateurs de type Luenberger, avec une technologie paramétrique flexible de second ordre. Nous identifions des effets perturbateurs importants dus aux variables climatiques, en particulier depuis le début de ce siècle.

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Les sciences agronomiques ont incorporé ces dernières années un ensemble de mots clés et de concepts qui, parfois mal relayés ou utilisés hors contexte, peuvent être une source de malentendus sur l'origine et l'impact des actuels dérèglements environnementaux. L'objectif de ce rapport est de clarifier le cadre d'utilisation de cinq termes couramment utilisés dans les travaux concernant la dégradation des sols : équilibre, changement climatique, séquestration de carbone (C) dans les sols, résilience et 4 pour mille. Nous illustrons ces notions en utilisant des résultats obtenus par l'INRA en Guadeloupe sur la fertilité organique des sols.[br/] Nous traitons le concept d'équilibre sur la base des entrées et des sorties de matière organique (MO) du sol, lesquelles sont gérées par l'agriculteur via les pratiques culturales appliquées, et insistons sur le fait qu'il n'y a pas de "bons" et de "mauvais" équilibres. Le changement climatique perturbe cet équilibre en exacerbant les sorties (pertes) de MO dans la plupart des cas observés en Guadeloupe. Cette situation n'est pourtant pas irréversible car la séquestration de C peut être utilisée pour contrebalancer l'impact négatif du changement climatique, et assurer que la résilience du sol puisse jouer tout son rôle dans l'installation d'un phénomène de quasi-équilibre dynamique afin de préserver durablement la qualité du sol.[br/] Finalement, nous discutons l'initiative française du 4 pour mille, destinée à limiter le réchauffement climatique via la compensation des émissions de gaz à effet de serre. Cette initiative fait appel à la séquestration de C dans les sols afin de réduire le niveau de dioxyde de carbone (CO2) atmosphérique. Nous montrons que le 4 pour mille est d'application difficile à l'échelle du territoire guadeloupéen à cause des facteurs biophysiques et socioéconomiques. Son application à l'échelle locale (exploitation, petite région) requiert des incitations économiques afin de faire face aux coûts des intrants organiques nécessaires à sa mise en place. [br/]

Partie 3 : Douglas-fir ecology; International audience

International audience; center dot Key message Spring temperature increase is the main driver of larch tree wood formation onset along a 1000-m elevation gradient in the Southern Alps, while its cessation is more probably controlled by water stress at the lowest elevation and photoperiod at higher ones. center dot Context The survival of perennial plants depends on their adaptation to changing environment and specially temperature, which in trees is notably implemented through wood formation process. center dot Aims Our main objective is to understand how the phenology of wood formation is related to environmental factors and to temperature in particular. center dot Methods We monitored the xylogenesis of 60 larch trees, distributed in four stands along an elevation gradient of 1000 m in the French Southern Alps. center dot Results Cambial activity started around mid-May at the lowest site (1350 m) and around mid-June at the highest one (2300 m), showing a delay of 5.4 days per degrees C. The onset of wall-thickening and mature phenophases followed the same linear trend with a delay of 5.2 and 3 days per degrees C, respectively. Phenophase cessations followed a parabolic trend with trees from the lowest site finishing their growth the first, while those from 1700 m finished the last. Our results show that the onset of xylem formation is mainly driven by spring temperature increase, while its cessation is more related to photoperiod, with water shortage being able to hasten it. center dot Conclusion Future climatic changes will most probably increase growing season length (but not necessarily wood production) and shift upwards the optimal elevation for larch growth in the Southern Alps.

International audience; Extreme climatic events (ECEs) such as droughts and heat waves are predicted to increase in intensity and frequency and impact the terrestrial carbon balance. However, we lack direct experimental evidence of how the net carbon uptake of ecosystems is affected by ECEs under future elevated atmospheric CO2 concentrations (eCO2). Taking advantage of an advanced controlled environment facility for ecosystem research (Ecotron), we simulated eCO2 and extreme cooccurring heat and drought events as projected for the 2050s and analyzed their effects on the ecosystem-level carbon and water fluxes in a C3 grassland. Our results indicate that eCO2 not only slows down the decline of ecosystem carbon uptake during the ECE but also enhances its recovery after the ECE, as mediated by increases of root growth and plant nitrogen uptake induced by the ECE. These findings indicate that, in the predicted near future climate, eCO2 could mitigate the effects of extreme droughts and heat waves on ecosystem net carbon uptake.

