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Arctic
Blog edited by Sam Carana, with news on climate change and warming in the Arctic due to snow and ice loss and methane releases from the seafloor.
Marine heat waves will become a regular occurrence in the Arctic in the near future and are a product of higher anthropogenic greenhouse-gas emissions, according to a study just released by Dr. Armineh Barkhordarian from Universität Hamburg's Cluster of Excellence for climate research CLICCS. Since 2007, conditions in the Arctic have shifted, as confirmed by data recently published in the journal Communications Earth & Environment. Between 2007 and 2021, the marginal zones of the Arctic Ocean experienced 11 marine heat waves, producing an average temperature rise of 2.2 degrees Celsius above seasonal norm and lasting an average of 37 days. Since 2015, there have been Arctic marine heat waves every year.
A new paper published in the journal Science has warned that melting areas in the Arctic have become 'frontlines for resource extraction', describing it as a 'modern day gold rush'.
Ocean-driven melting of floating ice-shelves in the Amundsen Sea is currently the main process controlling Antarctica’s contribution to sea-level rise. Using a regional ocean model, we present a comprehensive suite of future projections of ice-shelf melting in the Amundsen Sea. We find that rapid ocean warming, at approximately triple the historical rate, is likely committed over the twenty-first century, with widespread increases in ice-shelf melting, including in regions crucial for ice-sheet stability. When internal climate variability is considered, there is no significant difference between mid-range emissions scenarios and the most ambitious targets of the Paris Agreement. These results suggest that mitigation of greenhouse gases now has limited power to prevent ocean warming that could lead to the collapse of the West Antarctic Ice Sheet. The authors use a regional ocean model to project ocean-driven ice-shelf melt in the Amundsen Sea. Already committed rapid ocean warming drives increased melt, regard
Ice-free summers inevitable even with sharp emissions cuts and likely to result in more extreme heatwaves and floods
Antarctica’s sea ice levels are plummeting as extreme weather events happen faster than scientists predicted
Permafrost and glaciers in the high Arctic form an impermeable ‘cryospheric cap’ that traps a large reservoir of subsurface methane, preventing it from reaching the atmosphere. Cryospheric vulnerability to climate warming is making releases of this methane possible. On Svalbard, where air temperatures are rising more than two times faster than the average for the Arctic, glaciers are retreating and leaving behind exposed forefields that enable rapid methane escape. Here we document how methane-rich groundwater springs have formed in recently revealed forefields of 78 land-terminating glaciers across central Svalbard, bringing deep-seated methane gas to the surface. Waters collected from these springs during February–May of 2021 and 2022 are supersaturated with methane up to 600,000 times greater than atmospheric equilibration. Spatial sampling reveals a geological dependency on the extent of methane supersaturation, with isotopic evidence of a thermogenic source. We estimate annual methane emissions from prog
As the Arctic warms, shrinking glaciers are exposing bubbling groundwater springs which could provide an underestimated source of the potent greenhouse gas methane, finds new research published in Nature Geoscience. The study, led by researchers from the University of Cambridge and the University Center in Svalbard, Norway, identified large stocks of methane gas leaking from groundwater springs unveiled by melting glaciers.
Arctic Sea Ice : Forum*Read All About Arctic on ASI Blog – Watch all Graphs on ASI Graphs
The sixth assessment report of the IPCC assessed that the Arctic is projected to be on average practically ice-free in September near mid-century under intermediate and high greenhouse gas emissions scenarios, though not under low emissions scenarios, based on simulations from the latest generation Coupled Model Intercomparison Project Phase 6 (CMIP6) models. Here we show, using an attribution analysis approach, that a dominant influence of greenhouse gas increases on Arctic sea ice area is detectable in three observational datasets in all months of the year, but is on average underestimated by CMIP6 models. By scaling models’ sea ice response to greenhouse gases to best match the observed trend in an approach validated in an imperfect model test, we project an ice-free Arctic in September under all scenarios considered. These results emphasize the profound impacts of greenhouse gas emissions on the Arctic, and demonstrate the importance of planning for and adapting to a seasonally ice-free Arctic in the near
Seafloor landforms reveal that ice sheets can collapse at 600 metres per day.
With the continent holding enough ice to raise sea levels by many metres if it was to melt, polar scientists are scrambling for answers
Here is a model which gives future temps., pH, and productivity for the earths large water masses. In discussions you can download the full article.
