In his article for the Guardian, Patrick Greenfield writes about the worrying find that sudden collapse of carbon sinks has not been factored into climate models. The scientists say that their collapse, could rapidly accelerate global heating.
A team of international researchers have published their preliminary results, revealing that in 2023 (the hottest year on record) the amount of carbon absorbed by land – through forest, plants and soil, collapsed – meaning they absorbed almost no carbon. In addition, the scientists point to warning signs at sea caused by the faster melting of Greenland’s glaciers and Arctic ice sheets causing disrupting to the Gulf Stream, slowing the rate at which oceans absorb carbon. The melting sea ice is exposing crucial algae-eating zooplankton to more sunlight, preventing them from their feeding migrations of microscopic algae on the ocean surface from the ocean floor, which absorbs millions of tonnes of carbon from the atmosphere each year.
According to the scientists, these critical signs of instability of land and ocean ecosystems show the fragility of the earth’s carbon store and carbon uptake capacity. Reaching net zero is impossible without nature. The rapid land sink collapse seen in 2023 has not been factored into most climate models, explain the researchers- which if it continues, raises the prospect of rapid global heating beyond what those models predicted.
“This stressed planet has been silently helping us and allowing us to shove our debt under the carpet thanks to biodiversity,” explained Rockström to Greenfield. “We are lulled into a comfort zone – we cannot really see the crisis.”
The Amazon basin is under stress due to record-breaking drought with its rivers at an all-time low, the tropical rainforests in south-east Asia have become a net source of emissions in recent years due to expansive agriculture, emissions from soil are expected to increase by as much as 40% by the end of the century – putting into question our reliance of carbon sinks to achieve net zero. How the world’s natural carbon sinks will behave in future has therefore become more difficult to predict.
A must read: Trees and land absorbed almost no CO2 last year. Is nature’s carbon sink failing? by Patrick Greenfield, Guardian.