# FRIEND-Water A Global Perspective 2014-2022 Facts and Figures

Gil Mahe, Anil Mishra, Koen Verbist, Rita Marteleira, Gamal Abdo, Ernest Amoussou, Oula Amrouni, Kamagate Bamory, Trevor Daniell, Stephan Dietriech, et al.

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## To cite this version:

Gil Mahe, Anil Mishra, Koen Verbist, Rita Marteleira, Gamal Abdo, et al., FRIEND-Water A Global Perspective 2014-2022 Facts and Figures. UNESCO. pp.96, 2023. hal-04925233

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**FRIEND-Water**

A Global Perspective
2014-2022

**Facts and Figures**

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Published in 2023 by the United Nations Educational, Scientific and Cultural Organization
7, place de Fontenoy, 75352 Paris 07 SP, France

© UNESCO 2023

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This publication is available in Open Access under the Attribution-ShareAlike 3.0 IGO (CC-BY-SA 3.0 IGO) license (http://creativecommons.org/licenses/by-sa/3.0/igo/). By using the content of this publication, the users accept to be bound by the terms of use of the UNESCO Open Access Repository (http://www.unesco.org/open-access/terms-use-ccbysa-en).

The designations employed and the presentation of material throughout this publication do not imply the expression of any opinion whatsoever on the part of UNESCO concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.

The ideas and opinions expressed in this publication are those of the authors; they are not necessarily those of UNESCO and do not commit the Organization.

**Editors-in-Chief**

Gil Mahé, Anil Mishra and Koen Verbist

**Reviewer**

Rita Marteleira

**Contributors**

Gamal Abdo, Ernest Amoussou, Oula Amrouni, Kamagate Bamory, Trevor Daniell, Stephan Dietriech, Ahmed Eltayeb, Eduardo O. Planos Gutiérrez, Domiho Japhet Kodja, Henny A.J. van Lanen, Mohammed Meddi, Andrew Ogilvie, Didier Orange, Le Thi Phuong Quynh, Eric Servat, Raphael Tshimanga, Patrick Valimba, Santiago Yepez, Télesphore Brou Yao

**Acknowledgements**

Paulina Marcela Ramírez Quevedo, Barbara Kavuma, Hong Huynh, Renée Gift, Paulina Lopez

Cover photo: Iquitos, Pérou, April 2022 © Nowaczyk/Shutterstock.com
Printed in France
# Short Summary

## Achievements and Challenges of the FRIEND-Water Initiative from 2014-2022

The Flow Regimes from International Experimental and Network Data (FRIEND-Water) is a UNESCO Flagship Initiative within the Intergovernmental Hydrological Programme (IHP) which seeks to facilitate, promote and foster collaborations across borders between scientists (hydrologists and related disciplines) to conduct studies on shared river basins.

This report summarizes the FRIEND-Water programme activities developed in the period of 2014-2022, despite the challenges posed: securing financial support and the Covid-19 pandemic. FRIEND-Water remained active in many regions: from the Global FRIEND-Water conference in Montpellier in 2014, until the Beijing Global FRIEND-Water conference in 2018 and the arrival of the new regional coordinators in 2019, several meetings, workshops, training sessions and conferences were organized, welcoming participants from more than 150 countries.

FRIEND-Water has shown to be a very solid and active initiative. This was confirmed by the UNESCO-IHP evaluation in 2018, the resolution made by the UNESCO-IHP Intergovernmental Council on April 2022 on this Flagship initiative, and the multiple scheduled events for 2021 and 2022. The support that FRIEND-Water receives from Member States has been essential for its several achievements.

> Despite the Covid-19 pandemic imposed challenges, more than 150 countries participated in several FRIEND-Water activities

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unesco

*'Since wars begin in the minds of men and women it is in the minds of men and women that the defences of peace must be constructed'*
**FRIEND-Water**

A Global Perspective
2014-2022

**Facts and Figures**
# Foreword

Climate change impacts are mostly felt through the variability of the water cycle. However, the latest scientific publications highlight the unpredictability and exacerbation of such trends, which have been corroborated by extreme flooding, drought and tropical cyclones felt worldwide. Following the premise that "one cannot manage what one does not measure", monitoring water resources both surface and groundwater, is becoming of the utmost importance for decision-makers at local and national levels to make informed, resilience-building decisions.

In addition, out of the 17 Sustainable Development Goals, the water-related Goal (SDG 6) underpins and is interrelated with most of the other SDGs, as water is a critical input to meet many of the development and environmental targets. Science and technology can be powerful agents of change, placed at the heart of the 2030 Agenda. New scientific and technological research, as well as the adaptation of existing knowledge systems to local and regional contexts, are needed to streamline efforts and maximize synergies between sectors beyond the 2030 horizon.

Being the oldest Flagship initiative of UNESCO-IHP, the Flow Regimes from International Experimental and Network (FRIEND-Water) is a critical initiative to address these challenges, seeking to promote collaborative research agendas across borders on shared river and aquifer basins. Since its inception in 1985, FRIEND-Water has evolved significantly as a growing interest in common shared data and science has emerged. The UNESCO Flagship Initiatives Evaluation (2018) acknowledged this initiative's importance for achieving IHP's objectives.

UNESCO-IHP has just entered its ninth phase dedicated to developing "Science for a Water Secure World in a Changing Environment". IHP-IX (2022-2029) represents a methodological response towards transdisciplinarity to achieve a water-secure world in today's complex context. Its strategic plan addresses these ambitions through 5 priority areas (1. Scientific Research and Innovation; 2. Water Education in the Fourth

Industrial revolution including Sustainability; 3. Bridging the data-knowledge gap; 4. Integrated water management under conditions of global change; 5. Water governance based on science for mitigation, adaptation and resilience) and 34 outputs. IHP-IX programmatic content is designed with the objective to maximize the support to Member States in attaining SDG 6 and its related UN SDG 6 Global Accelerator Framework, UN Water Decade for Action (2018-2028) and other water-related goals and targets by strengthening scientific knowledge, data availability and enabling informed decision-making.

The report presents a compilation of the FRIEND-Water network achievements for the period of 2014-2022, marked by the Covid-19 pandemic that has paralysed the world, likewise affecting science development and ongoing research worldwide. Despite these challenges, FRIEND-Water remained active and demonstrated robustness and flexibility, adapting to the newly imposed travel restrictions by organizing virtual meetings. Upcoming activities will present an opportunity to think about how to respond to the triple planetary crisis, which includes climate change, pollution and biodiversity loss and how the FRIEND-Water programme can contribute to addressing these global challenges through new practices in science development in line with IHP-IX.

Abou Amani
Director, Water Sciences Division, UNESCO
# Table of Contents

Short Summary 1

Foreword 4

1 FRIEND-Water: a worldwide development through regional representations 6

1.1 Synergies of FRIEND-Water with international projects and programmes 8

1.2. Friend-Water Regional Coordinators (FWRC) 9

1.3 Friend-Water Intergroup Coordination Committee (FIGCC) 10

1.4 Financial aspects 11

2 FRIEND-water activities in the period of 2014-2022 12

3 UNESCO Flagship Initiatives Evaluation (2018) 14

4 FRIEND-Water strategic framework for the future 17

4.1 Regional perspectives for FRIEND 17

4.1.1 Europe (EURO) 17

4.1.2 Mediterranean (MED) 18

4.1.3 Latin America and the Caribbean (AMIGO) 19

4.1.4 South Africa (SA) 20

4.1.5 West and Central Africa (AOC) 22

4.1.6 Asian Pacific (AP) 23

4.1.7 Nile Basin 24

4.1.8 Congo Basin 25

4.2 Ecohydrology, a key interest for the future FRIEND-Water programme 27

4.3 Database development and support 29

5 Looking forward: FRIEND-Water in the context of IHP-IX, 2030 Agenda and Paris Agreement 30

6 References 32

7 Annexes

ANNEX 1: List of current FRIEND-Water Regional Coordinators 38

ANNEX 2: Summary of Beijing's 2018 Global FRIEND Conference 39

ANNEX 3: FRIEND-Water meetings 2014-2021 41

ANNEX 4: FRIEND-Water courses 2014-2021 46

ANNEX 5: FRIEND-Water publications 2014-2020 49
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© Scorpp/shutterstock.com

## 1 FRIEND-Water: a worldwide development through regional representations

The Flow Regimes from International Experimental and Network Data (FRIEND-Water) is a UNESCO Flagship Initiative within the Intergovernmental Hydrological Programme (IHP) which seeks to facilitate, promote and foster collaborations across borders between scientists (hydrologists and related disciplines) to conduct studies on shared river basins.

Since its inception in 1985 in Europe, making it the oldest programme of UNESCO-IHP, FRIEND-Water has evolved significantly. Among the scientific community, a growing interest in common shared data and scientific topics has emerged; leading to a geographical extension of FRIEND-Water to eight regional clusters around the world: SA FRIEND-Water (Southern Africa), CF FRIEND-Water (Congo), FRIEND-Water NILE, AMIGO FRIEND-Water (Latin America), EURO-FRIEND-Water, MEDFRIEND-Water (Mediterranean countries), AOC FRIEND-Water (West and Central Africa), and ASIAN PACIFIC FRIEND-Water (FRIEND-AP).

Aligned with IHP's agenda on water security, water-related Sustainable Development Goals (SDGs), Agenda 2030, the Paris Agreement and the Sendai Framework, FRIEND-Water Programme (FWP) acts as a catalyst promoting collective efforts to understand regional-wise hydrological processes

and their linkages at a global level. Within that purpose, FRIEND-Water articulates two main actions: i) stimulates research activities carried out by regional researchers in hydrology, related topics and shared databases and ii) promotes dialogue between scientists, local communities and policy makers. Every four years, FRIEND-Water holds an international conference in partnership with national universities, research institutes and the International Association of Hydrological Sciences (IAHS). In addition, FRIEND-Water regional groups organize international meetings, conferences, workshops, training sessions, scientific exchanges and field trips, while also sharing softwares and tools. Several communications are published in special issues of regular indexed journals and conference proceedings of IAHS.

Table 1 summarizes the countries participating in each regional group.
<table><caption>TABLE 1 • Countries participating in the Friend-Water programme</caption><thead><tr><th>Regional FRIEND-Water Group</th><th colspan="4">Participating countries</th></tr></thead><tbody><tr><td>European (EURO)<br>(31 countries, established<br>1985 and reorganised 2009)</td><td><ul><li>Albania</li><li>Austria</li><li>Belarus</li><li>Belgium</li><li>Bulgaria Czech</li><li>Republic</li><li>Denmark</li><li>Estonia</li></ul></td><td><ul><li>Finland</li><li>France</li><li>Germany</li><li>Hungary</li><li>Iceland</li><li>Ireland</li><li>Latvia</li><li>Lithuania</li></ul></td><td><ul><li>Luxembourg</li><li>Moldavia</li><li>Norway</li><li>Poland</li><li>Romania</li><li>Russia</li><li>Serbia</li><li>Slovakia</li></ul></td><td><ul><li>Slovenia</li><li>Sweden</li><li>Switzerland</li><li>The Netherlands</li><li>Turkey</li><li>Ukraine</li><li>United Kingdom</li></ul></td></tr><tr><td>Mediterranean (MED)<br>(18 countries, established<br>1991 and reorganised 2009)</td><td><ul><li>Algeria</li><li>Albania</li><li>Cyprus</li><li>Egypt</li><li>France</li></ul></td><td><ul><li>Greece</li><li>Israel</li><li>Italy</li><li>Jordan</li><li>Lebanon</li></ul></td><td><ul><li>Libya</li><li>Malta</li><li>Morocco</li><li>Slovenia</li></ul></td><td><ul><li>Spain</li><li>Syria</li><li>Tunisia</li><li>Turkey</li></ul></td></tr><tr><td>Latin American & Caribbean<br>(AMIGO) (46 countries,<br>established 1999)</td><td><ul><li>Anguilla</li><li>Antigua and<br>Barbuda Argentina</li><li>Aruba</li><li>Bahamas</li><li>Barbados</li><li>Bermuda</li><li>Bolivia</li><li>Brazil</li><li>British Virgin<br>Islands Cayman<br>Islands</li></ul></td><td><ul><li>Chile</li><li>Colombia</li><li>Costa Rica</li><li>Cuba</li><li>Dominica</li><li>Dominican<br>Republic</li><li>Ecuador</li><li>French Guiana</li><li>French West Indies</li><li>Grenada</li><li>Guyana</li><li>Haiti</li></ul></td><td><ul><li>Honduras</li><li>Jamaica</li><li>Mexico</li><li>Montserrat</li><li>Netherlands<br>Antilles</li><li>Panama</li><li>Paraguay</li><li>Peru</li><li>Puerto Rico</li><li>Saint Kitts and<br>Nevis Saint Lucia</li></ul></td><td><ul><li>St Vincent & The<br>Grenadines</li><li>Suriname</li><li>Trinidad and<br>Tobago</li><li>Turks and Caicos<br>Islands</li><li>US Virgin Islands</li><li>Uruguay</li><li>Venezuela</li></ul></td></tr><tr><td>Southern Africa (SA)<br>(13 countries, established<br>1991)</td><td><ul><li>Angola</li><li>Botswana</li><li>Lesotho</li><li>Rwanda</li></ul></td><td><ul><li>Malawi</li><li>Mauritius</li><li>Mozambique</li></ul></td><td><ul><li>Namibia</li><li>South Africa</li><li>Swaziland</li></ul></td><td><ul><li>Tanzania</li><li>Zambia</li><li>Zimbabwe</li></ul></td></tr><tr><td>West & Central Africa (AOC)<br>(18 countries, established<br>1992)</td><td><ul><li>Benin</li><li>Burkina Faso</li><li>Cameroon</li><li>Central Africa<br>Republic</li><li>Chad</li></ul></td><td><ul><li>Congo</li><li>Cote d'Ivoire</li><li>Gabon</li><li>Ghana</li><li>Guinea</li></ul></td><td><ul><li>Liberia</li><li>Mali</li><li>Mauritania</li><li>Niger</li></ul></td><td><ul><li>Nigeria</li><li>Senegal</li><li>Sierra Leone</li><li>Togo</li></ul></td></tr><tr><td>Asian Pacific (AP) (32<br>countries, established 1997),<br>including HKH countries<br>since 2018, (i.e. 42 countries)</td><td><ul><li>Australia</li><li>Cambodia</li><li>China</li><li>Cook Islands</li><li>Democratic Peoples<br>Republic of Korea</li><li>East Timor</li><li>Federated States of<br>Micronesia Fiji</li></ul></td><td><ul><li>Indonesia</li><li>Japan</li><li>Kiribati</li><li>Maldives</li><li>Mongolia</li><li>Myanmar</li><li>Nauru</li><li>New Caledonia</li></ul></td><td><ul><li>Pacific Islands:<br>American Samoa<br>Republic of Korea</li><li>Laos</li><li>Malaysia</li><li>New Zealand</li><li>Niue</li><li>Papua New Guinea</li></ul></td><td><ul><li>Philippines</li><li>Samoa</li><li>Solomon Islands</li><li>Thailand</li><li>Tonga</li><li>Tuvalu</li><li>Vanuatu</li><li>Vietnam</li></ul></td></tr><tr><td>Hindu-Kush Himalayas (HKH)<br>(11 countries, established<br>1996 and reorganised 2007)</td><td><ul><li>Afghanistan</li><li>Bangladesh</li><li>Bhutan</li></ul></td><td><ul><li>China India</li><li>Kazakhstan</li><li>Kyrgyzstan</li></ul></td><td><ul><li>Myanmar</li><li>Nepal</li><li>Pakistan</li></ul></td><td><ul><li>Tajikistan</li><li>Uzbekistan</li></ul></td></tr><tr><td>Nile (NF) (6 countries,<br>established 1996)</td><td><ul><li>Egypt</li><li>Ethiopia</li></ul></td><td><ul><li>Kenya</li><li>Sudan</li></ul></td><td><ul><li>Tanzania</li></ul></td><td><ul><li>Uganda</li></ul></td></tr><tr><td>Congo (CF) (9 countries,<br>established 2018)</td><td><ul><li>Angola</li><li>Burundi</li><li>Cameroon</li></ul></td><td><ul><li>Central African<br>Republic</li><li>Congo</li></ul></td><td><ul><li>Democratic Rep.<br>of Congo</li><li>Rwanda</li><li>Tanzania</li></ul></td><td><ul><li>Zambia</li></ul></td></tr></tbody></table>
The FRIEND-water Programme has a dedicated FWP Secretariat that coordinated the programme in close cooperation with UNESCO-IHP Secretariat. During the FRIEND-Water Intergroup Coordination Commitee (FIGCC) meeting held on 25 November 2020, the International Center for Interdisciplinary Research on Water Systems Dynamics (ICIReWaRD) in Montpellier, France, a Category II Centre under the auspices of UNESCO, has been endorsed to become the global secretariat for the FRIEND-water Programme.

