Analyzing Terrestrial Carbon Flux Site Distribution Across the Arctic

The Arctic tundra and boreal biomes store large amounts of carbon that have the potential to undergo change as the Arctic is warming two to three times faster than the global average. Understanding carbon fluxes across the tundra and boreal biomes is therefore crucial to understanding how the Arctic is both responding and contributing to climate change. However, many articles have highlighted the lack of carbon flux data needed to fully comprehend the current state of the Arctic carbon balance. Over the past few decades, a growing network of terrestrial ecosystem CO2 flux sites has been established across the Arctic. However, it is not well known how well these sites cover the different climate, permafrost, and soil organic carbon conditions. We used an existing flux database and gridded datasets to explore and visualize the distribution of sites. Some regions of the Arctic, including Alaska, south-central Canada, and northern Europe, are well represented by the current sites. In contrast, regions such as northern and eastern Canada, which have high precipitation and carbon-rich conditions, and much of Russia, which has both some of the coldest and warmest mean temperatures across the Arctic, remain under-sampled and not well represented. The lack of data from these areas suggests that the scientific community has a major knowledge gap, hindering our ability to understand and predict the current or future carbon balance of these ecosystems. We highlight particular areas where new site installation would substantially increase representativeness, including eastern Canada, southern Norway, and most of Siberia.