Two months ago, from October 14 to 18, Wageningen University and Research (WUR) hosted the nextGEMS Hazard Hackathon. Nearly 80 participants from 17 countries across three continents traveled to the Netherlands for this unique event.

A New Approach to Collaboration

Unlike previous hackathons that divided participants based on the nextGEMS working groups Storms and Land, Storms and Oceans, Storms and Radiation, and Storms and Society, this event took a fresh approach. Participants were organized into challenge groups focused on specific hazard-related topics, such as efficient data handling, the energy sector, fire weather, and extreme precipitation and temperature. These groups delivered remarkable insights and visualizations. Take a look for yourself:

Highlights of the Challenges

Efficient Data Handling Challenge

Led by Lukas Brunner and Olivia Martius, this group focused on providing global extreme indices for the HEALPix zoom level 9. They developed highly detailed plots, such as a comparison of surface temperature fields from the ICON and IFS models. One visualization revealed significant discrepancies of the annual maximum temperatures (txx) between the two models that were especially pronounced in North America and Australia. These results are likely due to differences in how the models simulate land-atmosphere interactions.

Energy Production Challenge

Coordinated by Menno Veerman and Edgar Dolores-Tesillos, this team analyzed weather-dependent energy production, in particular solar and wind energy. They explored the spatial patterns of each of these around the world and found that there is more capacity to produce wind energy over the oceans than on land, and a larger solar energy capacity in regions closer to the equator. In a case study approach, the team also discovered distinct spatial patterns of solar and wind energy production across Spain. Additionally, the researchers progressed a trend analysis for the region of Spain, to assess how the energy production capacity might change over time.

Fire Weather Challenge

The team led by Ralf Hand and Chiel van Heerwaarden focused on evaluating the potential of nextGEMS models to simulate realistic fire-prone weather conditions. They also sought to identify the factors driving potential changes in wildfire risk in the future. During their work, the team successfully modeled fire weather indices (FWI) as used by DWD, and also observed that humidity trends remain constant over time. However, they noted differences in the calculations produced by the IFS and ICON models, which require further investigation. Following this hackathon, the scientists plan to rerun these calculations using higher-resolution data to better understand how coarse versus high-resolution data impacts the results.

Extreme Precipitation and Temperature Challenge

Jonathan Wille, Jasper Denissen, and Birgit Suetzl led the extreme precipitation and temperatures and urban heat challenge. This group examined the simulation of temperature and precipitation extremes at different levels, from the global to the local scale. The participants explored various topics within this broader frame, including the visualization of urban heat extremes, future changes in extreme precipitation behavior, and the connection between precipitation extremes and river runoff in alpine regions.  They found that changes in the frequency of heavy precipitation events depend on the rarity of the event and the modeling approach. For instance, a 1-in-3-year event occurs 5% more frequently in IFS simulations and 20% more frequently in ICON simulations. The researchers also discovered that these changes vary by the region in which the precipitation events occur, with heavy precipitation events in the Northern Hemisphere becoming more frequent at locations further away from the equator.

Engaging Side Events and Workshops

In addition to working on their group challenges, participants engaged in several enriching side events. Paolo Davini and Matteo Nurisso from CNR-ISAC introduced the model evaluation framework AQUA, developed as part of the Destination Earth initiative (DestinE). During a workshop on energy storylines conducted by Eulàlia Baulenas and Dragana Bojovic, participants debated which nextGEMS data would be relevant for energy industry stakeholders and how the project could help them make more informed decisions. Experts like Nuria Sanchez from Iberdrola and Hester Biemans from WUR shared captivating insights on topics such as renewable energy and food security.

The Role of Hackathons and Collaboration in Climate Research

On the final day, the Storms and Society working group presented their ongoing efforts in knowledge co-production and communication strategies. Their outputs aim to bridge research and policy-making through storylines, policy briefs, and accessible Science Explainers that communicate complex research to the public in simple terms.

Hackathons like this Hazard Hackathon foster collaboration, innovation, and knowledge sharing, as emphasized by Bjorn Stevens, Director of the Max Planck Institute for Meteorology. Stevens highlighted how nextGEMS contributes to broader climate modeling projects, including EERIE, WarmWorld, and DestinE. Thanks to the efforts of the nextGEMS community, DestinE successfully launched its system in June 2023, with its data now accessible to the nextGEMS community and the wider academic community via a newly released DestinE platform.

