Preprints
Filtering by Subject: Oceanography and Atmospheric Sciences and Meteorology
ENSO, weather regimes, and U.S. heating degree days
Published: 2026-09-03
Subjects: Oceanography and Atmospheric Sciences and Meteorology
Heating degree days (HDDs; the number of degrees by which average daily temperature falls below 65°F) quantify heating demand and are used to manage weather-related financial risk. Here we examined the relation of El Niño–Southern Oscillation (ENSO) with U.S. cold-season HDDs over the period 1979–2026 in NOAA Climate Division data and observations from stations that are used to settle publicly [...]
Super El Niño Winters and the Arctic Polar Vortex: Response Heterogeneity, QBO Modulation, and a Prospectively Defined Test for Winter 2026/27
Published: 2026-08-30
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Other Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
In the three strongest El Niño winters of the instrumental record (1982/83, 1997/98, 2015/16) the Arctic polar vortex did not collapse in a major midwinter sudden stratospheric warming (SSW). This study starts from the premise that the observation is not a paradox: 58% of El Niño winters contain at least one major SSW, so the chance probability of three consecutive SSW-free winters is 0.42³≈0.07, [...]
Deep Learning-Based Meteorological Data Downscaling: A Comparative Study with Physics Informed CNN and a Component-Level Ablation Analysis
Published: 2026-08-29
Subjects: Computer Engineering, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Meteorological statistical downscaling is a critical technique for deriving high-resolution climate information from coarse global reanalysis products. This experiment investigates the application of five representative deep learning architectures for downscaling ERA5 reanalysis 2m temperature fields from 1° to 0.25° spatial resolution (4x upscaling factor) over the China region, spanning the [...]
A Reduced-Order Dynamical Model for the Ignition of Diver-Induced Cohesive Silt-Out on Sloping Beds
Published: 2026-08-28
Subjects: Applied Mathematics, Dynamical Systems, Dynamic Systems, Non-linear Dynamics, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Ordinary Differential Equations and Applied Dynamics, Physical Sciences and Mathematics
A downward fin thrust near a cohesive seabed lofts sediment. Whether this cloud settles or organizes into a self-sustaining down-slope current determines if a diver loses visibility briefly or catastrophically. We reduce the layer-averaged balances of fluid mass, sediment mass, and momentum to a temporal slab of fixed thickness in the weakly entraining limit. This yields an autonomous planar [...]
Quantifying onset period rather than single date reveals projected intensification of dry-to-wet season transition.
Published: 2026-08-28
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology
Recent years have seen increasingly frequent delayed rainfall onset, especially in South America (SAm) and Southern Africa (SAfr). This arrival of the wet season is critical to water resources, ecosystems, and rain-fed agriculture. Existing rainfall-based approaches define the rainfall onset by a single date, limiting their ability to characterise the progression into the wet season. We introduce [...]
RainCheck Africa: A Systematic Review and Meta-Analysis of Gridded Precipitation Dataset Performance at Continental Scale
Published: 2026-08-26
Subjects: Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
Gridded rainfall products are indispensable for water resource management, agricultural monitoring, and disaster risk reduction across Africa, yet no systematic synthesis of their performance has been conducted. We present RainCheck Africa: a PRISMA-compliant systematic review and meta-analysis of 72 peer-reviewed studies published between 2015 and 2025 evaluating satellite, reanalysis, and [...]
Numerical modeling and hazard analysis of Kuwait dust storm events using WRF Chemistry model
Published: 2026-08-26
Subjects: Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics
Dust storms have a negative impact on socio-economic events in Kuwait, including traffic accidents, seaport closures, airport shutdowns, and flight delays, and agriculture degradation. From the diurnal analysis of weather parameters, it was noticed that dust storms were more severe from noon to late evening hours and gradually slowed down during the night hours. Sometimes, these strong dust [...]
The limits of ecological decodability of a geospatial foundation-model embedding: a registered evaluation of AlphaEarth over shallow Great Barrier Reef habitats
Published: 2026-08-25
Subjects: Environmental Monitoring, Environmental Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Annual satellite embedding fields compress a year of multi-sensor observation into one vector per 10 m pixel, worldwide. We test what ecological information the AlphaEarth embedding holds about shallow (< 10 m) Great Barrier Reef habitats, and where its limits lie. Every candidate output was registered with a pass gate before testing, evaluated under one fixed protocol, and reported pass or [...]