National audience

International audience; The Mediterranean basin is a region of high biodiversity, marine and terrestrial, with important endemism. This diversity has faced long-lasting, strong and increasing human demographic pressure. The relatively more recent effects of climate change are well visible in the Mediterranean basin, with for example, heat wave and summer-drought related mortality on various species and ecosystems. The Mediterranean is then a model region for studying the consequences of climate change on biodiversity. Climate change, combined with land use change, may prove a particularly daunting adaptive challenge in the evolutionary, geomorphological and biogeographical context of the Mediterranean Basin. This semi-enclosed sea, its position and the succession of mountains and valleys over short distances, will limit range shift for both marine and terrestrial species. Millennia-old habitat destruction, fragmentation and abandonment of agriculture, urbanization, overharvesting and species introduction, will impact the evolutionary range and trajectories of marine and terrestrial species. We will discuss the potential of adaptation to climate change in Mediterranean ecosystems on the basis of studies on ecologically relevant terrestrial and marine species. After presenting the different modes of biological adaptation (acclimation and genetic adaptation), we will show how recent results, integrating genetics and ecology, allow to estimate the adaptive potential of these species. We will discuss the biological and ecological characteristics of these organisms which might favor or limit future adaptations, and the potential consequences on Mediterranean socio-ecosystems. We will consider terrestrial and marine ecosystems, such as forests and coralligenous habitats, as well as the interactions between land and sea. The social consequences, and the corresponding need to adapt management strategies, will also be taken into account.

Résumé; International audience

International audience

Effects of liming on greenhouse gas emissions in grasslands with contrasting soil types. EGU 2018, European Geophysical Union General Assembly 2018

International audience; Populations of fishes provide valuable services for billions of people, but face diverse and interacting threats that jeopardize their sustainability. Human population growth and intensifying resource use for food, water, energy and goods are compromising fish populations through a variety of mechanisms, including overfishing, habitat degradation and declines in water quality. The important challenges raised by these issues have been recognized and have led to considerable advances over past decades in managing and mitigating threats to fishes worldwide. In this review, we identify the major threats faced by fish populations alongside recent advances that are helping to address these issues. There are very significant efforts worldwide directed towards ensuring a sustainable future for the world’s fishes and fisheries and those who rely on them. Although considerable challenges remain, by drawing attention to successful mitigation of threats to fish and fisheries we hope to provide the encouragement and direction that will allow these challenges to be overcome in the future

Southwest Siberia encompasses the forest-steppe and sub-taiga climatic zones and has historically been utilized for agriculture. Coinciding with predicted changes in climate for the region is the pressure of agricultural development; however, a characterization of the soil water and carbon dynamics is lacking. We assessed current soil water properties and soil organic carbon turnover in forests and grasslands for two sites that span the forest steppe and sub-taiga bioclimatic zones. Soil evaporation was 0.62 ± 0.17 mm d−1 (mean ± standard error) in grasslands and 0.45 ± 0.08 mm d−1 in the forests of the forest-steppe site. Evaporation at the sub-taiga site was 1.80 ± 1.70 mm d−1 in grasslands and 0.96 ± 0.05 mm d−1 in forest plots. Evaporation was significantly greater at the sub-taiga site than the forest-steppe site. The density of fine roots explained the soil water isotopic patterns between vegetation types and sites. We found soil organic matter turnover to be three times faster in the sub-taiga site than in the forest-steppe site. Our results show that while climate factors, in particular snow levels, between the two sites are drivers for water and carbon cycles, site level hydrology, soil characteristics, and vegetation directly interact to influence the water and carbon dynamics.

