Preprints
Filtering by Subject: Oceanography and Atmospheric Sciences and Meteorology
The impact hypothesis as a mechanism for the origin of the Amazon basin - analysis of antipodal impacts of celestial bodies and their impact on global morphotectonics
Published: 2025-04-23
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics
The Amazon Basin is the largest fluvial system on Earth, yet its central subsidence and asymmetrical drainage pattern remain partially unexplained by traditional geological models. This study introduces a novel impact-based hypothesis, proposing that the Amazon depression is a result of tectonic deformation at the intersection of seismic shockwaves originating from two major planetary impacts: [...]
A realistic climate strategy
Published: 2025-04-12
Subjects: Climate, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Sciences, Environmental Studies, Oceanography and Atmospheric Sciences and Meteorology, Social and Behavioral Sciences, Sustainability
The international climate strategy is failing. Current policies will act too slowly to prevent rising temperatures from crossing critical climate tipping points. IPCC assessments underestimate the non-linear risks and catastrophic costs of overshooting Paris Agreement targets. Opponents of solar geoengineering cite concerns about moral hazard and other potential risks; however, at this juncture [...]
Impact of Marine Heatwaves and Coldwaves on CO2 in the South China Sea
Published: 2025-04-10
Subjects: Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
Global warming is increasing the frequency and intensity of marine heatwaves (MHWs) in the South China Sea, while marine cold waves (MCWs) occur intermittently. Both phenomena influence the air-sea CO2 flux (FCO2) at the air-sea interface. This study uses inversion and reanalysis data, along with FCO2 diagnostic methods, to assess their impact on FCO2 in the South China Sea from 2003 to 2019. The [...]
dageo: Data Assimilation in Geosciences
Published: 2025-04-08
Subjects: Earth Sciences, Mining Engineering, Oceanography and Atmospheric Sciences and Meteorology, Other Engineering
Data Assimilation combines computer models with real-world measurements to improve estimates and forecasts of dynamical systems such as oceans, atmosphere, and subsurface reservoirs. The Python package dageo is a tool to apply data assimilation in geoscience applications. Currently, it encompasses the Ensemble Smoother with Multiple Data Assimilation (ESMDA) method and provides tools for [...]
Mid-Ocean Ridge Volcanism (Encyclopedia of Volcanoes, 3rd edition, book chapter)
Published: 2025-03-26
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The vast majority of the Earth’s volcanism takes place in the deep ocean along mid-ocean ridges (MORs), yet because it is difficult to detect and observe, it is also relatively poorly understood. MOR volcanism occurs where tectonic plates spread apart and mainly produces effusive basaltic fissure eruptions where dikes reach the surface. The character and frequency of volcanism varies greatly as a [...]
An Improved Methodology to Estimate Cross-Scale Kinetic Energy Transfers from Third-Order Structure Functions using Regularized Least-Squares
Published: 2025-03-25
Subjects: Analysis, Applied Statistics, Fluid Dynamics, Longitudinal Data Analysis and Time Series, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Statistical Methodology, Statistical, Nonlinear, and Soft Matter Physics
Several methods exist for estimating cross-scale kinetic energy (KE) transfers; however, they are ill-adapted for sparse ocean observations, hindering the study of oceanic KE transfers. A newly developed third-order structure function $D3(r)$ framework allows estimation of KE injection rates $\epsilon_j(k)$ and KE transfers $F(k)$ across scales using sparse data. This approach requires inverse [...]
Weakening of AMOC linked to past Greenland Ice Sheet retreat
Published: 2025-03-21
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Geochemistry, Geology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Paleontology, Physical Sciences and Mathematics
A weakening of the Atlantic Meridional Overturning Circulation (AMOC) is predicted to occur under multiple scenarios of future warming. However, the effect of meltwater from a decaying Greenland Ice Sheet (GrIS) on AMOC is uncertain. Using a basin-wide network of North Atlantic sediment cores, we show that the largescale melting of the GrIS during a previous interglacial (Marine Isotope Stage 11c [...]
Resolved tropical cyclones trigger CO2 uptake and phytoplankton bloom in an Earth system model simulation
Published: 2025-03-18
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology
The ocean carbon cycle is directly impacted by storms in the atmosphere. Tropical cyclones (TCs), particularly, are known to drive intense air-sea CO2 fluxes and to trigger phytoplankton blooms. However, the latest generation of Earth system models (ESM) cannot realistically represent TCs due to their coarse spatial resolution (typically 100-200 km grid spacing). Here, we present the first [...]
Large reductions in United States heat extremes found in overshoot simulations with SPEAR
Published: 2025-03-18
Subjects: Atmospheric Sciences, Climate, Meteorology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Increases in the intensity and frequency of heatwaves are already evident in the observational record, and these increases are expected to be further amplified in future climate projections with greater radiative forcing. However, it is unclear how temperature extremes will respond regionally to emissions reductions and declines of greenhouse gases later in the 21st century, such as through the [...]
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 [...]
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 [...]
Generative Data Assimilation for Surface Ocean State Estimation from Multi-Modal Satellite Observations
Published: 2025-03-05
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Estimating the surface ocean state at mesoscale eddy-resolving scales is essential for understanding the role of eddies in climate and marine ecosystems. Satellites provide multi-modal observations through sea surface height, temperature (SST), and salinity (SSS). However, each variable is observed with varying resolutions and sparsity, while some variables, such as surface currents, are not yet [...]
Reduced Precipitation on Rapa Nui During the Decline of the Moai Culture
Published: 2025-03-04
Subjects: Atmospheric Sciences, Climate, Environmental Sciences, Environmental Studies, Geography, Human Geography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
From approximately 1200-1600 CE, Polynesian settlers on the island of Rapa Nui engaged in megalithic monument construction, crafting hundreds of Ahu platforms and Moai statues from volcanic bedrock. The decline of this tradition has intrigued archaeologists for decades. The most widely disseminated hypothesis surrounding the demise of the Ahu Moai culture suggests that the Rapanui overexploited [...]
Airborne remote sensing of concurrent submesoscale dynamics and phytoplankton
Published: 2025-02-11
Subjects: Oceanography and Atmospheric Sciences and Meteorology
Submesoscale dynamics can induce significant vertical fluxes of phytoplankton, nutrients, and carbon, resulting in biological and climatological impacts such as enhanced phytoplankton production, phytoplankton community shifts, and carbon export. However, resolving these dynamics is challenging due to their rapid evolution (hours to days) and small spatial scales (1-10 km) of variability. The [...]
Recent rise of water levels of Lake Nakuru, Kenya: Unraveling the Changing Precipitation Regime and its Climatic Drivers
Published: 2025-01-21
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Engineering, Environmental Engineering, Meteorology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology
The Kenyan Rift Valley has experienced an abrupt and significant rise in its lake levels since 2010, followed by a more rapid rise since 2020. This paper examines the dynamic changes in precipitation patterns and their climatic drivers in the Kenyan Rift Valley region from 1981 to 2021, focusing on Lake Nakuru. Notably, in 2010, a pivotal change point in precipitation aligns with the rising water [...]