Articles | Volume 384
https://doi.org/10.5194/piahs-384-181-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/piahs-384-181-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Pre-conference publication
| 
16 Nov 2021
Pre-conference publication |
| 16 Nov 2021
| 16 Nov 2021
Investigating links between rainfall variations in the Ogooué River basin and ENSO in the Pacific Ocean over the period 1940–1999
Laboratory of Technology and Applied Sciences, University
Institute of Technology, P.O. Box 8698 Douala, Cameroon
LMI DYCOFAC, IRD, BP 1857 Yaoundé, Cameroon
Frédéric Frappart
LEGOS, Université de Toulouse, France, OMP, 14 Av. E.
Belin, 31400 Toulouse, France
Gil Mahé
HydroSciences Montpellier, Université de Montpellier,
300 Av. Pr E. Jeanbrau, Montpellier, France
Adrien Paris
Collecte Localisation Satellite (CLS), Ramonville-Saint-Agne, 31520
France
Raphael Onguene
Laboratory of Technology and Applied Sciences, University
Institute of Technology, P.O. Box 8698 Douala, Cameroon
Fabien Blarel
LEGOS, Université de Toulouse, France, OMP, 14 Av. E.
Belin, 31400 Toulouse, France
Fernando Niño
LEGOS, Université de Toulouse, France, OMP, 14 Av. E.
Belin, 31400 Toulouse, France
Jacques Etame
Département de Sciences de la Terre, Université de Douala, BP
24 157 Douala, Cameroon
Jean-Jacques Braun
LMI DYCOFAC, IRD, BP 1857 Yaoundé, Cameroon
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Thomas Legay, Yoann Aubert, Julien Verdonck, Jérémy Guilhen, Adrien Paris, Jean-Michel Martinez, Sabine Sauvage, Pankyes Datok, Vanessa Dos Santos, José Miquel Sanchez-Perez, Stéphane Bruxelles, Emeric Lavergne, and Franck Mercier
Proc. IAHS, 385, 477–484, https://doi.org/10.5194/piahs-385-477-2024, https://doi.org/10.5194/piahs-385-477-2024, 2024
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Water resources management traditionally relies on the use of in situ data. Spatial altimetry data is a new source of data for water resources monitoring. Through two projects, various partners (BRLi, IRD, CNES, CLS, CNRS, CENEAU) developed a method based on the combination of hydrological models, in-situ and satellite data to enhance the use of spatial altimetry data for water resources management. This article proposes to evaluate the implemented method.
Abderraouf Hzami, Oula Amrouni, Essam Heggy, Gil Mahé, and Hechmi Missaoui
Proc. IAHS, 385, 377–385, https://doi.org/10.5194/piahs-385-377-2024, https://doi.org/10.5194/piahs-385-377-2024, 2024
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Natural and anthropogenic causes of coastal environmental change are significantly linked to the sediment dynamics of the coastal lagoon on the North African coast, through both the variability of continental input and the coastal marine geomorphology. Temporal analysis of the aerial and orbital photogrammetry suggests that ~ 70 % of the Ghar El Melh coast.
Marc Auriol Amalaman, Gil Mahé, Béh Ibrahim Diomande, Armand Zamblé Tra Bi, Nathalie Rouché, Zeineddine Nouaceur, and Benoit Laignel
Proc. IAHS, 385, 365–370, https://doi.org/10.5194/piahs-385-365-2024, https://doi.org/10.5194/piahs-385-365-2024, 2024
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L’objectif de ce travail est d’analyser les liens entre les indices climatiques et la variabilité des séries de précipitations et de débits. La méthode a consisté à rechercher les changements survenus dans ces données à travers la variabilité du signal. Ainsi, au niveau de l’analyse interannuelle et saisonnière, le signal indique une forte oscillation marquée par une prédominance de la couleur rouge. L’utilisation de l’indice ENSO montre que le phénomène El-Niño impacte le débit et la pluie.
