Recent observations of meteotsunamis on the Finnish coast
Pellikka, H.; Rauhala, J.; Kahma, K.K.; Stipa, T.; Boman, H.; Kangas, A. (2015). Recent observations of meteotsunamis on the Finnish coast, in: Vilibic, I. et al. Meteorological tsunamis: The U.S. East Coast and other coastal regions. pp. 197-215. http://dx.doi.org/10.1007/978-3-319-12712-5_11 In: Vilibic, I.; Montserrat, S.; Rabinovich, A.B. (Ed.) (2015). Meteorological tsunamis: The U.S. East Coast and other coastal regions. Previously published in Natural Hazards, Volume 74, Issue 1, 2014. Springer: Cham. ISBN 978-3-319-12711-8. 303 pp. https://dx.doi.org/10.1007/978-3-319-12712-5, more |
Keyword | | Author keywords | Meteotsunami Sea-level variations Tide-gauge records Baltic Sea Gulf of Finland Gulf of Bothnia |
Authors | | Top | - Pellikka, H.
- Rauhala, J.
- Kahma, K.K., more
| - Stipa, T.
- Boman, H.
- Kangas, A.
| |
Abstract | We present four case studies of exceptional wave events of meteorological origin, observed on the Finnish coast in the summers of 2010 and 2011. Eyewitnesses report unusually rapid and strong sea-level variations (up to 1 m in 5–15 min) and strong oscillating currents during these events. High-resolution sea-level measurements confirm the eyewitness observations, but the oscillations recorded by tide gauges mostly have a considerably smaller amplitude. The oscillations coincide with sudden jumps in surface air pressure at coastal observation stations, related to the passage of squall lines or gust fronts. These fronts propagate above the sea at a resonant speed, allowing efficient energy transfer between the atmospheric disturbance and the sea wave that it generates. Thus, we interpret the observed sea-level oscillations as small meteotsunamis, long tsunami-like waves generated by meteorological processes and resonance effects. |
|