As of today, in season, building toward peak (~August 1). Earth Exhibit tracks the live conditions and flags it the moment it is on.
Aoshio ("blue tide") is a striking daytime phenomenon in Tokyo Bay where the water turns a milky, opaque turquoise.
Sustained northeasterly winds push surface water offshore and draw up oxygen-depleted bottom water rich in hydrogen sulfide; as that sulfide meets oxygen near the surface it forms fine colloidal sulfur particles that scatter sunlight, tinting the bay pale blue.
It typically appears in late summer and autumn and is a sign of severe oxygen depletion that can trigger fish and shellfish die-offs along the shore.
Where to see it
A taste of where to see it. The full map, exact coordinates and the best timing for each spot live in the app.
| Viewing spots |
|---|
| Odaiba Seaside Park (Oedo Kaihin) |
| Shin-Kiba / Tokyo Gate Bridge shoreline |
| + 2 more spots, with exact coordinates and timing, in the app → |
This is the short version
This page shows a taste. The app has the full list of where to see this, the exact timing, and live conditions for 1,000+ natural phenomena worldwide, so you know the moment one is genuinely worth the trip.