Rochelle Wigley

A new digital bathymetric model of the world's oceans

General Bathymetric Chart of the Oceans (GEBCO) has released the GEBCO_2014 grid, a new digital bathymetric model of the world ocean floor merged with land topography from publicly available digital elevation models. GEBCO_2014 has a grid spacing of 30 arc seconds, and updates the 2010 release (GEBCO_08) by incorporating new versions of regional bathymetric compilations from the International Bathymetric Chart of the Arctic Ocean (IBCAO), the International Bathymetric Chart of the Southern Ocean (IBCSO), the Baltic Sea Bathymetry Database (BSBD), and data from the European Marine Observation and Data network (EMODnet) bathymetry portal, among other data sources. Approximately 33% of ocean grid cells (not area) have been updated in GEBCO_2014 from the previous version, including both new interpolated depth values and added soundings. These updates include large amounts of multibeam data collected using modern equipment and navigation techniques, improving portrayed details of the world ocean floor. Of all non-land grid cells in GEBCO_2014, approximately 18% are based on bathymetric control data, i.e., primarily multibeam and single beam soundings, or pre-prepared grids which may contain some interpolated values. The GEBCO_2014 grid has a mean and median depth of 3897 m and 3441 m, respectively. Hypsometric analysis reveals that 50% of the Earths surface is comprised of seafloor located 3200 m below mean sea level, and that ~900 ship-years of surveying would be needed to obtain complete multibeam coverage of the worlds oceans.

An unmanned seafloor mapping system: The concept of an AUV integrated with the newly designed USV SEA-KIT

The concept for an autonomous seafloor mapping system for ocean exploration is being built to compete in the Shell Ocean Discovery XPRIZE competition (http://oceandiscovery. xprize.org) by the international team of Nippon Foundation / GEBCO Alumni (see: http://www.gebco-nf.com/). The Team is advised and mentored by selected GEBCO and industry experts, specialized in ocean mapping, geology, software development and naval architecture. The Team is distinguished by its extraordinary diversity with a global distribution of representatives from academic institutions, offshore survey and technology industries, as well as national hydrographic offices. A newly designed, innovative Unmanned Surface Vessel (USV), called SEA-KIT, will be built to cooperate with any Autonomous Underwater Vehicle (AUV) acting as the remote surface access to the deep ocean. The major role of the SEA-KIT in the competition design is 1) the transportation of a commercially available AUV to and from the land launch site to the survey area and 2) the deployment and recovery of the AUV. Additionally, the SEA-KIT surface vessel will offer a positioning solution during AUV operations. Furthermore, if the USV is equipped with hydroacoustic devices, it can function as a stand-alone survey platform for any water depths dependent on the characteristics of the mounted echosounder. Positioning of the SEA-KIT will be realized using the High-Precision Global Navigation Satellite System (GNSS) positioning data. Satellite and radio communication solutions will be used for data transmission between the remote offshore system and the home base (onshore or mothership) components. Communication between SEA-KIT and the AUV will be performed by means of acoustic signals from an Ultra Short Base Line (USBL) device. Those signals are used for positioning and underwater data transmission. This data will be used for continuous AUV position calculation, using information about the AUV position relative to SEA-KIT. SEA-KIT will also be equipped with an Acoustic Doppler Velocity Log (DVL), Pressure Depth Sensor and an Inertial Measurement Unit (IMU). Automated functions for data processing will be considered.

Nippon foundation / GEBCO ocean mapping training program at the university of New Hampshire: 13 years of success and alumni activities

The General Bathymetric Chart of the Oceans (GEBCO, http://www.gebco.net/) training of a new generation of hydrographers and scientists in ocean mapping has been funded by the Nippon Foundation, based in Tokyo, Japan, since 2004. The Nippon Foundation is a private, non-profit foundation, whose overall objectives include social innovation, assistance for humanitarian activities and global ocean management (http:// www.nippon-foundation.or.jp/en). The 14th class of Nippon Foundation / GEBCO Postgraduate Certificate in Ocean Bathymetry (PCOB) Training Program (http://www.gebco.net/training) will begin one year-long education for a Graduate Certificate at the Center for Coastal and Ocean Mapping / Joint Hydrographic Center in the University of New Hampshire in August 2017 (http://ccom.unh.edu/gebco). These six new individuals from Year 14 will join an international and active group of 78 Nippon Foundation / GEBCO Training Program alumni from 35 coastal states educated in ocean mapping over the last 13 years. These alumni working at national naval and hydrographic offices, industry, research institutes and universities represent a group of ocean mappers who take home a strong passion for the oceans, backed by a world-class education they will use to build capacity through sharing their knowledge and experiences in their home nations. Currently ∼80% of the alumni are still employed within the same organization they were attached to when selected for the Training Program and ∼97% are still working in ocean sciences. This strong retention of alumni is one of the greatest successes of the Nippon Foundation / GEBCO Training Program. This capacity-building Training Program consists of a combination of theoretical education and practical training. Obligatory and elective courses give the students a complex knowledge of topics related to hydrographic surveying and coastal and ocean mapping. The Summer Hydrographic Field Course is a culmination of the training; consisting of planning, practical realization and data analysis of hydrographic survey data of a specific area of New Hampshire coastal waters. The academic training is followed by a visit in an international laboratory, chosen individually for each student and a deep-water ocean mapping research cruise. This gives the students the opportunity to get familiarized with oceans-related research and to work in institutions abroad on their own relevant projects with the support of laboratory staff. The lab visit and research cruise round out the students training, help them build networks and deepen some of their newly-acquired theoretical knowledge. GEBCO (http://www.gebco.net) aims to provide the most authoritative, publicly-available bathymetry data sets for the worlds oceans and is a joint project of the International Hydrographic Organisation (IHO) and the Intergovernmental Oceanographic Commission (IOC) of UNESCO the United Nations Educational Scientific and Cultural Organization. Nippon Foundation / GEBCO Training Program alumni are now a significant group within the GEBCO organization, and are engaged in various regional and global mapping projects, including the Indian Ocean Bathymetric Compilation (IOBC), the International Bathymetric Chart of the Arctic Ocean (IBCAO), the International Bathy-metric Chart of the Southern Ocean (IBSCO) and the GEBCO Sub-Committee on Undersea Feature Names (SCUFN). The diverse backgrounds, academic skills and practical experiences and knowledge of the Nippon Foundation / GEBCO alumni group, has being capitalized on in a number of alumniled initiatives. The alumni supported by industry and GEBCO experts, are, for example, currently developing an alternative integrated and remote mapping system solution for the Shell Ocean Discovery XPRIZE competition participation.