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Glacial earthquakes are a special type of earthquake generated in cold, icy regions. First discovered in the northern hemisphere more than 20 years ago, these quakes occur when huge chunks of ice fall from glaciers into the sea. Until now, only a very few have been found in the Antarctic. In a new study soon to be published in Geophysical Research Letters, I present evidence for hundreds of these quakes in Antarctica between 2010 and 2023, mostly at the ocean end of the Thwaites Glacier – the so-called Doomsday Glacier that could send sea levels rising rapidly if it were to collapse.
Researchers have discovered dozens of new methane seeps littering the ocean floor in the Ross Sea coastal region of Antarctica, raising concerns of an unknown positive climate feedback loop that could accelerate global warming.
We report striking discoveries of numerous seafloor seeps of climate-reactive fluid and gases in the coastal Ross Sea, indicating this process may be a common phenomenon in the region. We establish the recent emergence of many of these seep features, based on their discovery in areas routinely surveyed for decades with no previous seep presence. Additionally, we highlight impacts to the local benthic ecosystem correlated to seep presence and discuss potential broader implications. With these discoveries, our understanding of Antarctic seafloor seeps shifts from them being rare phenomenon to seemingly widespread, and an important question is raised about the driver of seep emergence in the region. While the origin and underlying mechanisms of these emerging seep systems remains unknown, similar processes in the paleo-record and the Arctic have been attributed to climate-driven cryospheric change. Such a mechanism may be widespread around the Antarctic Continent, with concerning positive feedbacks that are curr
The 511 billion barrels reported is nearly double Saudi Arabia’s proven reserves and more than ten times the North Sea’s output over the last 50 years.
New research catalogs several “abrupt changes,” like a precipitous loss of sea ice, unfolding in Antarctica with dire implications for us all.
The vast ice of Antarctica has long seemed impregnable. But sudden changes are arriving – from shrinking sea ice to melting ice sheets and slowing ocean currents.
Het zeewater rond Antarctica werd het afgelopen decennium steeds zouter, blijkt uit een nieuwe studie. Hoe dat kan, kunnen de onderzoekers nog niet verklaren. Wat betekent dit voor het klimaatprobleem?
For decades, the surface of the polar Southern Ocean (south of 50°S) has been freshening—an expected response to a warming climate. This freshening enhanced upper-ocean stratification, reducing the upward transport of subsurface heat and possibly contributing to sea ice expansion. It also limited the formation of open-ocean polynyas. Using satellite observations, we reveal a marked increase in surface salinity across the circumpolar Southern Ocean since 2015. This shift has weakened upper-ocean stratification, coinciding with a dramatic decline in Antarctic sea ice coverage. Additionally, rising salinity facilitated the reemergence of the Maud Rise polynya in the Weddell Sea, a phenomenon last observed in the mid-1970s.
Despite working on polar science for the British Antarctic Survey for 20 years, Louise Sime finds the magnitude of potential sea-level rise hard to comprehend
Le ministre de l’intérieur américain a notamment annoncé le rétablissement d’un programme permettant d’exploiter le pétrole et le gaz dans l’ensemble de l’Arctic National Wildlife Refuge, une aire protégée qui s’étend sur plus de 630 000 hectares.
Antarctica's remote and mysterious current has a profound influence on the climate, food systems and Antarctic ecosystems. Can we stop it weakening by 2050?
The Antarctic Circumpolar Current (ACC) is the world's strongest ocean current and plays a disproportionate role in the climate system due to its role as a conduit for major ocean basins. This current system is linked to the ocean's vertical overturning circulation, and is thus pivotal to the uptake of heat and CO2 in the ocean. The strength of the ACC has varied substantially across warm and cold climates in Earth's past, but the exact dynamical drivers of this change remain elusive. This is in part because ocean models have historically been unable to adequately resolve the small-scale processes that control current strength. Here, we assess a global ocean model simulation which resolves such processes to diagnose the impact of changing thermal, haline and wind conditions on the strength of the ACC. Our results show that, by 2050, the strength of the ACC declines by ∼20% for a high-emissions scenario. This decline is driven by meltwater from ice shelves around Antarctica, which is exported to lower latit
Mechanisms behind a steep rise in temperature
Sea ice extent for the Arctic overall as of mid-December is at the lowest for this point in the season in the entire satellite era record (since autumn 1978) Whether this is a transient low extent or not, expanded open water now, with the winter solstice upon us, means that there’s less time for ice, once it forms, to thicken up before the spring melt commences in a few months.
In March 2022, a New York City-sized ice shelf collapsed in East Antarctica, long thought to be relatively stable against rapid change. The Conger-Glenzer ice shelf collapsed following decades of ocean-induced thinning, allowing its long-stabilizing features to transform into destabilizing ones.
Global warming has already caused the Arctic to release more climate-warming methane—but exactly how much will depend closely on the actions we take to halt climate change.
The Atlantic Meridional Overturning Circulation is the main driver of northward heat transport in the Atlantic Ocean today, setting global climate patterns. Whether global warming has affected the strength of this overturning circulation over the past century is still debated: observational studies suggest that there has been persistent weakening since the mid-twentieth century, whereas climate models systematically simulate a stable circulation. Here, using Earth system and eddy-permitting coupled ocean–sea-ice models, we show that a freshening of the subarctic Atlantic Ocean and weakening of the overturning circulation increase the temperature and salinity of the South Atlantic on a decadal timescale through the propagation of Kelvin and Rossby waves. We also show that accounting for upper-end meltwater input in historical simulations significantly improves the data–model agreement on past changes in the Atlantic Meridional Overturning Circulation, yielding a slowdown of 0.46 sverdrups per decade since 1950
Harry is a U.K.-based senior staff writer at Live Science. He studied marine biology at the University of Exeter before training to become a journalist. He covers a wide range of topics including space exploration, planetary science, space weather, climate change, animal behavior, evolution and paleontology. His feature on the upcoming solar maximum was shortlisted in the "top scoop" category at the National Council for the Training of Journalists (NCTJ) Awards for Excellence in 2023.
A new declaration aims to make the southernmost continent an autonomous legal entity, akin to a nation-state, with inherent rights to participate in decision making that affects it.
De oppervlakte van het Antarctisch Schiereiland waar planten groeien, is vandaag minstens 12 keer groter dan in 1986. Dat blijkt uit satellietfoto's. De vergroening van de Zuidpool, door de klimaatverandering, gaat steeds sneller. Daardoor zou Antarctica er binnen enkele decennia wel eens heel anders kunnen uitzien.
As a six-year investigation into the Thwaites glacier in Antarctica wraps up, the scientists involved are pessimistic for the future of this glacier and the consequences for sea level rise
Arctic Sea ice reaches it's minimum extent each year around the middle of September. This year is one of the lowest in recorded history. Ocean temperatures have been so 'off the charts' in 2023 and 2024 that scientists fear those waters have reached their capacity to mop up after us humans and are now starting to release that energy. On our current trajectory, by 2100, our planet will reach a temperature not seen for 3 MILLION years!. So...what's the plan???
Het gat in de ozonlaag is zich pas begin deze maand beginnen vormen, later dan normaal. Dat meldt de Europese aardobservatiedienst Copernicus. Het gat is daardoor ook kleiner dan de voorgaande jaren. Dat heeft vooral te maken met de temperatuur van de stratosfeer boven Antarctica, die deze zomer bokkensprongen maakte.
The Svalbard archipelago’s ice caps suffered extreme episodes of melting in summer 2024, brought on by exceptionally high air temperatures.
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.
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.
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
Antarctica’s sea ice levels are plummeting as extreme weather events happen faster than scientists predicted
