Preprints
There are 5647 Preprints listed.
Summertime sediment storage on the Alaskan Beaufort Shelf and implications for ice-sediment rafting and shelf erosion
Published: 2025-03-14
Subjects: Physical Sciences and Mathematics
Arctic coastlines are known to be rapidly eroding, but the fate of this material in the coastal ocean (and the sedimentary dynamics of Arctic continental shelves in general) is less well-constrained. This study used summertime mooring data from the Alaskan Beaufort Shelf to study sediment-transport patterns which are dominated by waves and wind-driven currents. Easterly wind events account for [...]
Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps
Published: 2025-03-14
Subjects: Physical Sciences and Mathematics
Methane forms beneath ice sheets through microbial methanogenesis and thermogenic breakdown of organic matter, creating a potentially large greenhouse gas reservoir prone to release during glacial retreat. Subglacial thermogenic methanogenesis can increase gas buildup and create oases for life, but this process has not yet been observed in Antarctica, contributing to uncertainty in the spatial [...]
Collaborative Assessment of a Large-Scale Integrated Landscape Restoration Project in the Steep-Slope Regions of Central Africa
Published: 2025-03-14
Subjects: Engineering, Life Sciences
Landscape restoration projects are among the most extensive conservation actions at the global level that have been promoted in the last three decades. Such projects, however, cannot exclusively be based on the restoration of natural and semi-natural ecosystems, but should focus on a cultural landscape approach balancing environmental and socio-economic needs. One of the largest restoration [...]
Ediacaran coupling of climate and biosphere dynamics
Published: 2025-03-14
Subjects: Climate, Glaciology, Paleontology, Sedimentology, Stratigraphy
Throughout the Phanerozoic (538.8 Ma to present), climate change is demonstrably linked to radiations, extinctions, and turnovers in the biosphere. Here, we show that this connection existed in the late Ediacaran (~579 to 538.8 Ma), the first interval in Earth’s history to host complex macro-organisms, including early metazoans. Current correlations of glacial sedimentary deposits have been used [...]
Solar control of global mean temperature outweighed since 1940s by anthropogenic warming (by airborne soot, not CO2): literature synthesis
Published: 2025-03-14
Subjects: Oceanography and Atmospheric Sciences and Meteorology
Primarily solar control of global warming and cooling for the last 9,000 years is proven by the striking likeness between published graphs of (1) average near-surface air temperature (from proxies and, since 1880, NASA-GISS thermometer data) and (2) solar-magnetic output. Graph-to-graph visual cross-matching of spikes (peaks, troughs) and of multi-century trends reveals a ~150-year temperature [...]
Hothouse hydrology: Evolving river dynamics in the Eocene Montllobat and Castissent Formations, Southern Pyrenees
Published: 2025-03-14
Subjects: Physical Sciences and Mathematics
Environmental forcings have shaped landscapes and basins across geologic history, and Earth’s surface is projected to undergo rapid change in the near future amidst increasing climate extremes. Rivers are highly sensitive to climate and tectonic change, and understanding how fluvial systems respond to greenhouse climates in dynamic tectono-geomorphic settings is vital to projecting imminent [...]
Mercury budget in global rivers at present-day: impacts from reservoirs and dams
Published: 2025-03-14
Subjects: Biogeochemistry, Earth Sciences, Environmental Health and Protection, Environmental Monitoring, Environmental Sciences, Water Resource Management
Many world rivers are currently polluted by mercury (Hg) compounds, leading to the bioaccumulation of methylmercury (MeHg) in the food web, which poses potential health risks to humans. However, the riverine Hg budgets of global scale remain poorly understood due to limited observations, complicating efficient environmental governance. Here, we employ a process-driven Hg model to track its [...]
