Sea level surges of June 2011 in the NE Atlantic Ocean: observations and possible interpretation

Lessons Derived from Two High-Frequency Sea Level Events in the Atlantic: Implications for Coastal Risk Analysis and Tsunami Detection

“…It can be seen that the event recorded in Langosteira reflects not only a small increase of the magnitude of the signal, with waves reaching amplitudes of 10-15 cm, but also the appearance of higher frequency oscillations, with energy suddenly present at all the lower periods up to 2 or 2.5 min, as observed in the events of 2014 presented in previous section, along with the 15-25 min period signal already present before the event. Once again, it seems there is a kind of permanent background oscillation in this band of frequencies in this part of the Spanish coast, observed now also at Langosteira and Gijón tide gauges, similar to the one observed at Coruña during January-February 2014, and to the one found by Frère et al (2014).…”

“…It seems the signal is present before and after the increase of the oscillations amplitude and is also clear in the background noise spectra of 1 min data in Figure 9. This signal is not present or is very small in La Palma tide gauge (Canary Islands), but it is close to one found for the event of June 2011, on almost all the stations (Frère et al, 2014); this would discard a local topographic feature being responsible for this frequency peak although Frère et al did not find a clear explanation about their origin. A spectrogram of the 1-min atmospheric pressure from Vigo tide gauge (not shown) revealed that this was the only band of frequencies with significant variance in the high temporal resolution atmospheric pressure data for all these weeks.…”

“…Detection of fast atmospheric pressure jumps is usually difficult from existing meteorological networks as the sampling of most of the stations is too infrequent (10 min to 1 h). This is the case for the buoys of PdE network but also for others as described in Frère et al (2014). The sampling interval of these buoys is 1 h, far from the 1 min temporal resolution required for implementation of future meteotsunami warning systems.…”

“…It is necessary to determine, first, the origin of these oscillations: in the absence of an earthquake and the coincidence with such big waves the first impression is that they are infragravity waves, very common in the Spanish Atlantic harbors, as already mentioned; nevertheless, they might also be meteotsunamis like those described in Frère et al (2014). That paper described a meteotsunami event which occurred on June 26-28, 2011 in this region and which was recorded by all the tide gauges presented here, as well as at other stations from Portugal to England.…”

Examination of Generation Mechanisms for an English Channel Meteotsunami: Combining Observations and Modeling

“…Numerical models have provided evidence supporting Greenspan resonance in the Great Lakes (Ewing et al 1954;Anderson et al 2015) and Proudman resonance in Adriatic ( Sepić et al 2015), Balearic (Li cer et al 2017, and East China Sea (Hibiya and Kajiura 1982). Frère et al (2014) and Tappin et al (2013) have suggested that Proudman resonance was responsible for observed meteotsunamis around the United Kingdom, but this has never been demonstrated through numerical modeling, as we do here.…”