## 1.1 Synergies of FRIEND-Water with international projects and programmes

FRIEND-Water regional groups develop applied research to meet local challenges. However, there are cross-cutting subjects to several regions (such as floods and low flows/drought, snow and glacier hydrology, erosion/sedimentation and water quality), which allow creating synergies among the different FRIEND-Water regions. Ecohydrology has been of increasing interest to the different regions. Its development within FRIEND-Water has been fostered by the Ecohydrology programme (EH) of UNESCO-IHP, which aims to launch common experimental sites, among other goals. A special session on Ecohydrology has been organized during the Global FRIEND conference (Beijing, November 2018) and further joint meetings are scheduled.

Along with the programme on Ecohydrology, UNESCO-IHP develops several initiatives from which FRIEND-Water could generate positive feedbacks and synergies: the International Flood Initiative (IFI), International Sediment Initiative (ISI), International Drought Initiative (IDI), World Large River Initiative (WLRI) and UNESCO's programme for Water and Development Information for Arid Lands - a Global Network (G-WADI). Hence, it is very important that FRIEND-Water takes advantage of the complementarities among different programmes, allowing maximizing synergies and minimizing duplication with other IHP initiatives.

Other ongoing research addresses groundwater, in particular shortage under dry environmental conditions. The Groundwater Drought Initiative (GDI) has been established across Europe.

Large-scale studies explored how groundwater pumping, which is vitally important for irrigation and associated food security, decreases streamflow globally, and estimated where and when environmentally critical stream flows will no longer be sustained. Furthermore, hydrological knowledge is increasingly used to study impacts of natural hazards on socio-economic and environmental variables – there is a special attention to the relationship between droughts and/or floods and people. Classical bottom-up approaches, which include vulnerability assessments are combined with top-down approaches to switch from reactive to pro-active risk management. In this context, the study of multi-hazards (coinciding and cascading) is a focal topic that aims at the development of Early Warning Systems (EWS), including understanding, identifying, monitoring and forecasting hazards.

Other studies deal with the processes of transfer and transformation of matter within the large global hydrological systems. With emphasis on rivers, lakes and reservoirs, several research initiatives are trying to understand the balance of sediments and their role in primary production, in particular in water quality. Different groups of FRIEND-Water rely on new remote sensing technologies to observe the spatial and temporal dynamics of these processes. A particular case is the use of satellite images as a tool to densify and extend in situ observations which were traditionally measured in hydrological stations. This new type of approach, applied at different scales, allows balances to be made, helping to understand the natural variability of systems, quantifying transfer processes and determining possible effects at the regional and global level, many of which are the result of anthropogenic activity and/or climate change. FRIEND-Water, therefore, supports addressing hydrology and human-nature interactions in the context of complex water management problems.

Other ongoing studies are using distributed climate data in hydrological models to assess the suitability of generated streamflow for rainfed agriculture, engineering designs of hydraulic and flood protection structures and ecological conservation. The emphasis is to understand the applicability of global climate data in real life challenges.
Global climate models data is becoming increas-
ingly available to fill gaps in observed climate
records and is very useful in large and/or ungauged
catchments.

During the eight phase of UNESCO-IHP
strategic framework, IHP-VIII (2018-2021), it was
recommended to all regional groups to promote
training sessions and workshops on the theme
of spatial hydrology, a research field that can
bring major future improvements in hydrological
sciences, closely related to the processing and
sharing of huge hydrological databases. It has been
also recommended to strengthen the dissemina-
tion and outreach activities of FRIEND-Water, with
the purpose of reaching a larger public, including
scholars and civil society, aligned with the orienta-
tions of the latest phase of UNESCO-IHP "Science for
a water secure world in a changing environment",
IHP-IX (2022-2029).

Flgahsip initiatives of UNESCO-IHP are reviewed by
the IHP Intergovernmental Council, which is also
in charge of the planning, definition of priorities,
and supervision of the execution of UNESCO-IHP.
After an evaluation of flagship Initiatives in 2018,
the IHP Council endorsed Resolution XXV-3
"Continuation of Flagship Initiatives during IHP-IX"
and decided that the FRIEND-Water programme
was recommended to continue given its good
performance during IHP-VIII. At the same time, the
Council requested all Flagship Initiatives to follow
the new Flagship Initiative Framework and to align
its strategy to the approved strategic framework of
IHP-IX.

## 1.2. Friend-Water Regional Coordinators (FWRC)

FRIEND-Water regional coordinators (FWRC)
are nominated and appointed by the FRIEND
Intergroup Coordination Committee (FIGCC) after
a selection of the applications. The positions are
effective for 4 years with possibility of an extension
for 4 more years, renewed only once. For each
region, the FWRC is assisted by a vice-coordinator,
nominated in agreement with the FRIEND-Water
direction and the FWRC, whose task is to assist and/
or replace the FWRC when necessary.

FWRC candidates must be a recognized scientist
in the region, with significant experience in
international collaborations, either in research
programmes or in international commissions or
institutions. The candidate must have a strong
institutional support from his/her institution as
the responsibilities require some dedicated staff
time and possible financial support (at least in
kind support for staff time and hosting events).
He/she must present a plan for the development
of activities in their regions within the 4 years
mandate, in collaboration with a team of Regional
Research Themes Coordinators (RRTC). Ideally,
the activities scheduled are associated with other
research activities and focus on regional priorities
and new scientific questions from a multidis-
ciplinary point of view. The activities should
also be aligned with the strategic action plan of
UNESCO-IHP ongoing phase.

The FWRCs main role is to leverage opportunities
to increase the scientific activities of hydrologists
in the region, taking into account their relevance
in regard of the regional research priorities. The
main activities to be organized by the FWRCs and
respective RRTCs in their regions include:

* International conferences, seminars and workshops;

* International training sessions and summer schools;

* Database sharing;

* Scientific exchanges for students, junior or senior scientists;

* Transferring knowledge and skills to operational organizations;

* Editing books or proceedings, special issues of peer-reviewed scientific journals;

* Contributing to Science Policy Briefs.

In addition, the FWRC must report to the
Coordination Committee, at UNESCO's request,
providing an annual report of activities, and
a 4-years report summarizing the activities
conducted within the region – the latter to be
submitted before the International FRIEND
conference and summarized in an online report
(previously called the 'Red Report') made publicly
available.
To ensure that all regions maintain an adequate pace of work, in the period between 2014 and 2022 FRIEND-Water has taken action revitalizing the programme through the creation of new statutes, the reorganization of regions or the nomination of regional coordinators. In 2016, new statutes have been written and approved by the FIGCC. FIGCC decided to: i) Launch the new CONGO-FRIEND program, which was already in preparation for some time; ii) Annex Hindu-Kush Himalaya (FRIEND-HKH) to Asia-Pacific (FRIEND-AP) and iii) Maintain FRIEND-EUROPE and MEDFRIEND, allowing a smooth transition.

Regarding the nomination of regional coordinators, a call for new coordinators was launched in 2017. Five regional coordinators were renewed in 2018: AMIGO, AOC, Nile, SA and AP. In particular, AOC received a large number of applications, showing the vitality of the FRIEND-Water programme in sub-Saharan Africa. All regions received applications except for FRIEND-HKH, triggering its annexation to FRIEND-AP. As far as FRIEND-EUROPE and MEDFRIEND are concerned, after a second call in 2019, the renewal of their coordinators has been examined and validated by the *ad hoc* FRIEND-Water committee, starting their activities by the end of 2020. As decided in the latest FIGCC meeting, held in Montpellier in the 1st of June of 2022, a new call will be launched in 2022 with the duration of 1 month. The list of current regional coordinators can be consulted in Annex I.

## 1.3 Friend-Water Intergroup Coordination Committee (FIGCC)

The FIGCC must support the regional activities, for instance by helping to connect with other international programmes or initiatives, either IHP-related (e.g. G-WADI, ISI, IDI, IFI, Ecohydrology, etc) or programmes from other academic institutions such as International Association of Hydrological Sciences (IAHS), International Association of Hydrogeologists (IAH), European Geosciences Union (EGU), American Geophysical Union (AGU) among others. It can also facilitate to better disseminate papers presented during the conferences into special issues of journals.

The FIGCC is composed by acknowledged specialists on water-related research topics, such as Ecohydrology or Socio-hydrology, who are proposed and appointed for 4 years, with a possible unique prolongation. Other areas of interest could also include socio-economic water-related issues, water-connected policy issues, and relationships with international associations or agencies like the International Basin Network, World Meteorological Organization, Global Runoff Data Centre, Global Freshwater Quality Database GEMStat, among others. Such networks could be useful for both data-sharing and dissemination for strategic future planning.

The FIGCC meets every two years, back-to-back with the 4-year FRIEND-Water conference and the mid-term evaluation. The FIGCC helps to organize the Global FRIEND-Water Conference, to nominate editors for the proceedings, and lead for the reporting. All the FWRCs must attend it to discuss the general strategy and future activities of the FWP. The discussions should also lead to the identification of future directions of the FRIEND-Water programme at global and regional levels, so that FWP could contribute to the generation of relevant and adapted scientific knowledge in addressing water-related challenges at global and regional levels.

In the Global FRIEND-Water Conference, the FWRCs elect a FIGCC Chair. The position of FIGCC Chair is effective for 4 years with possibility of a re-election for 4 more years. The main FIGCC chair tasks are as follows:

* Provide scientific leadership in accordance with the FIGCC recommendations;

* In coordination with FRIEND secretariat and IHP secretariat maintain scientific linkages with all regional coordinators and help them to develop their activities as recommended by the FRIEND Strategy;

* Provide scientific leadership and coordinate with regional coordinators in preparing their projects of events, finding external funding, and develop their networks;
* In coordination with FRIEND secretariat, promote the linkages between regions, in preparing or helping to prepare regional events involving several regions;

* Prepare the annual FIGCC meetings in coordination with the FRIEND Secretariat and IHP secretariat;

* Provide scientific leadership in coordination with the FRIEND secretariat and IHP Secretariat in the preparation of the Global FRIEND conference;

* Provide leadership to prepare the report of activities of the FRIEND-Water programme and its contribution to the IHP Programme (currently Phase IX), to be submitted to the IHP Intergovernmental Council every biennium;

* Maintain and develop the connexion with International Associations, like IAHS, to sponsor the FRIEND-Water events, and supervise the edition of the PIAHS volume;

* Maintain and develop the connexion with other UNESCO IHP programs;

* Encourage and support the edition of special issues of scientific journals, for instance following international events;

* Represent the FRIEND-Water programme in Scientific Committees of other UNESCO IHP programme and other research programmes and Institutions;

* Present the FRIEND-Water programme and activities in any relevant occasion, either invited or by its own initiative;

* Maintain contact with the UNESCO Water Family, Centers and UNESCO representations globally;

* Participate in scientific committees of International events, as FRIEND-Water representative.

