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Full-Text Articles in Atmospheric Sciences

Satellite Measurements Of Mesospheric Gravity Wave Temperature Variance Over The Andes, Jonathan R. Pugmire, Michael J. Taylore, Yucheng Zhao May 2015

Satellite Measurements Of Mesospheric Gravity Wave Temperature Variance Over The Andes, Jonathan R. Pugmire, Michael J. Taylore, Yucheng Zhao

Jonathan Pugmire

Focusing on over 10 years of data from the SABER instrument aboard the TIMED satellite temperature variances are determined to quantify the signatures of short-period gravity waves propagating up into the mesosphere, and lower thermosphere (MLT) region. Temperature profile measurements were measured by SABER within a limited geographical area, centered on the Andes Lidar Observatory at Cerro Pachon, Chile (30.3° S, 70.7° S) where Utah State University has operated an OH Mesospheric Temperature Mapper (MTM) for the past 5 years. Using an established procedure the large-scale tidal waves, with wavenumbers 0-6, were removed from each profile revealing the gravity wave …


Observations Of Mesospheric Gravity Waves Over The Andes, Jonathan Pugmire Apr 2015

Observations Of Mesospheric Gravity Waves Over The Andes, Jonathan Pugmire

Jonathan Pugmire

Focusing on data from an imager and the SABER instrument aboard the TIMED satellite temperature variances are determined to quantify small-scale gravity waves. IDL software was used to extract all the temperature profile measurements that were measured by SABER within a limited geographical area, centered on our ground-based optical imager at Cerro Pachon, Chile (30.3°S, 70.7°S). Large-scale tidal waves, with wavenumbers 0-6, were removed from each profile revealing the gravity wave perturbations. Temperature variances reveal possible increased wave activity due to mountain waves. Mountain waves in the mesosphere are a relatively unexplored field in aeronomy. They are generated predominantly in …


Challenges Associated With Space Weather Analysis And Prediction, John Lanicci Apr 2015

Challenges Associated With Space Weather Analysis And Prediction, John Lanicci

John M Lanicci

The term “space weather” is typically used to describe environmental conditions in the region extending from the sun’s surface, through the interplanetary medium, to the earth’s magnetic field and upper atmosphere, with a focus on those conditions that can affect the earth, its technological systems, and population. Space weather conditions are monitored continuously by a number of agencies around the world. These agencies use both satellite- and ground-based measurements to build analyses and employ predictive models that form the basis for impacts-based products dealing with myriad users in satellite operations, the utility industry, aviation, and satellite-based communications, to name a …


Observations Of Mesospheric Gravity Wave Dynamics In The Southern Hemisphere, Jonathan Pugmire, Michael Taylor Oct 2014

Observations Of Mesospheric Gravity Wave Dynamics In The Southern Hemisphere, Jonathan Pugmire, Michael Taylor

Jonathan Pugmire

Observations of mesospheric OH rotational temperature by the Mesospheric Temperature Mapper located at Cerro Pachon, Chile (30.3°S, 70.7°S) show a large range of variation. Temperature variances reveal increased activity due to mountain waves. Comparative studies with the satellite carried SABER instrument show agreement on nightly, as well as seasonal, temperature measurements. Comparisons with similar temperature measurements from Maui, Hawaii (20.8°N) reveal mountain wave activity to be enhanced over the Andes in the winter months. Initial gravity wave measurements from McMurdo Base, Antarctica are highlighted.


Mesospheric Temperature Variability And Seasonal Characteristics Over The Andes, Jonathan Pugmire, Yucheng Zhao, Michael Taylor, P Pautet Oct 2014

Mesospheric Temperature Variability And Seasonal Characteristics Over The Andes, Jonathan Pugmire, Yucheng Zhao, Michael Taylor, P Pautet

Jonathan Pugmire

The Utah State University CEDAR Mesospheric Temperature Mapper (MTM) is a high-quality CCD imager capable of remote sensing faint optical emissions from the night sky to determine mesospheric temperature and its variability at an altitude of ~87 km. The MTM was operated at the new Andes Lidar Observatory (ALO)located at Cerro Pachon, Chile (30.2° S, 70.7° W) since August 2009 to investigate the seasonal characteristic of the mesopause at mid-latitudes. Measurement were made alongside a powerful lidar capable of height sounding the mesosphere. In this study, the MTM data have been analyzed to determine night to night variability and seasonal …


Steady-State Aerosol Distributions In The Extra-Tropical, Lower Stratosphere And The Processes That Maintain Them, J. Wilson, Shan-Hu Lee, J. Reeves, C. Brock, H. Jonsson, B. Lafleur, M. Loewenstein, J. Podolske, E. Atlas, K. Boering, G. Toon, D. Fahey, T. Bui, G. Diskin, F. Moore Oct 2013

Steady-State Aerosol Distributions In The Extra-Tropical, Lower Stratosphere And The Processes That Maintain Them, J. Wilson, Shan-Hu Lee, J. Reeves, C. Brock, H. Jonsson, B. Lafleur, M. Loewenstein, J. Podolske, E. Atlas, K. Boering, G. Toon, D. Fahey, T. Bui, G. Diskin, F. Moore

