In the realm of energy journalism, understanding the factors that influence tropical cyclones is crucial, as these powerful storms can significantly impact energy infrastructure and operations. Researchers, including Hao Fu, have been delving into the intricacies of tropical cyclone (TC) formation, particularly focusing on the role of cold pools in determining the size of TC embryos. Fu is an atmospheric scientist whose work has been published in the journal Geophysical Research Letters.
Cold pools, which are pockets of cold air that form beneath thunderstorms, play a pivotal role in the development of tropical cyclones. Recent studies have highlighted that both cold pools and planetary rotation affect the size of TC embryos, with the former increasing and the latter decreasing the size. While the effect of planetary rotation has been well-studied using a quasi-geostrophic model, the influence of cold pools has lacked a theoretical framework until now. Fu’s research introduces a novel cloud chain model to better understand how cold pools influence the size of TC embryos.
The cloud chain model proposed by Fu and his team examines the interplay between rain evaporation, wind speed, humidity, and sub-cloud moisture convergence. Essentially, the model shows that the amount of rain evaporation during a single convective event determines the wind speed and humidity at the edge of the cold pool. This, in turn, affects the amount of moisture convergence beneath the cloud, influencing the intensity of the next-generation cold pool. The model also reveals that cold pools have a nonlocal dependence on air-column humidity, meaning their influence extends beyond their immediate vicinity. The range of this influence is determined by the size of the cold pool and a convective memory weight, which is influenced by mechanical lifting and thermodynamic forcing.
One of the key parameters in this model is the ratio of rain evaporation to surface evaporation within a cold pool. By coupling the cloud chain model with the quasi-geostrophic equation, Fu’s team derived an analytical expression for the size of TC embryos. While the theory captures the general trend observed in cloud-permitting simulations, it tends to overestimate the size of TC embryos. This discrepancy may be due to the oversimplification in estimating the fractional contribution of cold pools to convective initiation.
For the energy sector, understanding the factors that influence tropical cyclone formation and intensity is vital for preparedness and mitigation strategies. By improving the accuracy of tropical cyclone predictions, energy companies can better protect their infrastructure, ensure the safety of their personnel, and maintain the reliability of energy supply. The research conducted by Fu and his team contributes to this understanding by providing a theoretical model that explains the role of cold pools in TC embryo size, ultimately aiding in more accurate predictions and better preparedness for these powerful storms. The research was published in the journal Geophysical Research Letters.
This article is based on research available at arXiv.