The new Chair of the FRIEND-Water Inter Group Coordination Committee will be selected through a call that will take place between the final trimester of 2022 and the first semester of 2023. Therefore, the expectation is to have a new FIGCC chair at the 9th FRIEND-Water Global Conference 2023 in Dakar, Senegal.

This selection process for the FIGCC chair is expected to be modified at the upcoming conference, as the statutes, composition and role of the FIGCC will be modified, together with the process of nomination of the Chair of the Committee to be aligned with the new Flagship Initiative Framework. Furthermore, the call for a FIGCC chair will be accompanied of the FRIEND-Water Programme Call for Regional Coordinators, which will be selected also throughout the first half of 2023.

## 1.4 Financial aspects

The FRIEND secretariat will coordinate the implementation of FRIEND activities in coordination with regional coordinators and develop fund raising programmes with UNESCO, according the rules and procedures.

The FWRC are strongly encouraged to raise additional funding to support activities of the programme within the region. These funds can be sourced from research programs, national or international funding agencies, or any other opportunities. Cooperation with other UNESCO programs or initiatives is equally encouraged.
<figure><img src="image_7.png" /></figure>

©PradeepGaurs/shutterstock.com

## 2 FRIEND-water activities in the period of 2014-2022

During the period covered by the present report, two main issues have challenged the implementation of FRIEND-water related activities: to secure FWP financial support and the difficulties posed by the Covid-19 pandemic. To address the financial challenges, there has been an effort to develop synergies with other IHP initiatives such as Ecohydrology, G-WADI, ISI, WLRI, IDI and some regional groups.

Despite the afore-mentioned obstacles. FRIEND-Water has been active in many regions: from the Global FRIEND-Water conference in Montpellier in 2014, until the Beijing Global FRIEND-Water conference in 2018 (described in Annex 2), and the arrival of the new regional coordinators in 2019, several meetings, workshops, training sessions and conferences were organized over all regions, welcoming participants from more than

150 countries. FRIEND-Water has shown to be a very solid and active initiative. This was confirmed by UNESCO-IHP evaluation in 2018, described in the next section, the resolution made by the UNESCO-IHP Intergovernmental Council on April 2022 on this Flagship initiative, and the multiple scheduled events for 2021 and 2022. The support that FRIEND-Water receives from Member States has been essential for its several achievements.
The detailed list of meetings conducted in the reporting period of 2014-2021 by the various FWRCs can be consulted in Annex 3, the developed courses in Annex 4 and the list of publications in Annex 5.

From 2020, the Covid-19 pandemic prevented almost all scheduled regional events from taking place, and some events were converted into online meetings, such as the EURO FRIEND-Water project groups held as an online meeting during the Assembly of the European Geophysical Union (EGU2020: Sharing Geosciences Online). Some events overlapped with other events like the IAHS International conference in Montpellier which was held between 28th June and 2nd July 2022, with the FRIEND community being supported by the Category II UNESCO Research Center of Montpellier

at the "Maison des Sciences de l'Eau". FRIEND-Water was also present at the World Water Forum held in Dakar in 22nd to 26th of March 2022, after being postponed one year.

The upcoming Global FRIEND-Water conference, to be held in Dakar, Senegal, entitled "Addressing unsolved problems in hydrology for a Water World in a changing environment", will be a good opportunity to reflect on the evolution of the programme, under the perspective of keeping its focus on major development priorities and scientific key questions of all regions. This gathering will also be an occasion to think about how to respond to planetary contingencies like Covid-19 and the reduction of carbon footprint by integrating new practices, for example the organization of online meetings.
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©VarnaK/shutterstock.com

## 3 UNESCO Flagship Initiatives Evaluation (2018)

FRIEND-Water was assessed in 2018, on the basis of its reported activities. During the evaluated period, several regional programs (at least four) were not active, triggering several actions to cope with the experienced difficulties. Among them, the following actions were developed: (i) the renewal of the FRIEND-Water framework, rules and objectives, leading to the establishment of clear written rules to be applied by regional coordinations; and (ii) the review of applications and selection of regional coordinators by an ad-hoc committee. The main outcome of those measures was the renewal of 6 regional coordinations in 2018, four of them officialized during the Global FRIEND-Water conference carried out in Beijing in November 2018. The remaining two were officialized during the 4th International Conference of the Great Rivers of Africa, held in Cotonou, Benin, on 13th-20th of November 2021.

The assessment focused on the activities developed during UNESCO's Medium-Term Strategy (2014-2021), in the light of the 8th phase of UNESCO-IHP, "Water Security: Responses to Local, Regional and Global Challenges".

The evaluation focused, particularly, in the following criteria:

* Institutional and organisational setting of the Flagship initiatives (FIs), particularly their configuration within UNESCO-IHP;

* Relevance of IHP Flagship activities;

* Efficiency of IHP Flagship activities;

* Effectiveness of IHP Flagship activities;

* Financial situation of the Flagships and its effect on their performance;
Developed methodology, dissemination approach, and the quality and effects of the products delivered by the Flagship initiatives in terms of academic and policy influence and use; Flagship performance in terms of addressing UNESCO corporate priorities, gender equality and priority Africa.

Table 2 summarizes the scores obtained for UNESCO FIs. FRIEND-Water obtained a relevance score of 1.6, above the average of 1.3 for all FIs, meaning that this initiative has significant relevance within the IHP activities. The visibility score obtained (1.7, against an average score of 1.3) should also be highlighted.

<table><caption>TABLE 2 • Overview of the assessment of individual FIs from the IHP Flagship Evaluation Report (2018)</caption><thead><tr><td>Card findings criteria</td><td>Relevance</td><td>Perceived added value</td><td>Visibility</td><td>Governance and management</td><td>Inputs</td><td>Total</td></tr></thead><tbody><tr><td>FRIEND</td><td>1.6</td><td>1.3</td><td>1.7</td><td>1.3</td><td>0.8</td><td>1.3</td></tr><tr><td>GRAPHIC</td><td>1.4</td><td>1.0</td><td>1.5</td><td>1.3</td><td>0.6</td><td>1.2</td></tr><tr><td>G-WADI</td><td>1.9</td><td>1.8</td><td>1.8</td><td>1.8</td><td>1.2</td><td>1.7</td></tr><tr><td>HELP</td><td>1.6</td><td>0.8</td><td>1.5</td><td>0.5</td><td>0.8</td><td>1.1</td></tr><tr><td>IDI</td><td>1.6</td><td>1.0</td><td>0.5</td><td>0.8</td><td>0.8</td><td>1.0</td></tr><tr><td>IFI</td><td>1.3</td><td>1.8</td><td>1.5</td><td>1.8</td><td>1.0</td><td>1.5</td></tr><tr><td>IIWQ</td><td>2.0</td><td>1.3</td><td>1.0</td><td>1.7</td><td>1.6</td><td>1.6</td></tr><tr><td>ISARM</td><td>1.7</td><td>1.8</td><td>1.2</td><td>1.3</td><td>1.2</td><td>1.4</td></tr><tr><td>ISI</td><td>1.1</td><td>1.0</td><td>1.5</td><td>1.7</td><td>1.0</td><td>1.3</td></tr><tr><td>IWRM</td><td>1.4</td><td>1.8</td><td>1.0</td><td>0.3</td><td>0.8</td><td>1.0</td></tr><tr><td>JIIHP</td><td>0.6</td><td>0.0</td><td>0.2</td><td>0.0</td><td>0.0</td><td>0.2</td></tr><tr><td>MAR</td><td>1.0</td><td>1.0</td><td>0.8</td><td>0.7</td><td>0.6</td><td>0.8</td></tr><tr><td>PCCP</td><td>1.3</td><td>1.8</td><td>1.0</td><td>0.2</td><td>1.0</td><td>1.0</td></tr><tr><td>UWMP</td><td>0.4</td><td>0.8</td><td>0.3</td><td>0.3</td><td>0.4</td><td>0.4</td></tr><tr><td>WHYMAP</td><td>1.3</td><td>1.8</td><td>1.5</td><td>1.0</td><td>0.4</td><td>1.2</td></tr><tr><td>Average</td><td>1.3</td><td>1.2</td><td>1.1</td><td>1.0</td><td>0.8</td><td></td></tr></tbody></table>
The main outcomes and recommended actions, particular for FRIEND-Water, extracted from the IHP
Flagship Evaluation Report evaluation are listed below:

*   **Effectiveness/achievement of objectives:**
    All FIs have issued publications (i.e. scientific articles, implementation reports based on case studies, training manuals, etc.) and almost all of the FI have actively participated in conferences, especially in presentations or side event workshops. However, some FIs, including FRIEND, have reported fewer than 13 activities in a 5-year period.

✓ **ACTION 1**

The Assessment Report recommends FRIEND-Water to organize more events. This has been anticipated by the regional and general coordinators, who increased the number of activities, as shown on this report.

* **Visibility:** Nine FI have independent websites aiming at a reinforced visibility. The six others have an entry on the IHP or other partners' websites.

✓ **ACTION 2**

The webpage of FRIEND-Water needs to be updated in order to keep the visibility of the programme. This task has been postponed several times.

✓ **ACTION 3**

FRIEND-Water logo should be updated.
This could be subject to a call between
the regional programs.

✓ **ACTION 4**

Keep enlarging the FRIEND-Water
community.

The online survey undertaken confirmed that FRIEND-Water is the most well-known FI initiative from UNESCO-IHP (67% of the respondents agreed). However, a quarter of the respondents were not actively engaged in FRIEND-Water activities. Documents and activities dedicated to a large audience should be produced in order to increase the quality of the information that FRIEND-Water is sharing with national representatives. That is to say, national representatives in all countries where FRIEND-Water is active should be properly informed of the activities of the programme, and it should be encouraged the preparation of an annual synthesis.
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©lavizzara/shutterstock.com

# 4 FRIEND-Water strategic framework for the future

## 4.1 Regional perspectives for FRIEND

### 4.1.1 Europe (EURO)

FRIEND-EURO network has identified closely inter-related key issues and challenges to large-scale hydrology, crucial to improve the prediction of hydrological systems (surface/sub-surface) on large spatial and time scales (i.e. continental – multidecadal) under changing environmental conditions (Massei et al. 2018; Kingston et al., 2020). Large-scale hydrology depends on interactions across the ocean-atmosphere-vegetation/soil/aquifer system. Detection of climate indices and large-scale patterns directly from hydrological data (Renard & Thyer, 2019) is required. In addition, characterizing non-stationarity and time-scale

dependence of large-scale relationships also appears fundamental (Dieppois et al., 2013). Other remaining challenges to be studied are how climate system models are capable of representing large-scale relationships at different temporal scales, or how to assess whether model performance in simulating hydroclimatic variables results from realistic large-scale climate processes, or from other compensating biases (Dieppois et al., 2019). Improved knowledge on large-scale relationships would also lead to more skilful hydrological forecasts (Lavers et al., 2017).

As catchment characteristics play a dominant role in filtering out climate variability on river flow, including hydrological extremes (Van Lanen et al., 2013), efforts need to focus on improving rep-
presentation of key hydrological processes on the large scale, very often oversimplified in large-scale models. For instance, lateral re-distribution by hillslope processes, landscape (Laizé & Hannah, 2010) or subsurface heterogeneities (Hartmann et al., 2017), or the role of groundwater on large-scale hydrological response (Sidibe et al., 2019) needs to be accounted for. Over the last decade, substantial progress has been made on the detection and projections of hydrological extremes, including drought (e.g. Stahl et al., 2012; Prudhomme et al., 2014). Emerging topics have been identified, such as flash droughts, multi-year droughts (where these were not reported before), cold-climates' droughts, and anthropogenically-enhanced droughts.

Another major challenge addressed by FRIEND-EURO network is the attribution of the causes and processes leading to low flow (events), streamflow droughts, and intermittent flow. This needs improved knowledge on how weather anomalies eventually end up as hydrological drought (groundwater, streamflow), i.e., how climate and catchment controls, and human drivers affect drought development and termination (Van Loon et al., 2016). Groundwater, as an important catchment control, requires more attention (Stoelzle et al., 2014). A step forward is the pan-European Groundwater Drought Initiative (GDI)<fnref n="1" /> recently established. Furthermore, attribution calls for further development of hydrological models that dynamically consider changing environmental conditions implying focus on more process-based rather than calibration-based modelling approaches.

Europe-focused EWS, including monitoring and forecasting, will be further developed to mitigate and adapt to hydrological extremes and to enable rapid pro-active risk-management rather than a reactive approach. In this context, a critical appraisal of indices and indicators will be developed at the European scale. Hydrological knowledge is increasingly used to study impacts of drought on socio-economic and environmental conditions (Stahl et al., 2016; Blauhut et al.,

2015; Sutanto et al., 2019a). Classical bottom-up approaches, which use hazard, exposure and vulnerability as a basis, are combined with top-down approaches to change from reactive to pro-active risk management. In this context, study of multi-hazards (coinciding and cascading) is becoming a focal area (Sutanto et al., 2019b) in the further development of EWS.

