Could you describe how your professional and/or personal experience relate to water? Where does your interest in space technology for water resources management come from?

My first professional experience was an internship in my home country Nepal. During the internship, I had used geospatial analysis to estimate the hydropower potential in rivers all over Nepal. As a national of a data-scarce region, the idea of using freely and publicly available global datasets to solve the world’s pressing problems resonated strongly with me. Since then, I have delved further into the application of frontier technologies to solve societal problems, as well as pursued a master's degree specialized in flood risk management. This has now led me to pursue a PhD in the application of space-borne observations to estimate river discharge.

You undertook your bachelor’s degree in civil engineering, before moving on to a master’s degree in flood risk management. What influenced your decision to shift your focus to flood risk management?

My first full-time job after my bachelor's degree was in earthquake response to the Gurkha Earthquake in Nepal. The job was an incredible opportunity to give back to my community. Further, the job involved extensive travel to multiple remote villages and small towns in my home country. I had the opportunity to work on frontier technologies in disaster risk management. Further, it became obvious that there is much to be gained by improving disaster resilience of communities. This, along with my prior experience working with river systems in Nepal, motivated me to pursue a joint master's program specialized in Flood Risk Management, funded by the Erasmus+ program of the European Commission.

As a PhD Candidate researching radar altimetry for river discharge, can you elaborate on state of the art developments in this field and recent scholarly discussions?

The first thing to know about radar altimeters is that they are special satellites originally developed to measure the sea surface height. The attempt to use this type of satellite to measure river heights (from which we estimate river discharge) means a change of surface the satellite interacts with. From a relatively smooth surface that spans over kilometres, we now get rugged and rough river surfaces and signals reflected by the nearby land. This makes the application of the satellite for river applications challenging and interesting.

A hot topic among experts these days is the recent launch of the so-called SWOT mission (in December 2022) by NASA and the French Space Agency (CNES). This satellite is supposed to provide us with much better data on river systems; allowing for river discharge estimations like never before. The satellite altimetry community is indeed extremely excited about the added details this new mission can reveal – and how this information can be used to tackle the problems of today – from climate change mitigation to the management of our water infrastructure.

The case studies covered in your PhD are located at the North Sea and the Greater horn of Africa, what is particular about rivers in these regions? Why do they represent good case studies for your research?

Countries in the North Sea region such as the Netherlands, Germany, etc. are developed countries in Europe. They have very good on-the-ground river discharge monitoring networks. Further, these data are openly accessible. Hence, we will have an effective way to validate our technique as well as to improve our estimations, capitalizing on the existing on-the-ground river discharge monitoring network for any technique we develop to estimate river discharge using space-borne observations.

In the Greater Horn of Africa region, river discharge data is not publicly available at-large. Moreover, some conflicts and food security concerns are present in the region. These are projected to get worse with the changing climate. Developing river discharge estimation techniques for the region can enable a better management of water systems and with a better management of water resources, agricultural productivity can also improve.

Describe the potential of geospatial technologies and how they are supporting Disaster Risk Reduction efforts.

Geospatial technologies, in some ways, better represent our three-dimensional world than tables and charts can, as many problems are location-based. From how best to carry out search and rescue missions at the immediate onset of a disaster or how to best plan our cities and regions to make them resilient of disasters in the long run – geospatial technologies have a massive role to play in optimizing our resilience against disasters– in all phases of the disaster management cycle, from planning, to emergency response, to long term preparation.

What would you say are the main challenges in applying machine learning models for hydrological inference?

Addressing problems using machine learning requires the availability of large quantities of data from which algorithms can infer patterns. In hydrological use-cases of machine learning, often the volume of data might be limited. Furthermore, hydrological data have spatio-temporal patterns associated with it. These can be tricky to capture in a machine learning model.

In environmental studies, we often hinge on 30 years of data to define a long-term standard pattern of environmental cycles. However, with climate change, the assumption of a long-term stationary pattern is no longer valid. While observing our river systems, we need to consider that they are changing over time, even more so considering human interventions such as dams and reservoirs, building of big cities around them and pumping of water etc. This dynamic nature of hydrological data, I believe, is one of the main challenges of the application of machine learning models in hydrological studies.

What goes into the performance evaluation of machine learning algorithms for surface water, groundwater, and drinking water quality monitoring?

The performance evaluation approach in general varies depending on what specific problems we are trying to solve with our machine learning model. Often it is about whether certain events are detected or not (floods, droughts, water pollution, etc.). Depending on the context, some example checks on if the model performs as expected could be:
•    Does a model predict a flood in city A while the flood is going to occur in a nearby city B?
•    Does it forecast rainfall in winter while we normally expect rainfall in the region of study during summer?

Can you tell us more about your prior work with remote sensing observations for groundwater?

