Les vagues scélérates

The present article introduces and defines what are the rogue or freak waves. After an historical reminder on the recent consideration of their existence, several events of waves having struck big or small ships or still the coastline are presented. A paragraph is dedicated to the scientific explanation of the phenomenon and the difference with other phenomenons such tsunamis or tidal bores is clarified. After a reminder of the international mobilization towards a forecast system, a conclusion focuses on events met in New Caledonian waters and analyzes more exactly testimonies related to this type of phenomenon by trying to clarify their causes.

Géodiversité sous-marine de Nouvelle-Calédonie. 1ère partie

The object of this article is to offer a synthesis of the knowledge clarifying the originality and the diversity of the submarine geological formations of the New Caledonian EEZ. A reminder is given onto the geologic history of the region, based upon the dislocation of the Gondwana Continent, the opening of the Tasman Sea, the presence of submarine volcanism, the setting up of heavy peridotitic rocks, the building up of the Fairway and Lord Howe Ridges and of sedimentary basins, the formation of volcanic domes and sea-mounts or guyots, the subduction along the Vanuatu Trench, the uplift of the Loyalty Islands, the development of carbonated ptatforms around the islands etc.... Of this complex history ensues an exceptional submarine geo-diversity. After this presentation the article clarifies the methods and the tools used in marine geosciences to map, explore, observe, analyze, sample, that they are embarked or are autonomous, teleoperated or inhabited systems. A chapter describes the programs which were set up since about forty years and the results obtained as well as the scientific teams concerned with. In conclusion, based on the unpublished character of this geo-diversity, the article introduces the second text to come in a next issue of theTai Kona magazine, text which will focus on the scientific, economic (mineral resources), environmental (deep biodiversity) and risks (seismicity) challenges that are worn by one of the most original submarine geologic context in the world.

Etats Généraux de la Mer en Nouvelle-Calédonie. Auditorium de la Province Sud 5 et 6 juillet 2016. Déroulé, Participation, Enseignements

Ce texte de 76 pages, dont annexes, est le compte rendu du déroulé et des enseignements tirés des premiers Etats Généraux de la Mer qui se sont tenus les 5 et 6 juillet 2016 en Nouvelle-Calédonie (Auditorium de la Province Sud à Nouméa). Après un Préambule ce compte rendu explicite le déroulé, la participation, le cas des 6 tables rondes et de leur restitution, les discussions et enseignements. Ce texte fait également un point sur les éléments à améliorer et adresse des remerciements. 5 annexes complètent ce compte rendu. - Annexe 1 : Déroulé des Etats Généraux de la Mer - Annexe 2 : Diaporama de présentation du rapport de synthèse sur les enjeux maritimes de la Nouvelle-Calédonie. - Annexe 3 : Diaporama de présentation des activités et questions posées en Polynésie française - Annexe 4 : Diaporama de présentation des activités et questions posées au niveau national - Annexe 5 : Diaporamas de restitution des tables rondes 1, 2, 3, 4, 5 et 6

Un drone marin écoresponsable vogue en Nouvelle-Calédonie

This text presents and explicits the story of a marine drone: the Wave Glider, designed and developed by Liquid Robotics, an American company of the Silicon Valley. The text specifies its functioning, directly dependent on energies that are the swell and the sun and its technical characteristics authorizing a set of measures of in situ parameters (sea temperature, salinity, currents, marine acoustics, video but also meteorological data acquisitions). A set of scientific or operational applications is also introduced. A detail is supplied on the first experience led in New Caledonia: inaugural mission of the drone Wave Glider, property of the Company Assystem, for a route between Nouméa and Lifou and return. Several perspectives of use of such a tool in New Caledonia and in the Pacific are proposed.

Les macro-déchets en mer

This text presents the general problem of nuisance and pollution created by macro-waste at sea. We clarify three main types of pollution: that of coasts, that of the sea bed and that of the open sea. The article leans on scientific data: report of the state of contamination of the coasts of France by macro waste (1982), results of works and oceanographic sea bed observation campaigns, evaluation of the contamination by micro-plastics floating on surface and concentrating in the big oceanic gyres. A paragraph is dedicated to the impacts on the ecosystems, an other one on the taken measures to fight against those macro-waste. The specific case of New Caledonia is not forgotten and in conclusion we underline the necessity of an education of the populations in terms of Eco responsibility, which appears to be a significant factor of regression of this type of nuisance that affects all the seas of the world