Preprints
Filtering by Subject: Oceanography and Atmospheric Sciences and Meteorology
Data from the drain: a sensor framework that captures multiple drivers of chronic coastal floods
Published: 2022-04-02
Subjects: Earth Sciences, Environmental Monitoring, Environmental Sciences, Hydrology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Tide gauge water levels are commonly used as a proxy for flood incidence on land. These proxies are useful for projecting how sea-level rise (SLR) will increase the frequency of coastal flooding. However, tide gauges do not account for land-based sources of coastal flooding and therefore flood thresholds and the proxies derived from them likely underestimate the current and future frequency of [...]
A state estimate of Siberian summer temperature and moisture availability during the Last Glacial Maximum combining pollen records and climate simulations
Published: 2022-03-27
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology
The Last Glacial Maximum (LGM, ~21.000 years before present) was a period with significantly lower global mean temperature, large Northern Hemisphere ice sheets, and low CO2 concentrations. Unlike other high-latitude areas, Siberia was not covered by a terrestrial ice sheet. Climate simulations with LGM boundary conditions show large inter-model differences especially in Northern Siberia, which [...]
Controls on surface warming by winter Arctic moist intrusions in idealized large-eddy simulations
Published: 2022-03-25
Subjects: Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The main energy input to the polar regions in winter is the advection of warm, moist air from lower latitudes. This makes the polar climate sensitive to the temperature and moisture of extra-polar air. Here, we study this sensitivity from an air-mass transformation perspective. We perform simulations of an idealized maritime air mass brought into contact with sea ice employing a three-dimensional [...]
Automated machine learning to evaluate the information content of tropospheric trace gas columns for fine particle estimates over India: a modeling testbed
Published: 2022-03-21
Subjects: Artificial Intelligence and Robotics, Atmospheric Sciences, Civil and Environmental Engineering, Computer Sciences, Earth Sciences, Environmental Engineering, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
India is largely devoid of high-quality and reliable on-the-ground measurements of fine particulate matter (PM2.5). Ground-level PM2.5 concentrations are estimated from publicly available satellite Aerosol Optical Depth (AOD) products combined with other information. Prior research has largely overlooked the possibility of gaining additional accuracy and insights into the sources of PM using [...]
Interannual variability of the Australian summer monsoon sustained through internal processes: wind-evaporation feedback, dynamical air-sea interaction and soil moisture memory
Published: 2022-02-25
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology
In northern Australia (NAUS), mean rainfall during the Australian summer monsoon (AUSM) season exhibits distinct interannual variability despite weak influence from tropical sea surface temperature (SST) variability. The present study investigates mechanisms for the strong and persistent rainfall anomalies throughout the AUSM season. When the AUSM is stronger than normal, the low-level monsoonal [...]
Numerical simulation of atmospheric Lamb waves generated by the 2022 Hunga-Tonga volcanic eruption
Published: 2022-02-09
Subjects: Oceanography and Atmospheric Sciences and Meteorology
On January 15th, 2022, around 4:30 UTC the eruption of the Hunga-Tonga volcano, in the South Pacific Ocean, generated a violent underwater explosion. In addition to tsunami waves that affected the Pacific coasts, the eruption created atmospheric pressure disturbances that spread out in the form of Lamb waves. The associated atmospheric pressure oscillations were detected in high-frequency in-situ [...]
Forecasting Marine Heatwaves using Machine Learning
Published: 2022-02-05
Subjects: Computer Sciences, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology
Recently, severe warm-water episodes have occurred frequently against a background trend of global ocean warming. Sea Surface Temperature anomalies have an impact on the integrity of marine ecosystems which is an important part of the Earth’s climate system. The drastic effects of Marine Heatwaves on aquatic life have been on a steady incline in the recent years, damaging aquatic ecosystems [...]