Plausible global emissions scenario for the 2℃-target aligned with China’s net-zero pathway
Published: 2025-03-11
Subjects: Earth Sciences
Due to sizeable anthropogenic CO2 emissions, China’s transition towards carbon neutrality will fundamentally alter global CO2 emissions, providing critical insights into warming levels, extreme events, overshoot, tipping points, and regional climate impacts. Existing emission scenarios that fail to reflect this transition increasingly diverge from reality. To bridge this gap, we developed an [...]
Is abyssal dark oxygen production even possible at all?
Published: 2025-03-10
Subjects: Chemistry, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Physical principles need to be respected when interpreting controversial findings such as the production of abyssal oxygen. Such extraordinary claims must be analysed carefully before a large research effort is mounted and valuable human and financial resources are wasted based on flawed data. We are aware of the sensitivities around polymetallic nodules and their potential value as a source of [...]
Modern Cave Monitoring Informs Interpretations of Past Climate Change: Applications to Titan Cave, Wyoming
Published: 2025-03-10
Subjects: Earth Sciences, Environmental Monitoring, Environmental Sciences, Geochemistry, Geology, Geomorphology, Hydrology, Speleology
Monitoring of cave environments is an essential process for deciphering records of past climate change preserved in the geochemical composition of speleothems, or mineral cave deposits. This study presents data from a multi-year monitoring effort in Titan Cave, Wyoming, a site of interest due to the abundance of speleothems suitable for paleoclimate reconstruction. Titan Cave exhibits annual cave [...]
Persistent high-pressure magma storage beneath a near-ridge ocean island volcano (Isla Floreana, Galápagos)
Published: 2025-03-09
Subjects: Physical Sciences and Mathematics
Volcanic evolution in ocean island settings is often controlled by variations in the chemistry and volumetric flux of magma from an underlying mantle plume. In locations such as Hawaiʻi or Réunion, this results in predictable variations in magma chemistry, the rate of volcanic activity, and the depth of magma storage with volcanic age and/or distance from the center of plume upwelling. These [...]
Fracturing during freezing in salty ice: preliminary analysis using a low-cost model system
Published: 2025-03-08
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
The fracture properties of saline water ice play an important role in governing the mechanical behavior of sea ice, marine ice sheets, and icy planetary bodies. Here, we design a low-cost experimental system based on a simple observation: fractures form when freshwater is frozen in a plastic bag, but do not form when a small amount of NaCl salt (several g/L) is added before freezing. We [...]
A comment on the indicator capacity of Artemisia pollen in pre-Holocene paleoecology
Published: 2025-03-07
Subjects: Paleontology
In pre-Holocene paleoecology, Artemisia (Asteraceae) pollen is commonly considered an indicator of arid steppic environments in temperate regions. However, the >520 known species of this genus occur across a wide range of bioclimatic conditions. This paper comments on a recent comprehensive study that examined the identification of Artemisia pollen at the species level in relation to the [...]
Drastic Changes in Atmospheric CO2 Concentration Led to Biological Mass Extinction and Explosion
Published: 2025-03-07
Subjects: Earth Sciences, Environmental Sciences, Paleontology
When the area of polar ice caps expands to a certain threshold, a positive feedback effect will occur. Due to the strong reflection of sunlight by ice and snow, the global climate will become cold and dry. CO₂ in the atmosphere will be rapidly sequestered in the seabed and permafrost through the biological carbon pump, thereby affecting plant photosynthesis, reducing NPP and the nutritional value [...]
Improved LA-Q-ICP-MS U-Pb Zircon Age Estimates for Young (< 10 Ma) Zircons & Quantification of Bias in CL Guided Spot Selection
Published: 2025-03-07
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
We present a new approach to reducing U-Pb data from zircons obtained by laser ablation-quadrupole-inductively coupled plasma-mass spectrometry (LA-Q-ICP-MS), with emphasis on young (< 10 Ma) zircons. In young zircons the 207Pb yield is extremely low, generating a relatively high abundance of zero values during analyses. This impacts the use of 207Pb/206Pb in application of Tera-Wasserburg [...]