Over-the-Horizon Radar Gaps Leave Arctic Approaches Unmonitored

The United States and Canada rely on the North Warning System (NWS) — a chain of 47 long-range and 6 short-range radar stations stretching across the Arctic from Alaska to Labrador — to detect airborne threats approaching from the north. This system replaced the DEW Line in the 1980s and was designed to detect Soviet bombers flying at medium-to-high altitudes. It was never designed to detect cruise missiles, hypersonic glide vehicles, or low-altitude drones, all of which are now primary threat vectors from Russia and potentially China via Arctic routes. The gap matters because the Arctic is no longer a frozen buffer zone. Russia has reactivated and expanded its Arctic military bases, deployed MiG-31 interceptors carrying Kinzhal hypersonic missiles, and tested submarine-launched cruise missiles from under Arctic ice. A cruise missile flying at 50 meters altitude and Mach 0.8 would pass below the NWS radar horizon and reach Canadian or U.S. population centers with less than 30 minutes of flight time from detection (if detected at all). NORAD has publicly acknowledged that the North Warning System has 'significant capability gaps' against modern threats. This persists because Arctic radar modernization is a bilateral Canada-U.S. responsibility under NORAD, and the two nations have struggled to agree on cost-sharing, technology selection, and timeline. Canada committed CAD $38.6 billion to NORAD modernization in June 2022, but actual radar site construction in the Arctic faces extreme logistical challenges — no roads, permafrost instability from climate change, and construction seasons limited to 8-12 weeks per year. The physics of over-the-horizon radar (OTH-R) also impose fundamental limitations: ionospheric propagation is unreliable at high latitudes where geomagnetic storms disrupt the ionosphere multiple times per month.