How do you personally and professionally relate to water and/or space technologies?

I have been monitoring Patagonian glaciers with satellite images for almost 20 years, as part of my work in a research group on space technologies applied to the environment at the National Technological University (UTN) in Argentina. These glaciers are located in the south Argentinean territory, at the border with Chile. Luckily, I had the chance to explore a great part of the area during many visits.  Since I live far from the Patagonian glaciers, in Buenos Aires, I shared field campaigns with other students and professionals where we learned about the evolution of glaciers dynamics, environmental challenges and about the people affected by these dramatic changes. 

I started learning about space technology applied to environmental monitoring as a fellow while I was studying aeronautical engineering. I have always been curious about space exploration, and I have found how sensors from space can help improve life on Earth.

What motivated your focus on glacier monitoring, particularly in the Patagonian region? What significance does this research hold for environmental conservation?

I started working as a fellow in the Synthetic Aperture Radar (SAR) research group during my studies in Engineering. Thanks to the director of the group, I was lucky to meet one of the first professionals and explorers who documented the names, locations and conditions of almost all glaciers within Los Glaciares National Park and its surroundings. Eng. Mario Bertone, wrote the first inventory of that group of glaciers, which today serves as an invaluable work forming a basis for the glaciers’ monitoring. 

Patagonian glaciers show a remarkable retreat, affecting the landscape, the dynamic of the lakes and rivers, and consequently, touristic activities. The photographs and locations of glaciers that Bertone gathered are used as a reference for retreat measurements. We have noticed that many of the small mountain glaciers that appear in his book are now gone.

This changing landscape directly affects the main income of the population: tourism. El Calafate has more than 25,000 inhabitants and relies on many different touristic activities, such as boat tripping, ice trekking on glaciers and regular trekking, hiking, climbing, horse riding and also kayaking around glaciers. However, due to ice melting and breaking, ice trekking tours were severely affected, and some were cancelled. Boat tours are threatened by huge iceberg calving and occasional landslides. 

Could you share your journey from being a fellow in the Synthetic Aperture Radar research group to becoming its Director? How has your background in Aeronautical/Aerospace Engineering influenced your work in remote sensing and environmental monitoring?

It was a long journey! I applied for a UTN fellowship 20 years ago, since I needed economical support to continue my studies. I chose the SAR research group because of a colleague’s referral. Having met Eng. Jorge Gari, former Director and founder of the group, he trained me in remote sensing. He was also the chief of the Remote Sensing Centre of the Argentinian Air Force, where I have been working since 2014.  For almost ten years, I continued working closely and ad honorem on the projects conducted by the research group. In 2023 Eng. Gari retired and I became the new Director of the group. Although Aeronautical Engineering is focused on plane design and manufacturing, the mathematical and physical basis covered during my degree in Engineering allowed me to deeply understand satellite image analysis and processing.

Can you share about the methodologies and technologies you employ for glacier monitoring, including the role of SAR, optical imagery, LiDAR, and altimetric data?

For multi-temporal glacier monitoring we make use of freely available optical imagery from satellites, such as the very first Landsat platforms from 1976 to current Landsat 8 and 9, European Space Agency (ESA) Sentinel 2 A and B, and Planet. 

Since the area is nearly always covered by clouds, we had to learn how to handle SAR data. Two of the most important characteristics of SAR technology is that it is almost not affected by the weather and that it can gather data at night. Therefore, we also work with ERS, RADARSAT, COSMO SKYMED, ALOS PALSAR, Sentinel 1 and SAOCOM missions. SAR images help us measure glacier boundaries as well as classify different ice structures, snow, debris and water on glaciers. We also use some special pairs of SAR images to create Digital Elevation Models (DEMs) and measure ice flow velocity. 

DEMs are used for mass balance calculations. We measure elevation changes over time in ice and snow from SRTM DEM, ASTER AST14DEM, ALOS PALSAR DEM, TanDEM-X and from LIDAR data of ICESat missions. In some special cases, we had access to topographic maps surveyed by the National Institute of Geography in 1982. Since the area of interest is vast and inaccessible, there is not much historical information on the heights of the glaciers.

Vector data from Global Land Ice Measurements from Space (GLIMS) repositories helps us delimit glacier boundaries, which are particularly difficult to distinguish, especially in the upper part of glaciers located within the Ice Field.

