Towards practical radar-based atmospheric refractivity characterization

Resumo

Accurate and reliable climate modeling is crucial for the protection of the environment, people, and properties. The increase in the number of adverse weather events, such as droughts, floods, or heat waves, over the past few years has fostered research into ways to improve the accuracy, robustness, and quality of weather models in order to enable informed decision-making. The most direct way to achieve these improvements is to increase the quality and quantity of data used by climate prediction models. The work developed during this doctoral thesis focuses on using radar systems to support this idea. Aligned with this goal, a reliable and validated atmospheric refractivity estimation technique has been developed, and it can be deployed on radars from the current meteorological infrastructure without the need for any additional hardware. Since refractivity and its vertical gradient are closely related to atmospheric pressure, air temperature, and relative humidity, they are extremely valuable for high-precision climate modeling. Moreover, the use of geostatistical interpolation methods to generate two-dimensional refractivity maps from the derived radar estimations has demonstrated itself to be a solid alternative for areas whose natural orography hinders the performance of the system and reduces the spatial resolution of the method. This study, in addition to a new calibration approach based on publicly available reanalysis weather data instead of ground-based weather stations, allows for the smooth integration of radar-based refractivity estimation technology into the existing meteorological infrastructure while minimizing operational costs. The techniques proposed in this thesis have shown the viability of using the current weather radar network in a more efficient manner, taking advantage of their capacity to generate high-quality atmospheric data that can be used to develop better and more reliable climate prediction models. These methods have been validated using real radar systems operated by Meteogalicia, IPMA, and the Met Office.