Climate change affects the Arctic and sub-Arctic regions by exposing previously frozen permafrost to thaw, unlocking soil nutrients, changing hydrological processes, and boosting plant growth. As a result, sub-Arctic tundra is subject to a shrub expansion, called “shrubification”, at the expense of sedge species. Depending on the intrinsic foliar properties of these plant species, changes in foliar mineral element fluxes with shrubification in the context of permafrost degradation may influence topsoil mineral element composition. Despite the potential implications of changes in topsoil mineral element concentrations for the fate of organic carbon, this remains poorly quantified. Here, we investigate vegetation foliar and topsoil mineral element composition (Si, K, Ca, P, Mn, Zn, Cu, Mo, V) across a natural gradient of permafrost degradation at a typical sub-Arctic tundra at Eight Mile Lake (Alaska, USA). Results show that foliar mineral element concentrations are higher (up to 9 times; Si, K, Mo for all spec
From the seemingly inexorable increase of carbon dioxide in the atmosphere to the rapid growth in green energy
“The geopolitical situation is more difficult now than it was in 2016, but I can’t imagine that it is more difficult than in 1959,” says Brooks. “Antarctica is a space where we can do extraordinary things, and we’ve seen what countries can do when they come together in the face of crisis.” The question is whether or not the size of the climate crisis in Antarctica outweighs the political crisis in the rest of the world.
An international team of researchers have sounded new alarm bells about the changing chemistry of the western region of the Arctic Ocean after discovering acidity levels increasing three to four times faster than ocean waters elsewhere. The team, which includes University of Delaware marine chemistry expert Wei-Jun Cai, also identified a strong correlation between the accelerated rate of melting ice in the region and the rate of ocean acidification, a perilous combination that threatens the survival of plants, shellfish, coral reefs and other marine life and biological processes throughout the planet's ecosystem.
Giant ice sheets, ocean currents and permafrost regions may already have passed point of irreversible change
Russian energy company Rosneft announced the discovery of a massive oil resource in the Pechora Sea with an estimated 82 million tons of oil. A drilling campaign in the Medynsko-Varandeysky area led to the discovery of the field. “During the tests, a free flow of oil was obtained with a maximum flow rate of 220 cubic meters a day,” the company’s statement read on Wednesday, noting that the “oil is light, low-sulfur, low viscosity.” According to Rosneft, the exploratory work in the Pechora Sea confirmed the "substantial oil potential of the Timan-Pechora province on the shelf and served as the foundation for continuing the study and development of the region."
We may lose up to three meters of coastline in the Arctic every year by 2100 if greenhouse gas emissions are not reduced, according to a study published in the journal Nature Climate Change. The authors also warn about bigger waves due to increasing temperatures, making the coastline very vulnerable to further losses due to erosion.
Climate tipping points in the Antarctica, the Arctic and the Amazon are at risk of being reached before or at the current level of global warming of 1.2 degrees Celsius, requiring a “major rethink” of global climate goals and the action necessary to achieve them, according to a recent report.
‘This event is completely unprecedented and upended our expectations about the Antarctic climate system,’ one expert said
As climate crisis allows new maritime routes to be used, sooty shipping emissions accelerates ice melt and risk to ecosystems
The rapid collapses of two ice shelves on the Antarctic Peninsula over the past quarter-century were most likely triggered by the arrival of huge plumes of warm, moisture-laden air that created extreme conditions and destabilized the ice, researchers said Thursday.
A chunk of Antarctic ice that was one of the biggest icebergs ever seen has met its end near South Georgia. Scientists will be studying its effects on the ecosystem around the island for some time.
Cracks and fissures stoke fears of breakup that could lead to half-metre rise in global sea levels – or more
The only indigenous people left in Europe are struggling to keep their way of life as the Arctic warms up
The loss of its buttressing ice shelf could hasten the demise of the “Doomsday Glacier”
Emerging ice-sheet modeling suggests once initiated, retreat of the Antarctic Ice Sheet (AIS) can continue for centuries. Unfortunately, the short observational record cannot resolve the tipping points, rate of change, and timescale of responses. Iceberg-rafted debris data from Iceberg Alley identify eight retreat phases after the Last Glacial Maximum that each destabilized the AIS within a decade, contributing to global sea-level rise for centuries to a millennium, which subsequently re-stabilized equally rapidly.
We at Sea Research Society's Environmental Affairs Department are very concerned of the melting permafrost terrain and methane clathrate deposits of the Arctic Ocean's sea bed (which are seeding Siberia's air once again with carbon-12). This is because Arctic Ocean's methane clathrates, methane (CH4) & carbon dioxide (CO₂) deposits are thought to be the world's largest reservoir of carbon.