Global Warming: Natural Feedbacks Could Boost Warming by 20–30% by 2100

As the planet warms, ecosystems such as wetlands emit more carbon. New projections indicate that these natural feedback loops will significantly amplify climate change by the end of the century.

Vicious Circle

Emissions from fossil fuels are not the sole drivers of the rising global temperatures. A warmer atmosphere will also tend to hold more water vapor, which in turn strengthens the greenhouse effect and intensifies warming.

If our current climate models already incorporate such feedback loops, researchers have specifically studied their ecological forms, which disrupt carbon storage and whose overall impact is underestimated. “For an appropriate response, we must account for all sources of emissions that contribute to warming,” says Christina Schädel of the Woodwell Climate Research Center.

The first involves the thaw of Arctic permafrost, which leads to the decomposition by microbial communities of organic matter trapped for millennia, thereby releasing large quantities of CO2 and methane.

Ecosystems like wetlands emit more carbon as temperatures rise. By 2100, such feedback loops will increase warming by 20 to 30 per cent more than anticipated https://t.co/y35QWjbC2T

— New Scientist (@newscientist) September 10, 2026

The second and third concerns involve wetlands and freshwater bodies, where the decline in dissolved gas concentrations also promotes this process. Finally, the fourth pertains to the progressive drying of soils, which leads to devastating fires and massive greenhouse gas emissions.

An Inevitable Share of Warming

According to the authors of the new study, published in the journal Environmental Research Letters, a substantial portion of this extra warming is now unavoidable because of the delay between when emissions occur and when their effects are felt in temperatures.

Even in a scenario where greenhouse gas emissions were drastically reduced by 2050, the four feedback loops would contribute an additional rise of about 0.4°C by 2100, representing an amplification of warming of 20 to 30%. If emissions were cut starting today, the increase would still reach 0.2°C.

As worrying as these findings are, they primarily highlight the urgency of intensifying efforts to mitigate climate change. It is estimated that the Earth has already warmed by roughly 1.4°C since the start of the industrial era, and the consequences are already being felt, with heatwaves, deadly floods, and historic El Niño episodes.