Antarctica’s hidden threat: meltwater under the ice sheet amplifies sea-level rise

LouieLea, Shutterstock Chen Zhao, University of Tasmania and Ben Galton-Fenzi, Australian Antarctic DivisionOne of the biggest challenges in predicting Antarctica’s deeply uncertain future is understanding exactly what’s driving its ice loss. A vast network of lakes and streams lies beneath the thick ice sheet. This water can lubricate the ice, allowing it to slide more rapidly toward the ocean. Our new research shows “subglacial water” plays a far larger role in Antarctic ice loss than previously thought. If it’s not properly accounted for, future sea-level rise may be vastly underestimated. Including the effects of evolving subglacial water in ice sheet models can triple the amount of ice flowing to the ocean. This adds more than two metres to global sea levels by 2300, with potentially enormous consequences for coastal communities worldwide. How hidden lakes threaten Antarctic Ice Sheet stability. (European Space Agency) Understanding the role of subglacial water Subglacial water forms when the base of the ice sheet melts. This occurs either due to friction from the movement of the ice, or geothermal heat from the bedrock below. The presence of subglacial water enables ice to slide over the bedrock more easily. It can also cause further melting under ice shelves, leading to...

Read More........→April 13, 2025

Number of Monarch Butterflies Wintering in Mexico is Way Up–Doubling the Forest Acreage Over Last Year

Monarch butterflies in Michoacán, Mexico forest by Alex GuillaumeThe number of monarch butterflies overwintering this year in Mexico has nearly doubled, according to the annual census released last week by the World Wildlife Fund in Mexico and their partners.During the last few months in 2025, the population of eastern monarchs occupied 4.42 acres of central Mexico’s forests—up from 2.22 acres during the previous winter.The encouraging survey was conducted with help from Mexico’s National Commission of Protected Natural Areas and local communities, and it serves as an important indicator of the health of a monarch population that has been clawing its way back from dangerously low levels this century.“It’s now time to turn this year’s increase into a lasting trend with an all-hands approach where governments, landowners, conservationists, and citizens continue to safeguard critical habitats along the monarch’s North American migratory route,” said Jorge Rickards, director general of WWF Mexico, who recognized the key role of local communities and the government of Mexico in conserving the forest that provides an annual respite to this iconic species.Scientists attribute much of this year’s population growth to better weather conditions in 2024—with less severe drought than in previous years along their migration route from the U.S....

Read More........→April 11, 2025

Southern elephant seals are adaptable – but they struggle when faced with both rapid climate change and human impacts

Wikimedia Commons/Antoine Lamielle, CC BY-SA Nic Rawlence, University of Otago; Mark de Bruyn, Griffith University, and Michael Knapp, University of OtagoSouthern elephant seals (Mirounga leonina) are an iconic species of the Southern Ocean. But with rapid environmental changes in their ocean home, the seals’ population range has been shifting. Once spread across vast areas of the southern hemisphere, these apex predators are facing challenges from both climate shifts and human activities. Our new research examines ancient and modern DNA, archaeological records and ecological data. It reveals how these large marine mammals have adapted – and sometimes failed to adapt – to such pressures since the height of the last Ice Age thousands of years ago. A dynamic evolutionary history Today, the largest southern elephant seal populations are found on subantarctic islands, including South Georgia, Macquarie Island and the Falkland Islands. These colonies act as global strongholds for the species. Yet in the past, until just a few hundred years ago, many smaller populations existed on the Victoria Land Coast in Antarctica and closer to temperate zones, on mainland Australia and New Zealand. Our study focused on the Australasian lineage of southern elephant seals, drawing on samples from these ancient colonies. By analysing...

Read More........→March 31, 2025

Why can’t I sleep? 4 ways climate change could be keeping you up at night and what you can do about it

Marcos Mesa Sam Wordley/Shutterstock Ty Ferguson, University of South Australia and Carol Maher, University of South AustraliaTossing and turning on sweltering summer nights? You’re not alone. As temperatures rise due to climate change, our sleep is becoming shorter and more disrupted. But it’s not just the heat keeping us awake – climate change creates multiple challenges to our nightly slumber, which may be affecting our health. What happens when we don’t get enough sleep? Sleep isn’t just rest – it’s vital for our health. Adults need at least seven hours per night to maintain cognitive function, memory and emotional balance. Poor sleep immediately impacts mood and attention, while chronic sleep issues increase risk of diabetes, obesity, depression, heart disease and even premature death. So, how is climate change impacting our sleep? 1. Overnight temperatures are rising Our circadian rhythm – that internal biological clock – requires our internal body temperature to drop at night for quality sleep. The ideal room temperature for sleep is 15°C to 19°C. Rising outdoor temperatures make this body temperature increasingly difficult to maintain, especially for those without air conditioning. Paradoxically, widespread air conditioning use further contributes to climate change by using fossil-energy, which creates...

