Latest news with #EastAntarctic
NDTV
30-05-2025
- Science
- NDTV
Mystery Behind Antarctica Mountain Range Hidden For 500 Million Years Solved
Scientists have solved the mystery behind the mountain range buried under ice in East Antarctica for the last 500 million years. The mysterious and ancient Gamburtsev Subglacial Mountains are similar in shape and scale to the Alps, but not visible due to being trapped beneath kilometres of ice. First discovered by a Soviet expedition using seismic techniques in 1958, the Gamburtsev Mountains are buried beneath the highest point of the East Antarctic ice sheet. While most mountain ranges are eventually worn down by erosion or tectonic events, the Gamburtsev Mountains are preserved by a deep layer of ice, making it one of the best-preserved mountain belts on Earth. Mountains are formed by the collision of two tectonic plates and continue to change over time. The Himalayas are the biggest example after the Indian Plate and Eurasian Plate collided 50 million years ago. This range is rising even today, but Antarctica has been stable all this time, prompting the scientists to look for the secret behind it. According to a study published in the journal Earth and Planetary Science Letters, the mountain range first came into existence 500 million years ago when the Gondwana supercontinent formed from colliding tectonic plates. "The collision triggered the flow of hot, partly molten rock deep beneath the mountains," the authors wrote. "As the mountains continued to take shape, the crust thickened and heated, before becoming unstable and collapsing under their own weight." Other forces led the mountains to partially collapse as well. To further ascertain their hypothesis, the researchers turned to zircon, a mineral that acts like a geological stopwatch. These tiny crystals can survive for billions of years and contain uranium, which decays at a known rate, allowing scientists to determine their age with precision. These grains recorded peak mountain-building around 580 million years ago and the start of structural collapse by 500 million years ago. While gathering rock samples from the mountain remains difficult due to the logistics of drilling through the ice, the model developed by scientists offers new predictions about future exploration.
News18
05-05-2025
- Science
- News18
Ice Gains In East Antarctica Mark Unexpected Reversal After Decades Of Melting
Last Updated: When the ice of the glacier melts, it increases the flow of water in the oceans. If all glaciers and ice sheets melted, the global sea level would rise by more than 195 feet. After melting for several years, Antarctica's ice sheet has shown a dramatic reversal between 2021 and 2023. Marking an unusual turn during these years, Antarctica recorded a net gain of 107.79 gigatons of ice per year. During the time period between 2002 to 2010, Antarctica lost ice at a rate of 73.79 gigatons per year. It increased to 142.06 gigatons annually between 2011 and 2020, according to a study published by Science China Earth Sciences. However, Antarctica gained ice during 2021 and 2023. The gain was noted mainly in four East Antarctic glacier basins — Totten, Moscow, Denman, and Vincennes Bay. Before the reported ice gains, these four areas were losing mass due to faster ice discharge and reduced surface accumulation. What Happens When Ice Of Glaciers Melts? According to NASA, the earth's water is stored in glaciers all around the world and in both the Greenland and Antarctic ice sheets. When the ice melts, it increases the flow of water in the oceans, thus leading to a rise in sea levels. If all glaciers and ice sheets melted, the global sea level would rise by more than 195 feet (60 meters). First Published: May 05, 2025, 11:43 IST
Hindustan Times
05-05-2025
- Science
- Hindustan Times
Good news! Surprising recovery seen in these East Antarctic glaciers after years of melting: What to know
In a surprising turn of events, Antarctica reportedly saw a net gain of 107.79 gigatons of ice per year between 2021 and 2023. This was a rare occurrence, as data from NASA's GRACE and GRACE-FO missions have been telling a grim tale for almost two decades. The data, which have been significant in tracking the Antarctic Ice Sheet's mass changes over the years, showed that from 2002 to 2010, Antarctica lost ice at a rate of 73.79 gigatons per year. The figure then rose to 142.06 gigatons annually between 2011 and 2020, most of the loss coming from West Antarctica and the Wilkes Land-Queen Mary Land (WL-QML) region in East Antarctica, as reported by Business Today. The gain between 2021 and 2023 was especially pronounced in four East Antarctic glacier basins — Totten, Moscow, Denman and Vincennes Bay. Previously, these areas were losing mass due to reduced surface accumulation and faster ice discharge. These glaciers have now begun accumulating ice again. There have been significant implications for sea-level rise. The AIS added that approximately 0.20 mm per year to global sea levels between 2002 and 2010, a number that surged to 0.39 mm per year from 2011 to 2020. However, Antarctica's mass gain helped offset sea-level rise by 0.30 mm per year in 2021-2023. Researchers believe this anomaly can be majorly linked to an increase in snowfall over the continent. However, the four glaciers that recently rebounded are actually among the most unstable glaciers of Antarctica, and hence the gains may just be temporary. In fact, sea levels can rise up by more than 7 meters, should there be a total collapse. Researchers from Tongji University, led by Dr. Wei Wang and Professor Yunzhong Shen, found that accelerated mass loss stems from two main factors – reduced surface mass balance (contributing 72.53% of the intensification) and increased ice discharge into the ocean (responsible for 27.47%). 'This accelerated mass loss was primarily driven by two factors: surface mass reduction (contributing 72.53%) and increased ice discharge (27.47%),' the researchers said, according to
