Wilco Hazeleger is dean of the Faculty of Geosciences and full professor of Climate System Science at Utrecht University. He is integrally responsible for research, education, and operations of the faculty. The faculty has the ambition to be world leading on research and teaching on the Earth system and sustainability, with a unique combination of expertise in natural and social sciences. It contributes to the Pathways to Sustainability strategic theme. Hazeleger is closely involved in Open Science and applications of AI and data science in sustainability research.

Hazeleger studied meteorology at Wageningen University and Reading University (UK). He obtained his PhD in physical oceanography from Utrecht University in 1999. He then worked at Columbia University (New York) and at the Royal Netherlands Meteorological Institute (KNMI). His research focuses on climate dynamics, climate scenarios, climate adaptation and digitization. He was also professor of Climate Dynamics at Wageningen University. From 2014 to 2019 he was director of the Netherlands eScience Center and focused on the application of digital technology and data science in all scientific domains. In 2019 he was appointed as dean of the Faculty of Geosciences at Utrecht University.

Scientific contributions:

Tales of Future Weather

Society's vulnerability to climate change is evident during extreme weather conditions. Flooding after heavy rainfall, high water and storm damage, drought and heat are clear examples. Extremes are by definition rare and often associated with interactions between large and small-scale weather phenomena that are not well understood. The interaction with socio-economic and ecological processes makes the effects of climate change even more complex. To deal with this complexity, I pioneered in using narratives of climate change, based on vulnerability. Based on a weather extreme that has occurred, interactions and vulnerabilities can be properly mapped out and help to get a good picture of changes in the weather in the future. 

Relevant publications:

Hazeleger, W., van den Hurk, B. J. J. M., Min, E., van Oldenborgh, G. J., Petersen, A. C., Stainforth, D. A., Vasileiadou, E., & Smith, L. A. (2015). Tales of future weather (vol 5, pg 107, 2015). Nature Climate Change, 5(2)

Sillmann, J., Shepherd, T. G., van den Hurk, B., Hazeleger, W., Martius, O., Slingo, J., & Zscheischler, J. (2021). Event-Based Storylines to Address Climate Risk. Earth's Future, 9(2), [e2020EF001783]. https://doi.org/10.1029/2020EF001783

Climate models and digital twins

Climate models describe interactions in the climate system and can simulate the past and future climate. I use weather models in climate research. Weather models are tested daily and simulate weather as accurately and reliably as possible. Current weather models are also coupled with ocean, land, chemistry and sea ice models. This makes these well-tested models suitable for climate studies ('seamless prediction'). I led an international consortium that developed EC-Earth, a climate model based on the leading global weather model, that of the ECMWF. It is one of the leading climate models featuring in IPCC reports now and forms the basis of many projects on climate predictions, projections and climate impact. 

A new development is that of digital twins of the Earth. These are digital replicas that simulate the Earth system as accurately as possible. It consists of simulations and data. With digital twins, the weather and climate and their impact are simulated almost simultaneously with reality. In this way they can contribute to disaster relief, but also to determine the effect of interventions. I am closely involved in the development of the European 'Destination Earth' program, which lays the foundation for both the software (simulation models, artificial intelligence techniques) and the hardware (up to exascale supercomputing) to make this possible. 

Relevant publications:

Bauer, P., Stevens, B., & Hazeleger, W. (2021). A digital twin of Earth for the green transition. Nature Climate Change. https://doi.org/10.1038/s41558-021-00986-y

Hazeleger, W., Wang, X., Severijns, C., Stefanescu, S., Bintanja, R., Sterl, A., Wyser, K., Semmler, T., Yang, S., van den Hurk, B., van Noije, T., van der Linden, E., & van der Wiel, K. (2012). EC-Earth V2.2: description and validation of a new seamless earth system prediction model. Climate Dynamics, 39(11), 2611-2629. https://doi.org/10.1007/s00382-011-1228-5

Workshop:

Organisator Lorentz Center Workshop Digital Twin Earth (Leiden, februari 2023)

Open Science and digitization

It is of paramount importance that knowledge generated in academia is widely shared. This can be in the form of data, software and publications with fellow researchers, but also in the form of public engagement. Hazeleger is committed to a transition to open science through the promotion of open data and software and the development of an Open Knowledge Base for all. Interdisciplinary research can be better shaped through open science.

Hazeleger is co-founder of the AI Lab Sustainability where sustainability researchers, computer scientists and external stakeholders work together on sustainability solutions.

Open science cannot be seen separately from rewards and incenties for scientific staff. The Faculty of Geosciences has implemented the MERIT promotion policy where research, education, leadership, impact and team spirit are valued and developed.

Relevant publications:

De Vos, M. G., Hazeleger, W., Bari, D., Behrens, J., Bendoukha, S., Garcia-marti, I., Van Haren, R., Haupt, S. E., Hut, R., Jansson, F., Mueller, A., Neilley, P., Van Den Oord, G., Pelupessy, I., Ruti, P., Schultz, M. G., & Walton, J. (2020). Open weather and climate science in the digital era. Geoscience Communication, 3(2), 191-201. https://doi.org/10.5194/gc-3-191-2020

Ruti, P. M., Tarasova, O., Keller, J. H., Carmichael, G., Hov, Ø., Jones, S. C., Terblanche, D., Anderson-Lefale, C., Barros, A. P., Bauer, P., Bouchet, V., Brasseur, G., Brunet, G., DeCola, P., Dike, V., Kane, M. D., Gan, C., Gurney, K. R., Hamburg, S., ... Yamaji, M. (2020). Advancing research for seamless earth system prediction. Bulletin of the American Meteorological Society, 101(1), E23-E35. https://doi.org/10.1175/BAMS-D-17-0302.1

I was lead convener of a Lorentz workshop on Digital Twins of the Earth that perfectly shows my research interests.