Spring 2025 SAFL Student Award Ceremony

About the Lorenz G. Straub Award: Established under the Lorenz G. Straub Memorial Fund, this award is given for the most meritorious thesis in hydraulic engineering, ecohydraulics, or related fields. The competition is international, and nominations may be made by any recognized civil and environmental engineering program in the world. Recipients are presented with a Straub Award medal and a monetary gift. Learn more about this award here.

Winner of the Straub Award: Dr. Einara Zahn

Abstact: From Simulations to Real Forests: Understanding Water and Carbon Fluxes in Nature; In this talk, I will explore the partitioning of two key components in the water and carbon cycles -- evapotranspiration (ET) and net ecosystem exchange (NEE) -- which are essential to the functioning of forests and other natural ecosystems. Specifically, I will investigate methods for separating ET and NEE into their soil-based (evaporation and respiration) and plant-based (transpiration and photosynthesis) components. Using advanced simulations called large eddy simulations, I will demonstrate how we can recreate real-world environments to study how turbulence transports CO2 and water vapor between soil and plants. By numerically investigating this transport, we can develop and test partitioning methods that could later be applied in real field experiments. These insights help refine flux quantification, enhancing our ability to predict and understand ecosystem processes. Ultimately, this research supports future studies aimed at understanding how plants respond to various environmental changes, such as increased temperature and CO2 levels, also contributing to more accurate representations of natural ecosystems in climate models.

About the winner: I am a postdoctoral researcher at Princeton University working in the Thermofluids of Urban and Natural Environments Lab with Prof. Elie Bou-Zeid, where I also got my PhD in 2023. My research in the lab has centered on the transport of water vapor, CO2 , and temperature in natural and urban environments. My previous projects focused on improving flux quantification, including novel methods to partition total ecosystem fluxes of CO2  and water vapor into ground and plant contributions, as well as on investigating flux parameterization methods based on the Monin-Obukhov Similarity theory. As a postdoctoral researcher I investigate physical processes within urban canopy models with the goal of improving parameterization for more accurate weather prediction in cities. My research interests include land-atmosphere interactions and atmospheric turbulence, urban microclimate, and hydrometeorology. In addition to field measurements, my work incorporates numerical simulations across different scales using large-eddy simulations and weather prediction models.

About the Heinz G. Stefan Fellowship: This award is given to a University of Minnesota student pursuing graduate studies in later resources engineering who is studying at the St. Anthony Falls Laboratory. Special consideration is given to students involved in environmental hydraulics. Learn more about this award here.

Winner of the Heinz G. Stefan Fellowship: Yuan Li (Advisor: Dr. Judy Yang)

Abstract: Removal of harmful algal cells through clay-algae flocculation;
Cyanobacterial blooms produce toxins that contaminate drinking water and harm aquatic ecosystems. Clay dispersal, a method that flocculates algal cells with clay particles, has been used successfully in East Asia for over 30 years to mitigate blooms but remains untested in Minnesota. This research proposes adapting clay flocculation for local lakes, leveraging preliminary data showing high removal efficiency with laponite clay. To optimize the process, an in-situ visualization system will analyze floc structure and size dynamics during aggregation. The study will also investigate how turbulence influences clay-cell floc formation, a critical factor for real-world application in Minnesota’s variable water conditions. By bridging lab-scale findings with field-relevant turbulence regimes, this work aims to develop a scalable, eco- friendly bloom control strategy. The outcomes could provide Minnesota with a cost-effective, chemically benign solution to cyanobacterial blooms, reducing reliance on algaecides and protecting water quality. This research aligns with global efforts to combat HABs while addressing region-specific challenges in freshwater systems.

About the winner: I am a Ph.D. student in Civil Engineering at the University of Minnesota, working under the guidance of Prof. Judy Yang. Prior to my doctoral studies, I earned both my bachelor’s and master’s degrees in Petroleum Engineering from the China University of Petroleum (Qingdao, China). My research focuses on clay-based technologies to control and mitigate Harmful Algal Blooms (HABs), a critical environmental challenge affecting water quality and ecosystem health. By investigating the interactions between clay particles and algal cells, I aim to develop efficient, eco-friendly strategies for HAB removal that minimize ecological disruption while maximizing scalability for real-world applications.

About the Charles C.S. Song Fellowship:  Established in honor of Professor Charles C.S. Song by a generous group of former graduate students, this fellowship provides monetary support for graduate students at SAFL, particularly for international students.  Learn more about this award here.

Winner of the Charles C.S. Song Fellowship: Anup Vaman Barve (Advisor: Dr. Lian Shen)

Abstract: Demystifying Fog; Fog consists of suspended water droplets or ice crystals near the Earth's surface, reducing near-surface visibility to less than 1 km. Unlike clouds, which form at higher altitudes, fog develops near the surface and is influenced by a complex interplay of dynamic, microphysical, thermodynamic, and surface processes that regulate moisture within the atmospheric boundary layer. These processes govern the formation, evolution, and dissipation of fog, collectively known as the life cycle of fog. Marine fog is a multiscale phenomenon, with length scales spanning several orders of magnitude,  reaching a ratio on the order of 10¹³. Its formation and development are influenced not only by large-scale (synoptic and mesoscale) weather systems but also by intricate small-scale interactions, including microphysical processes and aerosol behavior. Large-eddy simulation (LES) is a powerful tool for capturing small-scale processes such as turbulence, microphysics, and radiation. However, it typically does not account for or poorly represents large-scale dynamics (LSD). To address this limitation, we modify the LES governing equations by introducing additional terms that incorporate LSD effects. Furthermore, we employ both, Lagrangian cloud modeling (LCM) and a bulk cloud modeling approach to analyze the microphysical processes governing fog formation. This combined methodology is applied to simulate advection fog and stratus-lowering fog observed during the Fog and Turbulence Interactions in the Marine Atmosphere (FATIMA) MURI campaign, providing deeper insights into fog dynamics and interactions.

About the winner: I am a Ph.D. student in Mechanical Engineering at the University of Minnesota, working under the guidance of Prof. Lian Shen. I also hold an M. Tech degree in Mechanical Engineering from IIT Madras, India. My research focuses on studying atmospheric boundary layer processes using large-eddy simulation, with a particular emphasis on cloud and fog dynamics. I am especially interested in understanding the physical mechanisms governing these phenomena and improving numerical modeling approaches to better capture their behavior. In my free time, I enjoy playing volleyball and cricket, and I also love exploring new places.