Transnational hydroclimatic data are fundamental to investigate hydrological extremes and large-scale variation in hydrology. Flow data from European rivers will be regularly updated, as part of the further development of information systems as the Global Runoff Data Centre (GRDC) and other relevant data centres, and observational networks of the Global Terrestrial Network for Hydrology (GTN-H)<fnref n="2" />. Hydrometeorological services will be encouraged to provide these data. Large-scale hydrological data rescue (Le Gros et al., 2015) needs continuation, as well as the reconstruction of long-term, high-resolution climate datasets (Devers, 2020), and use of remote sensing products (e.g. GRACE). Compatibility between, or merging of, national-scale datasets (Caillouet et al., 2019) is planned to be further investigated to contribute to large-scale databases.

### 4.1.2 Mediterranean (MED)

The Mediterranean basin is characterized by limited and unevenly distributed water resources and a considerable development of anthropogenic activities. Hydro-climatic projections predict a decrease in average annual rainfall and runoff in this region of the world. Moreover, water demands have doubled since the 1950s and are expected to increase with the expansion of irrigated areas and urban areas. For the Mediterranean basin, according to climate projections, the temperature is projected to increase by 2 to 4°C and rainfall is projected to decrease by 4 to 30% by 2050 (Tramblay & Somot, 2018). This decrease in precipitation is projected to cause a decrease in flow for all four seasons. As a result of these climate changes, extreme peak flows are expected to increase dramatically. Hydrological

<footnote n="1">1 https://www.bgs.ac.uk/research/groundwater/waterResources/groundwaterDroughtInitiative/home.html</footnote>

<footnote n="2">2 GTN-H is a federation of global water data centres, inter alia the GRDC and GEMS/Water Data Centre and operates under the auspices of WMO and the Global Climate Observing System GCOS. www.gtn-h.info</footnote>
<figure><img src="image_10.png" /></figure>

©Wirestock Creators/shutterstock.com

droughts will worsen in summer, mainly in the Mediterranean region. The most extreme events are expected to occur in summer, with extreme droughts affecting the Mediterranean region and Mediterranean countries expected to face increasing water shortages.

Climate projections show a decrease in groundwater resources in the Mediterranean basin (Dubois et al, 2018). Overexploitation of groundwater in Mediterranean countries will lead to alarming levels of groundwater and increased pumping costs. Also, soil water stress conditions will drastically reduce agricultural production yields. Water consumption is already higher than water availability and is expected to be critical for global warming. In the countries on the southern shore of the Mediterranean and Spain, the situation of water resources will become more unsustainable in the future, which will have a negative impact on the availability of water resources to ensure sustainable development in these countries.

Thus the major research topics for FRIEND MED to deal with in priority in the Mediterranean area are:

* Extreme events or hydrological extremes and water-related disasters (Tramblay & Somot, 2018; Hadour et al., 2020);

* Erosion and transport of solids (Hallouz et al., 2018; Kotti et al., 2018);

* Integrated Water Resources Management (Marignani et al., 2017; Khater et al., 2019);

* Groundwater and global changes (Dubois et al., 2018; Erostate et al., 2020);

* Ecohydrology (Amrouni et al., 2019; Ben Moussa et al., 2019);

* Water in agriculture (Venot et al., 2017; Kuper et al., 2019; Reca-Cardena and Lopez-Luque, 2018).

Transversal topics will be of high importance, for instance water in the cities, education to water questions, participatory science, transition toward a more ecological approach of the water cycle and use. These will be developed through improved connections with all the sectors of society, and the development of new tools to communicate and disseminate knowledge, mainly web-based. A

significant challenge is to improve the co-development of research projects between countries of the Mediterranean and SubSaharan countries, and the Water Family of UNESCO is well positioned to support this.

### 4.1.3 Latin America and the Caribbean (AMIGO)

In the AMIGO region, the main challenge will be to implement a standard framework for assessing the conditions and evolution of rivers, considering hydrogeomorphological and ecological properties, which should be a priority for all future river management works. Recently, FWRC-AMIGO started to apply the River Styles framework to carry out hydrogeomorphological studies with an approach adapted to the local reality, focusing on the development of protocols and procedures (many of them using automated GIS/RS techniques) to assess the condition of rivers in South America and the Caribbean (Gallay et al., 2019). This would allow prioritizing rivers in terms of their conserva-
tion and restoration, as well as orienting sustainable management strategies, where the hydrogeomorphological factor is often incorporated in a limited way in engineering projects developed along the riverbanks (Yepez et al., 2017, 2018; Nardini et al., 2020). This approach must necessarily take into account, in a comprehensive manner, the different morphologies and varieties of rivers and also the particular nature of human disturbances (e.g. water diversions, reservoirs, gravel mining, urban sprawl, forestry activities, among others) and their distribution across regions.

The South American region has a strong vulnerability to climate change which affects not only rainfall regimes and temperature extremes, but also water resources systems. Many countries experiment a serious concern with glacier retreat from the last decades caused by a regional warming (Pabón-Caicedo et al. 2020). In general, Andean mountain catchments are also being affected by anthropogenic interventions, affecting water resources availability and water security (Laqui et al., 2018). In the Andean context, some hydrological processes are still unknown and misunderstood because of data scarcity (Ochoa-Tocachi et al., 2016), increasing the gap between decision-makers and development organizations. Besides, this alteration of the hydrological cycle is exacerbated by large scale climatic phenomena, as El Niño, worsening droughts or floods, and being more remarkable on both sides of the Andes, over the Pacific coast (Rau et al., 2018, 2019) and Amazonian regions (Marengo et al., 2016). Therefore, researchers are expected to provide reliable databases, scientific evidence and reinforced communication to improve water management practices and adaptation policies.

The Andes of South America and their surrounding basins are regions sensitive to climate change and tectonic events. Feedback between climate, tectonics and anthropogenic activities has a profound impact on the current landscape. Additionally, such processes have a significant impact on the biodiversity of species. AMIGO investigations use thermochronology and quantitative geomorphology techniques to model the landscape evolution and analyze the influence of these interactions on biodiversity. A combined effect of increased tectonic, climatic and anthropogenic

activities produces an increase in the sedimentation rates of rivers (Bermudez et al., 2019). Through numerical modeling, thermochronology and cosmogenic nuclides, it is possible to estimate long-term erosion rates and compare them with short term (or current) erosion rates, in order to discriminate the events that generate these increases (Carretier et al., 2018, Laraque et al., 2019).

Land-use changes lead to disturbances on weathering processes and nutrient cycles. Chemical weathering of continental rocks plays a central role in regulating the carbon cycle and the Earth's climate, as well as in the supplying of essential nutrients, such as N, P and trace metals for ecosystems. However, man-induced changes on land-use and hydrological features associated with natural resources exploitation, water extraction, damming and urbanization can alter water-rock interaction times, flow regimes, sediment transport (Araujo et al., 2017a, 2017b), which in turn, affect natural weathering regime and elemental biogeochemical cycles.

Human activity can also impact weathering via acid rain. Burning of fossil fuels releases nitrogen and sulfur compounds that later form nitric and sulfuric acids in rainwater. These are stronger acids than carbonic acid and they accelerate rock dissolution and negatively impact upon ecosystems. Oriented research from AMIGO aims to understand how climate change and anthropic actions can modify weathering processes at local and global magnitudes, at short and large scale-times, and impact aquatic ecosystems (Moquet et al., 2018).

### 4.1.4 South Africa (SA)

Monitoring of water bodies and floods by remote sensing is an increasingly important tool for hydrological studies. In the semi-arid rural areas of southern Africa (Mozambique and Tanzania) where the availability of water is a major issue for agriculture, the monitoring of surface water is extremely important (Andre et al., 2016; Mzava et al., 2019), particularly in ungauged watersheds. In addition, large cities, due to the weakness of water facilities, are particularly vulnerable to large-scale floods. Radar images are particularly well suited
to the seasonal observation of water surfaces in
tropical environments because the signal is freed
from cloudiness, which on the contrary constitutes
a major limitation of the use of optical images in
these environments. In addition, radar images are
very robust for detecting water surfaces (source,
etc.) where the signal backscattering is often very
low (almost zero) – on a radar image, the pixel-wa-
ters are those whose values are less than 0.05. The
possibilities offered by the European Space Agency
(Copernicus) thanks to its Sentinel 1 sensors make
it possible to have at least one image per month. A
Sentinel 1 radar monthly time series of images can
thus be created.

A good example of the management of hydro
agricultural resources in ungauged watersheds is
the case of the Kilombero watershed in Tanzania
(Johansson and Abdi, 2020). The Kilombero
watershed is a territory which potential in terms of
water and agricultural resources makes it a national
issue. Indeed, the Tanzanian government wants
to make these vast flood plains the granary of
Tanzania through an agricultural irrigation project.
At the same time, the Tanzanian government plans
to build a large hydroelectric dam, downstream

from the Kilombero watershed, which will
mobilize almost 66% of the water resources in
the watershed. Conflicts in the management of
water in this watershed could therefore arise, in
terms of competing for access to water between
these two projects of national importance.
Consideration should be given so that agricul-
tural production in the plain upstream also allows
optimal production of hydroelectricity downstream
from the watershed. In addition, to better manage
water resources, it is important to have a good
hydro-environmental and socio-economic
database. However, since the 1980s, no hydro-en-
vironmental and socio-economic measures have
been taken on this 35,000 km² watershed. The
first step will be to create a database (of hydro-
logical, climatic, land use, agricultural, socio-de-
mographic and touristic data) in order to better
understand the functioning of this territory, which
constitutes a national economic issue. In a second
step, FRIEND SA network will model the environ-
mental dynamics from the database thus created.
From an operational perspective, the database will
assist in the management of water resources in the
Kilombero watershed.

A second research direction from FRIEND SA
regional network which is of major importance
is the impact of climate variability and human
pressures on surface conditions. A follow-up of
the relationships between climatic variability and
vegetation must be first analyzed to understand
the natural dynamics of the landscape (Brou et
al., 2018; Brou 2019). This study is based on the
assumption of an increasing vulnerability of forest
ecosystems due to changes in the climate regime
recorded during the last thirty years.

To conduct this study, it is important to update the
knowledge of climate parameters, in particular the
amount of rain and its distribution throughout the
year. Equally important is the study of the trend and
frequency of climate data for the longest series of
observations available on the watershed. The study
of the sensitivity of vegetation to climatic variations
is carried out by means of a rain/NDVI co-variation
analysis. Several parameters will make it possible
to follow the interannual seasonal variability of the
vegetation: the start and end dates of vegetative
phases, the duration, the amplitude, the maximum

<figure><img src="image_11.png" /></figure>
<figure><img src="image_12.png" /></figure>

©Piyaset/shutterstock.com

of the vegetative season (Boussougou et al., 2017). To better understand local dynamics, Sentinel 2 images should be used. The comparison of images from different time periods will allow to assess, for each site, the levels of transformation of landscapes in relation to the degree of soil degradation.

The use of spatial data represents an important topic to strengthen the capacities of students in the monitoring and management of water resources at better spatio-temporal resolutions. In the context of global environmental changes, this training in geomatics is intended, ultimately, to strengthen the capacities of master and doctorate students in hydrology and geography in the field of water resources monitoring through the use of spatial data. This geomatics training is part of a favorable regional and international context marked by the availability of a large quantity of Sentinel data, Landsat satellite images in particular. In addition, the development of GPS makes it possible to collect terrain data with more precision. The objective is to allow users in environmental sciences, environmental managers or developers, to acquire the conceptual bases, methods of use and processing of remote sensing data. Applications in the field of water resources and coastal zones must be developed.

### 4.1.5 West and Central Africa (AOC)

In West and Central Africa, as in other regions of the world, FRIEND AOC supported studies have shown a growing risk of extreme events (excess rain and temperature, lack or scarcity of rain, etc.) with the advent of global warming, which is not without consequences for the capacities of production systems and water resources (Sidibe et al., 2018, 2020; Amoussou et al., 2020). We are witnessing the destruction of natural and human ecosystems and the loss of biological diversity by overflowing waters (flooding), very marked drying up of river beds and anthropogenic pressures. Changes in precipitation and temperature, as well as non-linear effects on humidity, evapotranspiration and soil, affect the quantity and quality of water resources, agriculture, fishing and livestock (Amoussou, 2020) and, therefore, the lives of the local population.

This climate change/variability coupled with demographic change and land degradation affects the hydrological balance and the frequency of extreme events and, therefore, the water levels in lakes (Zare et al., 2017), the hydraulicity downstream of the structures, resource uses in the developed sites, the dams, the safety of river water and gender inequalities in water management. To this end, it is important to develop studies on hydrological standards, intensity, duration and frequency (IDF) of storms, cold or heat waves on the one hand, and also the extent of regions affected by drought and unexpected floods, with unevenly distributed consequences for many regions of the world, particularly in developing countries (Parkes et al., 2019), and especially in Sahel (Descroix et al., 2018).

In order to overcome these hydrological catastrophic events, the Friend AOC network, with the support of the Research Institute for Development (IRD) has written and submitted a GDRI project entitled: "Hydrological Standards in West Africa and Power station for a better design of hydraulic structures".

The quality of hydrological networks has been decreasing continuously for decades in the region, despite the significant support from interna-
tional organizations. Thus, spatial hydrology
development and use are of utmost importance
in the region, and the first studies published
some years ago are very encouraging (Bogning
et al., 2020). This must be associated with a
significant increase of data sharing within large
communities of researchers (Dieulin et al., 2019).
At last, the economy of water uses becomes a
new dramatic challenge in these reputed dry and
waterpoor regions. It implies more pluridisicipli-
nary exchanges between hydrologists of surface
water and hydrogeologists, ecophysiologists and
soil scientists.

