International Association Of Hydrological Sciences Research Articles

The International Commission on Continental Erosion (ICCE): a brief overview of its scientific focus and example outputs

Abstract. Erosion and sediment-related problems are well documented globally and continue to warrant further scientific investigation, as well as improved policies and management strategies to protect soil and water resources. The International Commission on Continental Erosion (ICCE) has long been a very active commission of the International Association of Hydrological Sciences (IAHS) focussing on progressing scientific understanding of erosion and sediment systems. This paper provides a brief overview of its main scientific foci, examples of previous contributions to scientific conferences and finally, concludes by paying tribute to two key former members of the international scientific community engaged with its remit.

Where should hydrology go? An early-career perspective on the next IAHS Scientific Decade: 2023–2032

ABSTRACT This paper shares an early-career perspective on potential themes for the upcoming International Association of Hydrological Sciences (IAHS) Scientific Decade (SD). This opinion paper synthesizes six discussion sessions in western Europe identifying three themes that all offer a different perspective on the hydrological threats the world faces and could serve to direct the broader hydrological community: “Tipping points and thresholds in hydrology,” “Intensification of the water cycle,” and “Water services under pressure.” Additionally, four trends were distinguished concerning the way in which hydrological research is conducted: big data, bridging science and practice, open science, and inter- and multidisciplinarity. These themes and trends will provide valuable input for future discussions on the theme for the next IAHS SD. We encourage other early-career scientists to voice their opinion by organizing their own discussion sessions and commenting on this paper to make this initiative grow from a regional initiative to a global movement.

Spatial distribution of groundwater recharge, based on regionalised soil moisture models in Wadi Natuf karst aquifers, Palestine

Abstract. While groundwater recharge is considered fundamental to hydrogeological insights and basin management and studies on its temporal variability are in great number, much less attention has been paid to its spatial distribution, by comparison. And in ungauged catchments it has rarely been quantified, especially on the catchment scale. For the first time, this study attempts such analysis, in a previously ungauged basin. Our work is based on the results of field data (as published in Messerschmid et al., 2020) of several soil moisture stations, which represent five geological formations of karst rock in Wadi Natuf, a semi-arid to sub-humid Mediterranean catchment in the occupied Palestinian West Bank. For that purpose, recharge was conceptualised as deep percolation from soil moisture under saturation excess conditions, which had been modelled parsimoniously and separately with different formation-specific recharge rates. For the regionalisation, inductive methods of empirical field measurements and observations were combined with deductive approaches of extrapolation, based on a new basin classification framework (BCF) for Wadi Natuf, thus following the recommendations for hydrological Prediction in Ungauged Basins (PUB), by the International Association of Hydrological Sciences (IAHS). Our results show an average annual recharge estimation in Wadi Natuf catchment (103 km2), ranging from 235 to 274 mm (24 to 28×106 m3) per year, equivalent to recharge coefficients (RCs) of 39 %–46 % of average annual precipitation (over a 7-year observation period but representative of long-term conditions as well). Formation-specific RC values, derived from empirical parsimonious soil moisture models, were regionalised and their spatial distribution was assessed and quantified on the catchment scale. Thus, for the first time, a fully distributed recharge model in a hitherto entirely ungauged (and karstic) aquifer basin was created that drew on empirical methods and direct approaches. This was done by a novel combination of existing methods and by creating a unified conceptual basin classification framework for different sets of physical basin features. This new regionalisation method is also applicable in many comparable sedimentary basins in the Mediterranean and worldwide.

Citizens AND HYdrology (CANDHY): conceptualizing a transdisciplinary framework for citizen science addressing hydrological challenges

ABSTRACT Widely available digital technologies are empowering citizens who are increasingly well informed and involved in numerous water, climate, and environmental challenges. Citizen science can serve many different purposes, from the “pleasure of doing science” to complementing observations, increasing scientific literacy, and supporting collaborative behaviour to solve specific water management problems. Still, procedures on how to incorporate citizens’ knowledge effectively to inform policy and decision-making are lagging behind. Moreover, general conceptual frameworks are unavailable, preventing the widespread uptake of citizen science approaches for more participatory cross-sectorial water governance. In this work, we identify the shared constituents, interfaces, and interlinkages between hydrological sciences and other academic and non-academic disciplines in addressing water issues. Our goal is to conceptualize a transdisciplinary framework for valuing citizen science and advancing the hydrological sciences. Joint efforts between hydrological, computer, and social sciences are envisaged for integrating human sensing and behavioural mechanisms into the framework. Expanding opportunities of online communities complement the fundamental value of on-site surveying and indigenous knowledge. This work is promoted by the Citizens AND HYdrology (CANDHY) Working Group established by the International Association of Hydrological Sciences (IAHS).