Meteotsunamis in Japan associated with the Tonga Eruption in January 2022
Published: 2022-02-03
Subjects: Oceanography and Atmospheric Sciences and Meteorology
Large-amplitude meteotsunamis were observed in many areas in Japan, following the arrival of barometric Lamb waves emitted by an underwater volcanic eruption of Hunga Tonga-Hunga Ha‘apai in January 2022. We modeled the power spectra of the tidal level data obtained from 12 tide stations of the Geospatial Information Authority of Japan, based on a single transfer function which converts the [...]
Meteotsunami observed in Japan following the Hunga Tonga eruption in 2022 investigated using a one-dimensional shallow-water model
Published: 2022-01-29
Subjects: Oceanography and Atmospheric Sciences and Meteorology
On January 15, 2022, the volcano Hunga Tonga about 8000-km away from Japan explosively erupted. Following the eruption, tsunami-like sea-level fluctuations were observed in Japan, much earlier than expected based on the oceanic long-wave propagation from Tonga. By contrast, atmospheric pressure disturbance presumably due to the eruption was also observed about 30 minutes before the sea-level [...]
Vertically Resolved Convective/Stratiform Echo Type Identification and Convectivity Retrieval for Vertically Pointing Radars
Published: 2022-01-28
Subjects: Atmospheric Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology
Using data from the airborne HIAPER Cloud Radar (HCR), a partitioning algorithm (ECCO-V) that provides vertically resolved convectivity and convective vs stratiform radar echo classification is developed for vertically pointing radars. The algorithm is based on the calculation of reflectivity and radial velocity texture fields that measure the horizontal homogeneity of cloud and precipitation [...]
3D Convective/Stratiform Echo Type Classification and Convectivity Retrieval from Radar Reflectivity
Published: 2022-01-27
Subjects: Oceanography and Atmospheric Sciences and Meteorology
The newly developed ECCO (Echo Classification from COnvectivity) algorithm identifies convective and stratiform types of radar echo in three dimensions. It is based on the calculation of reflectivity texture - a measure of the heterogeneity of the radar echoes on each horizontal plane in a 3D Cartesian volume. Reflectivity texture is translated into convectivity, which is a newly invented [...]
Deep submarine infiltration of altered geothermal groundwater on the south Chilean Margin
Published: 2022-01-25
Subjects: Earth Sciences, Geochemistry, Geology, Hydrology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Physical Sciences and Mathematics
Submarine groundwater discharge is increasingly recognized as an important component of the oceanic geochemical budget, but knowledge of the distribution of this phenomenon is limited. To date, reports of meteoric inputs to marine sediments are typically limited to shallow shelf and coastal environments, whereas contributions of freshwater along deeper sections of tectonically active margins like [...]
Evaluation of changes in dry and wet precipitation extremes in warmer climates using a passive water vapor modelling approach
Published: 2022-01-22
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology
Hydroclimatic extremes, such as heavy daily rainfall and dry spells, are expected to intensify under anthropogenic warming. Often, these changes are diagnostically related to thermodynamic increases in humidity with warming. Here, we develop a framework that uses an on-line calculation of the thermodynamically induced changes of the full precipitation distribution with warming in an idealized [...]
Diapycnal Displacement, Diffusion, and Distortion of Tracers in the Ocean
Published: 2022-01-08
Subjects: Applied Mathematics, Fluid Dynamics, Non-linear Dynamics, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Small-scale mixing drives the diabatic upwelling that closes the abyssal ocean overturning circulation. Indirect microstructure measurements of in situ turbulence suggest that mixing is bottom enhanced over rough topography, implying downwelling in the interior and stronger upwelling in a sloping bottom boundary layer. Tracer release experiments (TREs), in which inert tracers are purposefully [...]
Dynamics of Eddying Abyssal Mixing Layers over Sloping Rough Topography
Published: 2022-01-08
Subjects: Applied Mathematics, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The abyssal overturning circulation is thought to be primarily driven by small-scale turbulent mixing. Diagnosed water-mass transformations are dominated by rough topography “hotspots,” where the bottom enhancement of mixing causes the diffusive buoyancy flux to diverge, driving widespread downwelling in the interior—only to be overwhelmed by an even stronger upwelling in a thin bottom boundary [...]