International audience

L’impact du changement climatique sur la qualité et la pollution des milieux est souvent négligé par rapport à d’autres impacts plus médiatisés (e.g. événements climatiques et hydrologiques extrêmes, santé, trait de côtes, disponibilité des ressources en eau…). Les eaux et l’air de Nouvelle-Aquitaine, et à moindre mesure les sols, déjà significativement pollués, subiront pourtant plusieurs détériorations significatives, qui sont présentées et discutées dans ce chapitre. Certains de ces effets sont déjà visibles et vont s’aggraver dans le contexte climatique prévu. Il s’agit principalement, pour l’eau douce superficielle, de l’augmentation de la température, de la diminution des débits des cours d’eau, de l’évolution des espèces aquatiques et du développement accru de micro-organismes de type cyanophycées, ou pour l’air, de l’augmentation de l’index pollinique et des effets néfastes croissants sur la santé publique. Bien que non réellement démontrés in situ en région, d’autres effets sont fortement prévisibles, comme la diminution de la matière organique des sols et de leur fertilité, l’augmentation des teneurs en polluants dans toutes les masses d’eau, l’augmentation de l’écotoxicité des eaux de surface et l’augmentation de la concentration en ozone dans l’air et autres composés organiques volatils et aérosols. Les travaux de recherche et études sur cette problématique au niveau régional, comme national, sont rares et/ou peu publiés. Une recherche appliquée au « terrain » de la Nouvelle-Aquitaine, sur des sites d’observation scientifiquement et économiquement sélectionnés, est indispensable pour évaluer plus clairement ces impacts du changement climatique, mais également les adaptations à préconiser et les enjeux environnementaux et socio-économiques qui en découleront.

La région Nouvelle-Aquitaine est l’une des plus grandes régions agricoles en Europe. Elle abrite une agriculture très diversifiée avec de nombreuses productions emblématiques comme le vin et le cognac, le maïs et le blé ou encore les fruits, et un élevage de haute qualité. Le secteur agricole sera d’autant plus affecté par le changement climatique que la hausse des températures pourrait être plus importante dans le quart Sud Ouest de la France. Les ressources de base, à savoir le sol et l’eau, tout comme l’élevage et les cultures sont sensibles aux changements climatiques et sociétaux ; la recrudescence des risques sanitaires en est un contrecoup. En fonction des cultures et des productions animales considérées, les répercussions seront variées, quelquefois positives mais le plus souvent négatives, avec des constantes sur la précocité, le rendement, et la qualité des produits récoltés. Pour chacune de ces productions, il existe des adaptations possibles qui doivent être combinées pour maintenir le potentiel productif et qualitatif, tout en minimisant l’impact environnemental. Les mesures contribuant à la fois à réduire l’émission de gaz à effet de serre par le secteur agricole et à s’adapter aux changements irrémédiables du climat devront être favorisées. L’irrigation devra être questionnée et gérée en adéquation avec l’ensemble des usages de l’eau. Pour répondre aux enjeux auxquels doit faire face l’agriculture en Nouvelle-Aquitaine, il sera important de mobiliser tous les acteurs du monde agricole, des filières et des territoires, et de la recherche.

There are many factors that influence ecosystem scale carbon, nitrogen and greenhouse gas dynamics, including the inherent heterogeneity of soils and vegetation, anthropogenic management interventions, and biotic and abiotic disturbance events. It is important therefore, to document the characteristics of the soils and vegetation and to accurately report all management activities, and disturbance events to aid the interpretation of collected data, and to determine whether the ecosystem either amplifies or mitigates climate change. This paper outlines the importance of assessing both the spatial and temporal variability of soils and vegetation and to report all management events, the import or export of C or N from the ecosystem, and the occurrence of biotic/abiotic disturbances at ecosystem stations of the Integrated Carbon Observation System, a pan-European research infrastructure.

National audience

Management and remediation actions of polycyclic aromatic hydrocarbons (PAH) contaminated sites require an accurate knowledge of the dynamics of these chemicals in situ under real conditions. Here we developed, under the Virtual Soil Platform, a global model for PAH that describes the principal physical and biological processes controlling the dynamics of PAH in soil under real climatic conditions. The model was applied first to simulate the observed dynamics of phenanthrene in situ field experimental plots of industrial contaminated soil. In a second step, different long-term scenarios of climate change or bioavailability increase were applied. Our results show that the model can adequately predict the fate of phenanthrene and can contribute to clarify some of unexplored aspects regarding the behavior of phenanthrene in soil like its degradation mechanism and stabilization. Tested prospective scenarios showed that bioavailability increase (through the addition of solvent or surfactants) resulted in significant increase in substrate transfer rate, hence reducing remediation time. Regarding climate change effect, the model indicated that phenanthrene concentration decreased by 54% during 40 years with a natural attenuation and both scenarios chosen for climatic boundaries provided very similar results.