Boxology: the isobar–thickness box count as an exact advection integral, and its rendering
Published: 2026-08-24
Subjects: Atmospheric Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology
"Boxology" is the hand-analysis practice of reading thermal advection from the angle at which mean-sea-level-pressure isobars cross 1000-500 hPa thickness contours: steep crossings cut the chart into small quadrilaterals and imply strong advection, parallel families imply none. This note shows the practice is an identity within geostrophic balance rather than a rule of thumb, and implements it as [...]
Adalar at the Eastern Marmara Seismic Gap: The August 2026 Earthquake Cluster and Its Implications for Seismic Hazard near Istanbul
Published: 2026-08-20
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering Science and Materials, Environmental Sciences, Geotechnical Engineering, Higher Education, Oceanography and Atmospheric Sciences and Meteorology, Other Engineering, Risk Analysis, Science and Mathematics Education, Structural Engineering
The eastern Marmara Sea and Adalar sector lie close to İstanbul and the western North Anatolian Fault, where earthquake-source processes interact with strong basin and site effects. This study integrates a reconciled earthquake catalog, waveform-quality measures, spatial statistics, trial hypocentral relocation, reconnaissance focal mechanisms, point-source Coulomb stress screening, and published [...]
ECMWF SEAS5 Seasonal Precipitation Outlook and Hydrological-Hydrogeological Assessment for the Middle East: August 2026-January 2027
Published: 2026-08-16
Subjects: Agriculture, Earth Sciences, Environmental Sciences, Food Science, Higher Education, Oceanography and Atmospheric Sciences and Meteorology, Risk Analysis
This preprint presents a regional hydrological and hydrogeological interpretation of the ECMWF SEAS5 System 51 ensemble-mean precipitation forecast initialized on 1 August 2026 for the Middle East and adjacent portions of the analysis domain. The supplied NetCDF field is time-mean total precipitation rate (tprate; m s^-1), converted to monthly precipitation depth (mm/month) using the actual [...]
Source-composition sensitivity in historical marine wind observations: a CLIWOC case study, 1750--1855
Published: 2026-08-15
Subjects: Climate, Earth Sciences, Environmental Monitoring, Environmental Sciences, Environmental Studies, Library and Information Science, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Other Applied Mathematics, Other Computer Sciences
Recovering Climate’s History with Artificial Intelligence used the CLIWOC ship-logbook database to argue that sailors’ wind observations reveal a previously undetected shift in global atmospheric circulation between the late eighteenth and early nineteenth centuries. We reproduce the article's principal annual aggregate from CLIWOC release 2.1 and find that this unstandardized, record-weighted [...]
ECMWF SEAS5 Seasonal Precipitation Outlook and Preliminary Rainfall-Based Flood Screening for Iraq: October 2026–January 2027
Published: 2026-08-12
Subjects: Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Risk Analysis
This preprint provides a hydrological and hydrogeological interpretation of ECMWF SEAS5 monthly precipitation forecasts for Iraq from October 2026 through January 2027. The analysis uses the ECMWF System 51 ensemble mean initialized on 1 August 2026. The downloaded time-mean total precipitation rate was converted from metres per second to monthly precipitation depth in millimetres using the [...]
Questioning the Ferromanganese Nodule Dark Oxygen Production Hypothesis
Published: 2026-08-04
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Statistical projections of the mean changes in intra-seasonal rainfall characteristics over Zambia from the reference period 1981-2010 to the future 2031-2060.
Published: 2026-07-30
Subjects: Oceanography and Atmospheric Sciences and Meteorology
Zambia's rain-fed agriculture depends less on how much rain falls in a season than on how that rain is distributed within it. This study projects changes in the longest dry spell (consecutive dry days, CDD) and the longest wet spell (consecutive wet days, CWD) over Zambia, together with the number of wet days, rainfall per wet day and seasonal total, for 2031–2060 relative to 1981–2010, using 25 [...]