Moreover, we compare mass balance results and superficial retreat measurements with meteorological data from National Aeronautics and Space Administration (NASA) Prediction of Worldwide Energy Resources (POWER) and Goddard Earth Sciences (GES), Data and Information Services Center (DISC) projects.

Do you, and if so, how do you relate your research results to climate change scenarios? If thematically relevant, will it be important that researchers link their work to the various Climate change scenarios? How can one best do that, and what does that mean for researchers, since we talk about a variety of potential future scenarios? 

The shrinking and melting of glaciers in the National Park and its surroundings are in direct relationship with ongoing global warming. Glaciers are located on the western side of the country throughout the mountain range of the Los Andes and are responsible for feeding huge lakes with melt water. This melt water converges into the Santa Cruz River and flows more than 250 km crossing arid Patagonia to finally end in the Atlantic Ocean. It provides drinking water and water for irrigation agriculture to the entire basin. There have been no noticeable changes in the river flow rates so far. However, the population and the ecosystems located all along the river course will be affected once the river flow decreases in the future.

The Intergovernmental Panel on Climate Change (IPCC) is the leading international body in the context of the United Nations / the World Meteorological Organisation in charge of assessing science related to climate change. In recent reports, IPCC announced that melting ice sheets and glaciers are now the dominant source of global mean sea level rise, affecting coastal regions and their large populations and economies. We presented glacier mass balance measurements that indicated a contribution to sea level rise.

I think, intergovernmental organizations such as the IPCC today have a crucial responsibility in gathering data and reports from scientific communities around the world in an orderly manner. There are local IPCC groups in each country who gather and evaluate this important information.  As researchers, linking our work to different scenarios is not only necessary but significantly valuable. For this connection to acquire valuable relevance, it is essential to share information and achieve multidisciplinary work. One of the fundamental elements to consider regarding the objectives of the research is that they should be focused on addressing the problems related to potential future scenarios, as well as providing possible solutions to them.

In your experience, how do Light Detection and Ranging (LiDAR) and altimetric data contribute to elevation estimates and digital elevation models in glacier monitoring? Could you elaborate on any challenges you've faced in utilizing these technologies? 

We can use optical and SAR images to measure superficial changes in glaciers. To assess their volume, however, we need elevation data. We have noticed that the visual stability of glacier fronts and surfaces observed in satellite images is not enough evidence to monitor the condition of a glacier, and it becomes necessary to perform volumetric analysis. 

Ideally, mass balance estimations are conducted in situ by placing a network of stakes and pits on the glacier surface and measuring the change in surface level and snow/ice density. To cover a whole glacial cycle, this is performed on an annual basis. Nonetheless, in remote areas like the Patagonian Andes and with scarce funding, mass balance is still estimated indirectly, measuring elevation changes over time from various DEMs, LiDAR point clouds and altimetric data from space.

Unfortunately, there is only a small amount of freely available DEMs and elevation measurements of the area, leading to sparse mass balance results over time. The main challenge I face when trying to evaluate glacier behavior is getting elevation data with a higher temporal resolution.

Your work involves monitoring areas under the Department of Defense and the National Parks Administration. How do you navigate the intersection of environmental monitoring and Defense interests in your projects? 

In 2007, the Ministry of Defense and the National Parks Administration of Argentina signed a Framework Cooperation Agreement with the main objective to jointly develop active policies for biodiversity conservation. To date, 18 Defense Natural Reserves have been established, which represents an innovative conservation model in Latin America. These military properties are managed from a conservationist perspective without affecting their institutional dependency or their specific function, such as training, maneuvers or instruction fields. 

I have monitored three of these natural reserves by means of remote sensing techniques. The first one is in the Buenos Aires province. It is called Mar Chiquita Albufera and is part of an UNESCO Biosphere Reserve. The second is located in the subtropical rainforest near Iguazú waterfalls. And the last one is part of the Córdoba Mountain Range located in the central part of the country. This ongoing research is conducted together with researchers from the Remote Sensing Centre of the Air Force. 

What role do GIS analyses play in your research projects, particularly in change detection analysis and forest classification? Can you share any insights into the significance of spatial analysis in environmental monitoring? 

