IBCAO Version 4.0 Advances High-Resolution Mapping of the Arctic Ocean Floor

A newly released depth model of the Arctic Ocean seafloor has been published in Nature journal Scientific Data, marking a major milestone in polar bathymetry. The updated dataset, known as Version 4.0 of the International Bathymetric Chart of the Arctic Ocean (IBCAO), is delivered as a digital gridded database that significantly enhances the resolution and coverage of Arctic Ocean mapping.

This latest compilation was completed under the leadership of the Regional Center for the Arctic and North Pacific Ocean, operating within The Nippon Foundation–GEBCO Seabed 2030 Project. The Regional Center functions as one of four global hubs dedicated to advancing comprehensive ocean floor mapping. It is jointly administered by Stockholm University and the University of New Hampshire. The development of IBCAO 4.0 involved collaboration among scientists and cartographers from 15 countries, including representation from every Arctic-bordering nation.

Compared with the previous release in 2012, IBCAO Version 4.0 substantially expands mapped coverage. While Version 3.0 documented 6.7 percent of the Arctic Ocean with modern data, the new edition increases that figure to 19.6 percent. This improvement reflects years of dedicated hydrographic surveys, including extensive icebreaker expeditions that have collected high-quality multibeam sonar measurements beneath Arctic sea ice.

According to Professor Martin Jakobsson of Stockholm University, who co-leads the Regional Center alongside Professor Larry Mayer, the new Arctic grid forms the 2020 Arctic contribution to the broader GEBCO Global Grid initiative. The overarching objective of GEBCO is to achieve complete mapping of the world’s ocean floor by 2030. He emphasizes that a dedicated Arctic grid in polar projection is essential because global bathymetric grids become significantly distorted at high latitudes near the geographic poles, limiting their analytical accuracy in polar research.

Beyond cartographic advancement, IBCAO 4.0 provides a refined framework for scientific modeling. The improved seafloor representation strengthens predictive simulations related to the Greenland Ice Sheet and projections of global sea level rise. Accurate bathymetry is fundamental to understanding ocean circulation patterns, sub-ice shelf processes, and climate-driven feedback mechanisms in the Arctic region.

IBCAO 4.0 represents the fourth digital grid of the Arctic Ocean since the initiative was first established in St. Petersburg in 1997. Over the years, IBCAO datasets have become foundational to Arctic marine research and operational applications. With hundreds of thousands of downloads globally, these grids underpin a wide range of bathymetric analyses, from navigation planning to geophysical modeling.

About The Nippon Foundation–GEBCO Seabed 2030 Project

The Nippon Foundation, founded in Japan in 1962, is a private, nonprofit organization dedicated to philanthropic and social innovation initiatives. Funded through motorboat racing revenues, the Foundation supports diverse programs ranging from global health and peacebuilding to ocean stewardship and sustainable development. A core objective includes ensuring that marine knowledge and resources are preserved and shared for future generations.

The General Bathymetric Chart of the Oceans (GEBCO) operates as a joint program of the International Hydrographic Organization (IHO) and the Intergovernmental Oceanographic Commission (IOC) of UNESCO. As the only intergovernmental body formally mandated to map the entire ocean floor, GEBCO traces its origins to 1903, when Prince Albert I of Monaco initiated the first global bathymetric chart series. Today, GEBCO delivers authoritative, publicly accessible bathymetric datasets covering the world’s oceans.

Launched at the United Nations Ocean Conference in 2017 by Chairman Yohei Sasakawa of The Nippon Foundation, the Seabed 2030 Project coordinates global bathymetric data acquisition and integration efforts. The initiative operates through four Regional Centers—covering the Southern Ocean; the Arctic and North Pacific; the Atlantic and Indian Oceans; and the South and West Pacific—which supply processed data to the Global Data Centre in Southampton. Together, these centers compile contributions into the freely available GEBCO Grid, supporting the ambitious goal of mapping the entire ocean floor within this decade.