Preprints
Filtering by Subject: Atmospheric Sciences
Observation-based Simulations of Humidity and Temperature Using Quantile Regression
Published: 2020-05-28
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Statistics and Probability
The human impacts of changes in heat events depend on changes in the joint behavior of temperature and humidity. Little is currently known about these complex joint changes, either in observations or projections from general circulation models (GCMs). Further, GCMs do not fully reproduce the observed joint distribution, implying a need for simulation methods that combine information from GCMs [...]
UNSEEN trends: Detecting decadal changes in 100-year precipitation extremes
Published: 2020-05-25
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Climate, Earth Sciences, Engineering, Environmental Sciences, Hydrology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Sample sizes of observed climate extremes are typically too small to reliably constrain non-stationary behaviour. To facilitate detection of non-stationarities in 100-year precipitation values over a short period of 35 years (1981-2015), we apply the UNprecedented Simulated Extreme ENsemble (UNSEEN) approach, by pooling ensemble members and lead times from the ECMWF seasonal prediction system [...]
Human Health Benefits of the Minamata Convention on Mercury
Published: 2020-05-17
Subjects: Atmospheric Sciences, Biogeochemistry, Climate, Earth Sciences, Environmental Health and Protection, Environmental Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The Minamata Convention is a legally-binding international treaty aimed at reducing the anthropogenic release of mercury, a potent neurotoxin. However, its human health benefit has not been quantified on a global scale. Here we evaluate the Convention’s benefit by a coupled climate-atmosphere-land-ocean-ecosystem model and a human mercury exposure component that considers all food categories. We [...]
A machine learning approach for ozone forecasting and its application for Kennewick, WA
Published: 2020-05-13
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Chemical transport models (CTM) are widely used for air quality modeling, but these models miss forecasting some air pollution events, and require a lot of computational power. In Kennewick, WA, elevated O3 episodes can occur during the summer and early fall, but the CTM-based operational forecasting system (AIRPACT) struggles to capture them. This research used the 2015 – 2018 historical [...]
COVID-19-related drop in anthropogenic aerosol emissions in China and corresponding cloud and climate effects
Published: 2020-05-11
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Environmental Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The COVID-19 pandemic has led to massive disruptions of public life on a global scale. To halt the spread of the disease, China temporarily shut down parts of the manufacturing and transportation sectors. Associated anthropogenic aerosol emissions in February 2020 plunged to record lows, causing a temporary improvement of air quality with uncertain effects on cloud formation, atmospheric [...]
Asian monsoon amplifies semi-direct effect of biomass burning aerosols on low cloud formation
Published: 2020-05-11
Subjects: Atmospheric Sciences, Climate, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Low clouds play a key role in the Earth-atmosphere energy balance and influence agricultural production and solar-power generation. Smoke aloft has been found to enhance marine stratocu-mulus over the Southeast Atlantic in austral spring through aerosol-cloud interactions, but its role in regions with strong human activities and complex monsoon circulation remains unclear. Here we show that [...]
Macroscopic flow disequilibrium over aeolian dune fields
Published: 2020-05-08
Subjects: Atmospheric Sciences, Earth Sciences, Geomorphology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Sedimentology
Aeolian dune fields are self-organized patterns formed by wind-blown sand. Dunes are topographic roughness elements that impose drag on the atmospheric boundary layer (ABL), creating a natural coupling between form and flow. While the steady-state influence of drag on the ABL is well studied, non-equilibrium effects due to roughness transitions are less understood. Here we examine the large-scale [...]
Aerosols bias daily weather prediction
Published: 2020-05-07
Subjects: Atmospheric Sciences, Climate, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Weather prediction is essential to human daily life. Current numerical weather prediction (NWP) models are still subject to substantial forecast bias and rarely consider the impact of atmospheric aerosols, despite of the consensus of aerosols as the most important sources of uncertainty in predicting climate change. Here we show aerosols as an important driver biasing daily temperature [...]
Estimating Submicron Aerosol Mixing State at the Global Scale with Machine Learning and Earth System Modeling
Published: 2020-05-06
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Computational Engineering, Computer Sciences, Earth Sciences, Engineering, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
This study integrates machine learning and particle-resolved aerosol simulations to develop emulators that predict sub-micron aerosol mixing state indices from the Earth System Model (ESM) simulations. The emulators predict aerosol mixing state using only ESM bulk aerosol species concentrations, which do not by themselves carry mixing state information. Here we used PartMC as the [...]
Predicting outbreak-level tornado counts and casualties from environmental variables
Published: 2020-04-29
Subjects: Atmospheric Sciences, Earth Sciences, Life Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Environmental variables are used routinely in forecasting when and where an outbreak of tornadoes are likely to occur, but more work is needed to understand how characteristics of severe weather outbreaks vary with the larger scale environmental factors. Here the authors demonstrate a method to quantify `outbreak-level tornado and casualty counts with respect to variations in large-scale [...]
Large-eddy simulation of traffic-related air pollution at a very high-resolution in a mega-city: Evaluation against mobile sensors and insights for influencing factors
Published: 2020-04-29
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Urban air pollution has tremendous spatial variability at scales ranged from kilometer to meters due to unevenly distributed emission sources, complex flow patterns, and photochemical reactions. However, high-resolution air quality information is not available through traditional approaches such as ground-based measurements and regional air quality models (with typical resolution >1 km). Here [...]
Spontaneous Cyclogenesis without Radiative and Surface-Flux Feedbacks
Published: 2020-04-18
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Tropical cyclones (TCs) are among the most intense and feared storms in the world. What physical processes lead to cyclogenesis remains the most mysterious aspect of TC physics. Here, we study spontaneous TC genesis in rotating radiative-convective equilibrium using cloud-resolving simulations over an f-plane with constant sea-surface temperature. Previous studies proposed that spontaneous TC [...]
Do atmospheric plastics act as fomites for novel viruses?
Published: 2020-04-15
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Engineering, Environmental Health and Protection, Environmental Sciences, Life Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Plastic particles are ubiquitous in various environmental compartments, the atmosphere being the least explored compartment in terms of plastic pollution. The way that atmospheric plastics affect the biological systems has not yet been explored when compared to aquatic ecosystems. There are many speculated human health impacts, one definite and direct impact of atmospheric plastics would be [...]
Enhanced secondary pollution offset reduction of primary emissions during COVID-19 lockdown in China
Published: 2020-04-13
Subjects: Atmospheric Sciences, Environmental Health and Protection, Environmental Monitoring, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
To control the spread of the 2019 novel coronavirus (COVID-19), China imposed nationwide restrictions on the movement of its population (lockdown) after the Chinese New Year of 2020, leading to large reductions in economic activities and associated emissions. Despite such large decreases in primary pollution, there were nonetheless several periods of heavy haze pollution in East China, raising [...]
Seasonal Rainfall Forecasts for the Yangtze River Basin in Summer 2019 from an Improved Climate Service
Published: 2020-03-18
Subjects: Atmospheric Sciences, Climate, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Rainfall forecasts for the summer monsoon season in the Yangtze River Basin allow decision-makers to plan for possible flooding, which can affect the lives and livelihoods of millions of people. A trial climate service was developed in 2016, producing a prototype seasonal forecast product for use by stakeholders in the region, based on forecasting rainfall directly using a dynamical model. Here [...]