Working papers

2026-5

Charbel ALKHOURY, César Ducruet, Magali Dumontet, Mariantonia Lo Prete, Barbara Polo Martin, Ling Sun, Sheng Zhang

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Abstract: This paper investigates the influence of multiple vessel traffics on air pollution and public health in European port cities. A sample of 120 Functional Urban Areas (FUAs) is analysed over the period 2000-2019, confronting container, cruise, liquid bulk, and solid bulk traffic with environmental (emissions of CO², PM2.5, NO²), public health (life expectancy, mortality rate), and socio-economic features like population density and GDP per inhabitant. Results from the fixed effects model show that population density is the major cause of all pollutions, followed by GDP and solid bulks, while life expectancy and mortality are mainly influenced by the nature of the local socio-economic environment (population density, age, GDP, bed rates, educational level). This is complemented by a factor analysis and a hierarchical clustering, which reveal the existence of three types of port cities: critical, tourism, and metropolitan. The typology of port cities is further discussed based on ground observation in particular sites.
Mot(s) clé(s): Europe; Functional Urban Area; hinterland; port city; sea transport; specialization; supply chains

2026-4

Thomas Jacquet

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Abstract: This article assesses the short- and medium-term effects of extreme heat on agricultural productivity across French departments during 1980-2023. Using high-resolution ERA5-Land temperature data and CORINE Land Cover, we construct a sector-specific Extreme Degree Days (EDD) index, weighted by cropland and pasture shares to capture sector-specific thermal stress. We estimate department-specific impulse responses via local projections and find significant and persistent productivity losses following heat shocks above 29 °C, with effects intensifying over a four-year horizon and attenuating only modestly thereafter. A Wald test confirms substantial regional heterogeneity in sensitivity to extreme temperatures. The negative impacts are particularly pronounced in lower-productivity, livestock-oriented departments clustered between 44.5° and 46° north latitude. These findings underscore the macroeconomic relevance of a spatially disaggregated measure of exposure to extreme temperatures and highlight the urgency of region-specific adaptation strategies as these episodes intensify.
Mot(s) clé(s): Agriculture; Climate change; Extreme heat; France; Productivity

2026-3

César Ducruet, Mariantonia Lo Prete

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Abstract: Europe as a whole is often regarded as a frontrunner in the domain of port-city sustainability, thanks to a wide set of international, national, and local initiatives. This paper is a review of local initiatives that are either individual (single port city) or collective (partnerships among several port cities), in the domains of energy transition and transport fluidity. We find that individual initiatives concentrate in northern Europe, in the largest ports, and at a few southern ones like Valencia or Marseilles. Conversely, collective actions are more concentrated in the south, including mostly small and medium-sized port cities, through projects financed by the European Commission. Besides, we show that port-urban congestion and PM2.5 pollution concentrate in the demographically and logistically largest port cities, which also dominate container throughput rankings and have the highest number of initiatives. We discuss the imperatives of ensuring a better regional balance across the continent and its port-city hierarchy.
Mot(s) clé(s): congestion; energy transition; Europe; population exposure; port cities; transport fluidity

2026-2

Georges Prat

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Abstract: An accounting measure of the demand for money is deduced from the Allais’ “Fundamental Equation of Monetary Dynamics”. Data from German hyperinflation in the early 1920s illustrate the method we propose. The spread between money supply and money demand is found to be rather moderate but is not white noise. Our approach can be applied to any country and over any period, provided that the aggregate expenditure can be approximated using available data. This new way can help improve the estimation of the money demand function while avoiding arbitrary assumptions about the dynamics of the spread between money supply and money demand.
Mot(s) clé(s): demand for money, measure

2026-1

Benjamin Trouve

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Abstract: Reaching global net-zero by 2050 requires rapidly scaling low-carbon hydrogen, but deployment is hindered by market uncertainty, high capital costs, and weak supply-demand coordination. This paper examines whether liberalizing international hydrogen and ammonia trade can accelerate deployment and how such policies interact with technological innovation. We develop a hybrid framework combining a global TIMES-based energy-system model (KiNESYS-IFPEN) with a stochastic logistic diffusion model calibrated to historical renewable energy growth under imperfect expectations. We find that trade liberalization alone has limited global impact, and mainly reallocates production geographically: the Middle East, North America, Latin America, and China expand as exporters, while Asia Pacific, Europe and Africa become structural importers. Innovation-driven electrolyzer cost reductions raise significantly global deployment success shifting production toward electrolysis. When policies are combined, innovation dominates, while trade openness reinforces regional specialization. These results underscore the central role of technological progress, credible expectations, and the trade-off between cost-efficient specialization and hydrogen supply security.
Mot(s) clé(s): Hydrogen, Trade Policies, Technology diffusion, TIMES-Markal model.

WORKING PAPERS 2026