Regionalization of hydrological modeling for predicting streamflow in ungauged catchments: A comprehensive review

AbstractRunoff prediction in ungauged and scarcely gauged catchments is a key research field in surface water hydrology. There have been numerous studies before and since the launch of the predictions in ungauged basins (PUB) initiative by the International Association of Hydrological Sciences in 2003. This study critically reviews and assesses the decadal progress in the regionalization of hydrological modeling, which is the major tool for PUB, from 2000 to 2019. This paper found that the journal publications have noticeably increased in terms of PUB in the past 7 years, and research countries have been expanded dramatically since 2013. The regionalization methods are grouped into three categories including similarity‐based, regression‐based, and hydrological signature‐based. There are more detailed researches focusing on the interdisciplinary and profound improvement of each regionalization method. Namely, tremendous efforts have been made and lots of improvements have been carried out in the parameterization domain for the post‐PUB period. However, there is still plenty of room to improve the prediction capability in data‐sparse regions (e.g., further verification and proof of multi‐modeling adaptation and uncertainties description). This paper also discusses possible research directions in the future, including PUB in a changing environment and better utilization of multi‐source remote‐sensing information.This article is categorized under: Science of Water > Science of Water

Scientometric analysis of the activities of the International Commission for Continental Erosion (ICCE)

Abstract. The article is dedicated to the analysis of the International Commission of Continental Erosion (ICCE) of International Association of Hydrological Sciences (IAHS) activity since foundation in 1981. The empirical data is the collections of scientific articles, published in IAHS Red Books after symposiums and workshops, organized by the ICCE. 2460 authors published articles in Red Books, 81 % of them have publication in the one issue. The most active contributors (who have articles in 7 or more issues) compose a group of 39 scientists (1.6 % from the total number of authors). Researchers from 89 countries were published articles in the ICCE issues of Red Books. The activity of the ICCE can be described by a cyclic model of growth. It is shown that the ICCE scientific community is becoming progressively global.

\u2018New insight into statistical hydrology\u2019 preface to the special issue

Statistical methods are still the basic tool for investigating random, extreme events occurring in hydrosphere. On 21-22 September 2017, in Warsaw (Poland) the international workshop of the Statistical Hydrology (StaHy) 2017 took place under the auspices of the International Association of Hydrological Sciences. The authors of the presentations proposed to publish their research results in the Special Issue of the Acta Geophysica–‘New Insight into Statistical Hydrology’. Five papers were selected for publication, touching on the most crucial issues of statistical methodology in hydrology.

Measurements and Observations in the XXI century (MOXXI): innovation and multi-disciplinarity to sense the hydrological cycle

ABSTRACTTo promote the advancement of novel observation techniques that may lead to new sources of information to help better understand the hydrological cycle, the International Association of Hydrological Sciences (IAHS) established the Measurements and Observations in the XXI century (MOXXI) Working Group in July 2013. The group comprises a growing community of tech-enthusiastic hydrologists that design and develop their own sensing systems, adopt a multi-disciplinary perspective in tackling complex observations, often use low-cost equipment intended for other applications to build innovative sensors, or perform opportunistic measurements. This paper states the objectives of the group and reviews major advances carried out by MOXXI members toward the advancement of hydrological sciences. Challenges and opportunities are outlined to provide strategic guidance for advancement of measurement, and thus discovery.

Symposium of the International Commission on Continental Erosion of the International Association of Hydrological Sciences (ICCE IAHS)

Symposium of the International Commission on Continental Erosion of the International Association of Hydrological Sciences (ICCE IAHS)

Adaptation of water resources systems to changing society and environment: a statement by the International Association of Hydrological Sciences

ABSTRACTWe explore how to address the challenges of adaptation of water resources systems under changing conditions by supporting flexible, resilient and low-regret solutions, coupled with on-going monitoring and evaluation. This will require improved understanding of the linkages between biophysical and social aspects in order to better anticipate the possible future co-evolution of water systems and society. We also present a call to enhance the dialogue and foster the actions of governments, the international scientific community, research funding agencies and additional stakeholders in order to develop effective solutions to support water resources systems adaptation. Finally, we call the scientific community to a renewed and unified effort to deliver an innovative message to stakeholders. Water science is essential to resolve the water crisis, but the effectiveness of solutions depends, inter alia, on the capability of scientists to deliver a new, coherent and technical vision for the future development of water systems.EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR not assigned

The seventh facet of uncertainty: wrong assumptions, unknowns and surprises in the dynamics of human–water systems

