![Forecasting storms using soap bubbles. The color code indicates the intensity of the turbulence [courtesy of CNRS]](https://www.hayadan.org.il/images/content3/2014/03/soaps-500x348.jpg "Forecasting storms using soap bubbles. The color code indicates the intensity of the turbulence [courtesy of CNRS]")
Can soap bubbles be used to predict the strength of terrible wind storms such as hurricanes and cyclones? Although it sounds completely improbable, physicists from the National Center for Scientific Research in France (CNRS) performed a particularly innovative experiment: they used soap bubbles to build a model of the flow in the atmosphere. An in-depth study of the movement rates of the bubble eddies allowed scientists to obtain a correlation that accurately describes the evolution of the eddies' intensity, providing a simple model for predicting tropical storms.
Predicting the power or strength of the wind during tropical storms such as cyclones, typhoons and hurricanes is an important objective in the field of meteorology - the lives of hundreds of thousands of people may depend on it. At the same time, despite recent developments, such predictions still remain challenging since they involve many factors related to the level of complexity of giant eddies and their interactions with the environment.
The researchers performed flow simulations in soap bubbles, which simulate the curved shape of the atmosphere and which constitute the most faithful approximation to a simple model of flows in the atmosphere. The experiment allowed the researchers to obtain eddies similar to tropical cyclone-type storms that start off weak and increase over time. Following this build-up phase, the vortex reaches its maximum strength before it begins to fade.
An in-depth study of the movement rates of the bubble eddies allowed scientists to obtain a correlation that accurately describes the evolution of the eddies' intensity. For example, this correlation can be used to determine the maximum intensity of the vortex and the time required to reach this intensity, based on the calculated development.
This prediction can begin around 50 hours after the formation of the vortex, a time corresponding to a quarter of the life time of the storm, when the wind gathers its high speed. The researchers continued from this stage and tried to show that their results can be applied to real tropical cyclones. Using data from about 150 tropical cyclones that occurred in the Pacific and Atlantic oceans, the researchers showed that the correlation does exist for such low pressure systems. This study provides a simple model that can help meteorologists better predict the strength of tropical cyclones in the future.
