Extreme heat waves and heavy rainfall are increasing in intensity on a global scale, trends which will continue with future global warming. Summer, with most biological and agricultural production, is probably the season when changes in extremes will have the most-severe impacts on humanity. Summer extremes are particularly devastating when they persist for several days: Many consecutive hot-and-dry days causing harvest failure, or stagnating wet extremes causing flooding. Despite this importance, persistence of extreme summer weather has largely been neglected by the climate science community. What maintains stagnating summer weather? Do climate models capture persistence and the underlying processes accurately? What is the role of global warming? Persistence is linked to sea-surface temperature, soil moisture and atmospheric circulation which are expected to change with future warming but the uncertainties are large. The proposed research fills this knowledge gap. I will study mid-latitude summer circulation and its influence on weather persistence focusing on the most high-impact, persistent summer extremes. The project innovatively combines novel methods from disciplines which historically evolved largely independently: (1) Machine learning guided by physical theory and (2) climate modeling experiments using state-of-the-art global Numerical Weather Prediction models. I will quantify persistence of summer extremes and their local and remote drivers in past, present and future climates, focusing on Western Europe and eastern U.S., i.e. two major population centers critical for global food production. In recent publications, I have reported a pronounced weakening of boreal summer circulation since 1979 and hypothesized that this leads to more-persistent, and therefore more-extreme, summer weather conditions. This overarching hypothesis will be tested, using the described methods, in observations and modeled data at different warming levels. This work will reduce societal risks from future summer extremes by improving existing forecasts and developing novel early warning systems based upon optimal empirical prediction methods.

Based on a design-oriented, co-learning living labs approach, this project aims to co-develop inter- and trans-disciplinary insights and tools that support farmers, Waterboards, Provincial Governments and other public and private stakeholders in the Netherlands in the process of upscaling private and collective water storage for robust agricultural systems. It does so by bringing together innovative insights from agricultural sciences, hydrology, law and governance studies with knowledge from day-to-day practices on the ground. It does so by using diverse participatory and iterative modelling and visualisation tools for multiscale scenario development to develop innovation pathways for agricultural and governance innovation.

Accelerated sea-level rise (SLR) seriously threatens coastal areas globally. Sand nourishments – the addition of sand to increase the beach volume – are potentially a key method to sustainably adapt to accelerated SLR and keep the low-lying hinterland protected against coastal flooding. The SOURCE project will deliver the scientific knowledge, models and design tools to develop and evaluate nourishment strategies in a multi-stakeholder co-creation process. These carefully planned sand nourishments will create the required and desired resilient and dynamic multifunctional coastal landscapes of the future.

The massive transition towards renewables combined with more frequent climate extremes is strongly increasing energy market volatility. Reliable weather forecasts weeks to months ahead are urgently needed to support stakeholders in the energy sector to optimally plan production, maintenance, resources, and distribution. Our Artificial Intelligence based forecasts outcompete those of operational systems and have the potential to disrupt the modus operandi in the energy sector. Forecast products for the energy sector would support the transition to resilient and sustainable energy systems by 1) keeping energy affordable, (2) optimizing the share of renewables and (3) fostering energy security.

Sea-level rise, land subsidence, extreme rain, and drought: climate change brings new risks for real estate and infrastructure, especially in urbanized, low-lying deltas. Our cities are valuable assets, as living environments, economic drivers and investment assets. Adaptation to a changing climate is crucial to retain these diverse values, especially for the most vulnerable. Trans-disciplinary knowledge for climate resilient urban investment and development is crucially needed. In this project, we bring investors, planners and managers of real estate and infrastructure, and academics from relevant disciplines together to co-develop an integrative climate governance strategy for a resilient Dutch delta.