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.
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.