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The colonization of underwater environments by exotic seaweeds is causing major ecological problems around the world. This project, referred to AMALIA, aims to transform this current ocean threat into an opportunity by adding value to the macroalgae present off the northwest of the Iberian Peninsula. To do so and to observe the presence of seaweeds in situ, an ocean modular submersible platform was developed. This platform was designed to be capable of detecting and surveying surges of invasive seaweeds while withstanding sea conditions. Conceptual designs followed by a screening process were performed, taking into consideration criteria such as operational range and modularity. An open-frame lander was considered and further developed using buckling criteria. In parallel, a state-of-the-art monitoring system was created using spectral imaging, allowing for the future creation of a macroalgae identification system. In addition, sensorial systems for characterizing growth conditions were introduced. Laboratory trials were executed to assess the capability of the system, and sea trials are currently being performed. Numerical simulations and laboratory trials indicate that the structure is fully capable of being deployed for shallow-water environments with a state-of-the-art invasive seaweed monitoring system while maintaining a high degree of modularity. [ABSTRACT FROM AUTHOR]

The oceans cover 71% of the earth's surface. Yet our knowledge about the vast expanse of our oceans is very limited. Oceans play a major important role in influencing weather and climate. This requires us to have measurements of various ocean parameters both in-situ and remotely. Remote measurement by satellites is not adequate for ocean parameter characterization. An oceanographer needs in-situ measurements with high resolution and accuracy. There are a number of factors which make our marine environments hostile: their sheer size, increasing pressure with depth, temperature variations, lack of visibility, and limitations on the travel of electromagnetic waves underwater, all pose a great hindrance to their exploration which in turn affects our understanding. This article discusses the challenges faced by any marine instrument in the marine environment and what can be done to tackle them. [ABSTRACT FROM AUTHOR]

Marine environments are currently subject to strong ecological pressure due to local and global anthropic stressors, such as pollutants and atmospheric inputs, which also cause ocean acidification and warming. These strains can result in biogeochemical cycle variations, environmental pollution, and changes in benthic-pelagic coupling processes. Two new devices, the Amerigo Lander and the Automatic Benthic Chamber (CBA), have been developed to measure the fluxes of dissolved chemical species between sediment and the water column, to assess the biogeochemical cycle and benthic-pelagic coupling alterations due to human activities. The Amerigo Lander can operate in shallow as well as deep water (up to 6000 m), whereas the CBA has been developed for the continental shelf (up to 200 m). The lander can also be used to deploy a range of instruments on the seafloor, to study the benthic ecosystems. The two devices have successfully been tested in a variety of research tasks and environmental impact assessments in shallow and deep waters. Their measured flux data show good agreement and are also consistent with previous data.

This technical note provides a summary of a uniquely designed tsunami early warning system consisting of an ocean bottom seismometer, an accelerometer, a differential pressure gauge, and a bottom pressure recorder. The system has ad-vantages over other tsunameters currently in use because it receives power and reports data continuously, via fiber-optic cable, allowing for the maximum amount of lead time between receipt and analysis of data; warnings may then be issued earlier, resulting in additional time to evacuate vulnerable areas. The system was developed in a collaborative effort between Woods Hole Oceanographic Institution and Lighthouse R&D Enterprises, Inc., during 2006 and installed in 2007 off the northern coast of Oman on an extended portion of a preexisting physical ocean-ographic cabled monitoring system. The goal was to produce a system capable of determining the magnitude and mechanism of earthquakes--even very large, local ones--and of sensing the large-wavelength, low-amplitude waves character-istic of tsunamis in the open ocean. Since 2009, the system has been recognized by the International Tsunameter Partnership (commissioned by the Intergovernmental Oceanographic Commission of the United Nations Educational, Scientific and Cul-tural Organization) as operational, but it has yet to be integrated with national or regional warning centers. A numerical modeling suite was developed to estimate tsunami impact at any given location along the Omani coast and is intended to func-tion as a complementary tool for analysis of the real-time data. Real-time data re-ceipt combined with accurate analysis will lead to earlier and more reliable warnings that may help save additional lives. [ABSTRACT FROM AUTHOR]

Marine environments are currently subject to strong ecological pressure due to local and global anthropic stressors, such as pollutants and atmospheric inputs, which also cause ocean acidification and warming. These strains can result in biogeochemical cycle variations, environmental pollution, and changes in benthic-pelagic coupling processes. Two new devices, the Amerigo Lander and the Automatic Benthic Chamber (CBA), have been developed to measure the fluxes of dissolved chemical species between sediment and the water column, to assess the biogeochemical cycle and benthic-pelagic coupling alterations due to human activities. The Amerigo Lander can operate in shallow as well as deep water (up to 6000 m), whereas the CBA has been developed for the continental shelf (up to 200 m). The lander can also be used to deploy a range of instruments on the seafloor, to study the benthic ecosystems. The two devices have successfully been tested in a variety of research tasks and environmental impact assessments in shallow and deep waters. Their measured flux data show good agreement and are also consistent with previous data. [ABSTRACT FROM AUTHOR]