Context
Scientists have raised alarms that deforestation in the Amazon rainforest is weakening the system of “flying rivers” — atmospheric rivers of moisture that carry rain across South America from the Atlantic Ocean. This could intensify droughts across Brazil, Peru, and the Andes, severely impacting agriculture, hydropower, and biodiversity.
Key Highlights
- What are “Flying Rivers”?
- The term describes the invisible air currents carrying water vapor (evapotranspiration) from the Amazon rainforest westward across South America.
- These moisture-laden winds act as “atmospheric rivers”, moving water vapor from the Atlantic Ocean → Amazon Basin → Andes Mountains.
- Trees play a critical role by releasing moisture into the air through transpiration, creating a pump effect that sustains rainfall across the continent.
- Mechanism:
- Moist air from the Atlantic moves inland, rises, and cools over the forest canopy, condensing into rain.
- Forest loss disrupts this cycle: fewer trees mean less moisture release, weakening rainfall systems.
- Deforestation Impact:
- Deforestation and conversion of rainforest into grasslands reduce moisture recycling.
- As per new analysis by Monitoring of the Andean Amazon Project (MAAP) and scientist Carlos Nobre, continued deforestation could push the ecosystem toward a “tipping point”, transforming rainforest into savanna.
- The region’s carbon storage capacity would plummet, worsening climate change.
- Affected Regions:
- Southern Brazil and Northern Bolivia—where deforestation is most severe—are already witnessing longer dry seasons.
- Hydroelectric dams in Ecuador and crops in Peru are under stress due to reduced rainfall.
- Scientific Warning:
- The “flying rivers” phenomenon is weakening rapidly.
- If tree loss continues beyond a threshold, rainfall patterns could collapse permanently, leading to irreversible drought cycles.
- Mitigation Measures Suggested:
- Urgent reforestation and forest protection, particularly in degraded zones.
- Recognition and protection of Indigenous lands, which are most effective in preserving forests.
- Policies aimed at reducing carbon emissions and restoring ecosystem balance.