I was born and raised in Rio de Janeiro, Brazil.

Growing up in Rio de Janeiro – a place full of nature, with 30% tropical forest cover in a city of almost 7 million inhabitants, with wild waterfalls and beaches – made me feel very connected to nature, to be very curious, and to care a lot about the earth and the challenges it faces. The person who has most inspired me in my life was my grandfather, Marcos Stern. He was a pharmacist who lived until the age of 92, and during his whole life he worked to develop medicines made from plants. When I was very young, he taught me how to grow a garden, teaching me the secrets of the plants. His eyes shone when he talked about the Amazon, and I grew up hearing stories about this wonderful and magical place, full of plants and animals with all of their colors and sounds.

In 1992, when I was four years, Rio de Janeiro hosted the UN Conference on Environment and Development, known as the ‘Earth Summit’. Of course, I don’t remember it, but in pre-internet times and when travel was quite limited, being close to such an event had a deep impact on a wide range of people. I discovered this impact later on, listening to present-day journalists, academics, teachers, and others. I can say I was raised by a generation that was highly inspired by this event, and this I clearly remember. 

By the age of 8, I was already active protecting biodiversity at my school, and I remember an almost mystic revelation watching a butterfly come out of a cocoon I was protecting. One of my teachers gave me a weekly spot to report to the whole class about my findings on the natural life at school.

My grandfather actually gave a session at the UN Earth Summit with indigenous people, sharing knowledge about medicinal plants. Throughout my childhood, my father would take me at least once a month to one of the science museums in Rio. He also chose a tree by a lake just below our home to be ‘mine’, and I have pictures of myself with this tree all through growing up. I also enjoyed both my summer and winter vacations with a group that used to pick up children from their homes in the morning and spend the whole day hiking in nature. I would wait all semester for these two weeks.

I had always heard about the Weizmann Institute while I was in Brazil, as a very high-level science institute. I remember hearing about it from high school teachers, in the media, and within the Jewish community. After my BSc, I came to Israel and studied at the Arava Institute for Environmental Sciences in Kibbutz Ketura for one semester. The institute is very special, as it gathers together Israelis, Palestinians, and Jordanians to study regional environmental challenges and search for collaborative solutions, since “nature knows no borders”. After getting to know my interests, the academic director of the institute suggested that I try to contact Prof. Dan Yakir at the Weizmann Institute, since his research at the Yatir forest was exactly the kind of work that interested me. I tried to contact him for a few months, with no success. After three months, he suddenly replied and invited me to talk. He offered me a four-month project to calibrate all their sensors, which is something quite boring and something everyone tries to avoid doing. I was passionate about the research and the group, and in addition to giving my whole self to the project, I volunteered for every field measurement. I really saw myself doing this type of research forever.

I told Dan I wanted to become a MSc student in his group, and later a PhD, and then a postdoc. He told me I shouldn’t do this, since I am Brazilian and have already lived in the Amazon. It turns out that Dan had visited the National Institute of Amazon Research in Brazil and was very impressed with what he saw. He told me that the level of instrumentation, the network of big flux towers, and the amount of international cooperation was something I wouldn’t be able to find elsewhere, even at the Weizmann Institute. He recommended that I go back there to do my MSc, and then if I still remembered him, we could talk about a PhD. He introduced me to a highly respected Brazilian scientist whom I didn’t know before, Prof. Paulo Artaxo – who became my MSc supervisor.

Indeed, my MSc was super interesting, and I was involved in very high-level measurements and broad international cooperation. Part of my research was funded by Harvard University, and I went there to present my results. I started talking with one of the Harvard professors about becoming a PhD student with him to continue working with the Amazon, and I even started the registration process. But I couldn’t stop thinking about my experience at the Weizmann Institute and all that I  had dreamt of during those 4 months I had worked there. I decided to contact Dan and do my PhD at Weizmann using a unique mobile laboratory, which opens very broad scientific possibilities and provides highly relevant results. Indeed, I am publishing some of those results now as they have led to very important scientific conclusions.

After I received my PhD, I joined a special program called ‘Mimshak’, a science and policy fellowship aimed at bringing more science-based decision making to the Israeli government, with a focus on sustainability. In this framework, I serve as a scientific advisor to the chief scientist at the Ministry of Agriculture, and I am involved in coordinating research initiatives on a range of topics, including agrivoltaic systems (the dual use of agriculture land for solar energy production), genome editing applications for agriculture, and alternative protein initiatives.