Inclusive Initiatives at the Event

However, not only scientific input and outcomes were at the focus of the Hazard Hackathon. The organizers also prioritized inclusivity by offering pronoun stickers for all attendees and rainbow lanyards for LGBTQIA2S+ community members and allies. These thoughtful gestures aimed to foster respect and acceptance for the diverse gender identities and sexual orientations within the nextGEMS community. For further reading on supporting the Queer community, attendees were encouraged to consult the HRC report on Being an LGBTQ+ Ally or explore resources provided by the EGU Pride group, which supports Queer individuals in geosciences and their allies.

The Future of nextGEMS: Transitioning Beyond the Project

Following three years of intensive knowledge creation, hacking, and collaboration, the nextGEMS project is now transitioning into its final phase. During the recent gathering, Bjorn Stevens initiated a discussion about the future of the nextGEMS community and its potential evolution beyond the project’s official timeline. As part of this dialogue, he announced an unprecedented event: the World Climate Research Programme Global KM-scale Hackathon.

This groundbreaking global hackathon is scheduled to take place from May 12–17, 2025, and will be hosted by multiple climate modeling institutes across the globe, including locations in Australia, Brazil, Argentina, China, Europe, India, Japan, North America, and South Africa. This unique, multi-continental approach highlights the collaborative and inclusive spirit of the climate research community.

To stay updated on the nextGEMS project and future events, including the final nextGEMS Hackathon, visit our news section and follow our social media channels.

The sixth and final hackathon of the nextGEMS journey is set to take place from Tuesday, March 25th to Friday, March 28th, 2025. We’re thrilled to invite our vibrant community and all climate modeling enthusiasts to come together for this special event.

This time, we’re heading to the captivating capital of Sweden: Stockholm. Our venue? None other than the Swedish Museum of Natural History, the largest museum in the country, providing the perfect scenery for four days of creativity, collaboration, and innovation.

As we approach the conclusion of our project in 2025, this hackathon will be a bittersweet celebration of everything we’ve accomplished together. 

Expect engaging interactive activities, opportunities to connect and network, and of course, plenty of exciting hacking sessions to tackle challenges in climate modeling.

Stay tuned for updates on our official channels, including Mastodon and LinkedIn.

As part of the nextGEMS production stage for our high-resolution Earth system simulations, a new hackathon edition has been launched. The fifth nextGEMS hackathon is currently taking place in the central Netherlands, in the city of Wageningen, renowned for its university and vibrant student life.

From October 14th to 18th, 2024, more than 80 scientists, researchers, students, and other representatives from across Europe, North America and East Asia gather for the „Hazard Hackathon“ at Wageningen University. Here, they can collaborate, network, and tackle pressing challenges related to fire weather, precipitation, urban heat extremes, and more.

On the first day, Chiel Van Heerwaarden, a researcher and co-organizer from Wageningen University, kicked off the event with a welcoming speech and general information for the week to come. Following, scientists Dyvia Praturi from the Max Planck Institute for Meteorology and Xabier Pedruzo from the European Centre for Medium-Range Weather Forecasts (ECMWF) provided updates on the available ICON and IFS Earth system models‘ simulations.

Praturi encouraged participants to seek guidance and answers to their questions about the Easy Gems platform, while Pedruzo highlighted a recently published research paper detailing the advancements in IFS simulations.

During the opening session, Jasper Denissen from ECMWF introduced the audience to the Catchment-based Macro-scale Floodplain (Ca-Ma-Flood) model. He explained how its hydrological forecasts are being used in nextGEMS simulations and mentioned some of the Ca-Ma-Flood output variables that participants can work with, such as river discharge and flooded fractions.

Before the first day concluded with an exciting ice-breaker session that included some delicious local finger food and a round of pool and table tennis, Edgar Dolores-Testillos from the University of Bern presented the innovative structure of this hackathon. Unlike in the previous events, this time participants will have the opportunity to choose from five defined challenges: efficient data handling, fire weather, precipitation and temperature extremes and urban heat, energy production, and a „wild card“ challenge encompassing topics like tropical cyclones and extreme precipitation. Nevertheless, he emphasized that participants are also free to pursue their own or collective interests during the upcoming days of the hacking marathon.

– Junhong Lee, and Cathy Hohenegger

To date, numerous studies have explored the connection between water stored in the soil, also called soil moisture, and precipitation. Using coarse-resolution global climate models, these studies have consistently found a positive feedback between soil moisture and precipitation. In other words, wet soils favor rain. And as rain itself wets the soil, a positive feedback between rain and soil moisture is maintained: soil moisture matters!

