A5056213449- Meteorological Phenomena and Simulations
- Atmospheric Ozone and Climate
- Atmospheric chemistry and aerosols
- Climate variability and models
- Ionosphere and magnetosphere dynamics
- Atmospheric aerosols and clouds
- Atmospheric and Environmental Gas Dynamics
- Geophysics and Gravity Measurements
- Ocean Acidification Effects and Responses
- Solar and Space Plasma Dynamics
- Spaceflight effects on biology
- Oceanographic and Atmospheric Processes
- Mechanical stress and fatigue analysis
- Electrical Contact Performance and Analysis
- Advanced Numerical Methods in Computational Mathematics
- Advanced Aircraft Design and Technologies
- Calibration and Measurement Techniques
- Ocean Waves and Remote Sensing
- Thermal Analysis in Power Transmission
- Geophysics and Sensor Technology
- Air Traffic Management and Optimization
- Model Reduction and Neural Networks
- Vehicle emissions and performance
- Nitric Oxide and Endothelin Effects
NSF National Center for Atmospheric Research
2007-2020
Bjerknes Centre for Climate Research
2019
This paper describes climate simulations of the Community Atmosphere Model, version 5 (CAM5), coupled with a higher-order turbulence closure known as Cloud Layers Unified by Binormals (CLUBB). CLUBB is unified parameterization planetary boundary layer (PBL) and shallow convection that centered around trivariate probability density function (PDF) replaces conventional PBL, convection, cloud macrophysics schemes in CAM5. CAM–CLUBB improves many aspects base state compared to Chief among them...
High Resolution Dynamics Limb Sounder (HIRDLS) temperature profiles are analyzed to derive global properties of gravity waves. We describe a wavelet analysis technique that determines covarying wave amplitude in adjacent profile pairs, the vertical wavelength as function height, and horizontal number along line joining each pair. The allows local estimate magnitude momentum flux geographic location height on daily basis. examine distributions these monthly mean an individual day, we also...
Abstract. This paper documents coupled simulations of two developmental versions the Community Atmosphere Model (CAM) towards CAM6. The configuration called CAM5.4 introduces new microphysics, aerosol, and ice nucleation changes, among others to CAM. CAM5.5 represents a more radical departure, as it uses an assumed probability density function (PDF)-based unified cloud parameterization replace turbulence, shallow convection, warm macrophysics in PDF method has been widely used last decade...
The High Resolution Dynamics Limb Sounder (HIRDLS) experiment was designed to provide global temperature and composition data on the region from upper troposphere mesopause with vertical horizontal resolution not previously available. science objectives are study of small‐scale dynamics transports, including stratosphere‐troposphere exchange, troposphere/lower stratosphere chemistry, aerosol, cirrus PSC distributions, gravity waves. instrument features 21 channels, low noise levels, high...
Abstract. This paper describes the coupling of Community Atmosphere Model (CAM) version 5 with a unified multi-variate probability density function (PDF) parameterization, Cloud Layers Unified by Binormals (CLUBB). CLUBB replaces planetary boundary layer (PBL), shallow convection, and cloud macrophysics schemes in CAM5 higher-order turbulence closure based on an assumed PDF. Comparisons single-column versions CAM-CLUBB are provided this for several regimes. As compared to large eddy...
High Resolution Dynamics Limb Sounder (HIRDLS) and Cloud‐Aerosol Lidar Infrared Pathfinder Satellite Observation (CALIPSO) measurements of cirrus frequency occurrence in the upper tropical troposphere are quantified for September 2006 to August 2007. Monthly geospatial averages cloud between 90 177 hPa similar correlate well with Microwave (MLS) relative humidity respect ice (RHI) data, though clouds present at individual RHI values less than 100%, due 5, 1, sub‐1 km vertical resolutions...
Abstract. Most global climate models parameterize separate cloud types using parameterizations. This approach has several disadvantages, including obscure interactions between parameterizations and inaccurate triggering of cumulus Alternatively, a unified parameterization uses one equation set to represent all types. Such include stratiform liquid ice cloud, shallow convective deep cloud. Vital the success is general interface clouds microphysics. One such involves drawing Monte Carlo...
This paper documents the incorporation of an inventory AEDT (Aviation Environmental Design Tool) global commercial aircraft emissions for year 2006 into National Center Atmospheric Research Community Earth System Model (CESM) version 1. The original dataset reports emission mass ten species on hourly basis which is converted to monthly mixing ratio tendencies as released dataset. We also describe how incorporated CESM. A contrail parameterization implemented in CESM it assumed that...
