What is the

Biotic Pump?

The “biotic pump of atmospheric moisture” describes the physical and ecological mechanism that explains how forests attract moisture-laden winds to provide their own water[i]. This is why large continental regions such as Amazonia, the Congo and Siberia remain so wet. This mechanism has substantial wider implications.

The Biotic Pump explains physically how an old-growth forest generates its own rain

Among other things, the biotic pump also explains how declining tree-cover threatens the rainfall and water security of many millions of people worldwide, why climate models fail to capture many attributes of the global climate such as how and why monsoons are abrupt, and how cyclones gain their destructive power.[i]


Moisture added to a region with scarce vegetation is not resilient: the ecosystem simply loses it and remains dry. When the biotic pump is sufficiently active, the ecosystem switches to a wet optimal stable condition. This switch happens even if the initial amount of moisture is sub-optimal. The stronger the biotic pump, the sooner the system returns to the optimum increasing the inflow of atmospheric moisture. 

[i] (Makarieva and Gorshkov, 2009)