Until recently, I used GIS software to output thematic maps and results from my analyses graphically. However, I currently use GIS as an analysis tool, for both raster and vector file processing. It is particularly useful for delimiting glacier boundaries and the accumulation and ablation zones. Regarding raster analysis, I use some image correlation functions for multi-sensor studies. Additionally, new plugins are constantly being developed to meet all types of analysis needs. 

Moreover, having updated and quality geographic information derived from satellite data contributes to a regular monitoring of the operational activities performed by the Defense in the reserves.

Which natural phenomena occurring in your research area/country/in Latin America or elsewhere, do you anticipate to have an impact on the glaciers in your region? 

The El Niño Southern Oscillation (ENSO) is a large-scale natural climate variation that leads to fluctuations in temperature and precipitation across the regions where it is distributed. During La Niña phases, precipitation decreases in Patagonia, making winters drier, which can cause a decrease in the amount of snow accumulated in glaciers, thus leading to negative volume balance over the year. In turn, a decrease in temperatures below the average can be observed. 

During El Niño events, on the other hand, an increase in precipitation occurs which results in a greater amount of snow during the cold season and its subsequent accumulation, resulting in a positive balance throughout the hydrological cycle. 

Both phenomena have intensified over the last five years. One main objective of our research is to find a relationship between these events and the mass balance of glaciers.

As a university lecturer, how do you integrate your research experiences into your teaching methodologies? What advice do you offer students interested in pursuing careers in remote sensing and environmental monitoring? 

I started teaching Remote Sensing at the Universidad Nacional de Luján two years ago. On my first day, I showed the students how to operate a very well-known freely available GIS software. They had to perform a visual analysis of an optical image printed on a piece of paper and delimit the main areas with a marker. I offered them to choose between the printed image and the software, or to do both, to draw the polygons, lines and points to finally perform a preliminary land cover classification. They decided to use both techniques because they found both very instructive, and we finally shared the pros and cons.  

After that very first day, I realized that everything I learn during research can be used as teaching instruments to improve the dynamic of the classroom, from pure physics to image processing. 

How do you stay updated with the latest developments in remote sensing and GIS technologies? Are there specific conferences, journals, or online resources you find particularly valuable?

Nowadays, AI and remote sensing technologies go hand in hand. AI has been deeply transforming the way we process spatial information. Sometimes the changes pose challenges. I occasionally check posts on LinkedIn from professionals who are up to date with the latest advancements, like Falah Fakhri, Qiusheng Wu, Milan Jasonov, Spatial Thoughts and others, and of course, the main space agencies of the world. I also subscribed to newsletters from space agencies, government institutions and some private actors that offer training programs and organize webinars. I participate in national and international conferences related to Geography and     Climate Change and encourage the students and members of the research group to be part of them as well.

What advice would you give to early-career professionals aspiring to specialize in remote sensing and environmental monitoring, based on your own career trajectory and experiences?

Remote sensing can have a large number of applications. It is certainly a super interesting science and can be approached in many ways. For instance, the images recorded by a satellite provide very useful information regarding geological mapping where it is necessary to cover a large area. They can be used for establishing differences in soils and rocks. They are also important in the study of dynamic phenomena, such as coastal sedimentation processes, volcanic eruptions, erosion and desertification processes, together with monitoring of geo-environmental changes such as glacier retreat. As a professional, you can make it very profitable if you relate your work with the agribusiness industry or the mining sector, for example. I have chosen an environmental and not so commercially enriching approach related to research and teaching because it aligns with my ideologies. 

In my case, I learned about geo-sciences alongside my undergraduate degree. Thus, it is important to mention that you can learn remote sensing no matter your degree or underlying education, though most people come from Earth sciences careers. 

Looking ahead, what are your goals and aspirations in the field of remote sensing and environmental monitoring? Are there any specific research areas or projects you hope to explore further?

I would love to apply all my knowledge and expertise in remote sensing to other planets and their moons, imagine if we could find and research on water on other planets!

What do you need to innovate?

I sometimes find it hard to keep up with such a huge amount of new programming tools applied to remote sensing. When I started working in this area, around 10 years ago, just a few freely available software programmes were available for image processing. Nowadays, everything can be developed with some lines of code. Therefore, learning programming languages like python and new methodologies is something I consistently pursue.

What is your favourite aggregate state of water?

Although I love glaciers, I prefer the liquid warm water of a thermal bath ;)