New data opportunities for studying floods and droughts

“What global geospatial datasets are in fact available for the study of floods, droughts and their interplay with societies?”

My supervisor Giuliano Di Baldassarre asked this question during one of our first meetings. We were brainstorming hypotheses and scientific inquiries for my PhD position, focusing on hydrological extremes and GIS analysis on large scales. We started listing a few datasets together with my other supervisors, Johanna Mård and Luigia Brandimarte, but quickly realized that merely one brainstorming session would not be enough for answering this. I therefore started reviewing the data availability as part of my introductory essay, while also structuring a data collection. 18 months later, we have now published our findings in an open-access review paper on WIREs Water, and have made the data collection openly available at Zenodo.

Categories and subcategories of the 124 freely accessible global datasets included in this review

I am very excited about this review paper, not only because it is my first scientific publication, but also because I think that it will be useful to fellow scientists looking for data. The review paper aims to provide a systematic collection of datasets, covering a broad spectrum of environmental and socioeconomic variables. We highlight unprecedented opportunities associated with these global datasets, and also discuss data usability challenges. I hope that this work can guide fellow researchers in their search for geospatial data and, in the long-run, advance the understanding of how floods and droughts interact with societies in a rapidly changing world.

Full reference:

Lindersson, S, Brandimarte, L, Mård, J, Di Baldassarre, G. A review of freely accessible global datasets for the study of floods, droughts and their interactions with human societies. WIREs Water. 2020;e1424.  DOI:

Our work was also promoted on Advanced Science news! Read it here.  

By Sara Lindersson

The role of risk perception in influencing flood losses over time

Do you know the idiom “burying the head in the sand”? The phrase refers to the common but mistaken belief that an ostrich hides its head in the sand as soon as it feels threatened. According to this credence, the ostrich perceives to be at risk but does nothing to change its fate. On the other hand, there is the behavior of the beaver that protects its lair building small dikes with logs. It’s a very proactive animal and very much risk averse. These two very different behaviors imply two very different outcomes when the two animals are threatened by an actual risk.

The same applies to human societies that intentionally or unintentionally choose what and how to fear.

In a recent paper, together with my colleagues Giuliano Di Baldassarre and Frederike Albrecht, I have depicted four different ways of perceiving flood risk, which correspond to four different ideal types of society that perceive and thus respond to risk in distinct ways. Unsurprisingly, societies that tend to neglect existing risks, as the ostrich does, or underestimate risks, are in danger of experiencing high flood losses without the capacity to learn from past events, as they do not adopt adequate measures. As the beaver, societies that attempt to control flood risk through the construction of levees will decrease their total flood losses substantially. However, a dense population in the floodplain that feels safe due to the presence of a levee may experience catastrophic consequences if the levee fails.

In contrast, risk monitoring societies stand out in their ability to maintain high flood-risk awareness and a memory of flood events that guide participatory preparedness measures.

Have a look at our new paper on Hydrological Sciences Journal, it’s free-to-view!

Full reference:

Ridolfi E., Albrecht F. & Di Baldassarre G. (2019) Exploring the role of risk perception in influencing flood losses over time, Hydrological Sciences Journal, DOI: 10.1080/02626667.2019.1677907

By Elena Ridolfi

AGU 2019 Fall Meeting

The year 2019 marked the Centennial of the American Geophysical Union (AGU), and in December a delegation of our team – Elena, Giuliano and Maurizio – joined its yearly Fall Meeting in San Francisco. Besides attending numerous sessions and poster presentations, we had the chance to present ours and our colleagues’ research, which spanned from sociohydrological modelling to remote sensing. 

To celebrate the Centennial, the AGU commissioned a number of papers to leading researchers in various fields of Earth Sciences, in which they had to set the path for addressing future grand challenges in Earth and Space Sciences. Our group contributed with a Sociohydrology paper that we discussed in a previous post. Giuliano, who led the work, presented it extensively on Monday, in the Hydrology visionary session. At the AGU Centennial Plenary, Elena presented it again together with all the other scientists who were commissioned a paper for the Centennial. The session consisted of short 4’ presentations in which the authors highlighted the main points of their research (check the video!). 

Maurizio presented his ongoing research on flood vulnerability and human settlements in the floodplains, as well as the Science Advances paper led by Johanna in which they use night-time light data to explore changes in flood exposure. 

Below some pictures of us in action! 