Shan-Hu Lee

Measurements of aerosol, N2O and OCS made in the Northern Hemisphere below 21 km altitude following the eruption of Pinatubo are presented and analyzed. After September 1999, the oxidation of OCS and sedimentation of particles in the extra-tropical overworld north of 45 N are found to maintain the aerosol in a steady state. This analysis empirically links precursor gas to aerosol abundance throughout this region. These processes are tracked with age-of-air which offers advantages over tracking as a function of latitude and altitude. In the extra-tropical, lowermost stratosphere, normalized volume distributions appear constant in time after the fall of 1999. …


Ternary Homogeneous Nucleation Of H2so4, Nh3, And H2o Under Conditions Relevant To The Lower Troposphere, D. Benson, J. Yu, A. Markovich, Shan-Hu Lee Oct 2013

Ternary Homogeneous Nucleation Of H2so4, Nh3, And H2o Under Conditions Relevant To The Lower Troposphere, D. Benson, J. Yu, A. Markovich, Shan-Hu Lee

Shan-Hu Lee

Ternary homogeneous nucleation (THN) of H2SO4, NH3 and H2O has been used to explain new particle formation in various atmospheric regions, yet laboratory measurements of THN have failed to reproduce atmospheric observations. Here, we report first laboratory observations of THN made under conditions relevant to the lower troposphere ([H2SO4] of 106–107 cm−3, [NH3] of 0.08–20 ppbv, and a temperature of 288 K). Our observations show that NH3 can enhance atmospheric H2SO4aerosol nucleation and the enhancement factor (EF) in nucleation rate (J) due to NH3 (the ratio of Jmeasured with vs. without NH3) increases linearly with increasing [NH3] and increases with …


Eight Aggies Honored In 2013 Nsf Graduate Research Fellow Search, Michael Negale Jul 2013

Eight Aggies Honored In 2013 Nsf Graduate Research Fellow Search, Michael Negale

Michael Negale

No abstract provided.


Usu Grad Student, Researchers Collect Project Data At South Pole, Kevin Opsahl Mar 2013

Usu Grad Student, Researchers Collect Project Data At South Pole, Kevin Opsahl

Jonathan Pugmire

No abstract provided.


Usu Grad Student Travels To South Pole, Kylie Conway Mar 2013

Usu Grad Student Travels To South Pole, Kylie Conway

Jonathan Pugmire

No abstract provided.


Usu Team Travels To South Pole To Measure Gravity Waves, Nancy Van Valkenburg Mar 2013

Usu Team Travels To South Pole To Measure Gravity Waves, Nancy Van Valkenburg

Jonathan Pugmire

No abstract provided.


A Statistical Model To Forecast Short-Term Atlantic Hurricane Intensity, Kevin Law, Jay Hobgood Aug 2012

A Statistical Model To Forecast Short-Term Atlantic Hurricane Intensity, Kevin Law, Jay Hobgood

Kevin Law

An alternative 24-h statistical hurricane intensity model is presented and verified for 13 hurricanes during the 2004–05 seasons. The model uses a new method involving a discriminant function analysis (DFA) to select from a collection of multiple regression equations. These equations were developed to predict the future 24-h wind speed increase and the 24-h pressure drop that were constructed from a dataset of 103 hurricanes from 1988 to 2003 that utilized 25 predictors of rapid intensification. The accuracy of the 24-h wind speed increase models was tested and compared with the official National Hurricane Center (NHC) 24-h intensity forecasts, which …


The Impact Of Oceanic Heat Content On The Rapid Intensification Of Atlantic Hurricanes, Kevin Law Aug 2012

The Impact Of Oceanic Heat Content On The Rapid Intensification Of Atlantic Hurricanes, Kevin Law

Kevin Law

With the increased infrastructure and amount of people living along the United States coastline, it is imperative to improve the accuracy of Atlantic hurricane intensity forecasts. Over the last 10 years, there have been many Atlantic hurricanes, including Hurricanes Katrina and Charley that surprised many forecasters with their rapid intensification and power. The rapid intensification of tropical cyclones is the most serious aspect, when it comes to forecasting. It is generally accepted that sufficient surface ocean temperatures (approximately 26°C) are needed to produce and sustain tropical cyclone formation. However, the sea-surface temperature (SST) has shown not to be critical in …


Book Review: The Great Warming: Climate Change And The Rise And Fall Of Civilizations, James Fleming Feb 2009

Book Review: The Great Warming: Climate Change And The Rise And Fall Of Civilizations, James Fleming

James R. Fleming

No abstract provided.


Dialogue Television: The Climate Engineers, James Fleming Apr 2007

Dialogue Television: The Climate Engineers, James Fleming

James R. Fleming

The problem of global warming is getting massive public attention. This comes forty years after the first major government report outlining the problem. But there is considerable disagreement over what steps should be taken to mitigate the problem and some scientist fear that politicians are not displaying sufficient urgency. James Fleming describes the technological quick fixes proposed by some scientists and the problems they might create.


The Climate Engineers: Playing God To Save The Planet, James Fleming Dec 2006

The Climate Engineers: Playing God To Save The Planet, James Fleming

James R. Fleming

As alarm over global warming spreads, a radical idea is gaining momentum. Forget cuts in greenhouse-gas emissions, some scientists argue. Find a technological fix. Bounce sunlight back into space by pumping reflective nanoparticles into the atmosphere. Launch mirrors into orbit around the earth. Create a “planetary thermostat.” But what sounds like science fiction is actually an old story. For more than a century, scientists, soldiers, and charlatans have hatched schemes to manipulate the weather and climate. Like them, today’s aspiring climate engineers wildly exaggerate what is possible, and they scarcely consider political, military, and ethical implications of attempting to manage …