Read More........→March 21, 2025

Countries Are Breathing the Cleanest Air in Centuries and Offer Lessons to the Rest of Us

An article at Our World in Data recently explored trends in air quality across a selection of high and middle-income countries, and found that not only is the West breathing better air than at perhaps any point since urbanization, but that developing nations likely won’t need 100 years or more to arrive at similar outcomes.Published by Hannah Ritchie, the article focuses on two kinds of gases emitted from industrial activity: sulfur dioxide (SO2) and nitrogen oxide (NOx). Both enter the air we breathe from the burning of fossil fuels—coal in particular—while the latter is emitted mostly from internal combustion engines.Bad air quality is responsible for millions of lost life years worldwide from respiratory problems, cardiovascular issues, and neurological disease—all of which can develop and become exasperated under prolonged exposure to air pollutants.UK sulphur dioxide emissions – credit Community Emissions Data System (CEDS) 2024, CC BY license.As seen in this chart, emissions of SO2 have just dipped under levels seen at the earliest periods of British industrialization. Before this, city and town air quality would have been badly tainted through emissions of wood smoke, so it’s safe to assume that 2022 marked the best British air in many centuries, not just the last two.SO2 enters the ambient air primarily in urban environments...

Read More........→March 06, 2025

More Than 50,000 Pounds of Trash Removed from the Arctic in 2023

credit – Protection of the Arctic Marine EnvironmentOver 50,000 pounds of trash have been removed from the Arctic in 2023 after a multilateral effort flooded critical northern ecosystems with volunteers.Working during the brief Arctic summer, clean-up operations were carried out in Alaska, Greenland, Norway, and Iceland.Nearly 2,000 volunteers were enlisted across the treaty nations of the Arctic Council, an inter-governmental panel on peaceful and sustainable use and protection of the Arctic zone formed by the nations that pierce its frozen borders, and the indigenous peoples that call it home.The council is divided into working groups that address certain issues, and the Protection of the Arctic Marine Environment (PAME), founded in 1991, partnered with the Ocean Conservancy and various local groups like Keep Norway Clean to organize this sizable operation through its Arctic Cleanup initiative.These annual clean-ups have removed over 100,000 pounds of trash between 2021 and 2023. The overwhelming majority of trash originates in the fishing industry, Keep Norway Clean reports.Arctic cleanup is both challenging and costly, the government-funded nonprofit writes. Long distances, difficult-to-access areas, scattered populations, short cleanup seasons, and limited access to waste management, are the main challenges for voluntary cleanup...

Read More........→February 25, 2025

It’s official: Australia’s ocean surface was the hottest on record in 2024

Moninya Roughan, UNSW SydneyAustralia’s sea surface temperatures were the warmest on record last year, according to a snapshot of the nation’s climate which underscores the perilous state of the world’s oceans. The Bureau of Meteorology on Thursday released its annual climate statement for 2024 – the official record of temperature, rainfall, water resources, oceans, atmosphere and notable weather. Among its many alarming findings were that sea surface temperatures were hotter than ever around the continent last year: a whopping 0.89°C above average. Oceans cover more than 70% of Earth’s surface, and their warming is gravely concerning. It causes sea levels to rise, coral to bleach and Earth’s ice sheets to melt faster. Hotter oceans also makes weather on land more extreme and damages the marine life which underpins vital ocean ecosystems. What the snapshot showed Australia’s climate varies from year to year. That’s due to natural phenomena such as the El Niño and La Niña climate drivers, as well as human-induced climate change. The bureau confirmed 2024 was Australia’s second-warmest year since national records began in 1910. The national annual average temperature was 1.46°C warmer than the long-term average (1961–90). Heatwaves struck large parts of Australia early in the year, and...

Read More........→February 13, 2025

What’s the difference between climate and weather models? It all comes down to chaos

Nadia Piet/AIxDESIGN & Archival Images of AI / Better Images of AI , CC BY-SA Andy Hogg, Australian National University; Aidan Heerdegen, Australian National University, and Kelsey Druken, Australian National UniversityWeather forecasts help you decide whether to go for a picnic, hang out your washing or ride your bike to work. They also provide warnings for extreme events, and predictions to optimise our power grid. To achieve this, services such as the Australian Bureau of Meteorology use complex mathematical representations of Earth and its atmosphere – weather and climate models. The same software is also used by scientists to predict our future climate in the coming decades or even centuries. These predictions allow us to plan for, or avoid, the impacts of future climate change. Weather and climate models are highly complex. The Australian Community Climate and Earth System Simulator, for example, is comprised of millions of lines of computer code. Without climate and weather models we would be flying blind, both for short-term weather events and for our long-term future. But how do they work – and how are they different? The same physical principles Weather is the short-term behaviour of the atmosphere – the temperature on a given day, the wind, whether it’s raining and how much. Climate is about long-term...

