“Shocking Shift: One-Third of the Arctic’s Carbon Reservoir Turns Emission Source, New Research Uncovers”

A significant portion—one-third—of the Arctic’s tundra, woodlands, and wetlands have turned into a source of carbon emissions, according to a recent study, as climate change disrupts centuries of carbon retention in certain areas of the frozen north.

For numerous years, Arctic terrestrial ecosystems have served as a deep-freeze for the planet’s carbon, preserving extensive quantities of potential emissions trapped in permafrost. However, ecosystems within this region are gradually becoming contributors to global warming by releasing increasing levels of CO₂ into the atmosphere due to rising temperatures, as concluded by a newly published study in Nature Climate Change.

According to the analysis, over 30% of the area was identified as a net source of CO₂, increasing to 40% when emissions from wildfires were factored in. Utilizing monitoring data from 200 research locations from 1990 to 2020, the study illustrates how rapid warming is reshaping the Arctic’s boreal forests, wetlands, and tundra.

“This is the first time we are witnessing such a large-scale shift cumulatively across the entire tundra. That’s quite significant,” remarked Sue Natali, a co-author and principal researcher of the study at the Woodwell Climate Research Center.

The transition is happening even with the Arctic becoming more verdant. “In a region where I work in interior Alaska, as the permafrost thaws, plant growth increases which can sometimes result in a temporary rise in carbon storage,” noted Natali. “However, the permafrost keeps thawing and the microbes take over. There is a vast repository of carbon in the ground, and phenomena like ground subsidence can be visually observed. The alterations in the landscape are evident,” she stated.

The study arises amid escalating apprehensions among scientists regarding the natural mechanisms that maintain the Earth’s climate, which are also being impacted by the increasing temperatures. Collectively, the Earth’s oceans, forests, soils, and other natural carbon reservoirs absorb roughly half of all anthropogenic emissions, yet indications suggest that these sinks are becoming strained.

The Arctic ecosystem, which encompasses Siberia, Alaska, the Nordic nations, and Canada, has been storing carbon for millennia, contributing to the cooling of the Earth’s atmosphere. According to the researchers, the carbon cycle in the area is beginning to shift in a warming climate and necessitates improved monitoring.

Anna Virkkala, the primary author of the study, stated: “A considerable amount of carbon resides in the Arctic soils. It constitutes nearly half of the global soil carbon pool. This quantity far exceeds what exists in the atmosphere. There’s a vast potential reserve that should ideally remain in the ground.”

“As temperatures rise, soil temperatures also increase. Within the permafrost, the majority of the soils have remained fully frozen year-round. However, as temperatures rise, more organic material becomes available for decomposition, leading to carbon being released into the atmosphere. This phenomenon is known as the permafrost-carbon feedback, which is the primary driving force here.”

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