When you think of groundwater, it is not clear at first thought how it can be measured through satellite observations. Additionally, measuring groundwater with field measurements also has its own challenges. Often, field measurements can be too sparse, perhaps not available for deep aquifers, etc. Nonetheless, groundwater is critical in our water resource planning, with many regions dependent on groundwater for drinking water supplies, irrigation purposes, etc. Fortunately, the GRACE satellite system exists that can detect groundwater variation by detecting changes in gravitational signals caused by it. Processing GRACE data to infer groundwater variations is quite challenging. Nonetheless, it gives snapshots of groundwater conditions over large regions. This information can be crucial in framing water policies.

You are the 2022 Eau Mega Innovation Challenge winner; can you tell us what your project was about and what water-related data management challenge(s) it addressed?

We developed an interactive prototype for a crowdsourcing mobile application called “Aqua: Our water, our concern”. The app envisioned a crowd-based data collection of water quality and quantity situations in any given community. We envisioned its application by both the government as well as civic society organizations to ensure quality and equitable water management practices in a city. A case study was developed for Mexico City. The application prototype could be adapted to different city contexts with some minor tweaks.

In many regions of the world, data is not readily available. This could lead to data asymmetry – meaning that certain groups have more information on a topic than others. Example implications include that rich communities get good water quality supplies while poor communities get infrequent or poor water quality supplies.

How do fair water management practices look like? Can we identify a demographic pattern in how good or bad a water distribution system in a given city is? These are difficult questions we believe should be answered through a public dialogue. Our app envisions enabling such conversations supported by evidence, and hence contributes to democratizing the water management practices in a cities.

As someone who holds leadership roles in youth-led water and climate organisations / networks, what role does the youth have in advocacy for water issues and what would you like to see change in the future?

Currently, I am serving as the Head of the Scientific Committee of the Groundwater Youth Network in a voluntary position. It is obvious that the youth (and the unborn) must face the worst of the climate calamity than the older generations. As such, youth are indispensable stakeholders in the climate dialogue and must have a seat at the table in climate conversations. At the same time, youth are energetic and have the desire and the hunger to make a difference.

Often the political processes are slow. The response to the climate catastrophe has been dictated by the economics and the politics of the world order; and not treated in a way that it should be – as an emergency. Perhaps in our naivety, we the youth are impatient with the pace of developments in the climate response. I strongly believe this energy and hunger and impatience can and should make a big impact in the high-level climate discussions.

At the same time, the young generation is more interconnected than earlier generations. The world feels like a smaller village than it was fifty years ago, thanks to the internet and the general ease in global mobility that technological breakthroughs have enabled. As such, the youth have the capacity to bridge intercultural differences and to look into the world in a more holistic and equitable fashion. The global problems of today could use the global youth to advance solutions from a global perspective.

What would you say are the benefits of young water professionals joining youth-led water and climate organizations / networks?

I have immensely benefited from the youth networks I have been involved in, in terms of professional exposure, professional development, as well as building a youth community focused on climate action. These networks play a big role in elevating the voices of young professionals and university students, to ensure our concerns are heard at the global stage.
Additionally, I must emphasize the interconnectedness these networks enable among the global youth community. The Groundwater Youth Network for instance is a global network of over 1300 people from over 110 countries. I believe, such interconnectedness, fosters a more compassionate, inclusive, and just society in the future.

As a young professional from Nepal, how do you experience the awareness of the potential of space technology and access to space-based data in this country? What are your observations?

The general awareness of young professionals from Nepal in space-borne technologies is limited. However, it has increased manifold in the last decade or so and includes the launch of many university courses focused on geospatial technologies, availability of many training and outreach programs offered by leading institutes in the country, as well as the rise of a few private sector companies focusing on spatial technology and remote sensing over the last few years. The Gurkha earthquake response (2015) was a particular event of importance in such developments. The magnitude of the disaster demanded a large-scale response supported by technology. This, I believe, was met reasonably well. At the same time, the technological developments during and for the earthquake response have been a strong launchpad for many remote sensing organizations in the country.

How do you keep abreast the fast-paced developments (data science, space technologies, water resource management, etc.)? Would you share your secret with other young professionals?

The secret, if I may call one, is to zoom out and zoom in. Especially for young professionals involved in the technological sectors, it is important to keep up with the new developments. One of the ways I like to engage with such developments is by participating in tech events such as hackathons and engaging with the youth community. Hackathons engage the community with the latest technological buzz, while the global youth network brings in a wide spectrum of perspectives. It is important to zoom out to such broader perspectives, engaging with the community, to keep up to date with the rapidly changing technological landscape. At the same time, it is important to zoom in to develop niche expertise in certain domains of your personal interest. Fortunately, I have had the opportunity to work on state-of-the-art technological projects and to learn from amazing peers.

Last but not least, what is your favourite aggregate state of water and why? 

I would say I love liquid water. I love the rivers the liquid water forms, how the rivers flow and transform the land it caresses upon; how it transforms societies and ecosystems through its mere existence.