In addition, in the lagoon system of the coastal
regions the alternation of high and low water
generates a predominance of sea currents with
a strong sediment transit, or, sometimes, a pre-
dominance of the river current with addition
and deposition of sediments on the shore. The
mechanism of flood transport of sediments occurs
from upstream to downstream with the deposit
of fine particles at the entrance of floodplains. In
addition, in periods of high water, the river current
which feeds the lagoon systems increases and
exceeds in force the coastal or lagoon current, and
there is an increase in the solid loads and deposit
of coarse sands due to the weakening of the
current. For this reason, there is an elevation of the
river bed on one side and the digging of the other
side, related to the reinforcement of the current.
All of this creates disturbances with the rising
tide, causing flocculation and rapid deposition of
sediment in the lagoon system, which causes the
decline in the fishery productivity of water bodies.

The socio-economic and ecological importance
of the coastal zones of West and Central Africa, in
general and lagoon in particular (Adeaga et al.,
2017), in a context of environmental crisis, leads
to a reflection on the functioning, the evolution,
as well as the management of the use of resources
of lagoon spaces. Thus, the development of
this new theme with that of eco-hydrology is
necessary to better characterize the hydrological
and sedimentary dynamics of the environment in
the context of global changes and sea-level rise,
already impacting most coastal areas around the
world.

4.1.6 Asian Pacific (AP)

In the Asian Pacific region, water resources in many
countries are affected by climate change (Yang et
al., 2019). Increasing dry season duration, longer
and more severe droughts could cause water
shortage on a large scale and reduce water quality,
strongly affect water security and sustainable
development. Besides, rising sea levels lead to
flooding in the delta and coastal areas, increasing
saline intrusion in estuaries and coastal plains and
causing erosion to upset the natural and ecological
balance (Li et al., 2018), seriously affecting coastal
areas. Thus, research is needed to provide useful
information and solutions related to ensuring water
security in the context of climate change.

The downstream regions of international rivers are
often suffering from water-related disasters (Try
et al., 2018), facing water scarcity and declining
water resources due to overexploitation Thus,
water resources in Asian countries are hiding many
unsustainable factors for development (Kondolf et
al., 2018). Water scarcity and shortage will increase
sharply compared to today and most river basins
are already in a state of stress on water use (Hiraga
et al., 2018), especially during the dry season. Water
tensions will be severe in key economic basins
(Kositgittiwong et al., 2017). Thus, one important
topic in Asia is how to reduce the stress on water
use, especially during the dry season.

Due to rapid increase of population, industrial and
agricultural production, pollution of surface waters
has been increased in both level and scale (Zhang
et al., 2018; Nguyen et al., 2019). Water is available
in many places but cannot be used due to its poor
quality. Especially, surface water and ecohydrosys-
tems in many urban areas and industrial parks
have been seriously affected due to the untreated
or incompletely treated wastewater discharge.
In some countries in AsiaPacific, the lack of large
investment in industrial and urban wastewater
treatment, no effective mechanisms and policies
to reduce water pollution, the overuse of fertilizers
and chemicals in the agricultural sector, among
others, have accelerated pollution levels in this
region. Thus, the development of research focused
on minimizing water degradation is firstly needed
(Le et al., 2017; Uk et al., 2018).
Rapid increase in water demand accelerates groundwater exploitation, leading to its over-exploitation. Groundwater level in some areas has been continuously reduced and, more importantly, its quality faces a high risk of pollution (e.g by arsenic)(Hoa et al., 2020). Thus, future studies should be focused on providing information concerning the reasonable exploitation of groundwater and the protection of both quantity and quality of groundwater.

### 4.1.7 Nile Basin

The FRIEND supported Water Research Centre is a multidisciplinary research and capacity building center established by the University of Khartoum in 2009 with the aim of conducting multi-disciplinary research and development studies addressing the challenges related to water and environmental management in Sudan and the region (Salih, 2018; Basheer et al., 2018). One of the top priority research areas is trans-boundary water management in the Nile basin. Demand for water throughout the basin is constantly growing due to economic development and population growth. Following this rapidly increasing demand, riparian countries have acknowledged the need for joint planning and management. Numerous studies have demonstrated that the river has

great potential which, through sustainable and cooperative management and development, could greatly benefit all the basin countries. A research area of specific interest to the Water Research Centre is the water-energy-food (WEF) nexus investment and management in the basin. The WEF supply pressures, the growing understanding of the interlinkages between the three resources, and the failure of fragmented management of the different WEF sectors have led to the emergence of such water-energy-food nexus thinking. Although WEF in stressed transboundary Basins such as the Nile are subject to high pressure due to competition between riparian countries over the three resources, a systematic understanding of how cooperation between riparian countries impacts the WEF nexus is still lacking (Wheeler et al., 2018, Basheer and Elagib, 2019). Another transboundary management challenge is the coordinated operation and management of new water-related infrastructure across the basin's international borders. This is particularly true given that water rights are highly politicized and decisions of exploitation are often guided by ambitious national development plans and complex political dynamics. A good example is the Grand Ethiopian Renaissance Dam (GERD) on the Blue Nile which makes cooperative management between the countries of Ethiopia, Sudan, and Egypt an urgent

<figure><img src="image_13.png" /></figure>
matter. To enhance confidence building and
enhance cooperation in the Nile Basin the Water
Research Centre has developed a strategy for
training and capacity building in Water Diplomacy
and Cooperation (Salih, 2019). A number of
workshops have been conducted in which partic-
ipants from the Nile Basin countries from relevant
disciplines were brought together and trained on
transboundary water governance and institutions,
water laws and conventions, concepts of conflict
and conflict resolution mechanisms, negotiations
and mediation concepts, role of media in water
diplomacy, the role of women in water diplomacy
and the role of science in supporting negotiations
and water cooperation.

Another important research area in WRC is the study of hydrological extremes. Sudan, being situated on the eastern edge of the African Sahel, is a well-documented region facing the problems of climatic change/variability and rainfall fluctuations creating severe floods and drought scenarios (Abdo, 2019). Over the past 50 years, Sudan has encountered a number of high flash floods and droughts that have caused widespread damage on a massive scale to the infrastructure, agricultural, health and educational sectors, as well as loss of human and animal lives. Other research areas the Centre are involved in irrigation management and water use efficiency, water harvesting and management of groundwater recharge, urban water management, ecohydrology, water quality management and groundwater assessment, development and management (Basheer et al., 2019).

In 2014, the WRC was promoted to a Centre of
Excellence in Water Research by the Ministry of
Higher Education and Scientific Research. In 2017,
WRC was selected as one of the AU-NEPAD Centers
of Excellence in Water Science and Technology in
Africa and it is now hosting the secretariat of the
group of centres in Central and Eastern Africa. Over
the years, WRC has developed scientific collabora-
tion with many universities, research institutions,
specialized networks and programs – nationally,
regionally and internationally. These include
UNESCO International Hydrological Programme
(IHP), Global G-Wadi (Water and Development
Information), African G-Wadi, Arab G-Wadi,

International Flood Initiative (IFI), International Sediment Initiative (ISI), World Bank-Nile Basin Initiative (NBI), Eastern Nile Technical Regional Office (ENTRO), UNESCO-IHE, Delft in the Netherlands, UNECEF, Cologne University of Science and Technology in Germany, Imperial College of Science and Technology in London, and Oxford University, as well as many regional universities as Addis Ababa University, Nairobi University, Kenyatta University, Dar es Salam University, Cairo University, and Ain Shams University. WRC has participated in the two phases of the FRIEND/NILE project and produced a number of papers in the flood frequency, low flow frequency, watershed management and rainfall runoff modeling components.

4.1.8 Congo Basin

As referred in the study of Alsdorf et al. (2016), the Congo River basin (CRB), although being the second largest river in the world by discharge, remains largely understudied. It is thus very important to strengthen the research and knowledge capacity in this region of the world, based on the emerging new research teams over the many countries that share the Congo River (Beighley et al., 2019; Trigg and Tshimanga, 2020).

The Congo River Basin exhibits tremendous heterogeneities, out of which it emerges as an intricate system where complexity will vary consistently over time and space. Increased complexity in the absence of adequate knowledge will always result in increased uncertainties. One way of simplifying this complexity is through an understanding of organisational relationships of the landscape features, which is termed here as catchment classification (Tshimanga et al., 2020). This is one of the major tasks to start with at the international level, in order to develop further multidisciplinary studies on the basis of this global knowledge shared among all teams. During the past 12 months, there has been a first attempt to establish a framework of catchment classification using an a priori approach. Various methods, including GIS and multivariate analyses, were combined to define the sub-basin units and group them in homogeneous regions. A set of 1740 catchment units were partitioned across
<figure><img src="image_14.png" /></figure>

©Sergey Uryadnikov/shutterstock.com

the whole Congo River Basin, based on a set of comprehensive criteria, including the natural break of the elevation gradient (199 units), inclusion of socio-economic and anthropogenic systems (204 units), and water management units based on traditional (socio-hydrology) nomenclature of the rivers within the basin (1337 units). The identified catchment units were used to assess existing datasets of the basin physical properties, necessary to derive descriptors of the catchments characteristics. Assessment of relationships between physical basin attributes showed that 15 variables out of the 26 initially selected contained the information necessary to explain the spatial distribution and grouping of the sub-basins. These 15 variables were included in a cluster analysis using unsupervised classification (hierarchical agglomerative clustering), which identified 11 groups of homogenous catchments based on the use of the environmental descriptors derived from the available physical basin property datasets. This constitutes therefore an a priori clustering of the catchment classification framework for the CRB and should be considered as an initial phase of the iterative process of catchment classification. This clustering will be further used to derive functional

relationships of the catchments, necessary to enable hydrological prediction and water management in the basin.

The framework is therefore an efficient tool that will help synthesize the understanding of the interaction between climate variability, catchment characteristics (e.g. vegetation, soils, topography) (Mushi et al., 2019) and the resulting hydrological response. It is also a crucial step in improving predictions in ungauged basins, and the new insights of the Congo river hydrology obtained from the most recent field campaigns will help improve the accuracy of the satellite derived hydrological data (Carr et al., 2019).

Within FRIEND-UNESCO, it is intended to promote the use of this framework to address the challenge of generalizing knowledge derived from local observations and understanding of the catchment response characteristics, as well as the underlying process controls; to provide guidance for measurement and modelling, and constraints for predictions in ungauged basins and to estimate impacts of environmental changes.
## 4.2 Ecohydrology, a key interest for the future FRIEND-Water programme

Recent discoveries on the importance of living things and their environmental feedbacks, on the role of homeostatic processes and breakpoints confirm that global warming is only part of the current ecological crisis also manifested by the loss of biodiversity, the loss of soil fertility, water pollution but also the drastic increase in diseases that affect the entire living world. The water cycle is at the center of all of these interlocking systems. It also becomes obvious to hydrologists that it is essential to cross the scales of spatial studies, from large to small watersheds, and vice versa. Understanding the why of a hydroclimatic rupture and its consequences will therefore require interdisciplinary perspectives and as such ecohydrology must belong to the research corpus of hydrologists.

Indeed, the spatial analysis of human pressure on natural resources and of the required ecosystem services according to the hydrological logic and a systemic approach of the ecosystems makes possible to understand cause-and-effect relationships along the watershed. The understanding of the water flow pathways and the associated dissolved and suspended matter fluxes drives to optimize nature-based eco-engineering solutions. Based on the management of all the liquid and solid fluxes inside the watershed, the ecohydrological approach promotes to restore and often to amplify the key ecosystem functions in regards of the human uses and needs. The purpose of this approach concerning the integrated management of ecosystem services at watershed scale is to organize and to optimize the use of ecosystem services along surface flows according to their nature. In this context, significant challenges of scientific fields appear to be addressed: i) Developing dynamic hydrological models based on changing environmental conditions (e.g. soil-water dynamics); ii) Climate change and sustainable ecological transition (e.g. urban-rural association); iii) Nature-based solutions as a rising awareness towards environment (e.g. REUSE-Soil-Biodiversity nexus); and iv) Rainwater management in urban areas (e.g. flashfloods).

For this reason, ecohydrology is among the key words of the future FRIEND-Water programme. Aligned with the IHP-IX goal to achieve Sustainable Water Management, the FRIEND-Water programme will get some interests to incorporate the ecohydrology among its key tools. The Ecohydrology theme (EH) is a part of IHP's ambition to enhance solution-oriented approaches for the enhancement of Water resources, Biodiversity and ecosystem Services for society and of the Resilience to various forms of anthropogenic impacts (WBSR). Due to the lack of hydrological monitoring in developing countries, the knowledge of regional hydrology dealing with water resources and its extremes is necessary to develop regional Ecohydrology programmes. The partnership between EH and FRIEND-Water should bring great advantages to achieve the IHP-IX goal on the Sustainable Water Management (SWM). In early 2018, the two programmes have decided to organize a special joint-session on "Collaboration between FRIEND & EcoHydrology networks" at Beijing, November 8th 2018, during the 8th Global FRIEND-Water Conference (6-9 Nov. 2018). The motivation for this workshop was to figure tracks of collaborations between FRIEND – a cross cutting IHP programme – and EcoHydrology IHP theme.

From that workshop resulted the following list of expectations for IHP-IX:

* Recall for problem solving methodologies which can address the water securities challenges in face of CC and world's population growth;

* IHP-IX seeking for problem solving approaches;

* Need to reactivate "Experimental Representative Research Basins" as to better understand the effect of the no longer stationary relationship on which water management projects were based in the past;

* Better figure out how EH can cope with MDGs goals and other international trends;

* Coastal and lake food production management is an important concern for which interest of EH should be managed;
* How EH could address water extremes, flood & drought;

* Develop Ecohydrology partnerships with Asia, especially on Urban EH;

* Interest of EH for GW management needs to be better explained, collaboration with GWADI should be encouraged;

* Better figure the soil compartment in the biochemical reactors of EH.

