Along the South Pacific right now, a small yellow cylinder is going down. It will go down to 2,000 meters, take readings of the temperature and salinity, and then rise again and send a signal to a satellite. This takes place in every ocean basin on Earth thousands of times every day. A lot of people have never heard of it. It turns out that most governments don’t know how much they depend on it.
That network, which was carefully built over decades with mostly American money and initiative, is now in danger. Not from an enemy power. Not because of a problem with technology. Due to budget cuts.
The Global Ocean Observing System, or GOOS, is one of those quietly amazing things that people don’t even realize they depend on. Research ships are going from the surface to the seafloor along deep cuts. Moored buoys are keeping an eye on the tropical waters for the first signs of a cyclone. Real elephant seals are carrying tiny sensors under the polar ice to water that no other instrument can reach. It’s a strange, big, and really impressive operation. And the United States has always been its strongest link.
A study in Nature Climate Change put a number on how important that role is. If the United States stopped contributing to GOOS, there would be 163% more mistakes when measuring how fast the oceans are warming up. To give you an idea of how bad that is, think about losing 80% of all ocean data by accident. There are a lot of American instruments in places where no one else has put them. This is because of geography. It took generations to build up the coverage in a way that makes sense.
You can’t help but notice that this comes at a very bad time. There have been rumors going around for a while that NOAA and the National Science Foundation might be cut. The rumors are specific enough to worry oceanographers who have spent their careers watching this system grow. In those places, there’s a quiet fear. Not the kind that makes the news, but the kind that needs to be looked at by experts and is written in papers that sound very important.
What this network does every day is something that gets lost in the debate. It’s not just “climate monitoring,” which sounds vague and far away. The weather forecasts that people check every morning are based on these observations. Predictions of how bad a hurricane will be—the ones that decide if a city on the coast has to evacuate—depend on knowing how hot the ocean is hundreds of meters below the surface, not just what it looks like from space. Tools like Pangu-Weather and GraphCast, which have been in the news lately for their AI-based weather forecasting systems, depend on this stream of observations in every way. AI doesn’t take the place of eyes in the water. It uses up their output.
There is a false belief that needs to be addressed: models are now good enough to fill in the gaps. They haven’t. An ongoing process known as “data assimilation” moves all forecast models closer to real-world measurements. This is true for both traditional and AI-based models. If you take away the observations, the model will drift. When extremes are getting worse and ocean patterns are changing, it’s not as good to use past data as a guide. A note that wasn’t made is now gone. Stopping to look in 2025 means you can’t figure out what the ocean was doing then.
It’s really not clear if it’s too late to change course. It is possible for Europe and Asia to make bigger contributions, and people are talking about what a more distributed system might look like in a careful, diplomatic way. China is putting money into keeping an eye on the oceans, but not yet on the scale that is needed. Some researchers are cautiously optimistic that there could be a model of leadership after the United States. Some people aren’t so sure.
A smooth transition is becoming less likely as time goes on. Once ocean data gaps appear, they stay open for years. These things are still in the water. For now.
