Introduction to “Tsunamis in the World Ocean: Past,Present, and Future. Volume II”

Fifteen papers are included in Volume 2 of a PAGEOPH topical issue Tsunamis in the World Ocean: Past, Present, and Future. These papers are briefly introduced. They are grouped into three categories: reports and studies of recent tsunamis, studies on tsunami statistics and application to tsunami warning, and modeling studies of tsunami runup and inundation. Most of the papers were presented at the 24th International Tsunami Symposium held 14–16 July 2009 in Novosibirsk, Russia, and reflect the current state of tsunami science.     

Introduction to “Historical and Recent Catastrophic Tsunamis in the World: Volume II. Tsunamis from 1755 to 2010”

Eighteen papers on past and recent destructive tsunamis are included in Volume II of the PAGEOPH topical issue “Historical and Recent Catastrophic Tsunamis in the World.” Three papers discuss deep-sea (DART) and coastal tsunami observations, warning systems and risk management in the Pacific Ocean. Four papers examine the 1755 Lisbon, 1964 Alaska, 2003 Algeria, and 2011 Haiti tsunamis. Four more papers, as well as some papers in Volume I, report on various aspects of the 2010 Chile tsunami. Two papers present some results of field survey and modelling investigation of the 2010 Mentawai, Indonesia, tsunami. Three papers report on modelling efforts of tsunami generation by earthquake and landslide, and of tsunami propagation. Finally, two papers discuss hazard assessment using a probabilistic approach.     

Introduction to “Historical and Recent Catastrophic Tsunamis in the World: Volume I. The 2011 Tohoku Tsunami”

Twenty-one papers on the 2011 Tohoku, Japan tsunami are included in Volume I of the PAGEOPH topical issue “Historical and Recent Catastrophic Tsunamis in the World.” Two papers discuss seismological aspects of the event with an emphasis on tsunami generation and warning. Five papers report the impacts and effects in Japan through field surveys of tsunami heights, building damage, and tsunami deposits or analysis of satellite data. Eight papers report the tsunami effects on other Pacific coasts, including the Kuril Islands, the USA, French Polynesia, the Galapagos Islands, Australia, and New Zealand. Three papers report on analyses of the instrumental records of the 2011 Tohoku tsunami, and two more papers report their modelling efforts of the tsunami. Several of the above papers also compare the 2011 Tohoku and 2010 Chile tsunamis.     

Introduction to “Tsunami Science Four Years After the 2004 Indian Ocean Tsunami, Part I: Modelling and Hazard Assessment”

In this introduction we briefly summarize the 14 contributions to Part I of this special issue on Tsunami Science Four Years after the 2004 Indian Ocean Tsunami. These papers are representative of the new tsunami science being conducted since the occurrence of that tragic event. Most of these were presented at the session: Tsunami Generation and Hazard, of the International Union of Geodesy and Geophysics XXIV General Assembly held at Perugia, Italy, in July of 2007. That session included over one hundred presentations on a wide range of topics in tsunami research. The papers grouped into Part I, and introduced here, cover topics directly related to tsunami mitigation such as numerical modelling, hazard assessment and databases. Part II of this special issue, Observations and Data Analysis, will be published in a subsequent volume of Pure and Applied Geophysics.     

Introduction to “Tsunami Science Four Years After the 2004 Indian Ocean Tsunami, Part II: Observation and Data Analysis”

In this introduction we briefly summarize the fourteen contributions to Part II of this special issue on Tsunami Science Four Years After the 2004 Indian Ocean Tsunami. These papers are representative of the new tsunami science being conducted since the occurrence of that tragic event. Most of these were presented at the session: Tsunami Generation and Hazard, of the International Union of Geodesy and Geophysics XXIV General Assembly held at Perugia, Italy, in July of 2007. That session included over one hundred presentations on a wide range of topics in tsunami research. The papers grouped into Part II, and introduced here, cover field observations of recent tsunami’s, modern studies of historical events, coastal sea-level observations and case studies in tsunami data analysis.     

