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In a new study, a team of geologists and biologists led by CU Boulder resurrected ancient microbes that had been trapped in ice—in some cases for around 40,000 years.

A first thought when describing a rock formation likely isn't a mille-feuille, but there are actually certain types composed of many thin layers that bring the flaky pastry to mind. Not only that—but these rocks can quite literally fold under pressure. These formations have the interesting ability to fold under compressive forces and form sharply localized bends known as kink bands.

A research group in Japan has suggested that ash released from volcanic eruptions on Nishinoshima Island—part of Japan's Ogasawara Islands—led to a temporary surge in phytoplankton levels in the seawater around Mukojima Island, which is located 130 km northeast of Nishinoshima and is also part of the Ogasawara Islands.

The towering trees of old forests store massive amounts of carbon in their trunks, branches, and leaves. When these ancient giants are replaced by a younger cohort after logging, wildfire, or other disturbances, much of this carbon stock is lost.

“We wanted to actually quantify what it means if an old forest becomes young.”

“We’ve known for a long time that forest age is a key component of the carbon cycle,” said Simon Besnard, a remote sensing expert at the GFZ Helmholtz Centre for Geosciences in Potsdam, Germany. “We wanted to actually quantify what it means if an old forest becomes young.”

The resulting study, published in Nature Ecology and Evolution, measured the regional net aging of forests around the world across all age classes between 2010 and 2020, as well as the impact of these changes on aboveground carbon.

To do this, the team developed a new high-resolution global forest age dataset based on more than 40,000 forest inventory plots, biomass and height measurements, remote sensing observations, and climate data. They combined this information with biomass data from the European Space Agency and atmospheric carbon dioxide observations.

The results point to large regional differences. While forests in Europe, North America, and China have aged during this time, those in the Amazon, Southeast Asia, and the Congo Basin were younger in 2020 than 10 years prior.

A number of recent studies have shown that forests are getting younger, but the new analysis quantifies the impact of this shift on a global level, said Robin Chazdon, a tropical forest ecologist at the University of the Sunshine Coast in Queensland, Australia, who was not involved in the study. “That’s noteworthy and a very important concept to grasp because this has global implications, and it points out where in the world these trends are strongest.”

Carbon Impact

The study identifies the tropics, home to some of the world’s oldest forests, as a key region where younger forests are replacing older ones.

In this image from 2020, old-growth forests are most evident in tropical areas in South America, Africa, and Southeast Asia. Credit: Besnard et al., 2021, https://doi.org/10.5194/essd-13-4881-2021, CC BY 4.0

On average, forests that are at least 200 years old store 77.8 tons of carbon per hectare, compared to 23.8 tons per hectare in the case of forests younger than 20 years old.

The implications for carbon sequestration are more nuanced, however. Fast-growing young forests, for instance, can absorb carbon much more quickly than old ones, especially in the tropics, where the difference is 20-fold. But even this rate of sequestration is not enough to replace the old forests’ carbon stock.

Ultimately, said Besnard, “when it comes to a forest as a carbon sink, the stock is more important than the sink factor.”

“It’s usually more cost-, carbon-, and biodiversity-effective to keep the forest standing than it is to try to regrow it after the fact.”

In the study, only 1% of the total forest area transitioned from old to young, primarily in tropical regions. This tiny percentage, however, accounted for more than a third of the lost aboveground carbon documented in the research— approximately 140 million out of the total 380 million tons.

“It’s usually more cost-, carbon-, and biodiversity-effective to keep the forest standing than it is to try to regrow it after the fact. I think this paper shows that well,” said Susan Cook-Patton, a reforestation scientist at the Nature Conservancy in Arlington, Va., who was not involved in the study. “But we do need to draw additional carbon from the atmosphere, and putting trees back in the landscape represents one of the most cost-effective carbon removal solutions we have.”

The increased resolution and details provided by the study can help experts better understand how to manage forests effectively as climate solutions, she said. “But forest-based solutions are not a substitute for fossil fuel emissions reductions.”

Open Questions

When carbon stored in trees is released into the atmosphere depends on what happens after the trees are removed from the forest. The carbon can be stored in wooden products for a long time or released gradually through decomposition. Burning, whether in a forest fire, through slash-and-burn farming, or as fuel, releases the carbon almost instantly.

“I think there is a research gap here: What is the fate of the biomass being removed?” asked Besnard, pointing out that these effects have not yet been quantified on a global scale.

