All articles tagged with #carbon cycle
A new PLOS Biology study shows fungi in Arctic fjord waters and sediments play a significant role in storing carbon by taking up dissolved amino acids and converting organic matter into biomass, challenging the idea that bacteria dominate marine carbon cycling and highlighting fungi as key agents of carbon sequestration in fragile Arctic ecosystems.
University of Michigan researchers sampled water from 500 meters below ground and identified 689 fungal species (13 new), plus tardigrades and worms, in a thriving deep subterranean ecosystem that may influence carbon release and storage in shale, challenging the assumption that deep subsurface carbon is inert and prompting a rethink of carbon cycling models.
A University of Michigan study of water brought up from the Antrim Shale beneath Michigan found surprisingly rich life in deep underground groundwater: one drop contained about 250 fungal cells and 689 fungal species (13 new), plus tardigrades (water bears) and tiny segmented worms, indicating an active underground food web and potential importance for Earth's carbon cycle. Isotope data suggest the ancient water last contacted surface about 11,000 years ago, and researchers are cultivating deep-subsurface fungi and developing tools to study these hidden ecosystems further.
Phytoplankton in the sunlit ocean produce about half of Earth's oxygen via photosynthesis, but net atmospheric oxygen is the result of production minus respiration and decay; the ocean's microscopic, fast-renewing layer spans vast areas and can rival terrestrial forests in scale, with light, nutrients and water mixing governing where it happens. Satellites like NASA's PACE estimate productivity, but warming and nutrient pollution could reshape carbon cycling and marine ecosystems, underscoring the ocean as a giant, invisible engine linking sunlight, oxygen and food.
A Nature Communications study finds that tiny deep-ocean turbulence rapidly distributes heat, nutrients and carbon, influencing sea level rise and fisheries on decadal scales—far faster than current climate models capture. By tracing chlorofluorocarbons, researchers show deep waters move heat and carbon around on timescales relevant to human life, underscoring gaps in climate projections and the need for improved understanding and monitoring of small-scale ocean mixing to inform policy.
New research using rhenium isotopes from a 183-million-year-old Welsh rock core shows that oxidation of eroding organic carbon amplified the Toarcian warming, indicating organic-carbon weathering can release CO2 and strengthen climate feedbacks beyond volcanic CO2; the exact magnitude and relevance to modern climate remain uncertain.
A Nature study across 50 rivers on China's Qinghai–Tibet Plateau shows that thawing permafrost accelerates rock weathering, which consumes atmospheric CO2 and can offset or even exceed river CO2 emissions in some catchments, suggesting geological processes may partly counterbalance thaw-induced carbon release.
A global study maps arbuscular mycorrhizal fungal networks using 16,669 soil cores and AI, revealing dense underground hyphal networks that connect most land plants and drive carbon and nutrient exchange. Wild grasslands host the densest networks, with topsoil containing a large share of global fungal biomass, and croplands showing about 50% lower density. If laid end-to-end, the hyphae would stretch about 68 quadrillion miles (110 quadrillion kilometers), roughly 10% of the Milky Way’s width, highlighting their key role in the carbon cycle and informing biodiversity, climate, and agricultural strategies.
Scientists using machine learning and high-resolution imaging mapped the planet's vast underground networks of arbuscular mycorrhizal fungi, finding filaments totaling about 68 quadrillion miles and storing around 300 megatons of carbon—roughly 4-6 times the carbon contained by all humans—highlighting fungi's key role in plant nutrition and global carbon cycling.
A sweeping look at Earth’s deep ocean—from twilight mid-water zones to hydrothermal vents—reveals an enormous, little-understood ecosystem that fuels global climate and hosts bizarre life forms powered by chemical energy. It traces a century of exploration (Challenger, Alvin) and explains how mid-water migrations drive major carbon transport, while warning that growing seabed‑mining interests, especially for manganese nodules in the Clarion–Clipperton Zone, threaten fragile, slow‑growing communities and untapped biotechnologies. The piece argues for protecting these environments even as they hold clues to life’s origins and future innovations.
Rocks show that early Mars hosted liquid water, but whether it was warm remains debated. The planetary dynamo likely died between about 4.2 and 3.7 billion years ago, removing the magnetic shield and enabling solar wind to strip gas—an escape process MAVEN measured, especially during solar storms. Some carbon dioxide may have been stored in minerals like siderite, so not all missing air left to space. The balance between atmospheric loss and crustal storage is still uncertain, and better palaeomagnetic dating and additional sampling are needed to pin down Mars’ climate history. The cold desert is settled, but the path to understanding how it happened is ongoing.
Harvard researchers simulate the Sturtian glaciation (about 717–660 million years ago) as a cycle of glaciation and thaw driven by carbon-cycle feedbacks: volcanic CO₂ input and basalt weathering lowered CO₂ to trigger ice cover, while ongoing volcanism and reduced weathering during ice cover allowed CO₂ to build and melt, repeating for ~56 million years—reconciling the geological record and the survival of early aerobic life, with implications for exoplanet climates.
A University of Washington study finds that an Earth-sized planet needs a substantial surface water inventory—about 20–50% of Earth’s ocean volume—to maintain long-term habitability. On very dry worlds, the carbon cycle can break down, allowing CO2 to build up and heat the planet, potentially rendering it uninhabitable despite being in the habitable zone. Venus serves as a nearby analog, illustrating how small water differences can dramatically impact climate. The work suggests many desert-like exoplanets thought promising for life may actually be poor candidates and informs future observations and Venus missions.
A new study using computer models shows that Earth's plate tectonics—especially mid-ocean ridges and continental rifts—play a larger role in shaping global climate than previously thought by guiding the deep carbon cycle: carbon stored in seafloor sediments is buried and later released via subduction, driving greenhouse and icehouse periods over the last 540 million years and challenging the view that volcanic arcs are the primary CO2 source, with implications for future climate models.
Scientists using the NEPTUNE observatory monitored Barkley Canyon for nearly 10 years and found an unexpected absence of decay activity around whale bones and wood, lacking typical scavengers and bone-eating organisms. The results suggest ocean deoxygenation and expanding oxygen minimum zones are suppressing the deep-sea recyclers (Osedax, Xylophaga), potentially slowing organic decomposition and nutrient cycling with ripple effects on the broader food web.