Domiho Japhet Kodja, Gandomè Mayeul Leger Davy Quenum, Houteta Djan'na Koubodana, Ernest Amoussou, Isaiah Sewanu Akoteyon, Arsène Sègla Josué Akognongbé, Mahougnon Fidèle Ahéhéhinnou Yêdo, Gil Mahé, Jean-Emmanuel Paturel, Expédit Wilfrid Vissin, and Constant Houndénou
Proc. IAHS, 385, 359–364, https://doi.org/10.5194/piahs-385-359-2024, https://doi.org/10.5194/piahs-385-359-2024, 2024
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The results showed that there is an variability in the spatial distribution of extreme indices with an upward and downward trend of dry and wet rainfall periods in West Africa in both historical and projected periods. Thus, the results revealed that the spatio- temporal variability of extreme rainfall can have repercussions on the hydrological functioning of watersheds, water availability and water-dependent activities.
Golab Moussa Omar, Jean-Emmanuel Paturel, Christian Salles, Gil Mahé, Mohamed Jalludin, Frédéric Satgé, Mohamed Ismail Nour, and Abdillahi Hassan Hersi
Proc. IAHS, 385, 59–64, https://doi.org/10.5194/piahs-385-59-2024, https://doi.org/10.5194/piahs-385-59-2024, 2024
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The Republic of Djibouti is a small country in the Horn of Africa and as with most regions of Africa, rain gauges are sparse. This study aims to compare at different time steps (annual, monthly, and daily) 15 rainfall estimation products (P-datasets) to 5 reference ground-based rainfall stations, over the period of 1980–1990. To classify the reliability of these products, several metrics were considered, the Kling Gupta Efficiency (KGE) and the Heidle Skills Scores (HSS at daily time step).
Ernest Amoussou, Félix Toundé Amoussou, Aymar Yaovi Bossa, Domiho Japhet Kodja, Henri Sourou Totin Vodounon, Constant Houndénou, Valérie Borrell Estupina, Jean-Emmanuel Paturel, Gil Mahé, Christophe Cudennec, and Michel Boko
Proc. IAHS, 385, 141–146, https://doi.org/10.5194/piahs-385-141-2024, https://doi.org/10.5194/piahs-385-141-2024, 2024
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The objective is to assess the causes of exceptional floods in the Ouémé basin using the HEC-RAS model. The results of the calculation made it possible to characterize: the losses and damage due to human settlement on the banks and agricultural production in the flood zone, the flooded extent and the height of submersion depend on the return period, most of the Flood waters converge towards the west of the basin (low risk) and towards the east around the Damè-Wogon depression (high risk).
Benjamin M. Kitambo, Fabrice Papa, Adrien Paris, Raphael M. Tshimanga, Frederic Frappart, Stephane Calmant, Omid Elmi, Ayan Santos Fleischmann, Melanie Becker, Mohammad J. Tourian, Rômulo A. Jucá Oliveira, and Sly Wongchuig
Earth Syst. Sci. Data, 15, 2957–2982, https://doi.org/10.5194/essd-15-2957-2023, https://doi.org/10.5194/essd-15-2957-2023, 2023
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The surface water storage (SWS) in the Congo River basin (CB) remains unknown. In this study, the multi-satellite and hypsometric curve approaches are used to estimate SWS in the CB over 1992–2015. The results provide monthly SWS characterized by strong variability with an annual mean amplitude of ~101 ± 23 km3. The evaluation of SWS against independent datasets performed well. This SWS dataset contributes to the better understanding of the Congo basin’s surface hydrology using remote sensing.