Differentiating between natural, managed, and planted forests, which this study lumps together, would also offer more clarity, said Chazdon: “That all forests are being put in this basket makes it a little bit more challenging to understand the consequences not only for carbon but for biodiversity.”

She would also like to see future research on forest age transitions focus on issues beyond carbon: “Biodiversity issues are really paramount, and it’s not as easy to numerically display the consequences of that as it is for carbon.”

“We are only looking at one metric, which is carbon, but a forest is more than that. It’s biodiversity, it’s water, it’s community, it’s many things,” agreed Besnard.

—Kaja Šeruga, Science Writer

Citation: Šeruga, K. (2025), Old forests in the tropics are getting younger and losing carbon, Eos, 106, https://doi.org/10.1029/2025EO250369. Published on 2 October 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Source: AGU Advances

This is an authorized translation of an Eos article. 本文是Eos文章的授权翻译。

近年来，科学家们发现，基于机器学习的天气模型可以比传统模型更快地做出天气预测，且使用更少的能耗。然而，许多这些模型无法准确预测未来15天以上的天气，并且到第 60 天时就会开始模拟出不切实际的天气。

深度学习地球系统模型（Deep Learning Earth System Model，简称DLESyM）建立在两个并行运行的神经网络上：一个模拟海洋，另一个模拟大气。在模式运行期间，对海洋状况的预测每四个模式日更新一次。由于大气条件演变得更快，对大气的预测每12个模式小时更新一次。

该模型的创建者Cresswell-Clay 等人发现，DLESyM 与过去观测到的气候非常吻合，并能做出准确的短期预测。以地球当前的气候为基准，它还可以在不到 12 小时的计算时间内，准确模拟 1000 年周期内的气候和年际变化。它的性能通常与基于耦合模式比对计划第六阶段（CMIP6）的模型相当，甚至优于后者，CMIP6目前在计算气候研究中被广泛使用。

DLESyM 模型在模拟热带气旋和印度夏季季风方面优于 CMIP6 模型。它至少与 CMIP6 模型一样准确地捕捉了北半球大气“阻塞”事件的频率和空间分布，而这些事件可能导致极端天气。此外，该模型预测的风暴也非常真实。例如，在 1000 年模拟结束时（3016 年）生成的东北风暴的结构与 2018 年观测到的东北风暴非常相似。

然而，新模型和CMIP6 模型都无法很好地描述大西洋飓风 的气候特征。此外，对于中期预报（即未来 15 天左右的预报），DLESyM 的准确性低于其他机器学习模型。尤其重要的是，DLESyM 模型仅对当前气候进行模拟，这意味着它没有考虑人类活动引起的气候变化。

作者认为，DLESyM模型的主要优势在于，它比运行CMIP6 模型所需的计算成本要低得多，这使得它比传统模型更容易使用。(AGU Advances, https://doi.org/10.1029/2025AV001706, 2025)

—科学撰稿人Madeline Reinsel

This translation was made by Wiley. 本文翻译由Wiley提供。

Read this article on WeChat. 在微信上阅读本文。

Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

For as long as there have been people in what is now California, the granite peaks of the Sierra Nevada have held masses of ice, according to new research that shows the glaciers have probably existed since the last Ice Age more than 11,000 years ago.

Good digital data is now being published that presents the scale of landscape change that occurred as a result of the Matai’an landslide hazard cascade. There is also interesting information about the root causes of the vulnerability of the town of Guangfu, where the fatalities occurred.

Some interesting information is now emerging about the Matai’an landslide and dam breach, much of it published in Taiwan in Mandarin. A very interesting post has appeared on the website of the Aerial Survey and Remote Sensing Branch that uses aerial imagery before and after the hazard cascade to analyse terrain changes. It is based upon this figure that they have published:-

Vertical elevation change before and after the Matai’an landslide and dam breach. Published by ASRS in Taiwan.

This uses LIDAR data from before and after the sequence of events, which has been turned into one metre Digital Elevation Model, which have then been digitally compared. Note this gives vertical change.

In the source area of the landslide, where the topography is extremely steep, there is over 300 metres of elevation reduction. Downslope and in the area of the dam and lake, the elevation change is over 200 m of accumulation – this is the landslide debris, whivch will now be mobilised in successive rain storm events. In the main channel, the river bed has aggraded (increased in elevation) by over ten metres, although the analysis shows that at point C this was 52 metres! This is going to cause very substantial issues in the future unless a large scale mitigation exercise is undertaken.

