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This paper describes the application of a third-generation wave model and a hydrodynamic model to determine extreme waves and water levels associated to the incidence of tropical cyclones along the Mexican coast. In addition to historical records and to overcome the limitation associated to data scarcity in Mexico, we employ information from 3100 synthetic events generated from a statistical/deterministic hurricane model. This enables the generation of a more robust database for the characterization of extreme water levels along the Mexican coast. The procedure incorporates a storm track modeling approach where, for each hurricane (historic and synthetic), the entire track is numerically reproduced as it crosses the ocean and makes landfall. Extreme values for both, waves and storm surge, are determined through an extreme value analysis at each mesh element, allowing for the identification of their spatial variability. Results for the Gulf of Mexico show that highest waves are expected along both the Caribbean Sea and the northern coast of the Gulf of Mexico, while extreme water levels due to storm surge are identified in the northern part of the Yucatan Peninsula. On the other hand, along the Pacific coast, extreme values for waves are identified at the central mainland Mexico while storm surge is minimal. The methodology is proved to be a good alternative in the reproduction of continuously varying tropical cyclone climatology along the Mexican coastline, and it provides a rational approach for assessing the hurricane-induced risk in coastal areas. [ABSTRACT FROM AUTHOR]

SUMMARY We conduct a detailed seismological study of the large Colima, Mexico earthquake of 1932 June 3 and of its aftershocks of June 18 and 22. The latter (Event III) generated a tsunami more devastating than that of the main shock despite much smaller seismic magnitudes, thus qualifying as a so-called 'tsunami earthquake'. Relocation based on published arrival times shows that Event III took place up-dip of the main shock. The analysis of the spectral amplitude of mantle surface waves yields low-frequency moments of 24, 5.2 and 4 times 1027 dyn cm, respectively, with Event III featuring a moment growing with period, which expresses the source slowness characteristic of 'tsunami earthquakes'. This is confirmed by a deficient energy-to-moment ratio, as derived from high-frequency P waves recorded at Pasadena. Near-field hydrodynamic simulations show that the effects of the main shock's tsunami are well modelled by a standard seismic source, whereas the stronger tsunami from Event III can be modelled by rupture along a splay fault in a mechanically deficient material. All our results then fit the model for 'tsunami earthquake' aftershocks proposed for the Kuril Islands by Fukao in 1979. [ABSTRACT FROM AUTHOR]

For a period of 22 months beginning in September 2003, an array of four current profilers were deployed on the Puerto Morelos fringing reef lagoon, a microtidal Caribbean environment characterised by the influence of the Yucatan Current (YC) and a Trade Wind regime. The dataset includes water currents, bottom pressure, and surface waves complemented with coastal meteorological data and surface currents from an acoustic Doppler current profiler moored 12 km offshore. Normal circulation conditions consisted of a surface wave-induced flow entering the lagoon over a shallow reef flat and strong flows exiting through northern and southern channels. This wave induced flow was modulated by a low-frequency sea level change related to a geostrophic response to the YC variability offshore, with tidal and direct wind forcing playing additional minor roles. Under extended summer low-wave height conditions, together with a decrease in sea level from the intensification of the offshore current, the exchange of the lagoon with the adjacent ocean was drastically reduced. Under normal wave conditions (HS = 0.8 ± 0.4 m, mean ± SD), water residence time was on average 3 h, whereas during Hurricane Ivan's extreme swell (HS = 6 m) it decreased to 0.35 h. [ABSTRACT FROM AUTHOR]

Climate change has unchained several natural extreme phenomena, including a major frequency and intensity of flooding episodes. From these, the ones of greatest importance are those which endanger human settlements as well as socioeconomic activities. This is the case of Tamuín city, settled in the shore of Tampaón River, in Mexico. In this work, we performed a detailed numerical modelling of the hydrodynamics of the zone, considering in situ topographic and bathymetric data as well as hydrodynamic parameters. Severe rainfall scenarios were simulated in order to determine the zones which are prone to flooding, as well as the potential periods of time between the beginning of the rainfall up to the flooding, considering the potential effects of climate change in the precipitation rate. The outcome of this research will help local governments undertake preventive actions to reinforce the identified risky zones, thus providing an adequate protection of rural and urban zones, as well as their inhabitants and their economical activities from current and future floods, considering potential climate change effects. [ABSTRACT FROM AUTHOR]

This article reflects on the 12th International Biennial Conference on Physics of Estuaries and Coastal Seas (PECS) held in Mérida, México from October 19 to 22, 2004. PECS philosophy has been to stimulate the cooperation between the coastal engineers and coastal oceanographers. The topic of PECS 2004 was Hydrodynamics and Morphodynamics in Estuaries and Coastal Seas, including estuarine hydrodynamics, coastal hydrodynamics, coastal transport and morphodynamics.