I deeply believe in basic science as an endeavor based on curiosity that aims to understand the natural mechanisms of the earth’s systems. This is a foundational principle of the Weizmann Institute which I strongly agree with. Our type of research shouldn’t be motivated by a final goal or application; I want to understand the mysteries of nature, without being biased by the implications of the conclusions. However, my research and interests lead me to be very worried about our future, and I always search for ways to implement the scientific knowledge we are creating at WIS to guide public policy, and our behavior as a society. Therefore, IES was a very good solution to find a way for me to go beyond my basic science research, and find ways to act together with other PhDs in search for solutions and the means to implement them. For example, we conducted a variety of measurements at the winter pool near Rehovot to provide data for its protection, we volunteered to count tortoises at a nature reserve, we went on several field trips to learn about nature reserves and alternative energy generation by waves, and we prepared research materials for parliament commission debates.

Since sustainability science is by nature very complex and interdisciplinary, I also felt a strong need to go beyond my own research group and department. IES was definitely the best channel for this, and indeed the monthly meetings gave me the connections I was looking for, as well as the opportunity to be exposed to a variety of subjects that added significantly to my experience and knowledge. Moreover, it broadened my experience as a PhD student at WIS and gave me the opportunity to ‘belong’ to other research groups and departments, and have an additional supervisor reference – Prof. Ron Milo, not only for my thesis, but for me as a scientist. Being an IES Fellow enriched my experience as a PhD student by several orders of magnitude.

In November 2023, I will start my appointment as a postdoctoral fellow at the Earth Systems Sciences department at Stanford University, with Prof. Robert Jackson. I will coordinate a network of researchers in Brazil, Peru, French Guiana, and Botswana, aiming to close the research gap in the tropics. My role will consist mainly in assuring all the steps work efficiently, providing the necessary support required by local scientists, due to extremely challenging measurements and research conditions. Whenever necessary, I will calibrate and fix the instruments in the field stations, perform data analysis, post-processing and corrections, and write scientific papers for specific stations. However, my main project is to conduct meta-analyses, combining data from all the stations to broadly understand methane tropical sources and sinks, and the magnitude and partitioning between local elements (wetlands, river seasonal flooding areas, soil, etc.). The success of this project will close a key scientific gap and help guide science-based policy making for a sustainable future.

Rafael’s BSc was at the Earth Sciences department of the Fluminense Federal University in Niteroi, Rio de Janeiro, Brazil, with a focus on Geography. During his BSc, he did a one-year student exchange program at the Amazonas Federal University in Manaus, Amazonas, Brazil. While there, he worked at a lab at the National Institute for Amazon Research, analyzing tree rings for historical climate studies and wood density for biomass carbon estimation. Rafael’s MSc was at the National Institute for Amazon Research, in the Climate and Environment department, where he researched the climate impact of atmospheric particles emitted from forest fires.

At the Weizmann Institute, Rafael did his PhD under the supervision of Prof. Dan Yakir, and his thesis title was “Biogeochemical and biogeophysical effects of different land covers”. The main goal was to understand the impact of land-use changes on the interactions between the surface and the atmosphere. He used a unique mobile laboratory to set up a complete flux station in different land-uses around Israel, including a natural Mediterranean shrubland dominated by oaks, planted pine forest, wheat field, and grazed grassland. His work also included a special project of measuring the impacts of covering the desert with photovoltaic panels. 

The measurements Dan conducted include the exchange of carbon, water vapor, heat, radiation, and other parameters between the surface and the atmosphere, in a technique known as eddy-covariance. Typically, to measure these fluxes around the world, fixed towers are built in one ecosystem. The mobile laboratory at the Weizmann Institute is unique because it allows the comparison of many different ecosystems.

In addition to his research activities, Rafael was selected to represent the Weizmann Institute in South America and presented his research to the Weizmann International Board. Several articles about his work have appeared in the mainstream media, and a documentary is being produced on his research. He has presented at the Brazilian Young Scientists National Conference and at a popular show. Rafael was an invited speaker at the Dead Sea & Arava Science Center conference, and was awarded a finalist prize for best talk at the International Arid Lands Consortium conference in 2021.