Heidi Kreibich, Kai Schröter, Giuliano Di Baldassarre, Anne F. Van Loon, Maurizio Mazzoleni, Guta Wakbulcho Abeshu, Svetlana Agafonova, Amir AghaKouchak, Hafzullah Aksoy, Camila Alvarez-Garreton, Blanca Aznar, Laila Balkhi, Marlies H. Barendrecht, Sylvain Biancamaria, Liduin Bos-Burgering, Chris Bradley, Yus Budiyono, Wouter Buytaert, Lucinda Capewell, Hayley Carlson, Yonca Cavus, Anaïs Couasnon, Gemma Coxon, Ioannis Daliakopoulos, Marleen C. de Ruiter, Claire Delus, Mathilde Erfurt, Giuseppe Esposito, Didier François, Frédéric Frappart, Jim Freer, Natalia Frolova, Animesh K. Gain, Manolis Grillakis, Jordi Oriol Grima, Diego A. Guzmán, Laurie S. Huning, Monica Ionita, Maxim Kharlamov, Dao Nguyen Khoi, Natalie Kieboom, Maria Kireeva, Aristeidis Koutroulis, Waldo Lavado-Casimiro, Hong-Yi Li, Maria Carmen LLasat, David Macdonald, Johanna Mård, Hannah Mathew-Richards, Andrew McKenzie, Alfonso Mejia, Eduardo Mario Mendiondo, Marjolein Mens, Shifteh Mobini, Guilherme Samprogna Mohor, Viorica Nagavciuc, Thanh Ngo-Duc, Huynh Thi Thao Nguyen, Pham Thi Thao Nhi, Olga Petrucci, Nguyen Hong Quan, Pere Quintana-Seguí, Saman Razavi, Elena Ridolfi, Jannik Riegel, Md Shibly Sadik, Nivedita Sairam, Elisa Savelli, Alexey Sazonov, Sanjib Sharma, Johanna Sörensen, Felipe Augusto Arguello Souza, Kerstin Stahl, Max Steinhausen, Michael Stoelzle, Wiwiana Szalińska, Qiuhong Tang, Fuqiang Tian, Tamara Tokarczyk, Carolina Tovar, Thi Van Thu Tran, Marjolein H. J. van Huijgevoort, Michelle T. H. van Vliet, Sergiy Vorogushyn, Thorsten Wagener, Yueling Wang, Doris E. Wendt, Elliot Wickham, Long Yang, Mauricio Zambrano-Bigiarini, and Philip J. Ward
Earth Syst. Sci. Data, 15, 2009–2023, https://doi.org/10.5194/essd-15-2009-2023, https://doi.org/10.5194/essd-15-2009-2023, 2023
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As the adverse impacts of hydrological extremes increase in many regions of the world, a better understanding of the drivers of changes in risk and impacts is essential for effective flood and drought risk management. We present a dataset containing data of paired events, i.e. two floods or two droughts that occurred in the same area. The dataset enables comparative analyses and allows detailed context-specific assessments. Additionally, it supports the testing of socio-hydrological models.
Benjamin Kitambo, Fabrice Papa, Adrien Paris, Raphael M. Tshimanga, Stephane Calmant, Ayan Santos Fleischmann, Frederic Frappart, Melanie Becker, Mohammad J. Tourian, Catherine Prigent, and Johary Andriambeloson
Hydrol. Earth Syst. Sci., 26, 1857–1882, https://doi.org/10.5194/hess-26-1857-2022, https://doi.org/10.5194/hess-26-1857-2022, 2022
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This study presents a better characterization of surface hydrology variability in the Congo River basin, the second largest river system in the world. We jointly use a large record of in situ and satellite-derived observations to monitor the spatial distribution and different timings of the Congo River basin's annual flood dynamic, including its peculiar bimodal pattern.
Moussa Moustapha, Loris Deirmendjian, David Sebag, Jean-Jacques Braun, Stéphane Audry, Henriette Ateba Bessa, Thierry Adatte, Carole Causserand, Ibrahima Adamou, Benjamin Ngounou Ngatcha, and Frédéric Guérin
Biogeosciences, 19, 137–163, https://doi.org/10.5194/bg-19-137-2022, https://doi.org/10.5194/bg-19-137-2022, 2022
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We monitor the spatio-temporal variability of organic and inorganic carbon (C) species in the tropical Nyong River (Cameroon), across groundwater and increasing stream orders. We show the significant contribution of wetland as a C source for tropical rivers. Thus, ignoring the river–wetland connectivity might lead to the misrepresentation of C dynamics in tropical watersheds. Finally, total fluvial carbon losses might offset ~10 % of the net C sink estimated for the whole Nyong watershed.
