RT doctoral thesis
T1 Analysis of the spatio-temporal sea level variability in extreme regions using in-situ and satellite remote sensing data: South Shetland region (Antarctica)
A1 Luengo Sánchez, Olga
A2 Física Aplicada
A2 Matemáticas
AB This thesis analysessea level variability in the South Shetland Islands through the integrationof satellite altimetry, long-term in-situ oceanographic observations, and the analysis ofextreme geophysical events. The study provides new insights into the processes that drivepolar coastal environments.The validation of Sentinel-3A and Sentinel-3B altimetric sea level anomaly products againsttide gauge data showed that the agreement between satellite and in-situ measurements washighly sensitive to processing parameters and environmental conditions. Optimised settings,particularly the use of nine surrounding measurements to the crossover and a sea state biascorrection of 5% of the significant wave height, yielded the lowest discrepancies with tidegauge records. Sea ice was identified as the main limitation for altimetry in the region,introducing data gaps and contaminating altimeter returns. These results highlight theimportance of methodological refinement, including adaptive masking and improvedretracking, to increase the robustness of polar altimetry.Temperature series from LIVMAR (Livingston Island) and DECMAR (Deception Island)stations revealed clear seasonal cycles modulated by local processes. Volcanic and tectonicactivity, such as the 2020 Orca seamount activity, were associated with thermal anomalies,while glacier meltwater discharge was linked to earlier and more variable minima atLivingston. Three phases of thermal evolution were identified over the last decade, reflectingthe combined effects of regional atmospheric variability and local geophysical forcing.In addition, the January 2022 Hunga Tonga–Hunga Ha’apai eruption generated atmosphericLamb waves that were detected at Antarctic meteorological stations and triggeredmeteotsunamis at Livingston and Deception Islands. The responses at both sites highlighthow atmospheric forcing generated long ocean waves that, once established, were shaped bylocal basin geometry in terms of amplitude and frequency.Overall, the results demonstrate that sea level variability in the South Shetland Islands isdriven by the combined influence of large scale climatic factors, local volcanic and glacialprocesses, and extreme remote events. By integrating multiple approaches, this thesiscontributes to reducing uncertainties in global sea level monitoring and to a morecomprehensive understanding of sea level variability in this region of Antarctica.
YR 2026
FD 2026
LK http://hdl.handle.net/10498/39688
UL http://hdl.handle.net/10498/39688
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 06-nov-2026