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+--- Thread: Research Earth is getting dimmer + Ancient bogs reveal 15,000-year climate secret (/thread-19214.html)
Earth is getting dimmer + Ancient bogs reveal 15,000-year climate secret - C C - Nov 19, 2025
The Earth is getting dimmer
https://www.sciencenorway.no/antarctica-arctic-climate/the-earth-is-getting-dimmer/2576897
INTRO: NASA satellites show that more sunlight is now being trapped on Earth, absorbed by dark surfaces such as oceans, dense forests, and water vapour. According to a Norwegian climate expert, this could make our planet even warmer than researchers have previously predicted.
The phenomenon, known as the albedo effect, describes Earth's ability to reflect sunlight back into space. Bright surfaces like snow, ice, and clouds reflect sunlight and have a high albedo. Dark surfaces like oceans, asphalt, dense forests, and soil absorb sunlight and have a low albedo.
"When global warming melts snow and ice, we lose those bright, reflective surfaces that send sunlight back into space," Helene Muri, a researcher at NILU and NTNU, tells Science Norway. This creates an accelerating effect that contributes to the Arctic warming faster than the global average.
Gunnar Myhre, research director at CICERO Center for International Climate Research, explains that there used to be a balance between how much sunlight was absorbed and how much was reflected back between the northern and southern hemispheres.
But over the past 20 years, the balance has broken down because the northern hemisphere now absorbs more sunlight than it reflects back into the atmosphere. This is shown in a new study published in the journal Proceedings of the National Academy of Sciences.
Myhre, one of the researchers behind the new study, notes that several factors are driving this change, many linked to pollution and global warming... (MORE - details)
Ancient bogs reveal 15,000-year climate secret, say scientists
https://www.eurekalert.org/news-releases/1106448
INTRO: Scientists have revealed that ancient bogs in the Southern Hemisphere hold clues to a major shift in the Earth's climate thousands of years ago. Researchers looking at peatlands have discovered that sudden shifts in the Southern Westerly Winds 15,000 years ago triggered a massive growth of the swamps.
Geo-experts have never fully understood what caused the bogs to form across the Southern Hemisphere after the last Ice Age. But the scientists behind the new paper, published in Nature Geoscience, now think the shifting winds created the ideal climate for them to grow.
The study was led by the University of Southampton with experts worldwide. Lead author Dr Zoë Thomas, from Southampton, said the findings suggest the winds are not only responsible for regulating carbon stores in peatland, but how much CO2 the ocean absorbs and releases into the atmosphere.
She added: “When the winds shifted north 15,000 years ago, they changed the stirring action in the Southern Ocean which acts as the largest natural carbon sink on earth.”
Peatlands, which are massive natural carbon stores, form when waterlogged soil accumulate layers of dead plant material across thousands of years. The team used peat found across South America, Australasia, southern Africa and the sub-Antarctic islands.
Using radiocarbon-dating, they were able to pinpoint when climatic conditions became wet and favourable enough for sustained plant growth, decay and bog formation.
Dr Thomas added: “We found a clear pattern – major peat growth occurred at the same time the winds shifted north or south, coinciding with changing atmospheric levels of carbon dioxide."
Recent climate observations show the Southern Westerly Winds are shifting again – this time in the opposite direction towards the South Pole due to climate change.
If this trend continues, Dr Thomas warned it could severely disrupt the ocean's ability to capture carbon. She said: “This southerly shift has already led to increases in continental droughts and wildfires across the southern landmasses." (MORE - details, no ads)