Séminaires 2017


Unraveling the effects of climate change and flow abstraction on an aggrading Alpine river

Séminaire de Maarten Bakker (Université de Lausanne), Jeudi 5 Octobre 2017 à 11h en Salle OSUG-B 105

Summary : Climatic warming and associated glacial retreat may have a large impact on sediment release and transfer in Alpine river basins. In parallel, the sediment transport capacity of many European Alpine streams is affected by hydropower exploitation, notably where flow is abstracted but the sediment supply to the headwaters is maintained. Here, I present the case-study of the Borgne River (Switzerland), where we reconstructed the historical evolution of bed level change and sediment (...)

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Risk of eutrophication in the Saigon River : impacts of the Ho Chi Minh City Megacity (Vietnam)

Séminaire de Nguyen Tuyet, jeudi 28 septembre à 14h en salle OSUG-B 105

Summary : This study aims at understanding natural and anthropogenic factors affecting the water quality of Saigon River. During nearly two years, we monitored the concentration of nutrients to assess the status of the river and the factors driving the water quality. Water body at Ho Chi Minh City presents high nutrient concentrations, which indicated an important release from the megacity. We evidenced that untreated domestic discharges lead to the degradation of Saigon River’s water (...)

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L’observation satellite peut-elle améliorer les modèles d’évolution du couvert nival ?

Séminaire de Alain ROYER, mardi 26 septembre 2017 à 11h, salle Llibourry, Bâtiment Glaciologie

Titre : L’observation satellite peut-elle améliorer les modèles d’évolution du couvert nival ?
Résumé : Cette présentation fait le point sur l’apport de la télédétection spatiale pour le suivi du couvert nival saisonnier, et sa contribution à l’amélioration des modèles de neige pour la prévision du futur. L’accent est mis sur le potentiel des micro-onde passives, une approche qui permet de remonter au volume de neige et sa masse (applications hydrologiques) et sur laquelle nous travaillons depuis de (...)

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High-resolution climate modelling

Séminaire de Thomas Jung, vendredi 22 septembre 2017 à 10 h, salle Lliboutry, bâtiment Glaciologie

Title : High-resolution climate modelling.
Abstract : In this presentation, recent progress at the AWI in high-resolution
climate modelling will be presented. The focus will be on the benefit of
sea ice-ocean modelling on unstructured meshes, which allows to
employing enhanced resolution in dynamically active regions, while
keeping a coarse resolution setup elsewhere. There results will be
discussed in terms of some long-standing model biases and the role of
enhanced resolution in climate (...)

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La mémoire du risque : Vaison-la-Romaine - 22 septembre 1992

Séminaire de Charles OBLED & Brice BOUDEVILLAIN, jeudi 21 septembre 2017 à 13 h- Salle OSUG-B 105

Il y a 25 ans, en ce début d’automne 1992, survenait la catastrophe de Vaison-la-Romaine. Différentes communautés scientifiques : météorologique, hydrologique, hydraulique torrentielle, géomorphologique se mobiliseront pour essayer de comprendre les différents aspects de l’évènement… A Grenoble, l’opération « Isère, Département pilote pour les risques majeurs » venait de nous doter d’un Pôle Grenoblois d’études et de recherches sur les Risques Naturels (PGRN, aujourd’hui PARN), et d’un Institut des Risques (...)

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Recent advances in understanding climate, glacier and river dynamics in high mountain Asia

Séminaire de Walter IMMERZEEL (Utrecht Univ.), jeudi 31 août 2017 à 11h, bâtiment Glaciologie, salle Lliboutry.

Abstract : The water cycle in the Himalaya is poorly understood because of its extreme topography that results in complex interactions between climate, water stored in snow and glaciers and the hydrological processes. Hydrological extremes in the greater Himalayas regularly cause great damage, while high mountain Asia also supplies water to over 25% of the global population. So, the stakes are high and an accurate understanding of the Himalayan water cycle is imperative. The hydrology of (...)

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Floods, Fires and Farming : Impacts of climate change in Latin America

Séminaire de Cerian GIBBES, vendredi 7 juillet 2017 à 10 h, salle 105 OSUG-B

Title : Floods, Fires and Farming : Impacts of climate change in Latin America
Brief abstract : Climate change is the greatest challenge facing the world in the 21st century. It is increasingly recognized that active engagement in decision making from a diverse set of stakeholders is needed to successfully respond to, and plan for, climate changes. This presentation will discuss an interdisciplinary and collaborative research effort to identify approaches and challenges associated with (...)

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Rapid decline of snow and ice in the tropical Andes – Impacts, uncertainties and challenges ahead

Séminaire de Mathias VUILLE, mercredi 5 juillet à 11h, salle Lliboutry, Bâtiment Glaciologie

Titre : Rapid decline of snow and ice in the tropical Andes – Impacts, uncertainties and challenges ahead.
Résumé : Glaciers in the tropical Andes have been retreating for the past several decades, leading to a temporary increase in dry season water supply downstream. Projected future glacier shrinkage, however, will lead to a long-term reduction in dry season river discharge from glacierized catchments. This glacier retreat is closely related to the observed increase in high-elevation, (...)

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Water Scarcity and Rioting : Disaggregated Evidence from Sub-Saharan Africa

Séminaire de Jérémy Laurent Lucchetti, jeudi 29 juin à 11h salle Lliboutry, Bâtiment Glaciologie

Résumé : It is often purported that unusually dry weather conditions provoke small-scale social conflict - riots - by intensifying the competition for water. The present paper explores this hypothesis, using data from Sub-Saharan Africa. We rely on monthly data at the cell level (0.5x0.5 degrees), an approach that is tailored to the short-lived and local nature of the phenomenon. Using a drought index to proxy for weather shocks (the SPEI), we find that a one-standard-deviation fall in the (...)

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