Rajae El Aoula, Gil Mahé, Nadia Mhammdi, Abdellatif Ezzahouani, Ilias Kacimi, and Kenza Khomsi
Proc. IAHS, 384, 163–168, https://doi.org/10.5194/piahs-384-163-2021, https://doi.org/10.5194/piahs-384-163-2021, 2021
Oula Amrouni and Gil Mahé
Proc. IAHS, 384, 133–139, https://doi.org/10.5194/piahs-384-133-2021, https://doi.org/10.5194/piahs-384-133-2021, 2021
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Our multidisciplinary study reveals an alarming trend of beach retreat reaching −20 m ± 0.15 m yr−1 after the human-induced change over the hydrological network where ~ 50 % of sediment discharge has been trapped upstream the dams. Accros the semi arid north African coasts, the rapid shoreline retreat is due to the decreasing of sediment fluvial discharge trapped by the dam infrastrcture.
Gil Mahé, Gamal Abdo, Ernest Amoussou, Telesphore Brou, Stephan Dietrich, Ahmed El Tayeb, Henny van Lanen, Mohamed Meddi, Anil Mishra, Didier Orange, Thi Phuong Quynh Le, Raphael Tshimanga, Patrick Valimba, Santiago Yepez, Andrew Ogilvie, and Oula Amrouni
Proc. IAHS, 384, 5–18, https://doi.org/10.5194/piahs-384-5-2021, https://doi.org/10.5194/piahs-384-5-2021, 2021
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The FRIEND-Water program (FWP) is the oldest and the most transverse program within the UNESCO IHP. It allows large communities of hydrologists to collaborate across borders on common shared data and scientific topics, addressed through 8 large world regions. Research priorities evolve according to the projections given by the member States during the IHP councils. FWP further activities follow the IHP IX program with the support of the Montpellier UNESCO Category II Center ICIREWAD.
Valentin Brice Ebodé, Gil Mahé, and Ernest Amoussou
Proc. IAHS, 384, 247–253, https://doi.org/10.5194/piahs-384-247-2021, https://doi.org/10.5194/piahs-384-247-2021, 2021
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The objective of this article is to assess recent trends of hydroclimatic quantities in Ogooue basin in the context of climate change. For this, the rainfall and discharges data of this basin were analyzed using the Pettitt test. The results of this study reveal a statistically significant decrease in runoff that the Pettitt test situates in 1972–73, but nothing like that for rainfall at this same time scale.
Valentin Brice Ebodé, Gil Mahé, and Ernest Amoussou
Proc. IAHS, 384, 261–267, https://doi.org/10.5194/piahs-384-261-2021, https://doi.org/10.5194/piahs-384-261-2021, 2021
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La sécheresse observée en Afrique tropicale vers la fin des années 1960, a également affecté le bassin de la Bénoué en Afrique centrale, avec une persistance remarquable qui s’est répercutée sur les écoulements. Les ruptures à la baisse ont été mises en évidence dans les séries hydropluviométriques de ce bassin au pas de temps annuel en 1970–71 (pluies) et 1971–72 (débits). Les déficits associés à cette rupture sont de −2,9 % pour les pluies et −14,2 % pour les débits.
Ernest Amoussou, Gil Mahe, Oula Amrouni, Ansoumana Bodian, Christophe Cudennec, Stephan Dietrich, Domiho Japhet Kodja, and Expédit Wilfrid Vissin
Proc. IAHS, 384, 1–4, https://doi.org/10.5194/piahs-384-1-2021, https://doi.org/10.5194/piahs-384-1-2021, 2021
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This short paper is the preface of the PIAHS volume of the IAHS/UNESCO FRIEND-Water conference of Cotonou in November 2021.
Golab Moussa Omar, Jean-Emmanuel Paturel, Christian Salles, Gil Mahé, and Mohamed Jalludin
Proc. IAHS, 384, 225–231, https://doi.org/10.5194/piahs-384-225-2021, https://doi.org/10.5194/piahs-384-225-2021, 2021
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Le district de Djibouti est situé dans le bassin versant de l’Oued Ambouli qui par sa nappe aquifère procure la source principale d’alimentation en eau potable de la ville de Djibouti, mais est aussi à l’origine de crues rares et brèves avec de lourds bilans humains et économiques Le développement du district se traduit par une expansion urbaine et un développement des activités qui accentuent le risque inondation.