The Guardian
07-03-2025
- Science
- The Guardian
‘A dream experiment': our Australian icebreaker is on a crucial mission to Antarctica
As I write, Australia's national icebreaker, RSV Nuyina, is steaming south-west from Hobart, heading to Antarctica on its first dedicated marine science voyage. Onboard are more than 60 scientists and technicians, many on their first research cruise, gingerly gaining their sea legs as the ship navigates multimetre swells and swirling Southern Ocean lows. After a week or so of travel, they'll push through the sea ice and arrive at their destination for the next 50 days: the remote Denman Glacier ice shelf system in East Antarctica, about 5,000 kilometres south of Australia. As the planet warms, this is a newly emerging region of concern for Antarctica's contribution to sea-level rise, making this mission crucial for Australia's future and the welfare of the global community. The 110-kilometre-long Denman Glacier is a vast river of ice draining the East Antarctic ice sheet. It sits on the seafloor in a canyon about 3.5 kilometres below the surface. As the most northerly ice-shelf system outside the Antarctic peninsula, the Denman Glacier is already one of the fastest retreating glaciers in Australian Antarctic Territory. If the Denman were to melt entirely, it could contribute about 1.5 metres to global sea level rise, let alone what could be unleashed from the inland ice sheet it holds back. This voyage has been a long time coming. It's the culmination of about a decade of planning for a dream experiment to investigate the interactions between ice shelf and ocean, from both the marine and terrestrial sides. Sign up for Guardian Australia's breaking news email But its genesis began even earlier. Intergovernmental Panel on Climate Change (IPCC) reports in 2007 marked a turning point with the recognition that ice sheets are the problem for global sea-level rise, and that ice shelves are their 'soft underbelly'. We realised Antarctica was on the move. In 2008, scientists showed that changes in glacier flow have a 'significant if not dominant impact' on the loss of mass from the Antarctic ice sheet. In 2011, scientists tagged a seal that ended up swimming through a deep trough in the ocean bed near the Denman Glacier, measuring unusually warm water there. In 2019, a new elevation map of the continental bedrock beneath the Antarctic ice sheet revealed the deepest valley on Earth beneath the Denman Glacier. For months from the end of 2020, Australian oceanographers tracked a robotic float that travelled underneath the Denman Glacier ice shelf. Before it disappeared under winter sea ice, the float sent back measurements showing warm water flooding through the deep valley into the ice shelf cavity, enough to rapidly melt the glacier from below. So this voyage aims to discover not only how vulnerable the Denman Glacier is to the warming ocean, but also the likelihood of it making a larger and faster contribution to sea-level rise during the next few decades. The Denman Marine Voyage under the Australian Antarctic Program brings together diverse groups of researchers to answer critical questions about the ocean, ice and climate. The onboard science teams – mostly from universities, with a significant number of early-career scientists and PhD students – will cover a broad range of biological, oceanographic, geological and atmospheric research. As an oceanographer, perhaps what I'm most excited about is the prospect to be measuring the properties of seawater – from both underneath the glacier and over the continental shelf – all at the same time, in a region where few observations have been collected before. In January, as part of the Denman Terrestrial Campaign from the land side, a string of moored sensors was lowered through a hole in the floating ice shelf and left hanging in a deep underwater canyon near the grounding line of a glacier. Every day the mooring automatically sends researchers the temperature, salinity and current speed of the water. These data help us track the pathways for deep, warm, salty water to access ice shelves, where it can drive rapid melting. And now, with the RSV Nuyina moving into position to take simultaneous measurements right in front of the glacier, we should have the vital link that connects the warm flows we detect just offshore in the ocean to what's under the ice shelves. The only way to get information like this is to be there. With it, we can refine our projections and better understand the hazard that Antarctica presents to our coastlines from the global sea-level rise we can expect – or avoid – this century. Prof Nathan Bindoff leads the Australian Antarctic Program Partnership, based in the Institute for Marine and Antarctic Studies at the University of Tasmania
