[Microbiome] Background: Iron, the most abundant redox-active metal in the Earth’s crust, is coupled to numerous biogeochemi- cal cycles. However, the mechanisms of iron oxidation and the organisms involved remain […]
snowball earth
![Meridional overturning streamfunction (Ψ). Meridional sections of zonally–integrated streamfunction (Sverdrups, 1 Sv ≡ 10 6 m 3 s−1 ) in the (a) IG_Ctrl, (b) Glac_Ref, (c) IG_N50, and (d) IG_N100 simulations. Positive (red) values denote clockwise overturning, while negative (blue) values denote counterclockwise overturning. The apparent diapycnal transport at ~60°S in (a) IG_Ctrl and (c) IG_N50 may be related to the effect of standing meanders [see Jansen (2017)] but does not impinge upon our results. -- Journal of Climate](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/New-discovery.png?resize=1200%2C720&ssl=1)
Posted inIcy Worlds
New Discovery Links Hemispheres In The Mystery Of Earth’s Past Ice Ages
[University of St. Andrews] New research from the University of St Andrews has uncovered a thus unknown process which may have helped drive the Earth in to past ice ages.
![Percentage of 1,000 stochastic paths that converge shown as color maps for e “ 0.1, 0.3. The two bracketed values in the title of each sub-figure are the critical deterministic values of S ˚ for convergence and bifurcation given in Table A.2. The white and black horizontal lines are the convergence and bifurcation values respectively. Additional figures are found in the Supplementary Material (Appendix C). -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Stochastic-Snowball.png?resize=1200%2C720&ssl=1)
Posted inBiogeochemical Cycles & Geobiology
Stochastic Snowball States in Planetary Climate
[astro-ph.EP] Motivated by the recent finding of Ji and Abbot (2025) that at moderate eccentricity (0.2–0.3) the planetary Snowball bistability vanishes, we have introduced stochasticity of the orbital eccentricity into […]
Posted inBiogeochemical Cycles & Geobiology
Material Cycling Across Earth’s Spheres And Triggers Of Cambrian Explosion: A Tectonic Perspective
[ELSP] A comprehensive model of the Cambrian explosion featuring “multi-factors coupling and multi-sphere driving”. Supercontinent breakup and mantle plume activity served as the initial trigger of environmental change in the […]
Posted inIcy Worlds
Amplified Cooling Of Snowball Earth From A Salt-albedo Feedback
[Climate of the Past] It is believed that the atmospheric circulation on Snowball Earth produced a net ablation zone exposing bare sea ice.
![This illustration contrasts Earth's oceans during ancient glaciations (left) with deglacial conditions (right). Syracuse University researchers found that oceans lost oxygen not just during warm periods, but repeatedly during Earth's deepest ice ages, a pattern preserved in manganese deposits within ancient seafloor rock. (Courtesy: Xubin Wang, generated with AI)-- [Syracuse University]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Metal-deposits.jpg?resize=1200%2C720&ssl=1)
Posted inBiogeochemical Cycles & Geobiology
Metal Deposits Linked To Oceanic Oxygen Loss During Ancient Ice Ages
[Syracuse University] An international team of researchers analyzed manganese and other chemical signatures preserved in more than 27,000 ancient seafloor samples collected from six continents. Across six major glaciations spanning […]
Posted inAway Teams & Field Reports, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extinction events, Fossils & Paleontology, Habitable Zones, Mapping, Geodesy, Cartography, Bathymetry, Origin & Evolution of Life, Press Release, Sample Return
Early Complex Earth Life Clung To Oxygenated Seafloors For Hundreds Of Millions Of Years
From the highest mountains to the deepest ocean, the driest desert to the lushest jungle, Earth displays a dazzling array of lifeforms. And eukaryotes account for many of these lifeforms, […]
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Cryobiology, Extinction events, Gaia - Planetary Perspectives, Habitable Zones, Icy Worlds, Mapping, Geodesy, Cartography, Bathymetry, Polar / Alpine Expeditions, Press Release, Robotics/Rovers/UAVs, Sample Return
A New Explanation For Snowball Earth
A new study by Earth scientists in the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) offers an explanation for one of Earth’s great climate puzzles: how […]
![Maps of GEOCLIM simulation (two time slices). “0” maps (left column) are the initial condition, “1” maps (right column) are at the perturbation peak (3 Myr of run time, cf Fig. 4a). (a0–1) Topography and oceanic O2 concentration at bottom of water column, (b0–1) physical erosion rate, showing enhanced physical erosion around the Variscan orogeny, and (c0– 1) regolith depletion quantified by the proportion of unweathered mineral at top of regolith. The uplifted area is contoured in magenta on each map. The boundaries of oceanic boxes, and their corresponding continental drainage basins are drawn on each map (white solid and blue dotted lines). GEOCLIM computes one mean O2 concentration for each of the 21 boxes. The maps panels (a0–1) show the mean concentrations of GEOCLIM bottom boxes drawn on the full geographic extent of these boxes at the oceanic resolution of the FOAM ocean-atmosphere general circulation model [90] simulations, which were used as GEOCLIM forcing. -- Science China Press](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/04/What-triggered-Earths.png?resize=1200%2C720&ssl=1)
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Habitable Zones, Icy Worlds, Press Release
What Triggered Earth’s Shift From A Greenhouse To An Icehouse Climate And The Onset Of The Late Paleozoic Ice Age?
Scientists have debated for decades what caused the Late Paleozoic climate transition from a greenhouse to an icehouse state ~350 million years ago. Some invoke a pronounced increase in continental […]
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Habitable Zones, Icy Worlds, Status Report, Terraforming & Geoengineering, Water/Hycean Worlds & Oceanography
Climate And Ocean Circulation Changes Toward A Modern Snowball Earth
It has been hypothesized that the Earth may have experienced snowball events in the past, during which its surface became completely covered with ice. Previous studies used general circulation models […]