The cross-section through the landslide is fascinating:-

A cross-section showing vertical elevation change before and after the Matai’an landslide and dam breach. Published by ASRS in Taiwan.

This shows extremely well the rupture surface of the failure, which clearly had a rotational element, and the infilling of the bedrock topography by the landslide debris. Meanwhile, there is a good helicopter video on Facebook that shows the aftermath of the dam breach.

On a different matter, there is a huge amount of discussion in Taiwan as to why so little effort was made to mitigate the hazard associated with a breach of the Matai-an landslide dam. Writing in the Taipei Times, Michael Turton has a great article exploring the socio-political reasons why this disaster played out as it did. The bottom line is that Guangfu was built on a floodplain – a problem in so many places, but particularly acute in the almost uniquely dynamic physical geography of Taiwan. Levees were built to protect the town, which caused the river to aggrade even before the dam break event. And thus, the scene was set.

Hazards can be natural, disasters are not.

Return to The Landslide Blog homepage Text © 2023. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

A study published today in Earth System Dynamics provides a critical and previously underestimated connection between Antarctic sea ice, cloud cover, and global warming. This research is important because it shows that a greater extent of Antarctic sea ice today, compared to climate model predictions, means we can expect more significant global warming in the coming decades.

Publication date: Available online 24 September 2025

Source: Advances in Space Research

Author(s): M.A. Klyushin, A.A. Tikhonov

Publication date: Available online 24 September 2025

Source: Advances in Space Research

Author(s): Jun Huang, Xiaopeng Gong, Liwenle Liu, MengJiao LYU, Zheng Zhang, Shengfeng Gu, Yidong Lou

Publication date: Available online 24 September 2025

Source: Advances in Space Research

Author(s): Xuguo Shi, Yuan Jin, Daqing Ge, Wei Tang, Guijie Wang, Li Zhang, Shaocheng Zhang, Ling Zhang

Publication date: Available online 24 September 2025

Source: Advances in Space Research

Author(s): Mukulika Mondal, Jitesh Barman, A.K. Singh

Four of the most important interconnected parts of the Earth's climate system are losing stability, according to a review article based on observational data published in Nature Geoscience. The researchers succeeded in highlighting the warning signals for destabilization of the Greenland Ice Sheet, the Atlantic Meridional Overturning Circulation (AMOC), the Amazon rainforest, and the South American monsoon system.

A large proportion of the carbon dioxide emissions that are currently being released into the atmosphere by human activities are absorbed by the surface ocean, making it more acidic. As a result, the tiny organisms (plankton), which lie at the base of the marine food web and make the surface ocean their home, are at risk. The fossil record can tell us how these plankton responded during ancient intervals of climatic change that were similarly associated with increased carbon dioxide emissions.

Wildfire smoke causes more air pollution than current atmospheric models can predict. A new study by researchers at King Abdullah University of Science and Technology (KAUST) and the Chinese Academy of Sciences explains why by revealing that, under sunlight, wildfire smoke particles act like tiny chemical factories, producing harmful oxidants such as peroxides, a group of highly reactive pollutants contributing to smog and haze.

More than 90% of plastic waste ends up in the soil, where it breaks down into microplastics that are invisible to the naked eye. Microplastic pollution of the soil poses a severe threat to soil health as it can harm essential microbial communities and reduce crop yields. The presence of these tiny plastics may also worsen climate change by boosting the production of greenhouse gases, according to a new study published in Environmental Science & Technology.

A team of researchers at the University of Miami has developed a global atmospheric modeling framework that blends powerful research capabilities with accessibility for students and scientists alike.

body {background-color: #D2D1D5;} Research & Developments is a blog for brief updates that provide context for the flurry of news regarding law and policy changes that impact science and scientists today.

At 12:01 a.m. this morning, the U.S. federal government shut down. This shutdown comes after weeks of negotiations and pressure tactics failed to bring Congressional Republicans and Democrats together on a budget for the 2026 fiscal year or a continuing resolution to fund the government for a few more weeks.

The federal government has experienced numerous shutdowns over the past decade, the longest of which happened during the first Trump administration and lasted 35 days.

This shutdown, however, may be different, and far more devastating, for the federal workers, including scientists, who live and work across the nation.

In a typical shutdown, employees and contractors who are deemed nonessential to government function, including most workers at science and science-adjacent agencies, are furloughed (temporarily suspended) without pay. Those whose jobs are deemed essential work without pay. Employees receive backpay when the shutdown lifts, but contractors do not.