Comparisons of the latest High Resolution Dynamics Limb Sounder (HIRDLS) ozone retrievals (v2.04.09) are made with ozonesondes, ground‐based lidars, airborne lidar measurements during Intercontinental Chemical Transport Experiment–B, and satellite observations. A large visual obstruction blocking over 80% HIRDLS field view presents significant challenges to data analysis methods implementation, extent that radiative properties must be accurately characterized in order adequately correct...
The retrieval algorithm for the High Resolution Dynamics Limb Sounder (HIRDLS) instrument onboard NASA's Earth Observing System (EOS) Aura satellite is presented. based on optimal estimation theory, using a modified Levenberg‐Marquardt approach iterative solution. Overview of scheme, convergence criteria, and forward models given. Treatments clouds aerosols as well line‐of‐sight gradients in temperature are described. retrievals characterized by high vertical resolution 1 km negligible...
Validation studies of multiwavelength Cryogenic Limb Array Etalon Spectrometer (CLAES) observations stratospheric aerosol are discussed. An error analysis the CLAES extinction data is presented. Aerosol precision values estimated at latitudes and times which consecutive Upper Atmosphere Research Satellite (UARS) orbits overlap. Comparisons with theoretical Mie calculations, based upon in situ particle size measurements Laramie, Wyoming, also compared to scaled measured by Stratospheric Gas...
The High Resolution Dynamics Limb Sounder (HIRDLS) cloud detection and top determination algorithm is described applied to 2005–2007 HIRDLS radiance profiles. Statistical averages of correlative data are highly correlated. 1998–2005 Halogen Occultation Experiment (HALOE) time averaged pressures have a correlation coefficient 0.87 0.93 in the tropics midlatitudes, respectively. Time series temperature T < 195 K hemispherical area, on 450 potential surface, total number polar stratospheric...
Simulations by climate models are used to project the change expected as atmospheric greenhouse gas concentrations rise. How much will Earth warm? Will south Asia experience stronger monsoons in future? American Southwest continue desiccate? soon Arctic become ice free? fast and how sea level rise? Climate rely on idea that sound physical principles can be translate basic information, such emissions of carbon dioxide aerosols, into changes energy balance influence formation clouds, which...
We present the first evaluation of HNO 3 data product (version 2.04.09) from High Resolution Dynamics Limb Sounder (HIRDLS) on Earth Observing System (EOS) Aura satellite. The HIRDLS instrument obtains between 5000 and 7000 profiles per day. are generally good over latitude range 64°S to 80°N pressure 100 10 hPa, with some profiles, depending latitude, having useful information 161 hPa. individual profile “measured” precision is 15%, but can be much larger if abundance low or outside hPa...
Abstract. Numerical general circulation models of the atmosphere are generally required to conserve mass and energy for their application climate studies. Here we draw attention another conserved global integral, viz. component angular momentum (AM) along Earth's axis rotation, which tends receive less consideration. We demonstrate importance AM conservation in simulations with example Community Atmosphere Model (CAM) finite-volume (FV) dynamical core, produces a noticeable numerical sink...
Abstract. Most global climate models parameterize separate cloud types using parameterizations. This approach has several disadvantages, including obscure interactions between parameterizations and inaccurate triggering of cumulus Alternatively, a unified parameterization uses one equation set to represent all types. Such include stratiform liquid ice cloud, shallow convective deep cloud. Vital the success is general interface clouds microphysics. One such involves drawing Monte Carlo...
The High Resolution Dynamics Limb Sounder (HIRDLS) instrument was launched on NASA's Aura spacecraft 15 July 2004. When activation completed 25 days later, it discovered that the measured radiances were very different from those expected. After a long series of analyses and diagnostic tests, cause confirmed to be blockage covers much front aperture, preventing even one completely clear view atmosphere. In this paper steps required correct for effects are noted. These calibrating radiances,...
Abstract. This paper describes the coupling of Community Atmosphere Model (CAM) version 5 with a unified multi-variate probability density function (PDF) parameterization, Cloud Layers Unified by Binormals (CLUBB). CLUBB replaces planetary boundary layer (PBL), shallow convection, and cloud macrophysics schemes in CAM5 higher-order turbulence closure based on an assumed PDF. Comparisons single-column versions CAM-CLUBB are provided this for several regimes. As compared to Large Eddy...
Abstract. We present a numerical method to enforce global conservation of atmospheric axial angular momentum (AM) in the Community Atmosphere Model (CAM). discuss results hierarchy simulations atmosphere increasing complexity, and we demonstrate importance AM climate simulations.
The paper gives brief details of the conductor-rail systems used for electric traction by London Transport Executive1 and British Railways.The specification, testing, installation maintenance 100- 150-lb/yd flat-bottom conductor rails on Southern Region's 660-volt d.c. third-rail system which conforms to Railway (Standardization Electrification) Order, 1932, are described in detail. associated electrical track equipment is reviewed.Details given proposed new standard 106- 130-lb/yd...