river flow · Brazil
Amazon at Manacapuru
Dry-season minimum discharge
Modelled demonstration series · not observed data
In this basin the river is the highway. When the dry-season minimum drops this far, communities reachable only by boat become unreachable, and fuel, food and medicine stop arriving. River dolphins die in overheated shallows and the visible story becomes wildlife, but the structural story is isolation.
75 years, modelled
Same reading, two normals
| Normal | Mean | σ | Pct | Return |
|---|---|---|---|---|
| 1951–1980 | 74,000 m³/s | −3.20σ | 0.069th | 1 in 1,500 years |
| 1991–2020 | 69,011 m³/s | −3.40σ | 0.034th | 1 in 3,000 years |
Today would be the lowest value in the entire 75-year modelled series. Past the series' standing low of 50,725 m³/s (2023). Nothing about the reading changes between rows — only the yardstick.
The season here
Even the dry-season minimum on the Amazon is a vast flow. The basin's problem is not absolute volume, it is that river level is the road network.
Where this series comes from
MODELLED SERIES — not observed. Parameters set from published Manacapuru gauge dry-season minimum discharge climatology; lognormal transform applied. The 75 annual values are synthesised by the seeded generator.
Every number on this page comes from a modelled series: 75 annual values synthesised by a seeded generator from published climatological parameters for Amazon at Manacapuru. It shows how anomaly reasoning works. It is not a measurement and must not be cited as one.
How to read σ
σ counts standard deviations from this place's own normal. The sigma guide · return periods.
More river flow stations
Open Amazon at Manacapuru on the field →