Deep Electromagnetic Studies from Land, Sea, and Space: Progress Status in the Past 10?Years

This review paper summarizes advances in deep electromagnetic studies of the Earth in the past decade. The paper reports progress in data interpretation, with special emphasis on three-dimensional and quasi one-dimensional developments, and results. The results obtained from data of different origin—geomagnetic observatories, long-period magnetotelluric experiments, submarines cables, and from low-Earth orbiting geomagnetic satellite missions—are described. Both frequency-domain and time-domain approaches are addressed. Perspectives for the future are also discussed.     

Phytoplankton dynamics in the central Great Barrier Reef—I. Seasonal changes in biomass and community structure and their relation to intrusive activity

Phytoplankton dynamics in the central Great Barrier Reef and the relation of these dynamics to the seasonal upwelling of nutrient-enriched Coral Sea water onto the outer continental shelf were followed over an annual cycle. Event scale changes were sampled by frequent (2-day to 2-week) re-occupations of a cross-shelf transect during the latter half of the summer. Intrusive activity between November and April episodically injects nitrate-N enriched water into oligotrophic shelf waters. Persistent mid-shelf and intermittent outer shelf mid-water phytoplankton accumulations were observed from late-January to March. The 10, 10to2and<2μm phytoplankton size fractions were, respectively, dominated by diatoms, microflagellates + unarmored dinoflagellates and unicellular cyanobacteria + coccoid eukaryotes + very small flagellates. In the absence of intrusive activity, nanoplankton (10 to 2 μm) and picoplankton (<2μm) dominated biomass. These two size fractions dominated biomass on the outer shelf and in the Coral Sea throughout the year. Picoplankton frequently made up50% of the chlorophyll standing crop. Mid-shelf blooms, in which the highest chlorophyll levels (2μg 1⁻¹) were found, were largely due to increases of the 10μm fraction. In contrast to marked summer fluctuations of mid-shelf diatom populations, nano- and picoplankton standing crop varied little with time, cross-shelf location or depth. Low water column DIN levels and DIN:Chla ratios suggest phytoplankton populations were nitrogen-limited. In open waters of the central GBR, phytoplankton apparently convert most of the intruded nitrogen into particulate form.     

Comment on Sousa, M. L. and Costa, A. C., ��Ground motion scenarios consistent with probabilistic seismic hazard disaggregation analysis. Application to Mainland Portugal��

Disaggregation of the seismic hazard has become a popular technique to convey information on the main sources contributing to the hazard at a particular site. Recently published work adopts geographic disaggregation analysis of seismic hazard as a tool to identify dominant rupture scenarios for municipalities in Mainland Portugal. The authors conclude that the seismic hazard in South and Central Portugal is dominated by the seismicity that takes place offshore, around 70km WSW of Cape S. Vicente, both for the return periods of 475 years and 975 years. Whilst recognizing the merits of the approach taken and the utility of the tools developed, we take issue with this last conclusion. We consider that the proposed disaggregation returns a picture of the biases in the hazard analysis, more than any real feature of the distribution of relevant seismogenic sources.     

Marine resources,biophysical processes,and environmental management of a tropical shelf seaway: Torres Strait,Australia–Introduction to the special issue

This special issue of Continental Shelf Research contains 20 papers giving research results produced as part of Australia's Torres Strait Co-operative Research Centre (CRC) Program, which was funded over a three-year period during 2003–2006. Marine biophysical, fisheries, socioeconomic-cultural and extension research in the Torres Strait region of northeastern Australia was carried out to meet three aims: 1) support the sustainable development of marine resources and minimize impacts of resource use in Torres Strait; 2) enhance the conservation of the marine environment and the social, cultural and economic well being of all stakeholders, particularly the Torres Strait peoples; and 3) contribute to effective policy formulation and management decision making. Subjects covered, including commercial and traditional fisheries management, impacts of anthropogenic sediment inputs on seagrass meadows and communication of science results to local communities, have broad applications to other similar environments.