By Elena, Maurizio, and Giuliano

A systematic comparison of statistical and hydrological methods for design flood estimation

Accurate estimates of design floods are useful for the planning and design of hydraulic structures or the quantification of risks that will arise due to the occurrence of floods. Hydrological literature is replete with numerous ways of estimating design floods and these methods are considered to be either statistical or hydrological. The statistical method (commonly referred to as flood frequency analysis) refers to the fitting of a probability distribution function to records of annual maximum flows at a gauging location. The fitted distribution function is then used to estimate the design flood corresponding to a chosen frequency of occurrence often expressed as a return period. While the hydrological method for design flood estimation refers to the use of a rainfall-runoff model that represent the processes accounted for in the transformation of precipitation to runoff. Given that hydrological and statistical methods are commonly used in research and applied hydrology, the goal of the current study was focused on evaluating the performance of both methods in terms of accuracy and variance of errors in the estimates. The results of the numerical experiments show that both methods under- and outperform each other depending on the performance measure of interest. Following the precautionary principle, it is suggested that both methods be used in any real application since both methods are based on consolidated theories.

Full reference:

Okoli, K., Mazzoleni, M., Breinl, K., Di Baldassarre, G. (2019). A systematic comparison of statistical and hydrological methods for design flood estimation. Hydrology Research, nh2019188,

Link to the paper

By Kaycee Okoli

Drought in the Anthropocene – 2019 Workshop

Last week, together with Claudia Teutschbein, Elena Ridolfi and Sara Lindersson, I attended the annual IAHS Panta Rhei Drought in the Anthropocene 2019 Workshop organised by Margaret Garcia and colleagues from the Arizona State University. The focus of the workshop was on the cascading effects of drought and anthropogenic factors. Moreover, the workshop aimed at strengthening and enlarge the current research network by bringing together researchers from different disciplines and geographical locations.

Inspiring keynotes by Newsha K. Ajami, Kelley Sterle, Greg Husak, Julio Herrera, Amir AghaKouchak and Kelly Helm Smith were planned during the 2-days workshop. At the end of the first day, a dynamic poster session was hosted to share the research activities of different researchers within the working group. In addition, different breakout sessions were organised in order to identify and discuss key research questions and opportunities for future research collaborations. Last but not least, we had social dinners to further strengthen the connection within the group.

This was the first time I have attended the Drought in the Anthropocene workshop and I have truly enjoyed all the moments of this inspiring 2-day event. It was a fantastic experience interacting with researchers from various disciplines and with different backgrounds involved in water related science. With such an amazing benchmark, it will be now challenging, but also motivating, to organise the next Drought in the Anthropocene 2020 workshop in Uppsala.

By Maurizio Mazzoleni

Sociohydrology and the global water crisis

Nothing is permanent except change. To express this concept, Heraclitus metaphorically referred to the change in the symbiotic relationship between water and people using the words: “no man ever steps in the same river twice, for it’s not the same river and he’s not the same man”. The prescient insight of Heraclitus can equally well serve as a metaphor for the global water crisis humanity is facing. Millions of people around the world are affected by increasing drought severity and flood risk, groundwater depletion, ecological degradation, poor sanitation, water pollution and its impact on human health.

I recently published a paper on this subject by leading an interdisciplinary team of scientists, including my colleagues Maria Rusca, Elena Mondino and Johanna Mård, involved in the (Heraclitus-inspired) global initiative Panta Rhei –Everything Flows of the International Association of Hydrological Sciences (IAHS). In our paper, we show that water crises are increasingly connected and are growing in complexity. We argue that water management practice is still dominated by technocratic approaches, which emphasize technical solutions that often result in unintended consequences and unjust outcomes. Sociohydrology is developing a generalizable understanding of the phenomena generated by the interplay between natural, technical and social processes, which can improve water management practice. As such, our paper describes how advancing sociohydrology can contribute to address the global water crisis, and meet the water‐related targets defined by the United Nations’ Sustainable Development Goals (SDGs).

Our article is now published Open Access on Water Resources Research as part of the special collection Grand Challenges in the Earth and Space Sciences celebrating the centennial of the American Geophysical Union (AGU).