The workshop also led to the definition of future actions including the development of common ERBs (Experimental and representative Basins) between UNESCO programs where EH, amongst other approaches, could make effective the experience gained, to demonstrate from the field on how an appropriate land management, in combination with eco-engineered solutions, would contribute the water security objectives. It was also highlighted the importance of cross invitation between FRIEND & EH to participate dedicated sessions during their conferences, contribute to training and master classes, including field trips, for tangible problem analysis.

EH is a Problem Solving Method based on manageable drivers in terms of hydrology and biota (dual regulation). It has consequences on the land management and water flow management. The scale to which EH can be efficient is case dependent, but it will depend on the decision maker level which has the power to act on the identified drivers. There is still a need to demonstrate that EH methodology is efficient – developing demosites (ERBs) - which better fits with rapid decision, people empowerment, and reactiveness.

Since 2011, UNESCO-IHP promotes the establishment of various demonstration sites around the world to apply Ecohydrology solutions in watersheds at all scales. Each demonstration site aims to apply Ecohydrology principles and solutions to solve both social and environmental issues. These solution-oriented projects and methodologies are shown in a web-platform<fnref n="3" /> to disseminate the acquired information to UNESCO's

Member States and the general public. This information is dedicated to allow to apply SWM in other locations. The opening of 2 joint EH-FRIEND demosites (ERBs) is planned, one in Tunisia dealing with water quality remediation in highly polluted environments (around Bizerte), in relationship with surface and groundwater hydrology; another one in West Africa in Senegal, (Breil et al., 2020; Faty et al., 2020), called Dakar'2030, dealing with the combination of rainwaters and wastewaters management in the region of Dakar to water and re-green soils against soils and sea pollution.

Several other FRIEND-EH actions were cross-planned:

* Participation of FRIEND-Water in the international EH Seminar at Faro (Portugal), 28-30 September 2020 has been converted into a webinar, expected to deliver enough scientific material to promote the EH applied to large river basins.

* Participation of EH to the international FRIEND-Water /AOC Conference at Cotonou (Bénin), 16-20 November 2021. The one-day training on Ecohydrology was also postponed due to the Covid-19 pandemic. The international FRIEND-Water /AOC Conference at Cotonou (Bénin) have been postponed to 16-20 November 2021 with the same engagement for the EH contribution. A one-day training on Ecohydrology will be planned.

* It is expected to hold a collaborative international seminar between FRIEND-Water and EH, with also the international group SWAT, at Dakar in 2022.

The members of the former project group 5 from the EURO FRIEND-Water group, who were associated with the Euro-Mediterranean Network of Experimental and Representative Basins (ERB), might be interested to jointly improve knowledge on ecohydrology and run their equipped catchment as an ecohydrological demonstration site. They operate well instrumented experimental

<footnote n="3">3 http://ecohydrology-ihp.org/demosites/#demosites</footnote>
and representative catchments for hydrological
and environmental research on a long term in 22
European countries.

The FRIEND-Water programme has many opportu-
nities to involve its own ecohydrology discussions
and projects to contribute to the water-
environment-energy-food-health nexus, which
should not solely focus on hydrological processes
to be able to answer to the Society demands. The
basic solution should apply nature-based solutions
(NBS) and problem solving learning (PSL), ensuring
active participation from the actors. Competencies
give a clear direction and contextualization of the
learning process, hence transferable from one
learner to the next. The technological implementa-
tions to a solution that produces tangible outputs,
will help visualization and impact assessment
of learning actors. Then, ecohydrology will offer
new opportunities for FRIEND-Water to pass
achievements to policy makers and the public
through more active developments in social
media. Ecohydrology will also push to re-develop
the data sharing and experiences about database
management and information systems. Then
links with WINS (UNESCO-IHP Water Information
Network System) should be explored. At last, eco-
hydrology will open potential options to cooperate
with several UNESCO water-related Chairs. A few
chairs also touch upon water and health, which is
also done by the UNESCO World Water Assessment
Programme (WWAP).

4.3 Database development and support

Regarding the accessibility of data and open
access data, the accent should be put on how
to connect directly to existing web databases as
well as to develop APIs to deal with connectivity
issues. In some countries, even if there is open data,
challenges refer to the infrastructure, as commu-
nication networks focus on mobile phones and
the facility to upload data is not always there. It is
necessary to address this, including the question of
communication software.

The world water data centres federated within
the Global Terrestrial Network-Hydrology (GTN-H)
inter alia the GRDC, the GEMS/Water Data Centre
for Water Quality (GWDC), the International Soil
Moisture Network (ISMN), the Global Groundwater
Monitoring Network (GGMN, operated by
IGRAC) mostly operates under auspices of UN
organizations such as the WMO, United Nations
Enviornmental Programme (UNEP) or UNESCO
and can guarantee long-term operational services
to the scientific communities and local stake-
holders worldwide since decades. These data
centres should be recognized and considered for
data rescue due to their long-term provision of
homogenized and quality-assured in-situ obser-
vations. Vice-versa, FRIEND communities could
support the data centres in raising awareness of
difficulties in data acquisition as well as lags in open
data policies and technical requirements (e.g., APIs,
provision of standards).

Research is also necessary for linking in-situ with
satellite-born observations. Also here FRIEND could
play a crucial role. Exchange of experiments, of data
treatment, but also solutions could be organized
through UNESCO Water family so that sharing data
must become an open space in the entire UN Water
family.
<figure><img src="image_15.png" /></figure>

©Nowaczyk/shutterstock.com

5 Looking forward:
# FRIEND-Water in the context of IHP-IX, 2030 Agenda and Paris Agreement

How to develop FRIEND activities in regard of the main objectives of the IHP-IX program, and of the specific targets of the FRIEND-Water program? The FIGCC functioning will be aligned according to changes following IHP initiative guidelines approved in the 24th IHP council, 28-30th of June, 2021.

UNESCO-IHP has just entered its ninth phase, dedicated to develop "Science for a Water Secure World in a Changing Environment". The IHP-IX (2022-2029) represents a methodological response towards transdisciplinarity to achieve a water secure world in today's complex context. Its

strategic plan divides these ambitions into five priority areas and 34 outputs. The IHP-IX Priority Areas, identified and elaborated by UNESCO's member states are:
1 **Scientific Research and Innovation;**

2 **Water education in the Fourth Industrial Revolution including Sustainability;**

3 **Bridging the data-knowledge gap;**

4 **Integrated water management under conditions of global change; and**

5 **Water governance based on science for mitigation, adaptation and resilience.**

FRIEND-Water goals and activities outlined in this report are expected to significantly contribute to the IHP-IX outcomes, particularly those defined under Priority Areas 1, 2 and 3.

With water assuming an increasingly central role in climate change discussions, it also is expected that FRIEND-Water Programme objectives become increasingly aligned with the goals defined in the Paris Agreement, the 2030 Agenda and the Sustainable Development Goals (SDGs), supporting each region in the path to achieve a resilient and sustainable water management.

All current activities of the FRIEND-Water programme are expected to be continued (conferences, workshops, training sessions, field

trips). New activities are also awaited. For instance, it is foreseen that each FWRC prepare a synthesis of the scientific and development priorities to be developed in its region in the coming years. The FRIEND Secretariat will synthesize all regions contributions to set an updated panorama of scientific priorities across the regions, and help guiding future FRIEND-Water activities. This material is expected to be compiled and presented as a prospective paper which should be written every 4 years and submitted to a journal, or published in the Proceedings of IAHS (PIAHS) after each Global FRIEND-W conference. New actions must be developed towards a large audience and towards youth, to largely disseminate knowledge in a simplified manner. The FRIEND Secretariat will likewise follow this process with care.

It is highly recommended the development of connexions with other water-related Flagship Initiatives of UNESCO to take an improved advantage of the vast experience among the Water Family, as it is already the case by the connexion between World Large Rivers Initiative (WLRI) and FRIEND-Water, and between the Ecohydrology programme and FRIEND-Water. Even so, these connexions would benefit from being further developed.
6

References

The references below are issued from
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<figure><img src="image_16.png" /></figure>

7 Annexes
# ANNEX 1

## List of current FRIEND-Water
Regional Coordinators

### European FRIEND-Water (EURO)

**Stephan Dietriech**

Coordinator of the Global Terrestrial Network of Hydrology (GTN-H; WMO/GCOS initiative)

International Centre for Water Resources and Global Change (ICWRGC), UNESCO Category 2 Centre

Secretariat German IHP/HWRP National Committee. Hosted by the Federal Institute of Hydrology

Germany

dietrich@bafg.de

### Mediterranean FRIEND-Water (MED)

**Mohammed Meddi**

Professor in Hydraulics and hydrology in the National Higher School of Hydraulics

Algeria

h.meddi@ensh.dz

And vice-coordinator:

**Oula Amrouni**

INSTM Researcher/ Marine & Coastal Geology
University of Carthage

Tunisie

oula.amrouni@instw.rnrt.tn

### Latin American & Caribbean FRIEND-Water (AMIGO)

**Santiago Yepez**

Assistant Professor

Universidad de Concepción, Departamento Manejo de Bosques y Medio Ambiente

Concepción,
Chile

yepez14@gmail.com

### Southern Africa FRIEND-Water (SA)

**Patrick Valimba**

University of Dar Es Salaam
Tanzania

pvalimba@yahoo.com

and vice-coordinator:

**Telesphore Brou Yao**

University of La Réunion, Reunion Island, France

telesphore.brou@univ-reunion.fr

### West & Central Africa FRIEND-Water (AOC)

**Ernest Amoussou**

University of Parakou

Benin

ernestamoussou@gmail.com

### Asian Pacific FRIEND-Water (AP)

**Le Thi Phuong Quynh**

Institute of Natural Product Chemistry (INPC),

Vietnam Academy of Science and Technology (VAST)

Vietnam

quynhltp@yahoo.com

### FRIEND CONGO

**Raphael Tshimanga**

Hydrology and Water Resources Expert, Congo River Basin.

FLAIR Fellow, Royal Society/African Academy of Sciences, CRREBaC (Congo Basin Water Resources Research Center), University of Kinshasa,

DR Congo

raphael.tshimanga@unikin.ac.cd

### FRIEND-Water NILE (FN)

**Gamal Abdo**

Director, Water Research Center
University of Khartoum

Republic of the Sudan
gabdo2000@yahoo.com
# ANNEX 2

## Summary of Beijing's 2018 Global FRIEND Conference

The following paragraphs are copied from the preface of the PIAHS volume issued after the Beijing FRIEND Global Conference on Hydrological Processes and Water Security in a Changing World, in November 2018, by Zhongbo Yu,¹ Chunhui Lu,¹ Jianyuan Cai,² Dazheng Yu,² Gil Mahe,³ Anil Mishra,⁴ Christophe Cudennec,⁵ Henny A.J. Van Lanen,⁶ Didier Orange,⁷ and Abou Amani⁸

¹ State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China

² Department of Hydrology, Ministry of Water Resources, Beijing, China

³ HSM, Hydrosciences, IRD, UM, CNRS, MSE, 34090 Montpellier, France

⁴ UNESCO, Division of Water Sciences, 7 place de Fontenoy, 75352 Paris Cedex 07, France

⁵ UMRSAS, Institut Agro, INRAe, 35000 Rennes, France

⁶ Hydrology and Quantitative Water Management Group, Environmental Sciences Department, Wageningen University, Droevendaalsesteeg 3a, 6708 PB, Wageningen, the Netherlands

⁷ Eco&Sols, UM, IRD, CIRAD, INRAe, SupAgro Montpellier, 34090 Montpellier, France

⁸ UNESCO, Natural Science Sector, 7 place de Fontenoy, 75352 Paris Cedex 07, France

The world's freshwater environment is changing rapidly and facing unprecedented pressures. A growing global population and economic development have led to increasing demands on water resources and water management. The impact of climate change and intensive anthropogenic activities is now posing a great threat on the hydrological cycle leading to various water issues, such as floods, droughts, over-exploitation of water resources, pollution, and ecosystem degradation in many countries. On a global scale, more than two billion people live in countries experiencing high water stress. Consequently, understanding hydrological responses to stresses at local, regional and global scales is critical for addressing these water issues, including water resources planning and management for everywhere on the planet.

In order to advance the knowledge of hydrological processes and flow regimes in different regions, UNESCO initiated in the 1980s the Flow Regimes from International Experimental and Network Data (FRIEND) programme (van Lanen et al., 2014), within the framework of Intergovernmental Hydrological Programme (IHP). The FRIEND programme is an international research programme that helps to set up regional networks for analyzing hydrological data. It aims to develop better understanding of hydrological variability and similarity across time and space, through the mutual exchange of data, knowledge and techniques at the regional level. FRIEND's track record shows its strengths as a global network supporting a science-based network of high-level hydrological research at the river basin level and larger scales. These activities undertaken by FRIEND regional scientific groups of researchers, resulted in several topics related to regional hydrology and scientific
publications, which is a contribution on water security within the framework of the IHP VIII and beyond to water related sustainable development goals (SDGs) of the United Nations Agenda 2030 for sustainable development, Paris Agreement and Sendai Framework.

The 8th Global FRIEND conference was co-organized by UNESCO and Government of China from Nov. 6th-9th, 2018 in Beijing, with the focus on the theme of hydrological processes and water security in a changing world, under which eight thematic topics were discussed during the conference: (1) Hydrological observations under the changing environment and scarcity; (2) River regimes and hydrological extremes under the changing environment; (3) Simulation and prediction of surface water and groundwater processes under the impact of human activities; (4) Urban hydrology and sponge city; (5) Multi-objective water resources allocation and operation; (6) Integrated watershed management including eco-hydrology and socio-hydrology; (7) Water quality and sediment transport; and (8) River health and ecological baseflow under changing environment. The conference explored how society, water systems and the environment interact under changing conditions. It highlighted the advance in hydrological science and innovation in water management, as well as the solutions to improve this relationship, particularly in view of contributing to the 2030 Agenda and the Paris Agreement. For the first time the two IHP programs FRIEND and Ecohydrology jointly organized a side event about the importance to bring ecological solutions to hydrological problems.

