5 jeux de données trouvés

This map illustrates the satellite-detected water extent in Sindh, Balochistan, and Punjab Provinces, Pakistan, as observed from Sentinel-2 satellite images acquired on 31 July 2025 at 13:02 local time (08:02 UTC). Within the analyzed area of approximately 83,000 km², about 6,300 km² of land appears to be affected by floodwaters. The floodwater extent appears to have increased by approximately 1,300 km² since 11 July 2025. Based on WorldPop population data and the flood extent, approximately 2.3 million people are potentially exposed or living close to the flooded areas.

OpenLISEM is an open-source hydrological model suited for the simulation of floods, flash floods and erosion events. The following sections provide an overview of the results from the OpenLISEM model used in the exposure mapping A 30x30m flood map (maximum flood height) for the BuPuSa region was developed for several points on the intensity-frequency-duration curve. This curve represents the extreme value analysis (EVA) for the rainfall across the BuPuSa area. Based on 50 years of historic rainfall data from TAMSAT the EVA is developed for a 1000 year period. From this different rainfall intensities area taken which are referred to at the return period. The statistical possibility of a certain rainfall intensity to happen once in X many years. Flood maps were developed for the following return periods: 1/2, 1/10, 1/50, 1/100 and 1/1000. In addition to 5 different return periods, two different scenarios were modeled. A short high intensity rainfall event that typically causes flash floods, and a longer term lower intensity rainfall event that typically causes fluvial (river) floods. These events were represented by respectively a 6h rainfall event and a 14 day rainfall event. As a result 10 different flood maps were developed.

Zimbabwe is exposed to multiple weather-related hazards, suffering from frequent periodic cyclones, droughts, floods, and related epidemics and landslides. On 15 March 2019, tropical Cyclone Idai hit eastern Zimbabwe, and at least 172 deaths were reported, more than 186 people were injured and 327 were missing, while over 270,000 people were affected across nine districts, particularly in Chimanimani and Chipinge. Of those affected, 20,002 households (61.5%) or 100,106 people (74.2% of the 2012 population) were in Chimanimani. Meanwhile, ecosystem damage also occurred where boulders and mud were dumped downhill, affecting wildlife habitats, water quality, tourism activities and usability of land resources. The cyclone’s aftermath has therefore increased environmental risks, which will in turn affect local adaptation. Loss of vegetation cover means the natural defense against future flood waters and landslides is no longer available. Similar events in future are therefore likely to cause even more destruction. The overall objective of the initiative is therefore to reduce the vulnerability of communities in the Chimanimani and Chipinge Districts to natural disasters, such as floods, droughts and landslides; and to enhance water resource management as well as ecosystem services in response to the uncertainty of future climate change. The project is designed to approach the water-related risk and vulnerability through an integrated strategy that targets several aspects of disaster risk reduction, and provides scalable implementation of the project through a modular pathway and the development of case studies in target flood and landslide prone areas.

Le projet FRIEND/Nile, mis en œuvre en deux phases (2001-2006 et 2007-2013), visait à améliorer la gestion des ressources en eau du bassin du Nil grâce à la coopération régionale, au renforcement des capacités et à la recherche hydrologique appliquée. Lancé sous le Programme Hydrologique International (PHI) de l'UNESCO et financé par le gouvernement flamand de Belgique, le projet a impliqué des institutions clés de cinq pays du bassin du Nil : l'Égypte, le Soudan, l'Éthiopie, le Kenya et la Tanzanie. Le projet s'est concentré sur l'amélioration de la compréhension du régime hydrologique du fleuve par le biais de la coopération scientifique et de l'échange de données.

La Phase I (2001-2006) a établi la coopération technique et institutionnelle, mettant l'accent sur quatre composantes de recherche clés : la modélisation pluie-débit, le transport des sédiments et la gestion des bassins versants, l'analyse de la fréquence des crues et l'analyse des sécheresses et des faibles débits. Plus de 20 ateliers de formation et réunions techniques ont été organisés, renforçant les capacités des chercheurs et des institutions de la région. Le projet a facilité l'acquisition de données, le développement de modèles et la publication de rapports techniques, posant ainsi les bases d'une meilleure gouvernance transfrontalière de l'eau.

La Phase II (2007-2013) a élargi ces efforts en abordant de nouveaux défis tels que l'écohydrologie, la modélisation stochastique et l'érosion et le transport des sédiments. Des modèles hydrologiques avancés ont été introduits, le suivi des performances a été amélioré et les impacts du changement climatique sur la disponibilité de l'eau dans le bassin du Nil ont été évalués. Le projet a contribué à renforcer la coopération scientifique, à consolider les cadres institutionnels et à fournir des informations pertinentes pour soutenir la gestion durable des ressources en eau.