Preprints
Filtering by Subject: Atmospheric Sciences
Seasonal Rainfall Forecasts for the Yangtze River Basin in the Extreme Summer of 2020
Published: 2021-02-28
Subjects: Atmospheric Sciences, Climate, Meteorology
Seasonal forecasts for Yangtze River basin rainfall in June, May–June–July (MJJ) and June–July–August (JJA) 2020 are presented, following successful forecasts in previous years. The 3-month forecasts are based on dynamical predictions of an East Asian Summer Monsoon (EASM) index, which is transformed into regional-mean rainfall through linear regression. The June rainfall forecasts for the [...]
The 3D Structure of Northern Hemisphere Blocking Events: Climatology, Role of Moisture, and Response to Climate Change
Published: 2021-02-16
Subjects: Atmospheric Sciences, Climate
We present a comprehensive composite analysis of the 3D structure of blocks and its response to future climate change over North Pacific, North Atlantic, and Russia in summers and winters. Using reanalysis and two large-ensemble datasets from CESM1 and GFDL-CM3, we investigate the following: The climatology of 3D structure, physical processes governing the temperature anomaly associated with [...]
Reduced High-Latitude Land Seasonality in Climates with Very High Carbon Dioxide
Published: 2021-02-10
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology
Observations of warm past climates and projections of future climate change show that the Arctic warms more than the global mean, particularly during winter months. Past warm climates such as the early Eocene had above-freezing Arctic continental temperatures year-round. In this paper, we show that a reduced Arctic land seasonality with increased greenhouse gases is a robust consequence of the [...]
A study of nowcast of Indian Monsoon Rainfall over Mumbai using Rainymotion
Published: 2020-12-31
Subjects: Atmospheric Sciences, Meteorology, Numerical Analysis and Scientific Computing
Since ages, we know that rainfall is a very important factor in deciding the fate of a country. In an agrarian country like India where more than 70% of rural households are dependent on agriculture, agriculture contributes to nearly 17% GDP of the country and is directly dependent on rainfall. Excessive rainfall can lead to floods, landslides, soil erosion and no rainfall can lead to [...]
Global air quality change during COVID-19: a synthetic result of human activities and meteorology
Published: 2020-12-19
Subjects: Atmospheric Sciences
In recent months, coronavirus disease 2019 (COVID-19) has been spreading around the globe, and this has led to a rare reduction in human activities. In such a background, data from ground-based environmental stations, satellites, and reanalysis materials are utilized to conduct a comprehensive analysis of the air quality changes during the COVID-19 outbreak at the global scale. The results showed [...]
The influence of orbital parameters on the North American Monsoon system during the Last Interglacial Period
Published: 2020-12-17
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Environmental Sciences, Hydrology, Oceanography and Atmospheric Sciences and Meteorology
The response of summer precipitation in the western U.S. to climate variability remains a subject of uncertainty. For example, paleoclimate records indicate the North American monsoon (NAM) was stronger and spatially more extensive during the Holocene, whereas recent modeling suggests a weakened NAM response to increasing temperatures. These illustrate diverging pictures of the NAM response to [...]
Bias correction of global climate model using machine learning algorithms to determine meteorological variables in different tropical climates of Indonesia
Published: 2020-12-11
Subjects: Applied Statistics, Atmospheric Sciences, Planetary Geophysics and Seismology, Statistical Models
Accurate and localized forecasting of climate variables are important especially in the face of uncertainty imposed by climate change. However, the data used for prediction are either incomplete at the local level or inaccurate because the simulation models do not explicitly consider local contexts and extreme events. This paper, therefore, attempts to bridge this gap by applying tree-based [...]
The Emergent Influence of Anthropogenic Warming on Global Crop Yields
Published: 2020-10-30
Subjects: Atmospheric Sciences, Climate, Environmental Sciences, Social and Behavioral Sciences, Statistical Methodology
A large literature on “detection and attribution” has now demonstrated the influence of anthropogenic greenhouse gas emissions on a range of physical climate variables. Social and economic outcomes are known to be sensitive to climate change, but directly connecting observed changes to anthropogenic forcing is challenging. Here I estimate the effect of anthropogenic warming on global crop yield [...]
Urban Air Quality Modeling Using Low-Cost Sensor Network and Data Assimilation in the Aburra Valley, Colombia
Published: 2020-10-30
Subjects: Applied Mathematics, Atmospheric Sciences, Environmental Monitoring
The use of low air quality networks has been increasing in recent years to study urban pollution dynamics. Here we show the evaluation of the operational Aburra Valley's low-cost network against the official monitoring network. The results show that the PM2.5 low-cost measurements are very close to those observed by the official network. Additionally, the low-cost allows a higher spatial [...]
The Global Warming Potential Misrepresents the Physics of Global Warming Thereby Misleading Policy Makers
Published: 2020-10-25
Subjects: Atmospheric Sciences, Environmental Sciences, Oil, Gas, and Energy
The Global Warming Potential (GWP) is a widely used metric used to compare the climate change effects of various greenhouse gases. Although GWP has an established role in international climate agreements, GWP does not, in general, describe any specific identifiable impact of greenhouse gas emissions on climate. It is argued here that GWP is unphysical, unintuitive, arbitrary, ignores the time [...]
Correcting 19th and 20th century sea surface temperatures improves simulations of Atlantic hurricane activity
Published: 2020-08-21
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 [...]
An Eddy-Zonal Flow Feedback Model for Propagating Annular Modes
Published: 2020-07-21
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. [...]
Mass independent fractionation of even and odd mercury isotopes during atmospheric mercury redox reactions
Published: 2020-07-08
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Mass independent fractionation (MIF) of even mass number mercury (Hg) stable isotopes is observed in rainfall and gaseous elemental Hg0 globally, and is used to quantify atmospheric Hg deposition pathways. The chemical reaction and underlying even-Hg MIF mechanism are unknown however, and speculated to be caused by Hg photo-oxidation on aerosols at the tropopause. Here we investigate the Hg [...]
Surprising Changes in Aerosol Loading over India Amid COVID-19 Lockdown
Published: 2020-07-06
Subjects: Atmospheric Sciences, Climate, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Using ground-based and satellite observation along with aerosol reanalysis products, we show a widespread reduction in aerosol loading over the Indian subcontinent during the COVID-19 (COronaVIrus Disease 2019) lockdown. The pre-lockdown and lockdown period considered in the present study is 20th February–20th March 2020 and 24th March–22nd April 2020. In terms of aerosol optical depth (AOD), [...]