ABSTRACTThe scientific literature has focused on uncertainty as randomness, while limited credit has been given to what we call here the “seventh facet of uncertainty”, i.e. lack of knowledge. This paper identifies three types of lack of understanding: (i) known unknowns, which are things we know we don’t know; (ii) unknown unknowns, which are things we don’t know we don’t know; and (iii) wrong assumptions, things we think we know, but we actually don’t know. Here we discuss each of these with reference to the study of the dynamics of human–water systems, which is one of the main topics of Panta Rhei, the current scientific decade of the International Association of Hydrological Sciences (IAHS), focusing on changes in hydrology and society. In the paper, we argue that interdisciplinary studies of socio-hydrological dynamics leading to a better understanding of human–water interactions can help in coping with wrong assumptions and known unknowns. Also, being aware of the existence of unknown unknowns, and their potential capability to generate surprises or black swans, suggests the need to complement top-down approaches, based on quantitative predictions of water-related hazards, with bottom-up approaches, based on societal vulnerabilities and possibilities of failure.Editor D. Koutsoyiannis; Associate editor S. Weijs

Panta Rhei 2013–2015: global perspectives on hydrology, society and change

ABSTRACTIn 2013, the International Association of Hydrological Sciences (IAHS) launched the hydrological decade 2013–2022 with the theme “Panta Rhei: Change in Hydrology and Society”. The decade recognizes the urgency of hydrological research to understand and predict the interactions of society and water, to support sustainable water resource use under changing climatic and environmental conditions. This paper reports on the first Panta Rhei biennium 2013–2015, providing a comprehensive resource that describes the scope and direction of Panta Rhei. We bring together the knowledge of all the Panta Rhei working groups, to summarize the most pressing research questions and how the hydrological community is progressing towards those goals. We draw out interconnections between different strands of research, and reflect on the need to take a global view on hydrology in the current era of human impacts and environmental change. Finally, we look back to the six driving science questions identified at the outset of Panta Rhei, to quantify progress towards those aims.Editor D. Koutsoyiannis; Associate editor not assigned

Joint Editorial: Fostering innovation and improving impact assessment for journal publications in hydrology

Editors of several journals in the field of hydrology met during the Assembly of the International Association of Hydrological Sciences - IAHS (within the Assembly of the International Union of Geodesy and Geophysics - IUGG) in Prague in June 2015. This event was a follow-up of a similar meeting held in July 2013 in Gothenburg (as reported by Bloschl et al. [2014]). These meetings enable the group of editors to review the current status of the journals and the publication process, and share thoughts on future strategies. Journals were represented in the 2015 meeting through their editors, as shown in the list of authors. The main points on fostering innovation and improving impact assessment in journal publications in hydrology are communicated in this joint editorial published in the above journals.

National Hydrological Associations—a new network to advance science, practice and capacity

Over the past 150 years National Hydrological Associations (NHAs) have been established in many countries. Hydrology has developed within many different contexts, as is reflected in the diverse nature of the NHAs that exist. Some NHAs have developed within a governmental context, while others owe their existence to the efforts by individual hydrologists. Their common objective is the promotion of the science and practice of hydrology, but their range of activities is very wide. On many occasions the International Association of Hydrological Sciences (IAHS) has collaborated with such Associations and has proposed that much could be gained if NHAs were to be in contact with each other, as well as with IAHS. From this arose the idea of establishing a Network of NHAs. An Agreement for the establishment of the Network was signed in Gothenburg in July 2013. Its Second General Assembly was held in Prague in July 2015.

Hydrology under change: an evaluation protocol to investigate how hydrological models deal with changing catchments

Testing hydrological models under changing conditions is essential to evaluate their ability to cope with changing catchments and their suitability for impact studies. With this perspective in mind, a workshop dedicated to this issue was held at the 2013 General Assembly of the International Association of Hydrological Sciences (IAHS) in Göteborg, Sweden, in July 2013, during which the results of a common testing experiment were presented. Prior to the workshop, the participants had been invited to test their own models on a common set of basins showing varying conditions specifically set up for the workshop. All these basins experienced changes, either in physical characteristics (e.g. changes in land cover) or climate conditions (e.g. gradual temperature increase). This article presents the motivations and organization of this experiment—that is—the testing (calibration and evaluation) protocol and the common framework of statistical procedures and graphical tools used to assess the model performances. The basins datasets are also briefly introduced (a detailed description is provided in the associated Supplementary material).