The series of FRIEND conferences, workshops and scientific publications since 1989 are proven to be essential for fostering cooperation among FRIEND network and beyond. More than 200 participants from 44 countries attended the 8th Global FRIEND conference. This conference reminded that knowledge from all parts of the world need to be shared to improve our capacity to manage water as a common resource. More than 100 papers were presented at the conference. Eighty-nine papers were submitted for publication in this PIAHS volume, from which eventually 52 papers were accepted. These papers cover study areas in precipitation and climate impact; observation, analysis

and simulations of hydrologic processes; floods in the changing environments; droughts monitoring and analysis; water resources and environmental impacts.

Quantifying the natural and anthropogenic impacts on the hydrological processes and water resources are very important in current research efforts to understand how hydrological processes vary among climates and through time, as regional and global climates undergo change, and how modified hydrological processes affect water resources at different scales. Despite that many advances in these research areas have been achieved, the comprehensively integrated data and multidisciplinary approaches are required to address solutions for the implementation of SDGs and particularly water related targets. Furthermore, the outcome of the conference presented in the proceedings will be shared and discussed widely among IHP networks which would lead to recommend inputs for sustainable water resources management at different scale, but also provide feedbacks for the preparation of strategic plan for the 9th phase of IHP (2022-2029).

The hydrological mechanisms, including flood and drought events, pollutions and water scarcity, underlie the climate-soil-vegetation dynamics and control the most basic ecological patterns and processes, both for biota and materials. Then the regional hydrology and flow regime characterization can emphasize the comprehension and role of the hydrological template that regulates ecohydrological functioning of the nature. Hydrological processes and water security are intrinsically linked to ecological and societal based approaches for watershed management. The future effort is at the nexus of water-soil-energy-food; and the related fields of geoinformatics, cyberinfrastructure in watersheds and remote measurements for scientific studies and water resources assessment should be helpful.

### Reference

Van Lanen, H.A.J., Demuth, S., Daniell, T., Hannah, D.M., Laaha, G., Mahe, G., Tallaksen, L.N. (2014). Over 25 years of FRIEND-Water : an overview. In: *Hydrology in a Changing World: Environmental and Human Dimensions*. Proceedings of FRIEND-Water 2014, Montpellier, France, October 2014 (Daniell, T. et al., Sci. Ed.), IAHS Publ. 363, 1-7.
# ANNEX 3

## FRIEND-Water meetings 2014-2021

### Europe (EURO)

<table><thead><tr><td>Project Group</td><td>Event</td><td>City, Country</td><td>Date</td></tr></thead><tbody><tr><td>European Water Archive</td><td>No specific meetings (EWA is integrated in the Global Runoff Data Centre, GRDC). State of EWA is discussed in GRDC Steering Group every two years.</td><td></td><td></td></tr><tr><td rowspan="10">Low Flow and Drought</td><td>Leonardo Conference "Hyper Droughts"</td><td>Prague, Czech Republic</td><td>November 2014</td></tr><tr><td>Annual Splinter meetings at EGU</td><td>Vienna, Austria</td><td>April 2015</td></tr><tr><td>Drought Conference DROUGHT: Research and Science-Policy Interfacing (DROUGHT-R-SPI)</td><td>Valencia, Spain</td><td>10-13 March 2015</td></tr><tr><td>Mid-term group meeting</td><td>Wallingford, UK</td><td>September 2015</td></tr><tr><td>Annual Splinter meetings at EGU</td><td>Vienna, Austria</td><td>April 2016</td></tr><tr><td>Annual Splinter meetings at EGU</td><td>Vienna, Austria</td><td>April 2017</td></tr><tr><td>End-term group meeting and workshops</td><td>Freiburg, Germany</td><td>11-13th October 2017</td></tr><tr><td>Annual Splinter meetings at EGU</td><td>Vienna, Austria</td><td>April 2018</td></tr><tr><td>Workshop on Hydrological Drought Textbook meeting</td><td>Drobak, Norway</td><td>14-18 January 2019</td></tr><tr><td>Annual Splinter meetings at EGU</td><td>Vienna, Austria</td><td>April 2019</td></tr><tr><td rowspan="7">Large-scale variations</td><td>AGU Fall meeting 2015<br/>Session: Teleconnections in Hydrological Systems at Decadal Timescales: Challenges for Hydrological Modeling and Projection Uncertainties</td><td>San Francisco, USA</td><td>16 Dec 2015</td></tr><tr><td>EGU General Assembly 2015<br/>Session: Large scale hydrology</td><td>Vienna, Austria</td><td>14 Apr 2016</td></tr><tr><td>EGU General Assembly 2016<br/>Session: Large scale hydrology</td><td>Vienna, Austria</td><td>19 Apr 2016</td></tr><tr><td>EGU General Assembly 2016<br/>Session: Large-scale climate variability and its impact on hydrological systems</td><td>Vienna, Austria</td><td>22 Apr 2016</td></tr><tr><td>AGU Fall meeting 2016<br/>Session: Large-Scale Climate Variability and Its Impact on Hydrological Systems, Water Resources, and Population</td><td>San Francisco, USA</td><td>14 Dec 2016</td></tr><tr><td>EGU General Assembly 2017<br/>Session: Large scale hydrology</td><td>Vienna, Austria</td><td>28 Apr 2017</td></tr><tr><td>EGU General Assembly 2017<br/>Session (splinter meeting): Euro-FRIEND-Water Project 3 EGU meeting "Large-scale variations in hydrological characteristics"</td><td>Vienna, Austria</td><td>28 Apr 2017</td></tr></tbody></table>
<table><thead><tr><th>Project Group</th><th>Event</th><th>City, Country</th><th>Date</th></tr></thead><tbody><tr><td></td><td>AGU Fall meeting 2017<br/>Session: Challenges Understanding the Links Between Hydrological Variability and Large-Scale Climate Variations in a Changing Climate and Environment</td><td>New Orleans, USA</td><td>14 Dec 2017</td></tr><tr><td></td><td>EGU General Assembly 2018<br/>Session: Large scale hydrology</td><td>Vienna, Austria</td><td>11 Apr 2018</td></tr><tr><td></td><td>EGU General Assembly 2018<br/>Session: Challenges understanding the links between hydrological variability and large-scale climate variations in a changing climate and environment</td><td>Vienna, Austria</td><td>12 Apr 2018</td></tr><tr><td></td><td>FRIEND-Water FIGCC meeting at the 8th FRIEND-Water Conference,</td><td>Beijing, China,</td><td>November 2018</td></tr><tr><td></td><td>EGU General Assembly 2019<br/>Challenges understanding the links between hydrological variability and large-scale climate variations in a changing climate and environment.</td><td>Vienna, Austria</td><td>10 April 2020</td></tr></tbody></table>

## Mediterranean (MED)

<table><thead><tr><th>Project Group</th><th>Event</th><th>City, Country</th><th>Date</th></tr></thead><tbody><tr><td rowspan="5">All themes</td><td>Conference: The Hydrology of African Large River Basins, 1st Edition</td><td>Hammamet, TUNISIA</td><td>October 2015</td></tr><tr><td>MEDFRIEND Steering Committee meeting</td><td>Hammamet, TUNISIA</td><td>October 2015</td></tr><tr><td>Conference: Water resources and climate change</td><td>Hammamet, TUNISIA</td><td>October, 2017</td></tr><tr><td>Conference: The Hydrology of African Large River Basins, 3rd Edition</td><td>Algiers, ALGERIA</td><td>May 2018</td></tr><tr><td>MEDFRIEND Steering Committee meeting</td><td>Algiers, ALGERIA</td><td>May 2018</td></tr><tr><td rowspan="2">Extreme events</td><td>UNESCO Conference: Our Common Future under Climate Change, Session on Extreme hydrological events: deciphering changes in hazard and risk at different time-scales</td><td>Paris, FRANCE</td><td>June 2015</td></tr><tr><td>Participation to 16th conference PLINIUS on Mediterranean risks, EGU topical conference series</td><td>Montpellier, FRANCE</td><td>October 2018</td></tr><tr><td>Flow Regimes and Water Resources: Assessment of Global Changes</td><td>Workshop FRIEND and MEDFRIEND within the Working Group on spatial hydrology</td><td>Paris, FRANCE</td><td>December 2019</td></tr><tr><td>Coastal ecohydrology</td><td>OpenGIS symposium Building up Open Source for OPENCOAST</td><td>Chania, Crete, GREECE</td><td>July 2015</td></tr></tbody></table>

## Latin America and Caribbean (AMIGO)

<table><thead><tr><th>Project Group</th><th>Event</th><th>City, country</th><th>Date</th></tr></thead><tbody><tr><td>Extreme events</td><td>IFI-FRIEND project workshop on hydrological maximum</td><td>Panama, Panama</td><td>April, 2014</td></tr><tr><td rowspan="2">Extreme events</td><td>Fourth Workshop for the FRIEND IFI Project Hydrological Extreme Phase I.</td><td>Montevideo, Uruguay</td><td>June, 2017</td></tr><tr><td>Meeting of FRIEND IFI coordinators.</td><td>Queretaro, Mexico</td><td>November, 2018</td></tr></tbody></table>
## Southern Africa (SA)

<table><thead><tr><td>Project Group</td><td>Event</td><td>City, country</td><td>Date</td></tr></thead><tbody><tr><td>All themes</td><td>Proceedings FRIEND-Water Conference</td><td>Montpellier, France</td><td>7-10 October 2014</td></tr><tr><td>All themes</td><td>International Conference on Hydrology of the Large River</td><td>Hammamet, TUNISIA</td><td>26-30 October 2015</td></tr></tbody></table>

## West and Central Africa (AOC)

<table><thead><tr><td>Project Group</td><td>Event</td><td>City, Country</td><td>Date</td></tr></thead><tbody><tr><td>Meeting of the FRIEND AOC steering committee</td><td>Revision of hydrological standards<br>Database management<br>Global changes and water resources<br>Extreme events<br>Dynamics of underground flows<br>Ecohydrology<br>Water quality<br>Underground water</td><td>Ouagadougou, Burkina-Faso</td><td>1 to 2 April 2015</td></tr><tr><td>Review Program of Hydrological Norms</td><td>First Experts Meeting of ECOWAS on the Review Program of Hydrological Norms in West and Central Africa Report</td><td>Abidjan, Ivory Coast</td><td>2 to 3 June 2016</td></tr><tr><td>International Conference on the Hydrology of the Large African River Basins</td><td>2nd FRIENDS / UNESCO / International Hydrological Program (IHP) International Conference on the Hydrology of the Large African River Basins</td><td>Cheikh Anta Diop University of Dakar (Senegal)</td><td>27 to 30 November 2016</td></tr><tr><td>Training on the use and valorisation of spatial hydrometeorological data: correction of biases and downscaling</td><td>Workshop use and valorisation of spatial hydrometeorological data: correction of biases and downscaling</td><td>Bingerville International Innovation Center, University Félix Houphouët Boigny (Ivory Coast)</td><td>23 to 27 April 2019</td></tr><tr><td>Optimization of groundwater security through an integrated approach to sanitation and hygiene in the coastal towns of Cotonou (Benin) and Lomé (Togo)</td><td>Launch workshop of Project LIRA2030-GR05 / 19-Cotonou / Lomé</td><td>Grand-Popo (Bénin)</td><td>12 to 14 June 2019</td></tr><tr><td>Review Program of Hydrological Norms</td><td>Workshop of Revision of hydrological standards in West Africa</td><td>Abidjan, Nangu Abrogoua University (Ivory Coast)</td><td>18 to 19 November 2019</td></tr><tr><td>Project of the International Research Group (GDRI) on hydrological standards</td><td>Project design of the International Research Group (GDRI) on hydrological standards</td><td>Research Institute for Development (IRD) at the Félix Houphouët Boigny University (UFHB) in Ivory Coast</td><td>20 to 22 November 2019</td></tr><tr><td>International Conference on the Hydrology of the Large African River Basins</td><td>4th International Conference on the Hydrology of the Large African River Basins</td><td>Cotonou, Benin</td><td>16-20th November 2021</td></tr></tbody></table>
## Asian Pacific (AP)

