LONDON: Earth’s forests, oceans and soils are showing growing signs of strain under the pressure of rising human-generated carbon emissions, raising concerns about the ability of natural ecosystems to continue providing one of the planet’s most important climate buffers.
For decades, natural carbon sinks have absorbed a substantial share of carbon dioxide released by human activities, helping slow the accumulation of greenhouse gases in the atmosphere. But increasing temperatures and ecosystem disruption are putting that capacity under mounting pressure.
Climate change is intensifying wildfires, droughts and marine heatwaves, all of which can weaken ecosystems’ ability to capture and store carbon. At the same time, deforestation and land degradation are reducing the capacity of forests and soils to function as long-term carbon stores.
The resulting concern is that the amount of carbon entering the atmosphere could increasingly outpace the amount being removed by natural systems. This would leave a larger proportion of human-generated emissions in the atmosphere, adding to global warming.
Forests such as the Amazon rainforest are particularly important because they store vast amounts of carbon while supporting exceptional biodiversity. When forests are degraded or destroyed, their capacity to absorb carbon can decline, while fires and decomposition can release previously stored carbon back into the atmosphere.
The oceans face similar pressures. Warmer waters and marine heatwaves can affect the biological and physical processes that allow the ocean to absorb and store carbon dioxide, potentially weakening another major component of Earth’s natural climate-regulation system.
Scientists have increasingly warned that natural carbon sinks should not be treated as a substitute for cutting fossil-fuel emissions. Their ability to absorb carbon is neither unlimited nor guaranteed, particularly as climate change itself damages the ecosystems on which that service depends.
The situation highlights the importance of rapid and sustained reductions in greenhouse-gas emissions, alongside efforts to protect and restore forests, wetlands, soils and marine ecosystems. Maintaining healthy natural carbon sinks can complement emissions reductions, but cannot replace them.
The growing pressure on nature’s carbon-storage systems is therefore another warning that climate action must address emissions at their source while strengthening the resilience of the ecosystems that help regulate the global climate.