Full Reference:

Di Baldassarre, G., Sivapalan, M.,Rusca, M., Cudennec, C., Garcia, M., Kreibich, H., Konar, M., Mondino, E., Mård, J., Pande, S., Sanderson, M.R., Tian, F., Viglione, A., Wei, J., Wei, Y., Yu, D.J., Srinivasan, V. and G. Blöschl (2019). Sociohydrology: Scientific challenges in addressing the sustainable development goals. Water Resources Research, 55,

Link to the Open Access Paper


By Giuliano Di Baldassarre

International Mountain Conference 2019

What location could possibly beat the beautiful mountain-surrounded Innsbruck for a conference dedicated entirely to the thing I love the most?

Mountains are incredible. They provide an escape from every-day life, they connect us with the environment, and most importantly, they provide us what we need the most, water. Fun facts from the IMC: a sixth of the world population relies on glaciers and snow melt for water, and 70% of lowlands either depend or are supported by runoff coming from the mountains.

However, they can be dangerous when put under pressure. I’ve heard in one of the talks that “disasters are related to development”. Especially in mountain regions, hydrogeological hazards turn into disasters when we “push too much”. In the risk governance session we discussed how mountain communities can deal with risk under changing framework conditions.

  • Which measures and tools are required in integrated risk management to deal with current and emerging challenges triggered by natural hazards?
  • How could risk governance be designed to support diverse mountain communities on their way towards “risk competent societies”?

Any thoughts?

Check out my poster here!

By Elena Mondino

Evaluating precipitation datasets for large-scale distributed hydrological modelling

Our understanding of the advantages and limitations of satellite derived precipitation datasets as a forcing to hydrological models has made tremendous progress over the past decade. However, most studies have analysed only the performance of one or few datasets, were limited to selected small-scale case studies or used lumped models when investigating large-scale basins

In our recent publication on Journal of Hydrology we evaluate 18 precipitations datasets used as input in a distributed hydrological model to simulate river flow in 8 large-scale basins. The findings of our study underlined the importance of the proper selection of precipitation products and demonstrated that there is not a unique best performing precipitation dataset for all basins and results are very sensitive to the basin characteristics.

The outcomes of our research are valuable to support the selection of precipitation dataset to achieve reliable model results for global and large-scale applications. This is the first research that attempts to model large-scale basins using multiple global datasets of precipitations within a distributed hydrological model. Our research offers promising results that might be key in assessing flow values in data scarce river basins.

By Maurizio Mazzoleni


HydroSocialExtremes at the International Conference of RGS in London

I attended the International Conference of the Royal Geographical Society (RGS) in London together with two HydroSocialExtremes fellows, Maria Rusca and Elisa Savelli. This event attracted over 1,800 scientists from around the world. I had a chance to interact with both physical and human geographers involved in water related science, and brainstorm about future research work and scientific proposals.

Maria co-organized (with Filippo Menga, Reading University) a fabulous panel entitled “Water matters: infringing the water-society divide through interdisciplinary engagement”, which attracted numerous contributions of high scientific quality. These were presented in three oral sessions corresponding to the three thematic areas of the panel: i) Materiality of water and everyday practices of access, distribution and disposal; ii) Hydrosocial responsibilities and socio-hydrology; iii) Commodification of water quality, health and diseases. Elisa presented her PhD work about inequalities and injustice in the Cape Town water crisis. I was fascinated by seeing a number of fruitful collaborations across multiple disciplines, which I believe will substantially advance our fundamental knowledge about the role of water resources in nature and society.

By Giuliano Di Baldassarre


RGS 2019 Conference: From geographies of trouble to geographies of hope

Just back after the three-day RGS-IBG Annual International Conference which attracted more than 1,800 geographers worldwide to discuss and question their role in our (troubled) time.

As both participant and contributor, I have found it fascinating to observe the effort and the ethical struggle with which those scientists seek answers to questions that nobody ever asked. Concerns which deal with reframing and reshaping our world toward a more just and sustainable path. I have sensed their true engagement in searching the light in the cracks and discovered the work they do with what seemingly does not work. By challenging their ontologies as well as criticizing what is already critical, they disclose unexplored territories and unearned voices.

I attended several sessions that had to do mostly with water. Presenters questioned water hybrid (socio-natural) essence and elaborated upon its political and social unfolding throughout space and time. In their discussions humans are being distanced from the central and dominant role they have took, in order to give that space back to nature. In a way that also water and its ecosystems could reclaim their future. If some geographers would argue how fair it is to lead someone else’s battle, others would answer that we are water and water is us. I will keep those doubts with me and turn these inspiring thoughts into relevant questions for my future research about water and its alarming and uneven scarcity.

By Elisa Savelli