In the far north, where the forests of Alaska and Canada stretch across the Arctic and boreal regions, climate change is unfolding at an accelerated pace. These regions are warming two to four times faster than the global average, putting immense pressure on ecosystems that absorb CO2 and help slow climate change. Through photosynthesis, vast expanses of vegetation naturally pull carbon from the atmosphere and sequester it in their biomass, acting as a buffer against climate change. However, as climate-related disturbances like wildfires and drought intensify, these ecosystems may shift from carbon sinks to carbon sources, disrupting the delicate global carbon balance. Understanding exactly how much carbon these ecosystems store or release is crucial for climate mitigation efforts, but getting accurate measurements is a challenge.
Two new papers aim to improve how scientists measure biomass across these regions. Led by University of Utah biologists Wanwan Liang and Jon Wang, one paper evaluates the accuracy of existing satellite-based datasets, while the other introduces a new biomass map that captures 40 years of ecological change in unprecedented detail. The research emerged from the Arctic-Boreal Vulnerability Experiment (ABoVE), a NASA-funded, 15-year field research campaign to understand ecosystem change in northern high latitudes.
Making sense of remote-sensing data is a complex task. The first study, published in Environmental Research Letters in March 2026, examines the growing number of satellite-based datasets used to map aboveground biomass across Arctic and boreal North America. As the number of datasets has grown, so has confusion about their accuracy and intended use. Different maps often produce different answers, depending on their structure, data sources, and landscape coverage. To address this 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.
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. Spanning from 1984 to the present, the map captures changes at a resolution of 30 meters, roughly the size of a baseball diamond. This level of detail allows researchers to detect not only large disturbances like wildfires but also smaller-scale changes such as logging or land conversion.
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 identify the forces driving those changes, be it drought, fire, human activity, warming temperatures, or rising atmospheric CO2 concentrations. This matters because Arctic and boreal forests are potential buffers against climate change. As temperatures rise, scientists have hypothesized that these ecosystems could absorb more carbon, helping offset emissions from fossil fuels. But the reality is far more complex. The same warming that can stimulate plant growth can also increase wildfire frequency and intensity, insect outbreaks, and drought stress, factors that boost forest mortality and release carbon back into the atmosphere.
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, making decision-making harder. Beyond policy, 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. In contrast to some private-sector efforts that restrict access to carbon data, Liang and Wang's project aims to make information transparent and usable for scientists, policymakers, and the public.
Personally, I find this research particularly fascinating because it highlights the delicate balance between carbon sinks and sources in the Arctic and boreal regions. The potential for these ecosystems to act as buffers against climate change is immense, but the reality is far more complex. The same warming that can stimulate plant growth can also increase wildfire frequency and intensity, insect outbreaks, and drought stress, factors that boost forest mortality and release carbon back into the atmosphere. This raises a deeper question: How can we best manage these ecosystems to maximize their carbon sequestration potential while minimizing the risks of releasing stored carbon back into the atmosphere?
In my opinion, the development of high-resolution biomass maps is a crucial step forward in our understanding of these ecosystems. By tracking changes in biomass over time, scientists can identify the forces driving those changes and develop more effective strategies for managing these ecosystems. However, it is also important to recognize the limitations of these maps and the challenges of accurately measuring carbon sequestration and release. As we continue to develop new technologies and methods for monitoring these ecosystems, it is essential to remain critical and reflective, constantly questioning our assumptions and seeking to improve our understanding of these complex systems.