Hydrological drought explained

Drought is a complex natural hazard that impacts ecosystems and society in many ways. Many of these impacts are associated with hydrological drought (drought in rivers, lakes, and groundwater). It is, therefore, crucial to understand the development and recovery of hydrological drought. In this review an overview is given of the current state of scientific knowledge of definitions, processes, and quantification of hydrological drought. Special attention is given to the influence of climate and terrestrial properties (geology, land use) on hydrological drought characteristics and the role of storage. Furthermore, the current debate about the use and usefulness of different drought indicators is highlighted and recent advances in drought monitoring and prediction are mentioned. Research on projections of hydrological drought for the future is summarized. This review also briefly touches upon the link of hydrological drought characteristics with impacts and the issues related to drought management. Finally, four challenges for future research on hydrological drought are defined that relate international initiatives such as the Intergovernmental Panel on Climate Change (IPCC) and the ‘Panta Rhei’ decade of the International Association of Hydrological Sciences (IAHS).WIREs Water2015, 2:359–392. doi: 10.1002/wat2.1085This article is categorized under:Science of Water > Hydrological ProcessesScience of Water > Water and Environmental ChangeScience of Water > Water Extremes

Hydrological sciences and water security: An overview

Abstract. This paper provides an introduction to the concepts of water security including not only the risks to human wellbeing posed by floods and droughts, but also the threats of inadequate supply of water in both quantity and quality for food production, human health, energy and industrial production, and for the natural ecosystems on which life depends. The overall setting is one of constant change in all aspects of Earth systems. Hydrological systems (processes and regimes) are changing, resulting from varying and changing precipitation and energy inputs, changes in surface covers, mining of groundwater resources, and storage and diversions by dams and infrastructures. Changes in social, political and economic conditions include population and demographic shifts, political realignments, changes in financial systems and in trade patterns. There is an urgent need to address hydrological and social changes simultaneously and in combination rather than as separate entities, and thus the need to develop the approach of ‘socio-hydrology’. All aspects of water security, including the responses of both UNESCO and the International Association of Hydrological Sciences (IAHS) to the concepts of socio-hydrology, are examined in detailed papers within the volume titled Hydrological Sciences and Water Security: Past, Present and Future.

Panta Rhei, the new science decade of IAHS

Abstract. To address the water related problems that society is facing in this time and age, hydrologists can no longer consider the hydrological system as if there is no human influence. The human and water systems are closely intertwined and in this interaction patterns emerge that are the result of two co-evolving systems. The hydrology and the water resources form conditions under which societies develop, but as a result, and in turn, societies influence the functioning of the hydrological system. This calls for a new science that tries to understand these interactions with the objective to explore feasible futures and strategies to guide this co-evolution towards sustainable use of our natural resources. After the closure of the PUB decade on Prediction in Ungauged Basins, the International Association of Hydrological Sciences (IAHS) has taken up the challenge of trying to make fundamental contributions to this new science of integrated hydrological and societal processes under the title of "Panta Rhei", symbolising that everything changes in a perpetual dynamic interaction between people and water. This may be a big step in the science of hydrology, venturing well outside the comfortable boundaries of pristine hydrology, but the urgency of water issues around the globe forces us to do so, and in the process, hydrologists are likely to discover new paradigms, new modelling approaches, enhanced understanding of the human-water system, and hopefully new ways to steer our society towards a more sustainable future.

Prediction in ungauged estuaries: An integrated theory

AbstractMany estuaries in the world are ungauged. The International Association of Hydrological Sciences completed its science decade on Prediction in Ungauged Basins (PUB) in 2012 (Hrachowitz et al., ). Prediction on the basis of limited data is a challenge in hydrology, but not less so in estuaries, where data on fundamental processes are often lacking. In this paper, relatively simple, but science‐based, methods are presented that allow researchers, engineers, and water managers to obtain first‐order estimates of essential process parameters in estuaries, such as the estuary depth, the tidal amplitude, the tidal excursion, the phase lag, and the salt water intrusion, on the basis of readily obtainable information, such as topographical maps and tidal tables. These apparently simple relationships are assumed to result from the capacity of freely erodible water bodies to adjust themselves to external drivers and to dissipate the free energy from these drivers as efficiently as possible. Thus, it is assumed that these systems operate close to their thermodynamic limit, resulting in predictable patterns that can be described by relatively simple equations. Although still much has to be done to develop an overall physics‐based theory, this does not prevent us from making use of the empirical “laws” that we observe in alluvial estuaries.

Panta Rhei: an evolving scientific decade with a focus on water systems

Abstract. The paper presents an overview of the activity of Panta Rhei, the research decade launched in 2013 by the International Association of Hydrological Sciences. After one year of activity Panta Rhei has already stimulated several initiatives and a worldwide involvement of researchers in hydrology and sister disciplines. Providing an overview of the status of Panta Rhei is essential to further promote the participation of scientists and the completion of its structure, which is currently being shaped by receiving Research Theme and Working Group proposals from the community.