New research sheds light on the spread of viruses in air and water

New and more precise predictive models have been developed that could potentially help us respond earlier to infectious diseases such as COVID-19.

The researchers, from the University of California, Santa Barbara, the University of Iceland, and the University of Oslo, have created a model that illustrates how particles disperse in flow—either in air or water. This understanding is crucial for meteorology, oceanography, engineering, and not least medicine. One of the model’s authors is Björn Birnir, a scientist at UC Santa Barbara and visiting professor at the University of Iceland.

“We are deepening our understanding of fluid dynamics,” says Björn Birnir. “This is not just a theoretical advancement; it could have real-world implications for how we respond to weather, pollution, and even infectious disease.”
Instead of observing flow from a fixed point, as is common, the researchers used a so-called Lagrangian approach, which involves following the flow itself and tracking how particles move, mix, and spread.

Significant impact on understanding cloud formation, wind development, and pathogen dispersion

The results show that particles follow specific patterns that can be predicted using the new model. This has various practical applications, such as:

• improving weather forecasts through more accurate descriptions of cloud formation and wind,
• better predicting the spread of pollution in the ocean or atmosphere,
• understanding how aerosols containing pathogens, such as viruses, are transmitted between people.

A smart method for seeing the bigger picture

To better explain the Lagrangian method, the scientist essentially travels with the flow instead of standing still and observing the flow as it passes by (as is typical in traditional measurement, known as the Eulerian approach). They “fly” with the water or air particles and observe how they move, mix, and spread.

It’s like jumping into a boat on a river and watching how branches, leaves, and water droplets travel downstream, rather than standing on the bank and viewing everything from one fixed point.

The advantage is a more accurate picture of how particles or substances travel with the flow, essential for understanding dispersion, mixing, and flow development.

Supercomputers were used to capture the immense complexity of particle movement within flows.

Björn says the research is based on calculations by collaborators at the University of Rome. It provides valuable insight into Lagrangian fluid dynamics, which can influence oceanography, engineering, and medicine.

You can read the full article here, co-authored by Luiza Angheluta from the University of Oslo.