Scientists uncover isotopic fingerprint of N2O emissions from Arctic tundra

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A new study from the University of Eastern Finland presents, for the first time, the isotopic fingerprint of nitrous oxide produced by Arctic soils. The finding opens new avenues for predicting future trends in atmospheric nitrous oxide as well as in identifying climate change mitigation actions in the Arctic, a region that is particularly sensitive to climate change.

A new study from the University of Eastern Finland presents, for the first time, the isotopic fingerprint of nitrous oxide produced by Arctic soils. The finding opens new avenues for predicting future trends in atmospheric nitrous oxide as well as in identifying climate change mitigation actions in the Arctic, a region that is particularly sensitive to climate change.

Nitrous oxide (N2O) is a powerful greenhouse gas and also the second largest contributor to ozone depletion in the stratosphere. It is produced naturally by soils, with agricultural and tropical rain forest soils being the main sources of N2O to the atmosphere. Until recently, scientists assumed that nitrous oxide emissions were negligible in colder climate regions like the Arctic and sub-Arctic.

This assumption, however, was contradicted by scientists from the University of Eastern Finland a decade ago, when they discovered that bare peat surfaces in permafrost peatlands are releasing high amounts of N2O, despite the general nitrogen limitation of tundra ecosystems. Since then, N2O emissions and their underlying processes have been the object of plenty of research and, also, debate.

In a new study, researchers from the University of Eastern Finland, together with colleagues from the Venezuelan Institute for Scientific Research (IVIC) and the University of California, Berkeley, explore the isotopic composition and potential sources of nitrous oxide emitted by soils in the sub-Arctic tundra. The study explores new frontiers in polar science, and the approach used establishes a legacy of data and methodologies that have the potential to link the Arctic ecosystem with the global N2O cycle.

Read more at University of Eastern Finland

Image: Bare peat surfaces in the discontinuous permafrost zone of the sub-Arctic East European tundra. New research explores the source of unexpectedly high nitrous oxide emissions from such bare peat soils in Arctic tundra. (Credit: University of Eastern Finland Biogeochemistry Research Group)