This month, our most recent permafrost study came out in Frontiers in Environmental Science. Because of the Utah Lake lawsuit and general craziness, I wasn't able to get a press release together before the study was published, but I thought I'd release it now. I'd love to hear your thoughts and questions.
Permafrost affects only 10% of the Earth’s surface—mainly in the far north. However, changes in these distant regions should concern all of us. According to a study published this week in Frontiers in Environmental Science, rapid warming is causing cascading changes in permafrost regions that are threatening biodiversity, the stability of global climate, and the wellbeing of over 1.5 billion people.
A team of 33 international experts summarized more than 200 recent studies about how climate change and permafrost are interacting. The science and policy experts focused on four key permafrost regions: the Arctic Ocean, the Boreal Forest, the Arctic Tundra, and the Tibetan Plateau. Together called the permafrost domain, these areas are especially vulnerable to climate change because of their dependence on ice. This is a problem because they are warming three-times faster than the global average, with many regions already 2 to 5 degrees Celsius warmer than before the Industrial Revolution.
“This is one of the biggest and most complex parts of the Earth system, and it’s hard to grasp how fast things are changing,” said lead author Ben Abbott, a professor at Brigham Young University, U.S.A. Abbott said, “The permafrost domain regulates the Earth’s energy balance and affects ocean circulation and habitat for people and wildlife worldwide.”
Arctic researcher Sarah Godsey digs a snow pit to measure water and gas content beneath the surface. Loss of snow cover and sea ice are resulting in rapid warming in many permafrost regions. North Slope of Alaska, 2011.
The study estimates that the permafrost domain contains between 2.5 and 3 trillion tons of organic carbon; more than all of Earth’s other life, soil, and atmosphere combined. As this plant and animal material begins to decompose, microorganisms produce CO2, CH4, and N2O, the three most important long-lived greenhouse gases. Under more extreme warming scenarios, permafrost rot could produce hundreds of billions of tons of emissions.
“Ignoring permafrost is essentially like leaving a major greenhouse gas emitting country like the United States out of climate negotiations, which is not a good idea,” said study author Susan Natali from the Woodwell Climate Research Center in a TED talk on the topic earlier this year. Another study author Jens Strauss from the Alfred Wegener Institute said, “Today the permafrost regions are already releasing nearly the same amount of greenhouse gases as Germany’s annual emissions.”
The study reveals that dramatic changes are progressing decades faster than expected. Sea ice and snow cover have plummeted, storms have intensified, soils and coastlines are eroding, and wildfires are burning through the winter.
However, the experts insist that a “time bomb” scenario of runaway greenhouse gas release is unlikely. Instead, they explain that the faster we reduce emissions, the more the permafrost domain remains stable and healthy. Rather than an abrupt belch, greenhouse gas release from the permafrost domain could last hundreds of years and occur across millions of square kilometers. This results in a slower climate feedback but also makes it extremely difficult to stop.
As important as permafrost climate feedbacks are, the experts emphasize that the permafrost domain is more than just “a pile of greenhouse gas precursors.” It is home to tens of millions of Indigenous and immigrant people, and it supplies water and resources to billions more, largely around the Tibetan Plateau.
Natali said, “Right now across the Arctic, people are having to make extremely difficult decisions about where and how to live in order to protect themselves and their families from the hazards of climate change.” The authors conclude that permafrost preservation is both a practical and a moral issue. “People living in the permafrost domain have done very little to cause climate change, but they’re particularly hard hit by it,” said Strauss.
A permafrost exposure near the Arctic Ocean with exposed, Pleistocene-aged ice. North Slope of Alaska, 2013.
In line with last year’s State of the Cryosphere report, this study concludes that current climate mitigation targets are inadequate. “We sometimes treat 1.5 degrees as a safe level of warming, but that is not true for permafrost,” said Abbott. “Right now, we’re at 1.2 degrees globally, and the permafrost domain is already in full-on transition. The energy choices we make over the next decade could either open pathways toward recovery or lock us into a future of loss and degradation.”
The authors propose that policy action is needed both within and beyond the borders of the permafrost domain. They advocate for the rapid reduction of fossil fuel use globally and support for Indigenous and immigrant permafrost communities who are already dealing with the consequences of climate change.
On the question of how to reduce greenhouse gases the fastest, the authors provide two recommendations. They write, “recent breakthroughs in renewable energy production, transmission, and storage now allow much faster decarbonization than previously believed possible,” and call for a global commitment to abrupt decarbonization. At the same time, they warn that many geoengineering “climate hacks” are not viable and could cause unintended consequences in the permafrost domain and beyond. Strauss said, “We don’t want to demonize all these approaches, but we need to be realistic about potential benefits and possible side-effects.”
Researchers hike back to the Dalton Highway after collecting soil and gas samples to measure the response of permafrost to climate change. The Trans-Alaska Pipeline can be seen in background carrying crude oil for export. North Slope of Alaska, 2010.
Rather than climate mitigation (making things less bad), the authors propose “climate restoration”—a return to pre-industrial climatic conditions. They claim this is possible through the rapid rollout of renewable energy, the conservation of intact ecosystems, and the development of negative emissions technologies. Abbott said, “We’ve got a choice between fossil fuel use and the continued existence of permafrost ecosystems. If we pick wrong, the consequences for human rights, biosphere integrity, and global climate will be severe.”
This study was supported by the U.S. National Science Foundation and Department of Energy. The work grew from two international research efforts: The Permafrost Carbon Feedback Action Group and the Permafrost Carbon Network—an international research network funded by half-a-dozen U.S. and international agencies and organizations.
Figure 1 from the publication showing the extent of the permafrost domain. The extent and example futures of the permafrost domain (A) Our definition of the domain includes marine and terrestrial regions substantially affected by perennial frozen material, including oceans and seas above 50°N, subsea permafrost on the continental shelves, Arctic tundra, Boreal forest, and Alpine permafrost. The figure shows potential permafrost futures for (B) a rapid decarbonization scenario and (C) a continued fossil energy scenario. Panel B depicts: 1. Resilient biological communities in marine, coastal, and terrestrial environments, 2. Persistence of sea ice, especially crucial multiyear and landfast ice, 3. Maintenance of net greenhouse gas uptake in the permafrost domain, 4. Recovery of permafrost and a shallow active layer, and 5. Preservation of human cultural activities and infrastructure. Panel C depicts: 6. Expansion of fossil fuel extraction and marine navigation, 7. Disruption of food webs, migrations, and biological communities on sea and land, 8. Accelerated coastal erosion, aquatic and marine primary productivity, ocean acidification, and erosion of terrestrial material, including pollutants, 9. Transition to net release of greenhouse gases (CH4, N2O, and CO2), 10. Extensive permafrost degradation, including active-layer thickening and lake formation and draining, 11. Intensifying terrestrial disturbances including wildfire, hydrological extremes, thermokarst, vegetation shifts, and invasive species, 12. Profound disruption of human culture and infrastructure.
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