Coral Bleach Alert Screensaver
The Coral Bleach Alert screensaver reads live sea-surface temperature at named coral reefs worldwide and compares each to its known bleaching threshold, so current heat-stress risk is visible at a glance — key-less, live from Open-Meteo Marine. It's free, runs in your browser, and ESC exits.
Live preview
Press ESC to leave fullscreen. Settings are saved in your browser only.
How the Coral Bleach Alert screensaver works
The saver fetches live sea-surface temperature at a set of named reefs — the Great Barrier Reef, Coral Triangle, Caribbean and more.
Each reef is compared against its known real bleaching-stress threshold.
Reefs at or above threshold glow warning colors; reefs well below stay a calm blue-green.
The panel refreshes on a schedule so risk tracks real conditions as they change.
A worked example
During a marine heatwave the Great Barrier Reef tile might glow amber — sea temperature approaching its bleaching threshold — a real early-warning signal, not a dramatization.
Settings & tips
- Show reef names toggles the text labels.
- Accent recolours the warning glow.
- Thresholds are published bleaching-stress figures, an approximation of the official NOAA product.
Frequently asked questions
- Is this the official NOAA Coral Reef Watch alert?
- No — it's a live approximation using real sea temperature against published bleaching thresholds, not NOAA's official Degree Heating Weeks product.
- Is a key needed?
- No. Open-Meteo Marine is free and key-less.
- Which reefs are included?
- A built-in set of well-known reef systems spanning the Pacific, Atlantic, Caribbean and Indian Ocean.
- Is it free?
- Yes — free, no download, in your browser.