###### Abstract  
Gas consumption is subject to large seasonal fluctuations between the summer season (period with lower request) and the winter season (time with increased consumer demand). Underground gas storage applications (UGS) help to ensure a steady and reliable supply of natural gas, even during periods of peak demand, smoothing price fluctuations and providing a means of balancing the supply and demand of natural gas on a daily, weekly, or seasonal basis. However, UGS activities can induce vertical ground displacement, which is usually strictly associated with the injection and withdrawal of gas into/from the reservoir. It is necessary to carefully monitor and manage the potential impact of UGS activities on the subsurface and surface to ensure the stability and safety of the local environment. The Interferometric Synthetic Aperture Radar (InSAR) technique can provide a wide range of high-precision information on seasonal surface deformation associated with UGS activities useful for increasing the amount of information on ground deformation monitoring. This study introduces a unique and replicable approach to investigating freely available ground movement data for a fractured aquifer reservoir located in the Madrid Basin (Guadalajara, Spain), which is currently employed for seasonal underground gas storage applications. Notably, this study gives a comprehensive comparison of InSAR results of UGS activity in a deep aquifer, leveraging data that are entirely open-source and easily accessible. The Yela UGS project exploits a carbonate reservoir (dolomite) managed, since 2012, by Enagas, the Spanish main Transmission System Operator (TSO). InSAR data from 2015 to 2021 provided a full and coherent ground deformation pattern of the area. Based on this data, a fully integrated volumetric variation model was developed, elucidating the effects of gas storage activity. A significant correlation between the periodic injection/withdrawal rates of natural gas and InSAR ground deformation over time was identified. underground gas storage; InSAR; monitoring; ground deformation; EGMS 202316639220331663920316639203166392031663920316639203166392031663920316639203166392031663920316639203166392031663920316639203163920316392031639203163920316392031639203163920316  
low demand for natural gas, and (ii) the winter season with low atmospheric temperature and corresponding high demand. Each reservoir type has its own physical features that govern its suitability for specific applications [1]. Natural porous strata typically possess a substantial storage capacity but exhibit lower injection and withdrawal rates. In contrast, salt caverns often have a more limited storage capacity but allow for higher injection and extraction rates [2; 3]. The worldwide interest in UGS applications is demonstrated by the increasing global underground gas storage capacity, which reached 475 \(\times\) 10\({}^{9}\) Sm\({}^{3}\) (Standard m\({}^{3}\)) in 2022, more than four times that available in 1970 [5]. In 2016, there were 143 active project sites in Europe, while by the end of 2021, the number was 160, 35% of which were in Germany (Table 1) [6]. The total European underground gas storage capacity is approximately 100 billion m\({}^{3}\)[7]. The number and sizes of facilities vary greatly. A total of 73% of the total European capacity