It is a quiet retreat with enormous consequences: Starting June 30, the U.S. Department of Defense will cease sharing its satellite data with scientists and weather services - right in the middle of a hurricane season that experts say may be more unpredictable than ever. What sounds like a technical footnote is in fact a fundamental disruption to the global early warning architecture. For decades, U.S. military data was considered irreplaceable - not just for storm analysis, but also for observing sea ice, climate development, and glacier dynamics. Now, that data source falls silent. And no one knows exactly why. "I was surprised - given how important this data is for hurricane forecasting and monitoring phenomena like Arctic sea ice," says Brian Tang, a meteorologist at the University at Albany. For decades, the Fleet Numerical Meteorology and Oceanography Center of the U.S. Navy had processed raw data from military satellites and passed it on to civilian agencies like the National Hurricane Center. But that is now over. The satellites will remain operational - but exclusively for internal use by the Department of Defense. The civilian world will be left in the dark.
Officially, the reason given is "cybersecurity concerns." What exactly lies behind that, no one will say. The Navy remains silent. The Space Force, which operates the satellites, points out that the decision is not due to budget cuts. For researchers, it means uncertainty. Most will now rely on alternative sources - such as a Japanese satellite instrument made accessible through a NASA cooperation agreement. But switching over takes time, calibration, and staff. "We thought we had until September. Now we have only the weekend," laments Mark Serreze, director of the National Snow and Ice Data Center. Especially bitter: In 2025, both the Arctic and Antarctic are experiencing historic lows in sea ice. Data gaps at this moment are not a mere inconvenience - they are a blow to the heart of climate research. The impact on hurricane monitoring is even more serious. Unlike with long-term climate trends, this is a matter of life and death - in real time. "This data is like an MRI for storms," explains Tang. It shows whether an eye is reforming, whether a storm is gaining strength, whether evacuations are needed. During Hurricane Erick, which hit Mexico in June, experts were able to detect the storm's rapid intensification early thanks to Pentagon data - computer models had not predicted it. Such early warnings may be missing in the future. And this at a time when tropical storms are escalating faster than ever - often just before landfall.
NOAA, which oversees the National Hurricane Center, is presenting a calm front. It has "fully capable independent data sources" and can continue to provide "world-class forecasts," says the communications director. But internally, concern is growing. Because the truth is: no sensor watches a specific storm area around the clock. Only the multitude of satellites - including military ones - has so far made a seamless real-time picture possible. If one source falls away, blind spots appear. And those blind spots can be deadly. What remains is the sense of a policy shift flying under the radar. While the U.S. had outwardly demonstrated power and cooperation through weather data, the Pentagon is now choosing isolation. In a world that needs more climate information than ever before, a curtain is being drawn shut. Without necessity. Without explanation. And with unforeseeable consequences for science, safety - and for all those who must face the next storm.
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