Master; D’ici à la fin du siècle, la poursuite du changement climatique provoquerait en France une augmentation de la fréquente et de l’intensité d’évènements climatiques extrêmes combinant des canicules et des sécheresses. Ces extrêmes climatiques peuvent remodeler les services écosystémiques des prairies. La résilience des prairies à des stress extrêmes est un enjeu important puisque la production de fourrage représente la majorité de la ration alimentaire des herbivores. Cette résilience est conditionnée par la récupération des espèces présentes dans la communauté. Ce travail a permis d’étudier la résistance à la sécheresse et la récupération après réhydratation des types fonctionnels des communautés végétales d’une prairie permanente de moyenne montage soumise à différents scénarii de manipulations des précipitations (totale ou partielle). La simulation de deux types de sécheresse nous a montré des effets différents pour chaque sécheresse sur la production fourragère en quantité et en qualité, la composition en groupes fonctionnels et sur la récupération. La sécheresse extrême simulée conduit pour le traitement P69 à un changement d’état de la végétation. La biomasse a diminué dans les deux expérimentations mais cette baisse n’a pas été compensée par la présence de trois types fonctionnels parce qu’ils ont été négativement affectés par certains traitements climatiques. La saisonnalité d’occurrence de la sécheresse a été étudiée et nous l’avons remarqué avec la diminution de la teneur en eau du sol mais pas avec la diminution de la biomasse. Une réduction de la biomasse a été observée pour les traitements SU et SPSU mais aucun effet significatif pour le traitement SP. Une baisse de la biomasse des légumineuses a été mise en évidence uniquement pour la coupe fréquente. La production de cette prairie a montré une résistance et une récupération au cours du traitement « coupe peu fréquente ». Cela nous amenant à dire qu’une gestion extensive permettrait une meilleure résistance et récupération des prairies face aux perturbations climatiques.

Article en open access; International audience; Purpose of Review Climate change affects populations of forest insect pests in a number of ways. We reviewed the most recent literature (2013-2017) on this subject including previous reviews on the topic. We provide a comprehensive discussion of the subject, with special attention to insect range expansion, insect abundance, impacts on forest ecosystems, and effects on forest insect communities. We considered forest insects according to their major guilds and biomes. Recent Findings Effects of climate change on forest insects are demonstrated for a number of species and guilds, although generalizations of results available so far are difficult because of species-specific responses to climate change. In addition, disentangling direct and indirect effects of climate change is complex due to the large number of variables affected. Modeling based on climate projections is useful when combined with mechanistic explanations. Summary Expansion of either the true range or the outbreak range is observed in several model species/groups of major insect guilds in boreal and temperate biomes. Mechanistic explanations are provided for a few species and are mainly based on increase in winter temperatures. In relation to insect abundance, climate change can either promote outbreaks or disrupt trophic interactions and decrease the severity of outbreaks. There is good evidence that some recent outbreaks of bark beetles and defoliating insects are influenced by climate change and are having a large impact on ecosystems as well as on communities of forest insects.

National audience

Vulnerability assessment to climate change is an issue of concern.We develop Java-based software for vulnerability assessment to climate change.We illustrate the software in vulnerability assessments of European grasslands. Vuln-Indices Java-based software was developed on concepts of vulnerability to climate change of agro-ecological systems. It implements the calculation of vulnerability indices on series of state variables for assessments at both site and region levels. The tool is useful because synthetic indices help capturing complex processes and prove effective to identify the factors responsible for vulnerability and their relative importance. It is suggested that the tool may be plausible for use with stakeholders to disseminate information of climate change impacts.

National audience

Many studies have used epidemic models in conjunction with climate change projections to predict the effects of climate on plant pests, but have focused on the effects of average air temperature, humidity and rainfall. However, in most scenarios climate change is expected to increase the variability in climatic parameters, leading to potentially more extreme records in temperature, rainfall, or drought periods. In this paper, we studied the survival capacity of the anthracnose pathogen Colletotrichum gloesporioides infecting water yam (Dioscorea alata) to prolonged dry periods (6 to 48h) and supraoptimal temperatures (36 to 40°C). Our results show that i) spores of C. gloeosporioides can survive in the absence of leaf wetness for up to 48h and recover a high infectious capacity when water is provided subsequently, and ii) infectious capacity is recovered after high temperature stress of up to 40°C, depending on the strain.

résumé; International audience

résumé; National audience

National audience

National audience

International audience