- Muslim women break taboos navigating east London's waterways
- Nepal dam-building spree powers electric vehicle boom
- More than 60 dead from storm Helene as rescue, cleanup efforts grow
- Dozens missing, 9 dead in migrant boat wreck off Spanish Canaries
- Death toll from Hurricane John hits eight in Mexico
- Storm Helene's toll rises as rescue and cleanup efforts gain pace
- SpaceX launches mission to return stranded astronauts
- Storm Helene kills 44, threatens more 'catastrophic' flooding as cleanup begins
- SpaceX set to launch mission to return stranded astronauts
- Storm Helene kills 44, threatens more 'catastrophic' flooding
- Boeing strike grinds on as latest talks fail to reach agreement
- Iran 'news' sites, hackers target Trump ahead of US election
- US ports brace for potential dockworkers strike
- Japan's speedy, spotless Shinkansen bullet trains turn 60
- US hurricane deaths rise to 44, fears of more 'catastrophic' flooding
- Global stocks mostly rise, cheering Beijing stimulus
- Europe en route for Moon with new simulator, says astronaut Pesquet
- Fireworks forecast if comet survives risky Sun flypast
- Argentina judge orders dictionary to delete pejorative definition of 'Jewish'
- Global stocks rise on rate hopes, Beijing stimulus
- S.African woman turns 118, among the oldest in the world
- UK clears $4 bn AI partnership between Amazon, Anthropic
- Barca fans barred from Champions League away game over racist banner
- Chinese stocks extend surge, Europe higher on Beijing stimulus
- Pope says Church must 'seek forgiveness' for child sexual abuse
- China caps week of 'bazooka' stimulus for ailing economy with rate cut
- Cuts, cash, credit: China bids to jumpstart flagging economy
- France's debt weighs heavier ahead of budget debate
- Iran treads carefully, backing Hezbollah while avoiding war
- Return to sender: waste stranded at sea stirs toxic dispute
- 'Broken' news industry faces uncertain future
- On remote Greek island, migratory birds offer climate clues
- Taken from mother by nuns, victim seeks answers as pope visits Belgium
- China cuts amount banks hold in reserve to boost lending
- Hong Kong, Shanghai extend surge as China optimism boosts markets
- Vietnam president reiterates support for Cuba during official visit
- Drought reduces Amazon River in Colombia by as much as 90%: report
- Stay or go? Pacific Islanders face climate's grim choice
- Florida bracing for 'unsurvivable' Hurricane Helene
- Poverty rises to over 52 percent in Milei's Argentina
- Chloe's see-through look may not be for Kamala Harris
- Champagne houses abuzz over English sparkling wine
- Macron, Trudeau pledge to work for 'decarbonized' economies
- Hurricanes, storms, typhoons... Is September wetter than usual?
- China stimulus, tech optimism boost stock markets
- 'Unsurvivable' Hurricane Helene races towards Florida
- Macron meets Trudeau in Canada as both face political setbacks
- South Korea surges in UN innovation index
- Chloe's see-through look may not be for Kamala
- Floods threaten Niger's historic 'gateway to the desert'
Half of world's glaciers expected to vanish by 2100: study
Half of the Earth's glaciers, notably smaller ones, are destined to disappear by the end of the century because of climate change, but limiting global warming could save others, according to a new study.
The findings, published in the journal Science on Thursday, provide the most comprehensive look so far at the future of the world's 215,000 glaciers.
The authors emphasized the importance of restricting greenhouse gas emissions to limit the consequences from glacier melt such as sea level rise and depletion of water resources.
To help orient policy makers, the study looked at the impact of four scenarios on glaciers, where global mean temperature change is 1.5 degrees Celsius (2.7 degrees Fahrenheit), 2.0C, 3.0C and 4.0C.
"Every degree increase produces more melt and loss," said Regine Hock of the University of Oslo and University of Alaska Fairbanks, a co-author of the study.
"But that also means if you reduce the temperature increase, you can also reduce that mass loss," Hock told AFP. "So in that sense, there is also a little bit of hope."
Even if global temperature rise is limited to 1.5C above pre-industrial levels -- the most ambitious goal of the Paris Agreement -- the researchers estimated that 49 percent of the world's glaciers would vanish by the year 2100.
That would represent about 26 percent of the world's glacier mass because the smallest glaciers would be those first impacted.
Global mean temperature is currently estimated to be increasing by 2.7C which would result in a near-complete loss of glaciers in Central Europe, Western Canada and the continental United States and New Zealand.
"Regions with relatively little ice like the European Alps, the Caucasus, the Andes, or the western US, they lose almost all the ice by the end of the century almost no matter what the emission scenario is," Hock said. "So those glaciers, they're more or less doomed."
- 'Up to the policy makers' -
Under the worst-case scenario -- global temperature rise of 4.0C -- giant glaciers such as those in Alaska would be more affected and 83 percent of glaciers would disappear by the end of the century.
Glacier loss would also exacerbate sea level rise.
"The glaciers that we are studying are only one percent of all ice on Earth," said Hock, "much less than the Greenland ice sheet and the Antarctic ice sheet.
"But they have contributed to sea level rise almost just as much as the Greenland and Antarctic ice sheet together in the last three decades," she said.
Warming of 1.5C would lead to an increase in average sea levels of nine centimeters while temperatures 4.0C higher would cause 15 centimeters of sea level rise.
"It doesn't sound very much, nine centimeters up to 15 centimeters," Hock said, "but it's not global sea level that is that much of a concern.
"It's mostly associated storm surges," she said, which have the potential to cause "a lot more damage."
The disappearance of glaciers will also have an impact on water resources because they provide freshwater for some two billion people.
"The glaciers compensate for the loss of water in summer when it's not raining much and it's hot," Hock said.
The study's projections, which are more pessimistic than those of UN climate experts, were reached through observations of the mass of each glacier through the decades and computer simulations.
Despite the alarming findings, Hock said "it is possible to reduce the mass loss by human action.
"If it happens is of course a different question," she said. "If that happens is of course up to the policy makers."
Ch.Lefebvre--CPN