Twenty-three unsolved problems in hydrology (UPH) - a community perspective

Bloeschl, Gunter
Bierkens, Marc F. P.
Chambel, Antonio
Cudennec, Christophe
Destouni, Georgia
Fiori, Aldo
Kirchner, James W.
McDonnell, Jeffrey J.
Savenije, Hubert H. G.
Sivapalan, Murugesu
Stumpp, Christine
Toth, Elena
Volpi, Elena
Carr, Gemma
Lupton, Claire
Salinas, Jose
Szeles, Borbala
Viglione, Alberto
Aksoy, Hafzullah
Allen, Scott T.
Amin, Anam
Andreassian, Vazken
Arheimer, Berit
Aryal, Santosh K.
Baker, Victor
Bardsley, Earl
Barendrecht, Marlies H.
Bartosova, Alena
Batelaan, Okke
Berghuijs, Wouter R.
Beven, Keith
Blume, Theresa
Bogaard, Thom
de Amorim, Pablo Borges
Boettcher, Michael E.
Boulet, Gilles
Breinl, Korbinian
Brilly, Mitja
Brocca, Luca
Buytaert, Wouter
Castellarin, Attilio
Castelletti, Andrea
Chen, Xiaohong
Chen, Yangbo
Chen, Yuanfang
Chifflard, Peter
Claps, Pierluigi
Clark, Martyn P.
Collins, Adrian L.
Croke, Barry
Dathe, Annette
David, Paula C.
de Barros, Felipe P. J.
de Rooij, Gerrit
Di Baldassarre, Giuliano
Driscoll, Jessica M.
Duethmann, Doris
Dwivedi, Ravindra
Eris, Ebru
Farmer, William H.
Feiccabrino, James
Ferguson, Grant
Ferrari, Ennio
Ferraris, Stefano
Fersch, Benjamin
Finger, David
Foglia, Laura
Fowler, Keirnan
Gartsman, Boris
Gascoin, Simon
Gaume, Eric
Gelfan, Alexander
Geris, Josie
Gharari, Shervan
Gleeson, Tom
Glendell, Miriam
Bevacqua, Alena Gonzalez
Gonzalez-Dugo, Maria P.
Grimaldi, Salvatore
Gupta, A. B.
Guse, Bjoern
Han, Dawei
Hannah, David
Harpold, Adrian
Haun, Stefan
Heal, Kate
Helfricht, Kay
Herrnegger, Mathew
Hipsey, Matthew
Hlavacikova, Hana
Hohmann, Clara
Holko, Ladislav
Hopkinson, Christopher
Hrachowitz, Markus
Illangasekare, Tissa H.
Inam, Azhar
Innocente, Camyla
Istanbulluoglu, Erkan
Jarihani, Ben
Kalantari, Zahra
Kalvans, Andis
Khanal, Sonu
Khatami, Sina
Kiesel, Jens
Kirkby, Mike
Knoben, Wouter
Kochanek, Krzysztof
Kohnova, Silvia
Kolechkina, Alla
Krause, Stefan
Kreamer, David
Kreibich, Heidi
Kunstmann, Harald
Lange, Holger
Liberato, Margarida L. R.
Lindquist, Eric
Link, Timothy
Liu, Junguo
Loucks, Daniel Peter
Luce, Charles
Mahe, Gil
Makarieva, Olga
Malard, Julien
Mashtayeva, Shamshagul
Maskey, Shreedhar
Mas-Pla, Josep
Mavrova-Guirguinova, Maria
Mazzoleni, Maurizio
Mernild, Sebastian
Misstear, Bruce Dudley
Montanari, Alberto
Mueller-Thomy, Hannes
Nabizadeh, Alireza
Nardi, Fernando
Neale, Christopher
Nesterova, Nataliia
Nurtaev, Bakhram
Odongo, Vincent O.
Panda, Subhabrata
Pande, Saket
Pang, Zhonghe
Papacharalampous, Georgia
Perrin, Charles
Pfister, Laurent
Pimentel, Rafael
Polo, Maria J.
Post, David
Prieto, Cristina
Ramos, Maria-Helena
Renner, Maik
Reynolds, Jose Eduardo
Ridolfi, Elena
Rigon, Riccardo
Riva, Monica
Robertson, David E.
Rosso, Renzo
Roy, Tirthankar
Sa, Joao H. M.
Salvadori, Gianfausto
Sandells, Mel
Schaefli, Bettina
Schumann, Andreas
Scolobig, Anna
Seibert, Jan
Servat, Eric
Shafiei, Mojtaba
Sharma, Ashish
Sidibe, Moussa
Sidle, Roy C.
Skaugen, Thomas
Smith, Hugh
Spiessl, Sabine M.
Stein, Lina
Steinsland, Ingelin
Strasser, Ulrich
Su, Bob
Szolgay, Jan
Tarboton, David
Tauro, Flavia
Thirel, Guillaume
Tian, Fuqiang
Tong, Rui
Tussupova, Kamshat
Tyralis, Hristos
Uijlenhoet, Remko
van Beek, Rens
van der Ent, Ruud J.
van der Ploeg, Martine
Van Loon, Anne F.
van Meerveld, Ilja
van Nooijen, Ronald
van Oel, Pieter R.
Vidal, Jean-Philippe
von Freyberg, Jana
Vorogushyn, Sergiy
Wachniew, Przemyslaw
Wade, Andrew J.
Ward, Philip
Westerberg, Ida K.
White, Christopher
Wood, Eric F.
Woods, Ross
Xu, Zongxue
Yılmaz, Koray Kamil
Zhang, Yongqiang
This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through online media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focused on the process-based understanding of hydrological variability and causality at all space and time scales. Increased attention to environmental change drives a new emphasis on understanding how change propagates across interfaces within the hydrological system and across disciplinary boundaries. In particular, the expansion of the human footprint raises a new set of questions related to human interactions with nature and water cycle feedbacks in the context of complex water management problems. We hope that this reflection and synthesis of the 23 unsolved problems in hydrology will help guide research efforts for some years to come.


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Citation Formats
G. Bloeschl et al., “Twenty-three unsolved problems in hydrology (UPH) - a community perspective,” HYDROLOGICAL SCIENCES JOURNAL-JOURNAL DES SCIENCES HYDROLOGIQUES, pp. 1141–1158, 2019, Accessed: 00, 2021. [Online]. Available: