Stefan Ligtenberg, PhD

Dr. Stefan Ligtenberg is the managing director of Weather Impact.

Stefan graduated in 2009 at Wageningen University in Meteorology and Air Quality. He finished his PhD in 2014 on the field of polar meteorology at Utrecht University. Subsequently he started two postdoctoral positions at Utrecht University, for the last he received an NWO VENI scholarship.

At Weather Impact, Stefan started as consultant and project leader. Since 2018 he gained a lot of experience in project management, he collaborates with different stakeholders and is an expert in translating meteorological weather parameters in messages that fit the local context of a farmer.

Paula Trakoštanec, MSc

Paula holds a MSc Organic Agriculture degree at Wageningen University where she specialized in agroecology and sustainable farming systems. She has practical experience from her internship where she worked on a regenerative agriculture farm in southern Spain, conducting biodiversity research, ecosystem restoration, and working on diverse agriculture techniques. She has been a part of International Association of Students in Agricultural and Related Sciences (IAAS) for five years, which is the biggest association in the world that gathers students with agricultural related fields of study. She gained networking experience and connections from a position in the IAAS World Board. At Weather Impact she works as a business developer.

Mónica Estébanez Camarena, PhD

Mónica holds a BSc in Aerospace Engineering (Technical University of Madrid, Spain), a MPhil in Space Studies (University of Cape Town, South Africa) and a MSc by Research in Space Navigation (University of Cranfield, the UK). Also, she has obtained her PhD in Water Management at the Delft University of Technology. Her research focuses on the modelling of West African rainfall through Earth Observation, Citizen Science and Deep Learning. During her PhD she acquired and led the Schools and Satellites project, that worked with schools and farmers in the north of Ghana to monitor daily rainfall. Her background has given her ample international and multidisciplinary experience, including working in diverse cultural and social environments. She is passionate about global collaboration and co-creation for an impact. Within the Weather Impact team she is involved in business development and capacity building for stakeholders in the agricultural sector.

Joanne Hullegie, MSc

Joanne completed her studies in Soil, Water and Atmosphere at the Wageningen University in 2016, followed by a Master’s degree in Climate Physics from Utrecht University in 2018. She started her professional journey as a consultant at Antea Group at the Air Quality and Nitrogen Deposition departement. There, she gained experience in applied modelling and consultancy. Subsequently she worked from 2022 at TNO in the Climate and Air Quality department as a scienstist and project manager. During her career she gained valuable experience in atmospheric science, serving in various capacities as consultant, scientist and project manager. Currently she leverages her broad expertise and knowledge as a consultant at Weather Impact.

Lorenzo Occelli, MSc

Lorenzo finished his master Climate Physics at the University of Utrecht in 2023 and has a background in  Physics and operational forecasting algorithms. He is a real data expert, and has a strong interest in data modeling and coding. Lorenzo gained experience during his thesis project at Weather Impact, where he studies an algorithm to predict the start and intensity of the rain season in tropical areas. He works at Weather Impact as consultant.

Joep Bosdijk, MSc

Joep gained several relevant experiences during his master Earth and Environment, which he finished in 2023. For his master thesis, he studied the possibility of combining indigenous precipitation forecasts from Ghanaian farmers with meteorological models through machine learning. Next, he did his internship at Weather Impact where he leveraged a deep-learning model to nowcast heavy precipitation over the Netherlands for up to two hours ahead. Currently, he works at weather impact as a consultant.

Arthur Oldeman, PhD

Arthur works at Weather Impact as a consultant. He graduated from Eindhoven University of Technology in 2019 in Chemical Engineering and Applied Physics, which included research internships at KNMI and Deltares. Afterwards, he obtained his PhD degree in 2025 from Utrecht University in the field of Climate Change Specifically, his research focused on El Nino variability and atmospheric dynamics in warm climates in the Earth’s past and in the future. He managed several projects during his PhD, and is experienced in data analysis, programming, and climate modelling. Next to this, Arthur is a strong communicator and is passionate about telling engaging stories on the intersection of climate and (in)justice.

Tamara Lancel

Tamara Lancel works at Weather Impact as Management Assistant and Marketing Coördinator.

She graduated in Hotel & Hospitalitymanagement in 2007 and has a background in the hospitality industry, organizing congresses and events. In her last job she worked as a training coordinator and arranged technical IT trainings for the Benelux and Africa region. Tamara is very strong in planning, coordinating and organizing, and has experience in broad administrative and logistic work. At Weather Impact she supports the management and the team in marketing, HR, finance, administration, acquisition and other organizational tasks, to share our expertise about smart weather solutions.

Eva Sandelowsky

Eva completed her bachelor’s program in Earth Sciences at the Utrecht University and now follows a master in Climate Physics. Her bachelor’s thesis focused on large-scale atmospheric variability in the North-Atlantic region and investigated how patterns differ in a warmer world. From November 2025 onwards, she is working on her combined master’s thesis and internship at Weather Impact. The research is aimed at the course of the rainy season in Ghana, identifying drivers of the monsoon and designing a forecasting model. Parallel to this, Eva also works for the website weer.nl, providing weather forecasts and news articles about weather and climate events. She has a growing interest in science communication and looks forward to applying this passion to her thesis project.

 

Barbara Welling

Barbara completed her bachelor’s degree in Soil, Water and Atmosphere at Wageningen University and is currently pursuing the master’s program Earth & Environment, specialising in meteorology. For her thesis, she used the Weather and Research Forecast (WRF) model to investigate how Arctic extreme weather such as cold air outbreaks, polar lows and cloud streets—is influenced by changes in sea ice and sea surface temperature. Barbara is following her graduation internship at Weather Impact, during which she will use machine learning to refine the resolution of seasonal forecasts. She is eager to apply her meteorological expertise and contribute to innovative solutions for tackling climate change.

Gerrit Hiemstra, MSc, HonDSc

Gerrit is a meteorologist with in-depth experience in the meteorological field. He graduated in 1986 at Wageningen University as Agricultural Engineer, with a specialization in Agricultural Meteorology, followed by a 9-year period as operational weather forecaster in a commercial weather company.

After a brief period as head of the operational weather service at Schiphol Airport he founded the successful commercial weather company WeerOnline, which was sold in 2009.

Gerrit is also the well-known weather presenter of NOS, the national news organisation of the Netherlands, since 1998. In 2014 he founded Weather Impact.

Arnold Lobbrecht, PhD

Arnold graduated in 1986 from Delft University of Technology as Civil Engineer. He gained experience in hydrology, water management and informatics during a 12-years period at a multinational consultancy firm.

After 4 years of research he obtained in 1997 his PhD in operational water management. After that he became part-time professor of hydroinformatics at UNESCO-IHE in Delft, guiding a group of PhD researchers. In 2000 he established HydroLogic, a hydroinformatics company, working on water & ICT projects.

His experience is in decision support systems with focus on flood forecasting, water availability and droughts.
In 2014 he founded Weather Impact.