Preprints
Filtering by Subject: Oceanography and Atmospheric Sciences and Meteorology
Enhanced hydrological cycle increases ocean heat uptake and moderates transient climate sensitivity
Published: 2020-11-25
Subjects: Climate, Oceanography, Oceanography and Atmospheric Sciences and Meteorology
The large-scale moistening of the atmosphere in response to increasing greenhouse gases amplifies the existing patterns of precipitation minus evaporation (P-E) which, in turn, amplifies the spatial contrast in sea surface salinity (SSS). Through a series of CO2 doubling experiments, we demonstrate that surface salinification driven by the amplified dry conditions (P-E < 0), primarily in the [...]
Investigation on the Impacts of COVID-19 Lockdown and Influence Factors on Air Quality in Greater Bangkok, Thailand
Published: 2020-11-06
Subjects: Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
With the outbreak of the COVID-19 pandemic around the world, many countries announced lockdown measures, including Thailand. Several scientific studies have reported on improvements in air quality due to the impact of these COVID-19 lockdowns. This study aims to investigate the effects of the COVID-19 lockdown and its driving influence factors on air pollution in Greater Bangkok, Thailand using [...]
IBM PAIRS: Scalable big geospatial-temporal data and analytics as-a-service
Published: 2020-11-02
Subjects: Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
The rapid growth of geospatial-temporal data from sources like satellites, drones, weather modeling, IoT sensors etc., accumulating at a pace of PetaBytes to ExaBytes annually, opens unprecedented opportunities for both science and industrial applications. However, the sheer size and complexity of such data presents significant challenges for conventional geospatial information systems (GIS) [...]
Global decline of deep water formation with increasing atmospheric CO2
Published: 2020-10-24
Subjects: Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
Deep water formation is not only the driver of the global ocean circulation; by sending heat and carbon to the deep ocean, it is also crucial for climate change mitigation. Yet its future is uncertain: will it slow down as stratification increases, emerge in polar regions as the wind starts blowing over previously ice-covered waters, or intensify with increased evaporation? Here we present the [...]
A data assimilation approach to last millennium temperature field reconstruction using a limited high-sensitivity proxy network
Published: 2020-10-23
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Paleoclimate field reconstructions using data assimilation commonly employ large proxy networks, which are often composed of records that have a complex range of sensitivities to the target climate field. This can introduce biases into reconstructions or decrease overall skill. Smaller networks of highly-sensitive proxies provide an alternative, but have not been extensively used for assimilation [...]
Dynamical analysis of a reduced model for the North Atlantic Oscillation
Published: 2020-10-21
Subjects: Applied Mathematics, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The dynamics of the North Atlantic Oscillation (NAO) are analyzed through a data-driven model obtained from atmospheric reanalysis data. We apply a regularized vector autoregressive clustering technique to identify recurrent and persistent states of atmospheric circulation patterns in the North Atlantic sector (110W-0E, 20N-90N). In order to analyze the dynamics associated with the resulting [...]
Grain Size and Beach Face Slope on Paraglacial Beaches of New England, USA
Published: 2020-10-21
Subjects: Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
Approximately 100 paired summer and winter transects of beach face slope and intertidal grain size were examined from 18 separate beaches in southern New England that span meso- and micro- tidal regimes. Paraglacial materials provide the principal local sediment source to beaches in this region and grain-size distribution of beaches corresponds to adjacent surficial geology. Stratified glacial [...]
Mercury stable isotopes constrain atmospheric sources to the Ocean
Published: 2020-08-28
Subjects: Earth Sciences, Environmental Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Human exposure to toxic mercury (Hg) is dominated by the consumption of seafood1,2. Earth system models suggest that Hg in marine ecosystems is supplied by atmospheric wet and dry Hg(II) deposition, with a 3 times smaller contribution from gaseous Hg(0) uptake3,4. Observations of marine Hg(II) deposition and Hg(0) gas exchange are sparse however5, leaving the suggested importance of Hg(II) [...]
Identifying and correcting the World War 2 warm anomaly in sea surface temperature measurements
Published: 2020-08-20
Subjects: Climate, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Most foregoing estimates of historical sea surface temperature (SST) feature warmer global-average SSTs during World War 2 well in excess of climate-model predictions. This warm anomaly, referred to as the WW2WA, was hypothesized to arise from incomplete corrections of biases associated with rapid changes in measurement instruments and protocols. Using linear mixed-effects methods we confirm [...]
Correcting 19th and 20th century sea surface temperatures improves simulations of Atlantic hurricane activity
Published: 2020-08-20
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Changes in the statistics of North Atlantic hurricanes are known to depend upon the pattern of tropical sea surface temperatures (SSTs). Dynamical and statistical models are key tools to predict future hurricane activity, with our confidence in this application rooted in the models’ ability to skillfully reproduce hurricane variations over the past 30-40 years, when satellite data allows [...]
A Statistical Evaluation of WRF-LES Trace Gas Dispersion Using Project Prairie Grass Measurements
Published: 2020-08-17
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
In recent years, new measurement systems have been deployed to monitor and quantify methane emissions from the natural gas sector. Large-eddy simulation (LES) has complemented measurement campaigns by serving as a controlled environment in which to study plume dynamics and sampling strategies. However, with few comparisons to controlled-release experiments, the accuracy of LES for modeling [...]
Changes in temperature and rainfall extremes across East Asia in the CMIP5 ensemble
Published: 2020-07-21
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
We analyze annual extremes of daily maximum and minimum surface air temperature and of daily rainfall in East Asia and the Korean peninsula. This study made intensive use of the simulation data available from the CMIP5 (Coupled Model intercomparison Project Phase 5) multimodels in historical and future experiments up to year 2100, employing three different radiative forcings: RCP2.6, RCP4.5, [...]
A general expression for wave-induced sediment bypassing of an isolated headland
Published: 2020-07-20
Subjects: Earth Sciences, Engineering, Geomorphology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Engineering, Physical Sciences and Mathematics
Accurate knowledge of the sediment budget of a coastal cell is necessary for coastal management and predicting long-term coastal change. An important component in the sediment budget of many wave-dominated embayed coastlines is the amount of sediment that bypasses rocky headlands, which present partial barriers to alongshore transport. Despite a recent surge in research interest in headland [...]
An Eddy-Zonal Flow Feedback Model for Propagating Annular Modes
Published: 2020-07-20
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The variability of the zonal-mean large-scale extratropical circulation is often studied using individual modes obtained from empirical orthogonal function (EOF) analyses. The prevailing reduced-order model of the leading EOF (EOF1) of zonal-mean zonal wind, called the annular mode, consists of an eddy-mean flow interaction mechanism that results in a positive feedback of EOF1 onto itself. [...]
Modelling an energetic tidal strait: investigating implications of common numerical configuration choices
Published: 2020-07-16
Subjects: Applied Mathematics, Civil and Environmental Engineering, Civil Engineering, Engineering, Numerical Analysis and Computation, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Characterising tidal hydrodynamics in the vicinity of submerged features can be demanding given the hostility of the marine environment. Logistical challenges in the measurement of such flows has promoted research on wake studies through physical and numerical modelling. In this study, site measurements and modelled data are combined to provide an insight into the regional hydrodynamics within a [...]