HF radar proposed as a wide area sensor for US Navy operations in a changing Arctic

Rising temperatures and shrinking sea ice are opening Arctic waters to more shipping, and an Australian physicist argues that high-frequency (HF) radar could help navies and governments keep watch over the region as activity there grows.

Stuart Anderson, an Adjunct Professor in Adelaide University's School of Physics, Chemistry and Earth Sciences, has assessed how HF radar could support future US Navy operations in the Arctic. His analysis covers three roles for the technology: wide-area surveillance, ocean monitoring and communications support.

The Arctic is changing quickly. Warming is reducing sea ice cover and making routes such as the Northern Sea Route and the Northwest Passage more accessible to ships.

Greater access is expected to bring growth in commercial shipping, resource extraction and fishing across the region. Strategic competition among nations is intensifying at the same time, adding new security and operational challenges.

Anderson presented a paper on the subject at the 2026 IEEE Radar Conference in Phoenix, Arizona. It examined how HF radar, already used for ocean surveillance in Australia and other parts of the world, might be adapted to the unique Arctic environment.

"Climate change is reshaping the Arctic environment and creating new opportunities as well as new risks," Anderson said. "As more vessels, infrastructure and nations become active in the region, there is a growing need for reliable systems that can help maintain awareness of what is happening across these enormous areas."

Anderson, who also holds an Honorary Professorship at University College London, said tracking activity across the Arctic's vast and remote waters calls for technologies that can monitor large areas continuously and deliver timely information to decision-makers.

Several countries already operate HF radar for defence, maritime surveillance and ocean monitoring. These long-range systems transmit high-frequency radio waves that reflect off the Earth's upper atmosphere, allowing them to detect aircraft and ships far beyond direct line of sight.

Compared with many other sensing systems, HF radar can observe very large areas, operate continuously and deliver information in near real time.

Anderson identifies several potential Arctic applications for the technology, including detecting and tracking ships, mapping ocean surface currents and monitoring sea conditions.

Emerging research also indicates HF radar may be able to distinguish between different types of sea ice. It may also be able to estimate key ice properties, such as thickness and the size of individual pieces of ice, known as floes.

"Understanding the location, movement and nature of sea ice is critical for safe and effective operations in the Arctic," Anderson said. "HF radar has the potential to provide information that is difficult to obtain using existing systems, particularly over very large areas."

Communications could also benefit. Satellite coverage and environmental conditions both pose difficulties in the Arctic, where radio wave behaviour is unpredictable, and HF radar systems may give operators a more reliable communication tool.

Anderson cautioned that HF radar should not be treated as a stand-alone solution. He sees it instead as one part of a broader network of sensors and monitoring technologies.

"No single technology can do everything," he said. "The greatest value comes when information from multiple systems is combined. HF radar can add unique insights that strengthen the overall picture and support better operational decisions."

CONTACT: https://adelaide.edu.au/about/school/physics-chemistry-earth-sciences/