Read More........→February 11, 2025

Scientists Drill Ice Core–2 Miles Down–Extracting 1.2 Million Years of Climate Record On Earth

Antarctica ice core – PNRA / IPEV via SWNSAn international team of scientists in the Antarctic has successfully extracted what is believed to be the world’s oldest ice—a historic milestone for climate science.They drilled down almost two miles to extract 2.8-km of ice core, reaching the actual bedrock beneath the Antarctic ice sheet.The air bubbles trapped inside the ice are “like tiny time capsules of Earth’s atmospheric past”. The samples equate to a continuous record of climate history dating back to 1.2 million years ago, which could illuminate the mysteries of glacial climate cycles.This was the fourth Antarctic field mission for the Europeans behind the ‘Beyond EPICA – Oldest Ice’ project, funded by the European Commission.They achieved more than 200 days of successful drilling and ice core processing operations across four seasons in the harsh environment of the central Antarctic plateau, working at an altitude of 3,200 meters above sea level with an average summer temperature of -35°C.The ice core from Beyond EPICA will offer unprecedented insights into the Mid-Pleistocene Transition, a remarkable period between 900,000 and 1.2 million years ago when glacial cycles slowed down from 41,000-years to 100,000-year intervals.The reasons behind this shift remain one of climate science’s enduring mysteries, one which this project...

Read More........→February 07, 2025

First major chunk breaks off world's biggest iceberg

PARIS - An enormous chunk has broken off the world's largest iceberg, in a possible first sign the behemoth from Antarctica could be crumbling.The colossal iceberg -- which is more than twice the size of Greater London and weighs nearly one trillion tonnes -- had largely stayed intact since it started slowly moving north in 2020.It has been drifting toward the remote island of South Georgia in the South Atlantic, raising the prospect it could run aground in shallower water and disrupt feeding for baby penguins and seals.But a chunk about 19 kilometres (12 miles) long has cleaved off, said Andrew Meijers from the British Antarctic Survey, who encountered the iceberg in late 2023 and has tracked its fate via satellite ever since."This is definitely the first significant clear slice of the iceberg that's appeared," the physical oceanographer told AFP.Soledad Tiranti, a glaciologist currently on an Argentinian exploration voyage in the Antarctic, also told AFP that a section had "broken" away.The jagged piece has an area of roughly 80 square kilometres (31 square miles) -- huge in its own right, but just a fraction of the approximately 3360 square kilometres that remained.Meijers said icebergs were full of deep fractures, and although this monumental specimen had shrunk over time and lost a much smaller piece, it had "held together...

Read More........→February 06, 2025

How is Antarctica melting, exactly? Crucial details are beginning to come into focus

The front of the Ross Ice Shelf floats in the Ross Sea, Antarctica. Matt Siegfried/Scripps Institution of Oceanography, CC BY-NC Madelaine Gamble Rosevear, University of Tasmania; Ben Galton-Fenzi; Bishakhdatta Gayen, The University of Melbourne, and Catherine Vreugdenhil, The University of MelbourneThe size of the Antarctic ice sheet can be hard to comprehend. Two kilometres thick on average and covering nearly twice the area of Australia, the ice sheet holds enough freshwater to raise global sea levels by 58 metres. Ice loss from this sheet is projected to be the leading driver of sea level rise by 2100, yet its contribution remains highly uncertain. While sea levels are certain to rise this century, projections of the contribution from Antarctic ice vary from a 44 cm rise to a 22 cm fall. Much of this uncertainty is because the ocean processes that control the fate of the sheet occur on an incredibly small scale and are very difficult to measure and model. But recently scientists have made significant progress in understanding this “ice-ocean boundary layer”. This progress is the subject of our new review paper, published today in Annual Reviews. Shrinking, thinning and retreating At the margins of the Antarctic ice sheet, glaciers flow into the Southern Ocean, forming floating ice shelves. These ice shelves act as...

Read More........→January 22, 2025

In 2025, let’s make it game on – not game over – for our precious natural world

Jakub Maculewicz/Shutterstock Darcy Watchorn, Deakin University and Marissa Parrott, The University of MelbourneIt’s just past midnight in the cool, ancient forests of Tasmania. We’ve spent a long day and night surveying endangered Tasmanian devils. All around, small animals scurry through bushes. A devil calls in the darkness. Microbats swoop and swirl as a spotted-tailed quoll slips through the shadows. Working here is spine-tingling and electric. Weeks later, we’re in a moonlit forest in Victoria. It was logged a few years earlier and burnt by bushfire a few decades before that. The old trees are gone. So too are the quolls, bats and moths that once dwelled in their hollows. Invasive blackberry chokes what remains. The silence is deafening, and devastating. In our work as field biologists, we often desperately wish we saw a place before it was cleared, logged, burnt or overtaken by invasive species. Other times, we hold back tears as we read about the latest environmental catastrophe, overwhelmed by anger and frustration. Perhaps you know this feeling of grief? The new year is a chance to reflect on the past and consider future possibilities. Perhaps we’ll sign up to the gym, spend more time with family, or – perish the thought – finally get to the dentist. But let us also set a New Year’s resolution for nature. Let’s...

Read More........→January 17, 2025