In the far north regions of Earth, where forests stretch across Alaska and Canada, climate change is unfolding at an accelerated pace. 

Arctic and boreal regions are warming two to four times faster than the global average, putting immense pressure on an ecosystem that is quietly helping to absorb CO2 and keep climate change at bay.  Through the process of photosynthesis, these expansive regions of plant life naturally pull carbon out of the atmosphere and sequester it in their biomass.

However, as climate-related disturbances like wildfires and drought increase, parts of this region may shift from sequestering carbon to releasing it, causing shifts in the delicate balance of the global carbon scale. Understanding exactly how much carbon these terrestrial ecosystems store or release is an important piece of the puzzle for climate mitigation efforts, but the analysis is often tricky. 

A new paper by University of Utah postdoctoral researcher Wanwan Liang and Assistant Professor of Biology Jon Wang aims to improve understanding and access to datasets mapping aboveground biomass (AGB) in North American Arctic and Boreal regions. Published in Environmental Research Letters, the paper evaluates the growing number of satellite-based aboveground biomass datasets. “There are so many datasets out there now,” Liang explains, “but there’s very little guidance for users on how to choose among them.”

Remote-sensing technology

One major contributor to the growing  abundance of datasets is the rapid advances in remote sensing technology. Satellites continuously capture images of Earth’s surface, and scientists use those data, combined with field measurements, to estimate forest structure, growth and carbon storage. Because roughly half of plant biomass is carbon, mapping biomass and its change provide a powerful way to track the global carbon cycle.

Yet as the number of datasets has grown, so has confusion about their accuracy and intended use. Different maps often produce different answers, depending on how they are built, what data they use, and the scale they cover. “Two maps can give completely different estimates for the same region,” says principal investigator Wang, “and if you’re not an expert, it’s really hard to know which one to trust.”

To address that problem, Liang and her collaborators conducted a large-scale meta-analysis, comparing nine biomass datasets across North America’s Arctic and boreal regions. Rather than declaring a single “best” map, the study identifies which datasets are most reliable for specific uses, from tracking wildfire impacts to estimating national carbon budgets.

“It’s more like a guide,” Wang says. “Different maps are better for different purposes.”

Pushing science forward collectively

This work represents a collective effort from many researchers, including Wang and Liang, engaged in  a broader, 15-year field research campaign funded by NASA to understand ecosystem change in northern high latitudes. Known as the Arctic-Boreal Vulnerability Experiment (ABoVE), the project brings together scientists from multiple institutions to study how climate change is reshaping forests, soils and carbon dynamics. 

As the NASA ABoVE program comes to a close, NASA held a final “Technical Interchange” meeting in Fairbanks, Alaska, which Wang attended in April 2026. Despite the chilly weather, it was an opportunity to plan several “capstone” synthesis papers for the campaign that summarize the achievements of the ABoVE campaign in advancing carbon cycle science and terrestrial ecology in the northern high-latitudes. It was also a great opportunity for long-time collaborators and colleagues to bid farewell to the program and reflect on boreal ecosystems one more time. 

“The NASA ABoVE project has a very lovely, supportive, and professional big group,” Liang says. “We’re all working for the same program, and we know this study region very well, but we have different backgrounds, so even if I’m not an expert on this, I can reach out to someone within the program who is an expert on that, and we can collaborate.” That collaborative spirit is central to the new paper.

“Instead of competing, we worked together to understand the strengths of each dataset,” Wang said. “It’s really about pushing the science forward collectively.”

Size of a baseball diamond

Alongside the meta-analysis study, Liang also led the development of a new biomass dataset, one of the most detailed of its kind. Built using satellite imagery from the NASA/USGS Landsat program, airborne LiDAR measurements, and extensive forest inventory data from the U.S. and Canadian Forest Services, the dataset tracks aboveground biomass annually across nearly four decades. Wanwan led a paper in the journal Remote Sensing of Environment to describe this dataset that was published last month.

Spanning from 1984 to the present, the map captures changes at a resolution of 30 meters, roughly the size of a baseball diamond. That level of detail allows researchers to detect not only large disturbances like wildfires, but also smaller-scale changes such as logging or land conversion. “Anything happening at 30 meters or larger, we can detect,” Liang said.

The dataset provides a powerful new lens for understanding how northern ecosystems are responding to climate change. By tracking where biomass is increasing or decreasing, scientists can begin to identify the forces driving those changes, whether warming temperatures, increasing atmospheric CO2, drought, fire, or human activity.

This matters because Arctic and boreal forests are often seen as a potential buffer against climate change. As temperatures rise, some scientists have hypothesized that these ecosystems could absorb more carbon, helping offset emissions from fossil fuels, but the reality is far more complex.

“There’s been this idea that northern forests will just keep taking up more carbon as it gets warmer,” Wang says. “But we don’t actually know if that’s true.” In fact, the same warming that can stimulate plant growth can also increase wildfire frequency and intensity, insect outbreaks, and drought stress, factors that increase forest mortality and release carbon back into the atmosphere. “If plants start to die, they stop absorbing carbon,” Liang explained. “And as they decompose, they release CO₂. That would accelerate climate change.”

The uncertainty has real-world implications. Governments rely on carbon estimates to inform climate policy and report greenhouse gas inventories. In Canada, for example, national carbon accounting influences how emissions targets are set and evaluated.

“When different datasets give different answers, it creates a lot of uncertainty,” Wang said. “And that makes decision-making harder.”

Beyond policy, the data have practical applications in wildfire planning, forestry management, and ecosystem conservation. High-resolution biomass maps can help estimate how much carbon might be lost in a fire, identify high-risk areas, and guide land-use decisions.

Importantly, Liang and Wang emphasize that their work, and the datasets they analyze, are publicly available. In contrast to some private-sector efforts that restrict access to carbon data, this project aims to make information transparent and usable for scientists, policymakers, and the public. “This is taxpayer-funded science,” Wang said. “We want people to be able to use it.”