High-frequency sea-level analysis: Global distributions

High-Frequency Sea-Level Extremes: Global Correlations to Synoptic Atmospheric Patterns

“…With the recent creation of the Minute Sea-Level Analysis (MISELA) dataset (Zemunik et al, 2021b) compiling global NSLOTTs records and the release of the hourly ERA5 atmospheric reanalyses (Hersbach et al, 2020), studying the link between NSLOTTs and atmospheric processes worldwide became possible. Therefore, this studywhich complements the research of Zemunik et al (2022) where global distributions, spectral properties and coherence patterns of NSLOTTs were examinedaims to demonstrate that the connection between synoptic settings and NSLOTTs can be established in the world oceans. A global NSLOTT index was thus constructed, individually at each of the 307 world locations extracted from the MISELA dataset, with the optimal combination of synoptic variables describing the atmospheric setup above each area during moderate and pronounced NSLOTTs.…”

Advances in the observation and understanding of changes in sea level and tides

“…Also of importance to the estimation of extreme sea levels is consideration of the higher‐frequency variability that is often missed by the hourly and similar sampling of some tide gauge data. This subhourly variability includes seiches generated by tides, winds, or waves, which can be several decimeters in magnitude 183–186 . The role of wave setup as well as the usually modeled wind setup is also an important consideration within the overall description of a storm surge 47,187,188 .…”

“…This subhourly variability includes seiches generated by tides, winds, or waves, which can be several decimeters in magnitude. [183][184][185][186] The role of wave setup as well as the usually modeled wind setup is also an important consideration within the overall description of a storm surge. 47,187,188 However, such an estimation may be a difficult undertaking when applied to many sites.…”

Observation of a meteotsunami on the south coast of Ireland

“…Observations of this event were possible due to the high‐frequency sampling (every 5 or 6min) of the Irish Marine Institute tide gauge network – other observations sample at a temporal frequency of 15min, such as the UK's National Tides and Sea Level Facility. Ideally, 1min sampling is necessary for identifying and categorising meteotsunamis (Zemunik et al ., 2022). Likewise, high‐frequency meteorological observations are necessary to attribute the driver of this event – no remarkable features were evident in the hourly station data nor on synoptic charts.…”