As of this morning, the shutdown has been proceeding as before.

“The plan to exploit a shutdown to purge federal workers is illegal, unconstitutional, and deeply disturbing.”

But experts are watching how the Trump administration proceeds, as, earlier this week, it ordered all agencies to prepare plans for mass firings and reductions in force (RIFs), not furloughs, should a shutdown occur. According to the White House’s Office of Personnel Management, RIF plans must work within the budget outlined by the President’s Budget Request (PBR). On top of this, thousands of federal workers took offers of deferred resignation earlier this year and have been on paid leave for months. With the shutdown, they may be officially out of jobs.

Exceptions to the shutdown include departments that align with the president’s agenda and received money from his domestic policy megabill, such as the Department of Defense and the Department of Homeland Security, along with a few essential services like Medicare and Social Security.

Trump had doubled down on the threat to fire federal employees yesterday afternoon, which spurred a set of federal employee unions to file a lawsuit alleging that the threats are an unlawful abuse of power.

“The plan to exploit a shutdown to purge federal workers is illegal, unconstitutional, and deeply disturbing,” Tim Whitehouse, the executive director of Public Employees for Environmental Responsibility, said in a statement. “To weaponize it as a tool to destroy the civil service would mark a dangerous slide into lawlessness and further consolidate power in the Executive Branch.”

 
Related

•  From the Prow: AGU Statement on the U.S. Government Shutdown
•  How the Shutdown Is Affecting Federal Services and Workers
•  U.S. Scientists Gird for Yet Another Government Shutdown
•  Government Shutdown Threatens Further Destruction of Environment and Science Agencies, Advocates Warn
•  Get Involved: AGU Science Policy Action Center
 

These mass firing plans, poised to radically downsize and reshape the federal government, have not yet been implemented and it’s unclear if or when that will change. In preparation for possible firings, the Interior Department instructed employees to take home government laptops and cellphones to be able to receive updates.

Nonetheless, until this shutdown is resolved many federal science agencies have largely ceased operations or are working with very limited capacity. Some agencies that have submitted revised shutdown plans, like NOAA and the U.S. Geological Survey, have not yet received approval for the plans, leaving significant uncertainty about what parts of an agency will be allowed to legally operate.

Below is a nonexhaustive list of science-related agencies and how they are being affected by the shutdown.