Adama Telly Diepkilé, Flavien Egon, Fabien Blarel, Eric Mougin, and Frédéric Frappart
Proc. IAHS, 384, 31–35, https://doi.org/10.5194/piahs-384-31-2021, https://doi.org/10.5194/piahs-384-31-2021, 2021
Yves Tramblay, Nathalie Rouché, Jean-Emmanuel Paturel, Gil Mahé, Jean-François Boyer, Ernest Amoussou, Ansoumana Bodian, Honoré Dacosta, Hamouda Dakhlaoui, Alain Dezetter, Denis Hughes, Lahoucine Hanich, Christophe Peugeot, Raphael Tshimanga, and Patrick Lachassagne
Earth Syst. Sci. Data, 13, 1547–1560, https://doi.org/10.5194/essd-13-1547-2021, https://doi.org/10.5194/essd-13-1547-2021, 2021
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This dataset provides a set of hydrometric indices for about 1500 stations across Africa with daily discharge data. These indices represent mean flow characteristics and extremes (low flows and floods), allowing us to study the long-term evolution of hydrology in Africa and support the modeling efforts that aim at reducing the vulnerability of African countries to hydro-climatic variability.
Song Shu, Hongxing Liu, Richard A. Beck, Frédéric Frappart, Johanna Korhonen, Minxuan Lan, Min Xu, Bo Yang, and Yan Huang
Hydrol. Earth Syst. Sci., 25, 1643–1670, https://doi.org/10.5194/hess-25-1643-2021, https://doi.org/10.5194/hess-25-1643-2021, 2021
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This study comprehensively evaluated 11 satellite radar altimetry missions (including their official retrackers) for lake water level retrieval and developed a strategy for constructing consistent long-term water level records for inland lakes. It is a two-step bias correction and normalization procedure. First, we use Jason-2 as the initial reference to form a consistent TOPEX/Poseidon–Jason series. Then, we use this as the reference to remove the biases with other radar altimetry missions.
Yvan Gouzenes, Fabien Léger, Anny Cazenave, Florence Birol, Pascal Bonnefond, Marcello Passaro, Fernando Nino, Rafael Almar, Olivier Laurain, Christian Schwatke, Jean-François Legeais, and Jérôme Benveniste
Ocean Sci., 16, 1165–1182, https://doi.org/10.5194/os-16-1165-2020, https://doi.org/10.5194/os-16-1165-2020, 2020
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This study provides for the first time estimates of sea level anomalies very close to the coastline based on high-resolution retracked altimetry data, as well as corresponding sea level trends, over a 14-year time span. This new information has so far not been provided by standard altimetry data.
Fatima Hara, Mohammed Achab, Anas Emran, and Gil Mahe
Proc. IAHS, 383, 159–162, https://doi.org/10.5194/piahs-383-159-2020, https://doi.org/10.5194/piahs-383-159-2020, 2020
Ali Hadour, Gil Mahé, and Mohamed Meddi
Proc. IAHS, 383, 61–68, https://doi.org/10.5194/piahs-383-61-2020, https://doi.org/10.5194/piahs-383-61-2020, 2020
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The downward of rainfall trend occurred in the study area in 1972, affecting a few coastal stations. In 1976, this decline extended to the South West and throughout the coastal region. In 1980, the drop covered the entire basin. This decline has resulted in an estimated deficit of 30 % on average in the eastern region, the coastal region and the Mina. However, the central part of the basin experienced a 20 % decrease compared to the period before the break (1968–1980).
Domiho Japhet Kodja, Arsène J. Sègla Akognongbé, Ernest Amoussou, Gil Mahé, E. Wilfrid Vissin, Jean-Emmanuel Paturel, and Constant Houndénou
Proc. IAHS, 383, 163–169, https://doi.org/10.5194/piahs-383-163-2020, https://doi.org/10.5194/piahs-383-163-2020, 2020
Zhongbo Yu, Chunhui Lu, Jianyuan Cai, Dazheng Yu, Gil Mahe, Anil Mishra, Christophe Cudennec, Henny A. J. Van Lanen, Didier Orange, and Abou Amani
Proc. IAHS, 383, 3–4, https://doi.org/10.5194/piahs-383-3-2020, https://doi.org/10.5194/piahs-383-3-2020, 2020
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The 8th Global FRIEND conference highlighted the advance in hydrological science and innovation in water management. 52 accepted papers cover study areas in precipitation and climate impact; observation, analysis and simulations of hydrologic processes; floods in the changing environments; drought monitoring and analysis; water resources and environmental impacts. The outcome of the conference presented in the proceedings will be shared and discussed widely among UNESCO IHP networks.
