New study finds natural climate feedbacks could amplify global warming by up to 30%

A hidden multiplier in the climate system

A new study has found that greenhouse gases released from natural systems as the planet warms could amplify human-caused global heating by 20% to 30% by the end of this century. The research examines emissions from thawing permafrost, wetlands, fresh water and wildfires—four systems that can release additional methane or carbon dioxide after rising temperatures disturb stored carbon.

The Guardian reported that this extra warming could add about 0.2C under a rapid emissions-reduction scenario and as much as 0.4C under a higher-emissions pathway. Those increments are globally consequential: small changes in average temperature can materially alter the probability and severity of heatwaves, droughts, floods, fires and ecosystem losses. The article includes photographs documenting wildfire and permafrost conditions rather than a logo or title-only cover.

Why existing projections may be too optimistic

Climate models already account for many interactions between the atmosphere, oceans and land. The new research argues, however, that policy-facing projections do not yet fully capture emissions generated when natural carbon stores are destabilised. Thawing frozen ground can release long-trapped gases; warmer wetlands and lakes can emit more methane; and drying forests can lose carbon through fire, decay and reduced capacity to absorb future emissions.

This does not mean runaway warming is inevitable, nor does it reduce the importance of government action. The study finds that rapid cuts to fossil-fuel emissions would limit the additional heating produced by these feedbacks. The size of the multiplier therefore still depends partly on choices made by governments, industries and energy consumers. Faster reductions leave natural systems less severely disrupted and reduce the carbon released back into the atmosphere.

The finding arrives as the UN prepares for overshoot

The research lands shortly after the UN Environment Programme concluded that global temperatures are likely to cross 1.5C above pre-industrial levels within the next few years. UNEP’s most optimistic pathway peaks near 1.8C before temperatures decline, while less ambitious scenarios produce greater and longer-lasting overshoot. The agency says every additional fraction of a degree increases risks to health, food security, water supplies, ecosystems, infrastructure and low-lying communities.

Together, the study and the UN assessment sharpen the policy question facing leaders: carbon budgets and national targets may need to incorporate a larger contribution from destabilised natural systems. Governments are due to gather for the UN Climate Summit on September 23, where energy transition, adaptation, methane and climate finance are on the agenda. What matters next is whether scientific modelling bodies validate the study’s estimated range and whether governments adjust emissions pathways, resilience spending and methane policy accordingly.