Browsing Atmospheric sciences by Title
Now showing items 92-111 of 301
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Heterogeneous nitrate production mechanisms in intense haze events
The importance of heterogeneous (multi-phase) reactions between trace gases and particulates in controlling the tropospheric chemistry of reactive nitrogen oxides and driving the production of nitrate has long been recognized. ... -
High-drag states and lee vortices in stratified flow over topography
(1999)Stratified flow with uniform basic wind and stability past long three-dimensional (3d) ridges is studied in the absence of surface friction and planetary rotation. The dominant control parameters for this problem are the ... -
Higher Order Trapped Lee Waves in the Stratosphere
Wave activity with maximum amplitude in the stratosphere downstream of major mountain ranges has previously been explained as a result of wave breaking inducing secondary wave generation in the stratosphere (Vadas et al., ... -
Hurricane kinetic energy spectra from in situ aircraft observations
Just over 30 years ago, Nastrom and Gage (1985) completed their seminal paper on aircraft-derived power spectra. Since then, significant strides have been made in understanding the wavenumber distribution of energy in ... -
Ice-atmosphere interactions and sea ice predictability at multiple resolutions in the Community Earth System Model
This work introduces a high resolution (0.1° ocean), slab ocean version of the Community Earth System Model (CESM1(CAM5)). This model is used to investigate ice/atmosphere interactions through comparison with a standard ... -
Idealized Numerical Modeling Experiments of the Diurnal Cycle of Tropical Cyclones
Numerical experiments are performed to evaluate the role of the daily cycle of radiation on axisymmetric hurricane structure. Although a diurnal response in the high cloudiness of tropical cyclones (TCs) has been well ... -
Identifying Meteorological Controls on Open and Closed Mesoscale Cellular Convection Associated with Marine Cold Air Outbreaks
Mesoscale cellular convective (MCC) clouds occur in large-scale patterns over the ocean and have important radiative effects on the climate system. An examination of time-varying meteorological conditions associated with ... -
Impact of changing Arctic sea ice extent, sea ice age, and snow depth on sea salt aerosol from blowing snow and the open ocean for 1980-2017
The Arctic is undergoing rapid change: temperature is rising at double the rate as the global average, sea ice extent is declining, the age of sea ice is becoming younger, and snow depth on sea ice is thinning. The effect ... -
Impact of Stratospheric Intrusions, Regional Wildfires, and Long-Range Transport Events on Air Quality in the Western United States
Baseline ozone refers to observed concentrations of tropospheric ozone at sites that have a negligible influence from local emissions. In 2004, the Mount Bachelor Observatory (MBO) was established to examine baseline air ... -
Impacts of Biomass Burning on Ozone, Particulate Matter, and Carbon Dioxide in the Northwest U.S.
Wildfires (or Biomass Burning events) in the northwest U.S. have been increasing in size and frequency throughout the last few decades. This significantly affects vulnerable populations through hazardous fine particulate ... -
Improving boundary layer cloudiness in the NCEP-GFS
(2013-11-14)Substantial biases exist in shortwave cloud radiative forcing in the National Centers for Environmental Prediction Global Forecasting System (GFS), an important global weather forecasting model. An offshoot of this model, ... -
Improving constraints on the sources and distribution of sea salt aerosols in polar regions
Sea salt aerosols (SSA) have a critical influence on radiation, cloud formation and chemistry of the polar atmosphere. In addition to the commonly accepted open ocean source of SSA, several studies have suggested that SSA ... -
Improving Prognostic Moist Turbulence Parameterization with Machine Learning and Software Design
The primary result of this work is that concepts from software design and machine learning may be used to improve moist turbulence parameterization in weather and climate models. We have seen relatively slow improvement ... -
In-situ Observations and Large Eddy Simulations of Southern Ocean Boundary Layer Clouds
Southern Ocean boundary layer clouds affect global albedo and oceanic heat uptake. Most climate models and reanalyses underestimate cloudiness in the Southern Ocean, which biases seas surface temperatures and tropospheric ... -
Influence of Baseline Air Masses and Wildland Fires on Air Quality in the Western United States
Air quality in the western United States (U.S.) is influenced by local and long-distance anthropogenic sources, as well as natural sources such as wildfires and stratospheric intrusions. The U.S. Environmental Protection ... -
The influence of convectively generated thermal forcing on the mesoscale circulation around squall lines
(1996)The dynamical processes that determine the kinematic and thermodynamic structure of the mesoscale region around squall lines are examined using a series of numerical simulations. The features that develop in a realistic ... -
The influence of hemispheric asymmetry and realistic basic states on tropical stationary waves in a shallow water model
(2005)A shallow water model is used to study the stationary waves in the tropical upper troposphere. Realistic zonal-mean winds are generated by imposing a zonally-symmetric topography distribution underneath a thin fluid layer ... -
Influence of meridional constraints and eddy feedbacks on low-frequency variability and its response to climate change
(2012-08-10)Two aspects of the internal variability of the atmosphere are examined. The first concerns the interactions and feedbacks between synoptic-scale Rossby waves (eddies) and the large-scale mean flow. We study the variability ... -
The Influence of Orbital Forcing of Tropical Insolation on the Climate and Isotopic Composition of Precipitation in South America
The δ<super>18</super>O of calcite (δ<super>18</super>O<sub>c</sub>) in speleothems from South America is well correlated with austral summer (DJF) insolation, indicating the role of orbitally paced changes in insolation ... -
The influence of sea ice on Antarctic ice core sulfur chemistry and on the future evolution of Arctic snow depth: Investigations using global models
(2013-02-25)Observational studies have examined the relationship between methanesulfonic acid (MSA) measured in Antarctic ice cores and sea ice extent measured by satellites with the aim of producing a proxy for past sea ice extent. ...