Bluegraph rebuilds NOAA buoy data as a live 3D map of wave height and period

A live 3D atlas of NOAA's ocean sensors

Bluegraph, a project that reached the front page of Hacker News, takes the public observations streamed by NOAA's National Data Buoy Center and rebuilds them as an interactive 3D visualization. The data covers the buoys, coastal stations, tide gauges and estuary stations operated by NOAA and its partners — a footprint the project describes as spanning two oceans, the Caribbean and the Great Lakes, from the Bering Sea down to Samoa.

According to the project's site, 113.7 million data points have been collected since April 2025. At the time of the Hacker News listing, the most recent observation was stamped 29 September at 02:50 UTC, and 700 of the 715 tracked stations had reported within the previous three hours.

Reading the scene

The Hacker News listing describes the visualization as rebuilt in 3D from the measured spectra. The site's legend spells out the encodings: each station appears as a column whose height corresponds to significant wave height, while brightness corresponds to the dominant wave period on a scale of 4 to 16 seconds. Both quantities are standard products of the wave spectra that oceanographic buoys record, so the height and glow of each column trace directly back to what the instruments measured rather than to a stylized wave graphic.

What the network was reporting

The site groups stations into regional clusters and, at the time of the listing, showed a network that was almost fully live. The Great Lakes formed the largest group with 136 stations, 133 of them reporting, and typically calm water — a median significant wave height of 0.2 m and a maximum of 0.6 m in Whitefish Bay, Michigan. Alaska followed with 121 stations, 118 live, a median of 1.6 m and a peak of 3.4 m in the central Gulf of Alaska, over the coldest water on the map at 7–13 °C.

The largest waves anywhere in the snapshot were off western Hawaii: 3.8 m against a regional median of 2.5 m, with all 22 Hawaiian stations reporting. California and the Pacific Northwest both peaked at 3.5 m — at San Nicolas Island and at West Dixon Entrance respectively — while the Gulf of Mexico's 105 stations stayed comparatively flat, topping out at 1.0 m at Satan Shoal, Florida, over water of 28–34 °C. Smaller clusters included the Caribbean and tropical Atlantic (25 stations, peak of 1.7 m northeast of St Martin), the two Eastern Seaboard groups (100 northern stations peaking at 2.7 m off Nantucket, Massachusetts, and 67 southern ones peaking at 1.5 m at a station 350 nautical miles east-northeast of Nassau), the Pacific islands (11 stations, peak of 2.9 m at Aunuu, American Samoa) and four inland-lake stations, the roughest being Lake Winnipeg Narrows in Manitoba at 0.5 m.

All of these figures are a snapshot: they reflect conditions at the moment the page was captured and will differ from what a visitor sees at any given time.

Why it matters

Buoy data is public, but it usually arrives as per-station tables, text feeds or bulk files that hide the spatial picture. By turning 700-plus live stations into a single scene where height and brightness encode the underlying spectral measurements, Bluegraph makes basin-scale patterns legible at a glance: storm-driven swell in the Pacific, flat summer water in the Gulf, cold Alaskan seas, the modest chop of the Great Lakes. It is also a compact demonstration of what open government data makes possible — the sensors, telemetry and archives belong to NOAA and its partners, while the visualization layer is an independent build that anyone with a browser can explore.