Camille Jourdan, Valérie Borrell-Estupina, David Sebag, Jean-Jacques Braun, Jean-Pierre Bedimo Bedimo, François Colin, Armand Crabit, Alain Fezeu, Cécile Llovel, Jules Rémy Ndam Ngoupayou, Benjamin Ngounou Ngatcha, Sandra Van-Exter, Eric Servat, and Roger Moussa
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2019-116, https://doi.org/10.5194/hess-2019-116, 2019
Publication in HESS not foreseen
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In the theme Panta Rhei, this paper aims to develop a combined approach of data acquisition and a new semi-distributed non-stationary model taking into account land-use changes to reconstruct and predict annual runoff on an urban catchment in a data-sparse context. We use historical data and deploy a complementary short-term spatially-dense dedicated instrumentation. Applications were conducted on the tropical Mefou catchment (Yaoundé, Cameroon) to assess contributions of sub-catchments.
Ida Russo, Guillaume Ramillien, Frédéric Frappart, and Frédérique Rémy
The Cryosphere Discuss., https://doi.org/10.5194/tc-2019-16, https://doi.org/10.5194/tc-2019-16, 2019
Preprint withdrawn
Daniel D. Richter, Sharon A. Billings, Peter M. Groffman, Eugene F. Kelly, Kathleen A. Lohse, William H. McDowell, Timothy S. White, Suzanne Anderson, Dennis D. Baldocchi, Steve Banwart, Susan Brantley, Jean J. Braun, Zachary S. Brecheisen, Charles W. Cook, Hilairy E. Hartnett, Sarah E. Hobbie, Jerome Gaillardet, Esteban Jobbagy, Hermann F. Jungkunst, Clare E. Kazanski, Jagdish Krishnaswamy, Daniel Markewitz, Katherine O'Neill, Clifford S. Riebe, Paul Schroeder, Christina Siebe, Whendee L. Silver, Aaron Thompson, Anne Verhoef, and Ganlin Zhang
Biogeosciences, 15, 4815–4832, https://doi.org/10.5194/bg-15-4815-2018, https://doi.org/10.5194/bg-15-4815-2018, 2018
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As knowledge in biology and geology explodes, science becomes increasingly specialized. Given the overlap of the environmental sciences, however, the explosion in knowledge inevitably creates opportunities for interconnecting the biogeosciences. Here, 30 scientists emphasize the opportunities for biogeoscience collaborations across the world’s remarkable long-term environmental research networks that can advance science and engage larger scientific and public audiences.
Thouraya Benmoussa, Oula Amrouni, Laurent Dezileau, Gil Mahé, and Saâdi Abdeljaouad
Proc. IAHS, 377, 77–81, https://doi.org/10.5194/piahs-377-77-2018, https://doi.org/10.5194/piahs-377-77-2018, 2018
Ernest Amoussou, Henri S. Totin Vodounon, Expédit W. Vissin, Gil Mahé, and Marc Lucien Oyédé
Proc. IAHS, 377, 91–96, https://doi.org/10.5194/piahs-377-91-2018, https://doi.org/10.5194/piahs-377-91-2018, 2018
Fatma Kotti, Laurent Dezileau, Gil Mahé, Hamadi Habaieb, Malik Bentkaya, Claudine Dieulin, and Oula Amrouni
Proc. IAHS, 377, 67–76, https://doi.org/10.5194/piahs-377-67-2018, https://doi.org/10.5194/piahs-377-67-2018, 2018
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This study was designed to prove that the coastal changes of the Gulf of Tunis are mainly driven by the changes of the hydrological regime of the Medjerda river due to dams. We sampled cores of sediments in the low valley just before the sea, and analyzed them. They show the dramatic reduction of sediment supply after 1981, date of construction of the largest dam of Sidi Salem, and the disappearance of sand in the fluvial sediments.
