Climate Models Missing Key Emissions from Nature, Researchers Warn

Climate models are failing to account for significant emissions from natural ecosystems, according to a new study published by leading climate researchers. The study highlights that these omissions could hinder global efforts to limit temperature rise to below 2 degrees Celsius, a target set by the Paris Climate Agreement.

Understanding Warming-Induced Emissions

For decades, climate scientists have warned about the potential for positive feedback loops in climate systems, where rising temperatures lead to further warming. While many feedbacks, such as sea ice loss, are well understood, emissions from ecosystems like wildfires and wetlands remain poorly represented in climate models. Brian Buma, a climate scientist at the Environmental Defense Fund, states, “If you’re not including all the emissions going into the atmosphere, you’re hamstrung from the get-go.”

The study found that emissions from natural systems could contribute an additional 0.6 degrees Celsius to the rise in global temperatures. This aligns with earlier research suggesting that such emissions could shorten the time frame to exceed the 2 degrees Celsius threshold by 25 percent.

Impact of Ecosystem Changes on Climate

Key sources of warming-induced emissions include wildfires, wetlands, and permafrost, all of which have shown rapid changes recently. Since 2001, global carbon emissions from wildfires have surged by 60 percent. In 2020, researchers noted a spike in atmospheric methane concentrations, partly due to expanding wetlands in Africa and Asia.

• 60% increase in wildfire carbon emissions since 2001
• Spike in methane concentration in 2020
• Rapid changes observed in Arctic tundra emissions

In 2024, the Arctic report card indicated that wildfires and permafrost melt transformed the northern tundra from a carbon sink to a source of emissions. This shift is fueled by hotter, drier conditions that promote wildfires and accelerate soil decomposition.

The Need for Comprehensive Climate Models

Despite the growing evidence of warming-induced emissions, climate models have largely neglected this aspect. Of the 11 Earth system models used in the most recent IPCC assessment, none accounted for emissions from all major sources, including wildfires and wetlands. The modeling challenges stem from a lack of data from remote regions and the complexity of accurately predicting ecosystem responses to warming.

Benjamin Poulter, lead scientist at Spark Climate Solutions, emphasizes that “the longer we go without taking these emissions into account, there’s just going to be a bigger gap.” As climate models evolve, incorporating these emissions is crucial for accurate predictions and effective climate policy.