Tropical ecosystems and rainforests under drought: Aerial view of Lake Anama in Manaus, Brazil, in October 2005 after a month-long drought had lowered the level of parts of the Amazon River by several metres. (Photograph: Keystone)
ETH Zurich News
Droughts increasingly reduce CO2 uptake in the tropics
ETH Zurich researchers have found that droughts and land water variability have had an increasing effect on the carbon cycle in the tropics over the last sixty years. Most climate models fail to capture this observation. This could mean that terrestrial ecosystems could absorb less CO2 than expected in their role as carbon sinks in the future.
MONGABAY
Drought cycles erode tropics’ ability to absorb CO₂, study finds
A recent study finds that tropical carbon sinks have become increasingly vulnerable to water scarcity since 1960, and are consequently less able to absorb carbon dioxide.
These findings suggest that tropical ecosystems are less resilient to climate change than previously thought.
While the study doesn’t necessarily make projections for the future, the findings suggest that an acceleration of climate change, which is very likely to bring more drought, could further limit the ability of tropical ecosystems to absorb carbon dioxide, which, in turn, would worsen climate change.
Salzburger Nachrichten
Rainforest absorbs less CO2 due to droughts
Denn Pflanzen stellen die CO2-Aufnahme ein, um Wasserverluste zu vermeiden, wenn es zu heiß und trocken wird. Zudem gibt es bei heiß-trockenen Bedingungen auch mehr Waldbrände, die zu CO2-Verlusten in der Biosphäre führen. Kommen solche Bedingungen also öfter vor, könnte der Wald laut den Forscherinnen und Forschern weniger klimaschädliches CO2 aufnehmen. Die Klimaerwärmung würde dadurch verstärkt.