• Environmental Protection Agency (EPA): An updated contingency plan from the EPA, posted 30 September, is much the same as in past years. Research at the EPA was already suffering: Staff cuts to the agency’s research arm, the Office of Research and Development, are expected to set back much of the agency’s research into environmental hazards, for example.
  • Under the plan, about 89% of EPA staff are now furloughed.
  • The plan calls for a cessation of new grants, updates to the EPA website and communications, all Superfund cleanup activities not necessary to safeguard human lives, inspections of industrial sites, and issuance of permits. Any research and publication activities not deemed necessary to maintain critical operations (such as care for lab animals, plants, and maintenance of instrumentation) must cease as well. Although not mentioned in the current plan, The New York Times notes that during past shutdowns, most employees responsible for monitoring pollution and ensuring industry compliance were furloughed.
  • Past EPA employees think the shutdown could also derail administrator Lee Zeldin’s plans to restructure the agency and revoke landmark EPA rules, such as the 2009 Endangerment Finding.
• National Aeronautics and Space Administration (NASA):
  • Per NASA’s shutdown plan, less than 17% of essential personnel will remain at work, tasked with protecting mission-critical assets such as spacecraft in orbit, astronauts aboard the International Space Station, and other safety operations. Research activities, educational support, and NASA Center tours will cease. NASA Television and the NASA.gov website will not be updated. The agency has requested an exemption from furlough for operations related to upcoming Artemis missions. Although a bipartisan group of lawmakers included a request in a proposed continuing resolution that NASA follow funding guidelines set in the appropriations bill passed by the House of Representatives, for now NASA is following the more severe PBR. Federal whistleblowers recently reported that NASA was illegally implementing the PBR before now, so this shutdown might lead to many spacecraft and their operators being terminated.
  • Proposals for the next observing cycle of the James Webb Space Telescope are due 15 October. The Space Telescope Science Institute has extended the deadline for scientists affected by the shutdown.
• National Oceanic and Atmospheric Administration (NOAA) and National Weather Service (NWS): NWS was chronically understaffed before January 2025 and staffing problems have only gotten worse this year. The current shutdown will likely deepen the existing strain on NWS staff and slow down the hiring process for new meteorologists and forecasters.
  • NWS will continue to issue weather warnings and watches, including those related to developing Atlantic storms. NWS and NOAA tours, outreach, and educational activities will cease. Hurricane Hunter crew and maintenance workers are exempted from being furloughed. Flights are expected to continue. Many employees who operate NOAA satellites are exempted from being furloughed. NOAA satellite data should continue to flow. Most NOAA research activities will cease.
  • If NOAA implements firings in line with the PBR, research related to climate, weather and air chemistry, habitat conservation, ocean science, coastal conservation, and the Great Lakes would be eliminated, as would the Office of Oceanic and Atmospheric Research (OAR).
• National Park Service (NPS): The most recent NPS shutdown contingency plan is from March 2024.
  • Activities related to law enforcement, emergency response, fire suppression and monitoring, and public safety should continue. Most national parks are not expected to close. However, some former park superintendents have asked people not to visit due to safety concerns and bad public behavior during past shutdowns. Visitor centers, bathrooms, trash collection, and park ranger services are now unavailable in most locations. No staff are maintaining trails, clearing brush, or monitoring wildlife. The majority of NPS staff are furloughed and some may soon be laid off.
  • Access to some wildlife refuges has been restricted.
• National Science Foundation (NSF):
  • According to a 2023 contingency plan for the agency, no new grants, cooperative agreements, or contracts are being awarded, and no new funding opportunities issued. The agency’s plan also calls for responses to any questions about upcoming grant deadlines to pause, so calls and emails won’t be answered. Scientists are still free to complete work that has already been funded, and the Award Cash Management Service, responsible for disbursing already-awarded funds, will still operate. However, funding decisions have been halted or delayed. Websites such as Grants.gov and Research.gov remain operational and will accept materials, but processing of those materials will be delayed.
  • NSF scientists temporarily working at the agency but paid by their home institutions are continuing to work.
• U. S. Forest Service (USFS):
  • A 2024 contingency plan from the agency calls for more than half its staff to remain active, as thousands of employees have been deemed necessary to protect life and property. Some USFS work to manage forests, such as reducing hazardous fuels, running fire training, planting new trees, or supervising controlled burns, will continue. However, the 2024 plan states that an extended shutdown could delay these activities, possibly impacting fire risk over hundreds of thousands of acres of forest as windows of favorable burn conditions dwindle.
  • Per the 2024 plan, USFS science, including experiments that rely on specific timing, such as prescribed burn studies, may face delay or cessation.
• U.S. Geological Survey (USGS):
  • In the past, USGS shutdown plans have called for all employees who are not deemed necessary to protect human lives and property to be furloughed, resulting in about half of the agency’s staff temporarily losing their paychecks. According to past contingency plans, some research activities at USGS are supported by supplemental funding from laws such as the Infrastructure Investment and Jobs Act and the Inflation Reduction Act. Such projects can continue. However, much of the USGS’s monitoring and analyzing of Earth systems and natural resources will cease.
  • Online access to USGS maps, publications, and data may be limited, including water quality data and Landsat data critical for emergency response, agriculture, Earth science research, and more.

“It’s incredibly difficult to predict what the federal research enterprise might look like on the other side.”

We don’t know how long this shutdown will last. But the Office of Management and Budget’s posture means “there are likely to be more questions than answers about the operating status of science agencies,” Cole Donovan, associate director of science & technology ecosystems at the Federation of American Scientists, wrote in an email to Eos. “It’s incredibly difficult to predict what the federal research enterprise might look like on the other side.”

Eos will be following news related to this shutdown and monitoring impacts to the federal workforce and larger scientific community. If you have a tip, suggestion, or personal story to share about how this shutdown has affected you, please email us at eos@agu.org.

–Grace van Deelen (@gvd.bsky.social) and Kimberly M. S. Cartier (@astrokimcartier.bsky.social), Staff Writers

These updates are made possible through information from the scientific community. Do you have a story about how changes in law or policy are affecting scientists or research? Send us a tip at eos@agu.org. Text © 2025. AGU. CC BY-NC-ND 3.0
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California heads into the new water year facing continued risks from climate-driven extremes, the California Department of Water Resources said.

With unprecedented clarity, scientists have directly observed a subduction zone—the collision point where one tectonic plate dives beneath another—actively breaking apart. The discovery, reported in Science Advances, sheds new light on how Earth's surface evolves and raises fresh questions about future earthquake risks in the Pacific Northwest.