Veille 2.1

OA - Liste OA - Liste

Sélection du moment:


Langue(3/3)
Médias(8/8)
Résultats pour:
arctic

mars 2024

De hele mensheid profiteert van Antarctica en de oceaan die het continent omringt, schrijven Natalie Stoeckl en Rachel Baird, hoogleraren aan de Universiteit van Tasmanië. Een schatting van de economische waarde kan volgens hen een goede motivatie zijn voor de bescherming van dit unieke ecosysteem.

février 2024

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.

novembre 2023

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'.

octobre 2023

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

août 2023

Antarctica’s sea ice levels are plummeting as extreme weather events happen faster than scientists predicted

juillet 2023

Le président russe Vladimir Poutine a donné jeudi à Mourmansk le coup d'envoi de la première chaîne d'Arctic LNG 2, gigantesque projet de gaz naturel liquéfié (GNL) dans l'Arctique, dont le français TotalEnergies s'est retiré en 2022.
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.
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
The world just had the hottest June on record, with unprecedented sea surface temperatures and record low Antarctic sea ice extent, according to a new report.

juin 2023

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
Ice-free summers inevitable even with sharp emissions cuts and likely to result in more extreme heatwaves and floods

avril 2023

De ijskappen op Groenland en Antarctica smolten nooit zo snel dan de voorbije tien jaar. De slechtste zeven jaar sinds het begin van de metingen hebben zich in het afgelopen decennium voorgedaan. Wetenschappers wijzen de klimaatverandering aan als schuldige.
Seafloor landforms reveal that ice sheets can collapse at 600 metres per day.
De diepzeestromingen rond het Antarctische continent tonen tekenen van vertraging, stelt onderzoek in Nature. Een totale ineenstorting zou wereldwijde gevolgen hebben voor de oceanen en het klimaat.