In a pioneer study, Hohenegger et al. (2009), looked for the first time at this same soil moisture-precipitation feedback in km-scale simulations conducted over the Alpine region and found the opposite result: dry soils favor rain. Hohenegger et al. delved into the reasons behind these conflicting findings and related them to how different models represent convection. Coarse-resolution models rely on simplified statistical representations, known as parametrization, to describe convective processes. In contrast, kilometer-scale models represent convection explicitly by solving the underlying fluid dynamical equation (a mathematical description that explain how liquids and gases move and behave). Yet, due to computational constraints, the study of Hohenegger et al. (2009) could only simulate the climate over a small region. It could not be excluded that the lateral boundary conditions (LBCs) required at the border of that region, which are taken from a coarse-resolution global model, may spuriously affect the sign of the soil moisture-precipitation feedback (What are LBCs? Read: Davies, 2013).

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Building on these insights, Lee and Hohenegger, in their 2024 study, sought to overcome the limitations of Hohenegger et al. (2009) and following studies. They employed a global, coupled climate model with explicit convection and a 5km resolution. Using the storm-resolving version of the ICON model allowed Lee and Hohenegger to represent the feedback more accurately than coarse-resolution models by representing convection explicitly, while allowing the large-scale circulation to freely evolve and interact with convection by using a global domain (a simulation over the full Earth). Their remarkable findings suggest that precipitation is less influenced by soil moisture and evapotranspiration (the combined effect of evaporation, the transport of moisture from the earth surface directly to the air, and transpiration, the transport of moisture from the soil to the air via plants) than coarse-resolution climate models have led us to believe.

The study revealed several key points:

1. The feedback between soil moisture and precipitation is weaker and more negative than coarse-resolution models suggest. The presence of a negative feedback indicates that drier soils are favorable for precipitation and that soil moisture is not so important for precipitation.
2. The feedback between evapotranspiration and precipitation is also weaker. In contrast to the coarse-resolution model, precipitation does not consistently increase with evapotranspiration in the storm-resolving model.

When compared with observational data, the global, coupled storm-resolving model provided more accurate representations of the strength of the correlation between soil moisture and precipitation for over 80% of the locations, suggesting that this type of model may be better suited for global precipitation modeling.

These findings indicate that coarse-resolution climate models may overestimate the role of land cover change and of the land surface in general for precipitation. They challenge our understanding of climate over land and may indicate that precipitation patterns may be more robust than previously thought.

For more on this topic, find the entire publication here.

References:

Hohenegger, C., Brockhaus, P., Bretherton, C. S., & Schär, C. (2009). The Soil Moisture–Precipitation Feedback in Simulations with Explicit and Parameterized Convection. Journal of Climate, 22(19), 5003-5020. DOI: 10.1175/2009JCLI2604.1

Lee, J. & Hohenegger, C. (2024). Weaker land–atmosphere coupling in global storm-resolving simulation. Proceedings of the National Academy of Sciences (PNAS), 21(12). DOI: 10.1073/pnas.2314265121

Rainfall patterns around the tropics, the regions encircling the Earth’s equator, are crucial for understanding global water and energy cycles. These tropical rain belts migrate seasonally, following the sun’s path north and south. Scientists have long struggled to accurately model these complex dynamics using traditional climate models.

The study, „Learning by Doing: Seasonal and Diurnal Features of Tropical Precipitation in a Global-Coupled Storm-Resolving Model“ by Hans Segura and colleagues, offers a breakthrough. Their research utilizes the new generation of high-resolution simulations that nextGEMS is developing, which incorporate both atmospheric and oceanic interactions. This level of detail allows for the explicit representation of convection (the process by which warm, moist air rises and cools, forming clouds and precipitation) and mesoscale ocean eddies (large, swirling currents).

In this research video, produced by Latest Thinking, researcher Hans Segura highlights the promising results. On one hand, the simulations accurately capture the seasonal migration of the rainbelt over land, including its movement north and south, east and west, and expansion during summer. This is particularly true for the eastern Pacific and Atlantic regions. However, Segura clarifies that the model struggles to replicate these patterns over the Eastern Hemisphere’s oceans. The researchers suggest this discrepancy might be due to limitations in representing sea surface temperature patterns in these areas. In that sense, Segura points out that the model needs to be further developed, in addition to theoretical work and observations to understand the mechanisms influencing sea surface temperature.

Hans Segura is currently pursuing post doctoral research in the Climate Physics department of the Max Planck Institute for Meteorology. Previously, he completed his doctorate at Université Grenoble Alpes  and conducted research at the Geophysics Institute of Peru. His research interests include precipitation-convection, clouds, and tropical climatology.