The Amazon basin and the European Union
A river's scale is not defined by channel length alone. The Amazon drains an area larger than the entire European Union. Its basin is comparable in size to a continent.
A river is a line on a map, so its 'size' is its length. Surely even the biggest river can't rival the European Union in area.
The Amazon basin includes the whole area that drains into the river and its tributaries. It covers about 7M km², while the European Union's 27 countries cover about 4.23M km².
A river can be described by channel length, which is about 6,400 km for the Amazon. Another measure is its drainage basin, the entire land area whose rainfall flows into the river. Basin area reveals the reach of the whole river system.
Placed over a map of Europe, the Amazon basin would cover the European Union with a wide margin. The comparison replaces the simplified image of a river as a thin line with the scale of the land that feeds it.
Set the slider to your intuition: how many times bigger (or smaller) the Amazon basin is than the whole European Union. Then reveal the truth.
How many times bigger is the Amazon basin than the whole European Union?
Set the slider to the value you consider most likely.
- River length and drainage-basin area describe two different aspects of scale.
- A single river's catchment can be larger than whole blocs of countries.
- The Amazon carries about a fifth of all the fresh water rivers discharge into the oceans.
Amazon basin questions and answers
It is the entire land area from which rainfall and meltwater flow into a river and its tributaries. The Amazon basin spans parts of eight South American countries and French Guiana.
About 7M km², or roughly 40 percent of South America. That is more than the European Union's area of about 4.23M km².
That is disputed because the result depends on the chosen source and measurement method. Estimates commonly range from 6,400 to 7,000 km. The Amazon is nevertheless the largest river by drainage-basin area and water discharge.