Gil Mahe, Kate Heal, Akhilendra B. Gupta, and Hafzullah Aksoy
Proc. IAHS, 377, 1–1, https://doi.org/10.5194/piahs-377-1-2018, https://doi.org/10.5194/piahs-377-1-2018, 2018
Cassandra Normandin, Frédéric Frappart, Bertrand Lubac, Simon Bélanger, Vincent Marieu, Fabien Blarel, Arthur Robinet, and Léa Guiastrennec-Faugas
Hydrol. Earth Syst. Sci., 22, 1543–1561, https://doi.org/10.5194/hess-22-1543-2018, https://doi.org/10.5194/hess-22-1543-2018, 2018
Eghbert Elvan Ampou, Ofri Johan, Christophe E. Menkes, Fernando Niño, Florence Birol, Sylvain Ouillon, and Serge Andréfouët
Biogeosciences, 14, 817–826, https://doi.org/10.5194/bg-14-817-2017, https://doi.org/10.5194/bg-14-817-2017, 2017
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The 2015–2016 El Niño was the strongest on record and has generated significant coral bleaching and mortality worldwide. In Indonesia, first signs of bleaching were reported in April 2016. However, we show that this El Niño has impacted Indonesian reefs since 2015 through a different process than temperature-induced bleaching. Another El Niño-induced process, sea level fall, is responsible for significant coral mortality on North Sulawesi shallow reefs, and probably throughout Indonesia.
Rosemary Morrow, Alice Carret, Florence Birol, Fernando Nino, Guillaume Valladeau, Francois Boy, Celine Bachelier, and Bruno Zakardjian
Ocean Sci., 13, 13–29, https://doi.org/10.5194/os-13-13-2017, https://doi.org/10.5194/os-13-13-2017, 2017
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Spectral analyses of along-track altimetric data are used to estimate noise levels and observable ocean scales in the NW Mediterranean Sea. In winter, all altimetric missions can observe wavelengths down to 40–50 km (individual feature diameters of 20–25 km). In summer, SARAL can detect scales down to 35 km, whereas Jason-2 and CryoSat-2 with higher noise can only observe scales less than 50–55 km. Along-track altimeter data are also compared with collocated glider and coastal HF radar data.
Kenza Khomsi, Gil Mahe, Yves Tramblay, Mohamed Sinan, and Maria Snoussi
Nat. Hazards Earth Syst. Sci., 16, 1079–1090, https://doi.org/10.5194/nhess-16-1079-2016, https://doi.org/10.5194/nhess-16-1079-2016, 2016
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The study investigates trends in mean and extreme rainfall, run-off, temperature and their relationship with large-scale atmospheric circulation. It focuses on two Moroccan watersheds; Bouregreg and Tensift, using data from 1977 to 2003. Results do not show a homogeneous behaviour in the catchments; the influence of the large-scale atmospheric circulation is different and a clear spatial dependence of the trend analysis is linked to the distance from the coast and the mountains.
S. Taibi, M. Meddi, and G. Mahé
Proc. IAHS, 369, 175–180, https://doi.org/10.5194/piahs-369-175-2015, https://doi.org/10.5194/piahs-369-175-2015, 2015
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Short summary
Cette étude vise à analyser les tendances des pluies extrêmes dans un bassin semi-aride du Nord de l’Algérie et leur relation avec les types de circulation atmosphérique. Les pluies totales et l’intensité journalière ont connu une baisse significative durant la période 1971-2010 montre des tandis que leur fréquence ne montre pas de changement significatif.
L’oscillation méditerranéenne est le type de circulation qui influence la variabilité des pluies extrêmes du bassin du Chéliff
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Short summary
This paper investigates links between rainfall variability in the Ogooué River Basin (ORB) and El Niño Southern Oscillation (ENSO) in the Pacific Ocean. Recent hydroclimatology studies of the ORB and surrounding areas resulting in contrasting conclusions about links between rainfall variability and ENSO. Then, this work uses cross-wavelet and wavelet coherence analysis to highlight significant links between ENSO and rainfall in the ORB.
This paper investigates links between rainfall variability in the Ogooué River Basin (ORB) and...