<table><thead><tr><td>Project Group</td><td>Event</td><td>City, country</td><td>Date</td></tr></thead><tbody><tr><td>IHP Regional Steering Committee for Southeast Asia and the Pacific</td><td>International Conference on Ecohydrology (ICE) "Ecohydrology Approaches Facing the Global Water Environment Challenges"</td><td>Yogyakarta, Indonesia</td><td>10-12 November 2014</td></tr><tr><td>Riverine carbon transfer and carbon emission related to climate change</td><td>1st international conference Source and transfer of organic matters and associated contaminations in River Basin</td><td>Hanoi, Vietnam</td><td>15-17 december 2014</td></tr><tr><td>IHP Regional Steering Committee for Southeast Asia and the Pacific</td><td>International Symposium on "Integrated Actions for Global Water and Environmental Sustainability" in line with the Commemoration of the 70th Anniversary of UNESCO</td><td>Medan, Indonesia</td><td>21-22 October 2015</td></tr><tr><td>IHP Regional Steering Committee for Southeast Asia and the Pacific</td><td>The International and National Water Dialogue on the Delivery of SDG 6 in Mongolia and Wider Asia and the Pacific Region</td><td>Ulaanbaatar, Mongolia</td><td>25 October 2016</td></tr><tr><td>IHP Regional Steering Committee for Southeast Asia and the Pacific</td><td>2nd international conference International conference: Carbon emission and transfers from the river system: impact of climate change and human activities</td><td>Hanoi, Vietnam</td><td>14 – 15 novembre 2016</td></tr><tr><td>IHP Regional Steering Committee for Southeast Asia and the Pacific</td><td>UNESCO-JASTIP Joint Symposium on Intra-Regional Water Security and Disaster Management</td><td>Manila, the Philippines</td><td>15-16 November 2017</td></tr><tr><td>IHP Regional Steering Committee for Asia and the Pacific</td><td>Catalogue of Hydrologic Analysis (CHA) Workshop on flood hazard mapping</td><td>Shanghai, China</td><td>3 November 2018</td></tr><tr><td>IHP Regional Steering Committee for Asia and the Pacific</td><td>An international workshop on Water pollution impacts on carbon export and greenhouse evasion from Asian river systems</td><td>Hohhot, China</td><td>14 – 17 may 2019</td></tr><tr><td>IHP Regional Steering Committee for Asia and the Pacific</td><td>Regional Workshop on Water Education in Asia and the Pacific (UNESCO)</td><td>Jakarta, Indonesia</td><td>2019 4-5 September</td></tr><tr><td>IHP Regional Steering Committee for Asia and the Pacific</td><td>UNESCO Global Ecohydrology Demosite Meeting</td><td>Putrajaya, Malaysia</td><td>2019 1-4 July</td></tr><tr><td>IHP Regional Steering Committee for Asia and the Pacific</td><td>10th International Conference on Asian and Pacific Coasts (APAC 2019)</td><td>Hanoi, Vietnam,</td><td>2019 September 25-28</td></tr><tr><td>IHP Regional Steering Committee for Asia and the Pacific</td><td>Catalogue of Hydrologic Analysis (CHA) publication workshop</td><td>Naypyidaw, Myanmar</td><td>29 October 2019</td></tr></tbody></table>
## Nile Basin

<table><thead><tr><td>Project Group</td><td>Event</td><td>City, country</td><td>Date</td></tr></thead><tbody><tr><td>Workshop</td><td>Urban water management in Khartoum State, For Unesco Khartoum Office,</td><td>Khartoum, Sudan</td><td>January – March, 2020</td></tr><tr><td>Workshop</td><td>Water Energy Food Nexus in the Eastern Nile</td><td>Khartoum, Sudan</td><td>May 2017 – May, 2018</td></tr><tr><td>Workshop</td><td>Climate Change Study in the Sudan,</td><td>Khartoum, Sudan</td><td>Feb 2016 – May, 2017</td></tr><tr><td>Workshop</td><td>Managing Natural Disaster Isk of Flash Floods in Sudan</td><td>Khartoum, Sudan</td><td>February 2016 – May, 2017</td></tr></tbody></table>

## Congo Basin

The Congo Basin FRIEND-Water programme co-organized the Bangui conference (24-26th of October, 2019), particularly the training session on spatial hydrology.
# ANNEX 4

## FRIEND-Water courses 2014-2021

### Europe (EURO)

<table><thead><tr><td>Project Group</td><td>Course</td><td>City, Country</td><td>Date</td></tr></thead><tbody><tr><td rowspan="3">Low Flow and Drought</td><td>Regional DROUGHT workshop</td><td>Bogor, Indonesia</td><td>3-5 August 2015</td></tr><tr><td>Drought and Water Scarcity Education at Different Levels: Challenges to Learn an Interdisciplinary Topic</td><td>Tehran, Iran</td><td>3-5 December 2016</td></tr><tr><td>Workshop "Software and Tools for Low Flow and Drought Assessment" during the end-term group meeting</td><td>Freiburg, Germany</td><td>12 October 2018</td></tr><tr><td>Large-scale variations</td><td>Large Scale Variations in Hydrological Characteristics Workshop</td><td>Mont Saint Aignan, France</td><td>5-6 June 2017</td></tr></tbody></table>

### Mediterranean (MED)

<table><thead><tr><td>Project Group</td><td>Course</td><td>City, Country</td><td>Date</td></tr></thead><tbody><tr><td rowspan="2">All themes</td><td>Bibliometry: indicators and evaluation of scientific publications</td><td>Hammamet, TUNISIA</td><td>October 2017</td></tr><tr><td>Bibliometry</td><td>Algiers, ALGERIA</td><td>May 2018</td></tr><tr><td>Coastal Ecohydrology</td><td>Summer School: Using Open Source GIS software</td><td>Chania, Crete, GREECE</td><td>July 2015</td></tr><tr><td rowspan="7">Flow Regimes and Water Resources: Assessment of Global Changes</td><td>SWAT modelling - Soil Water Assessment Tool</td><td>Hammamet, TUNISIA</td><td>October 2017</td></tr><tr><td>Hydrological modelling</td><td>Hammamet, TUNISIA</td><td>October 2017</td></tr><tr><td>Hydrogeological modelling</td><td>Hammamet, TUNISIA</td><td>October 2017</td></tr><tr><td>SWAT- Soil Water Assessment Tool</td><td>Algiers, ALGERIA</td><td>May 2018</td></tr><tr><td>ATHYS - Hydrological modelling platform</td><td>Algiers, ALGERIA</td><td>May 2018</td></tr><tr><td>Using model outputs in hydrology</td><td>Algiers, ALGERIA</td><td>May 2018</td></tr><tr><td>GIS applied to hydrology</td><td>Carthage, TUNISIA</td><td>October 2016</td></tr></tbody></table>
## West and Central Africa (AOC)

<table><thead><tr><td>Project Group</td><td>Course</td><td>City, Country</td><td>Date</td></tr></thead><tbody><tr><td>Hydro-agro-climatological and chemical modeling</td><td>Training on digital hydro-agro-climatological and chemical modeling with the SWAT model</td><td>IRD/UCAD, Senegal</td><td>1 to 3 december 2016</td></tr><tr><td>Workshop of spatial hydro-meteorological data</td><td>Training on the use and valorisation of spatial hydrometeorological data: correction of biases and downscaling</td><td>Bingerville (Ivory Coast)</td><td>23 to 27 april 2019</td></tr></tbody></table>

## Asian Pacific (AP)

<table><thead><tr><td>Project Group</td><td>Course</td><td>City, Country</td><td>Date</td></tr></thead><tbody><tr><td>Spatial observation by remote sensing images and field measurement</td><td>Planned to be organized<br/>Topic linking spatial observation by remote sensing images and field measurement of suspended sediment and chlorophyll-a in river water.</td><td>Hanoi</td><td>August 2021</td></tr><tr><td>The 24th IHP Training Course</td><td>Forest Hydrology-Conservation of Forest, Soil, and Water Resources</td><td>Nagoya University, Japan</td><td>November 24 - December 7, 2014</td></tr><tr><td>The 25th IHP Training Course</td><td>Risk Management of Water Related Disasters under Changing Climate</td><td>Disaster Prevention Research Institute, Kyoto University, Japan</td><td>November 30 - December 11, 2015</td></tr><tr><td>Modelling application</td><td>+ Calculation of carbon emission at the air - river water interface<br/>+ Modelling application Seneque/Riverstrahler model on riverine carbon transfer</td><td>Hanoi, Vietnam</td><td>2016<br/>(16th - 17th Nov.)</td></tr><tr><td>The 26th IHP Training Course</td><td>Coastal Vulnerability and Freshwater Discharge</td><td>Nagoya University, Japan</td><td>November 27 - December 10, 2016</td></tr><tr><td>The 27th IHP Training Course</td><td>Integrated Basin Management under Changing Climate</td><td>Disaster Prevention Research Institute, Kyoto University, Japan</td><td>December 4 - 15, 2017</td></tr><tr><td>Workshop on Water Quality and Emerging Pollutants</td><td>UNESCO Asia and the Pacific Regional Training Workshop on Water Quality and Emerging Pollutants</td><td>Jakarta, Indonesia</td><td>2018<br/>27-29 November</td></tr><tr><td>The 28th IHP Training Course</td><td>Integrated Basin Management under Changing Climate</td><td>Disaster Prevention Research Institute, Kyoto University, Japan</td><td>November 28 - December 7, 2018</td></tr><tr><td>The 29th IHP Training Course in Kyoto</td><td>Integrated Basin Management under Changing Climate</td><td>Disaster Prevention Research Institute, Kyoto University, Japan</td><td>December 3 - December 12, 2019</td></tr><tr><td>The 29th IHP Training Course in Kyoto</td><td>Changing Global Water Cycle and the Regional Responses</td><td>ISEE, Nagoya University, Japan</td><td>November 27 - December 6, 2019</td></tr></tbody></table>

## Hindu-Kush Himalayas (HKH)

No training courses have been organized by the Hindu-Kush Himalayas FRIEND-Water courses during the period.
## Nile Basin

<table><thead><tr><td>Project Group</td><td>Course</td><td>City, Country</td><td>Date</td></tr></thead><tbody><tr><td>Global G-Wadi Meeting</td><td>Workshop on Advances in Water Resources Management in Arid and Semi-arid Regions</td><td>Khartoum, Sudan</td><td>17th 19th February 2016</td></tr><tr><td></td><td>Workshop on Water Cooperation and Diplomacy in the Nile Basin “Towards Cooperative Water Management; Legal and Developmental Approaches</td><td>Khartoum, Sudan</td><td>13th -17th January, 2019</td></tr></tbody></table>

## Congo Basin

<table><thead><tr><td>Project Group</td><td>Course</td><td>City, Country</td><td>Date</td></tr></thead><tbody><tr><td>Global Monitoring for Environment and Security (GMES & AFRICA)</td><td>Workshop of trainers on space observation applications in water resources management in the Congo Basin and Central Africa</td><td>Bangui, Central African Republic</td><td>24-26 october 2019</td></tr></tbody></table>
# ANNEX 5

## FRIEND-Water publications 2014-2020

### Europe (EURO)

#### Peer reviewed papers

Aksoy, H., Eris, E., Onoz, B., Cetin, M., Yuce, M.I., Selek, B., Aksu, H., Burgan, H.I., Yildirim, I., Esit, M., Unsal Karakus, E. (2018). Frequency analysis of low flows and relation with environmental flow. Dicle University Journal of Engineering, 9(1), 503-514 (in Turkish with extended abstract).

Aksoy H, and Çavuş Y (2019): Drought. Ölçü, Journal of Chambers of Civil Engineers of Turkey, 22-28 (in Turkish).

Andrew, J.T. and Sauquet, E. (2017): Climate Change Impacts and Water Management Adaptation in Two Mediterranean-Climate Watersheds: Learning from the Durance and Sacramento Rivers. Water, 9: 126. http://doi.org/10.3390/w9020126

Bachmair, S., Kohn, I., Stahl, K. (2015): Exploring the link between drought indicators and impacts *Nat. Hazards Earth Syst. Sci.* 15: 1381-1397. http://doi.org/10.5194/nhess-15-1381-2015

Bachmair, S., Svensson, C., Hannaford, J., Barker, L. J., Stahl, K. (2016): A quantitative analysis to objectively appraise drought indicators and model drought impacts. Hydrol. Earth Syst. Sci. 20(7): 2589-2609. http://doi.org/10.5194/hess-20-2589-2016

Bachmair, S., Svensson, C., Prosdocimi, I., Hannaford, J., Stahl, K. (2017). Developing drought impact functions for drought risk management. *Natural Hazards and Earth System Sciences* 17(11), 1947. http://doi.org/10.5194/nhess-17-1947-2017

Bakke, S.J., Ionita, M., and Tallaksen, L.M. (2020): The 2018 northern European hydrological drought and its drivers in a historical perspective. Hydrol. Earth Syst. Sci., 24, 5621–5653. http://doi.org/10.5194/hess-24-5621-2020

Barker, L. J., Hannaford, J., Chiverton, A., and Svensson, C. (2016): From meteorological to hydrological drought using standardised indicators, Hydrol. Earth Syst. Sci., 20: 2483–2505. http://doi.org/10.5194/hess-20-2483-2016

Barker, L.J., Hannaford, J., Parry, S., Smith, K.A., Tanguy, M., and Prudhomme, C. (2019): Historic hydrological droughts 1891–2015: systematic characterisation for a diverse set of catchments across the UK. Hydrol. Earth Syst. Sci., 23, 4583–4602. http://doi.org/10.5194/hess-23-4583-2019

Barreteau, O., Sauquet, E., Riaux J., Gailliard, N. and Barbier, R. (2014): Agent Based Simulation of Drought Management in Practice, Advances in Social Simulation. Advances in Intelligent Systems and Computing, 229, 2014, 237–248.

Beaufort, A., Lamouroux, N., Pella, H. and Datry, T. and Sauquet, E. (2017): Extrapolating regional probability of drying of headwater streams using discrete observations and gauging networks. Hydrol. Earth Syst. Sci. Discuss. https://doi.org/10.5194/hess-2017-630

Beaufort, A., Carreau, J., and Sauquet, E. (2019): A classification approach to reconstruct local daily drying dynamics at headwater streams. Hydrological Processes 33(13): 1896–1912. http://doi.org/10.1002/hyp.13445

Beaufort, A., Lamouroux, N., Pella, H., Datry, T., and Sauquet, E. (2019): Extrapolating regional probability of drying of headwater streams using discrete observations and gauging networks. Hydrol. Earth Syst. Sci., 22(5): 3033–3051. http://doi.org/10.5194/hess-22-3033-2018

Ben Daoud A., Sauquet E., Bontron G., Obled C. and Lang M. (2016): Daily quantitative precipitation forecasts based on the analogue method: improvements and application to a French large river basin. Atmospheric Research, 169, 147–159. http://doi.org/10.1016/j.atmosres.2015.09.015

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