The United States will retire more than 900 sensors from the Ocean Observatories Initiative this week, stripping away a network that spans the coasts of Oregon, Washington, Alaska, North Carolina and Greenland. Canadian researchers, led by Kate Moran of Ocean Networks Canada, call the move a “shock” that will leave a data gap just as an El Niño event approaches the Pacific for marine research.

The sensors collected real‑time temperature, current, sea‑level and seismic measurements essential for fisheries management, emergency planning and climate‑change studies. Their removal coincides with a budget proposal that slashed NSF funding by more than half, a trend that began under the Trump administration. Researchers warn that satellite data cannot replace subsurface observations, especially in low‑oxygen zones in critical habitats.

Without the Pacific Northwest array, scientists lose the ability to track long‑term oceanic signals that differentiate natural variability from climate impacts. Ed Dever of Oregon State University calls the loss “crippling,” noting that only surface metrics remain. The remaining cabled observatory off Washington will still feed earthquake and tsunami alerts, but the broader monitoring gap persists for coastal communities.