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Robert R. O'Neil

Bio: Robert R. O'Neil is an academic researcher from Air Force Research Laboratory. The author has contributed to research in topics: Radiance & Radiometer. The author has an hindex of 6, co-authored 17 publications receiving 459 citations.

Papers
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Journal ArticleDOI
TL;DR: In this article, Mill et al. discuss the effects of environmental pollution on the environment and propose an approach to mitigate the environmental impact of greenhouse gas emissions in the air and water.
Abstract: John D. Mill* Environmental Research Institute of Michigan, Arlington, Virginia 22209 Robert R. O'Neil* and Stephan Price* U.S. Air Force Phillips Laboratory, HanscomAFB, Massachusetts 01731 Gerald J. Romick and O. Manuel Uy Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland 20723 E. M. Gaposchkin** Massachusetts Institute of Technology, Lexington, Massachusetts 02173 Glenn C. Light The Aerospace Corporation, Los Angeles, California 90009-2970 W. Walding Moore Jr.** U.S. Army Space and Strategic Defense Command, Huntsville, Alabama 35807-3801 Thomas L. Murdock General Research Corporation, Danvers, Massachusetts 01923 and A. T. Stair Jr. Visidyne, Burlington, Massachusetts 01803

217 citations

Journal ArticleDOI
TL;DR: In this paper, the first observations of thunderstorm-generated gravity waves imaged from space have been provided by data from the Midcourse Space Experiment (MSX) and two instances of such patterns have been identified.
Abstract: Data from the Midcourse Space Experiment (MSX) has provided the first observations of thunderstorm-generated gravity waves imaged from space. Gravity wave theory predicts that isolated, sufficiently convective thunderstorms can launch waves and create a unique intensity pattern of concentric circles on a radiating surface of constant altitude above such a storm. Among the MSX constant-nadir-angle mid-wave infrared (MWIR) observations, two instances of such patterns have been identified. It was confirmed from meteorological satellite images that highly convective isolated thunderstorms occurred at the locations and times expected.

181 citations

Journal ArticleDOI
TL;DR: In this paper, the MSX 4.3-µm spectral region has been imaged by the SPIRIT 3 radiometer on the satellite observing the cloud-free atmosphere.
Abstract: Distinctive structure in the 4.3-µm spectral region has been imaged by the SPIRIT 3 radiometer on the MSX satellite observing the cloud-free atmosphere. We show nadir, high-nadir-angle (NA) sublimb, and limb images which, coupled with radiative transfer analysis, indicate that this structure originates from internal gravity waves (GWs). Such structure occurs in a significant fraction of both below-the-horizon (BTH), or sublimb, and above-the-horizon (ATH), or limb, observations in both MSX 4.3-µm channels. The structure has different morphology from clouds and has spatial scales appropriate for atmospheric GWs. Calculation of contribution functions (CFs), or weighting functions, for MSX filters and viewing conditions confirms that the BTH GW structure originates from altitudes near 40 km. We believe this is the first high-resolution imaging of atmospheric GWs from space in the mid-wave infrared (MWIR) spectral region. In addition, the technique provides structure imaging capabilities at upper stratospheric altitudes inaccessible to airglow imagery.

30 citations

Journal ArticleDOI
TL;DR: In this paper, the authors derived the energy flux, energy flux Q (ergs cm -2 s -1 ), the average energy (E) (keV) of the incident electrons, as well as the location of the dosed region along the line of sight (LOS) were previously derived.
Abstract: Enhanced medium-wave infrared nitric oxide fundamental (Δv = -1) vibration-rotation (VR) band emission observed by the Midcourse Space Experiment radiometer band A (6.8-10.8 μm) at nighttime in the 110- to 130-km tangent altitude range on November 10, 1996, is shown to be the result of auroral dosing. The energy flux Q (ergs cm -2 s -1 ), the average energy (E) (keV) of the incident electrons, as well as the location of the dosed region along the line of sight (LOS) were previously derived [Strickland et al., 1997]. Combining these results with the N + 2 first negative band emission at 391.4 nm gives the auroral energy deposition rate in all three spatial dimensions. The portion of the LOS NO VR band radiance transmitted by the band A filter calculated by a more elaborate version of the auroral model in the Strategic High-Altitude Radiance Code agrees remarkably well with the enhancements in the signal observed in that band of the Spatial Infrared Imaging Telescope III radiometer.

11 citations

01 Dec 2001
TL;DR: In this paper, an extensive database on spatial structure in the infrared radiance of the middle and upper atmosphere has been collected by the Mid-Course Space Experiment (MSX), which contains spatial structure down to the scale of hundreds of meters.
Abstract: An extensive database on spatial structure in the infrared radiance of the middle and upper atmosphere has been collected by the Mid-Course Space Experiment (MSX). The observed radiance contains spatial structure down to the scale of hundreds of meters. This spatial structure results from local fluctuations in the temperature and densities of the radiating states of the emitting molecular species as well as fluctuations in radiation transport from the emitting regions to the observer. A portion of this database has been analyzed to obtain statistical parameters characterizing stochastic spatial structure in the observed radiance. Using simple models, the observed statistics have been shown to agree with prior observations and theoretical models of stochastic spatial structure generated by gravity waves for special viewing geometries. The SHARC model has been extended to predict the statistics of stochastic fluctuations in infrared radiance from the statistics characterizing temperature fluctuations in the middle and upper atmosphere for arbitrary viewing geometries. SHARC model predictions have been compared with MSX data and shown to be in generally good agreement. Additional work is in progress to account for the statistics characterizing small spatial scale fluctuations.

7 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, a review of gravity wave sources and characteristics, the evolution of the gravity wave spectrum with altitude and with variations of wind and stability, the character and implications of observed climatologies, and the wave interaction and instability processes that constrain wave amplitudes and spectral shape are discussed.
Abstract: [1] Atmospheric gravity waves have been a subject of intense research activity in recent years because of their myriad effects and their major contributions to atmospheric circulation, structure, and variability. Apart from occasionally strong lower-atmospheric effects, the major wave influences occur in the middle atmosphere, between ∼ 10 and 110 km altitudes because of decreasing density and increasing wave amplitudes with altitude. Theoretical, numerical, and observational studies have advanced our understanding of gravity waves on many fronts since the review by Fritts [1984a]; the present review will focus on these more recent contributions. Progress includes a better appreciation of gravity wave sources and characteristics, the evolution of the gravity wave spectrum with altitude and with variations of wind and stability, the character and implications of observed climatologies, and the wave interaction and instability processes that constrain wave amplitudes and spectral shape. Recent studies have also expanded dramatically our understanding of gravity wave influences on the large-scale circulation and the thermal and constituent structures of the middle atmosphere. These advances have led to a number of parameterizations of gravity wave effects which are enabling ever more realistic descriptions of gravity wave forcing in large-scale models. There remain, nevertheless, a number of areas in which further progress is needed in refining our understanding of and our ability to describe and predict gravity wave influences in the middle atmosphere. Our view of these unknowns and needs is also offered.

2,206 citations

Journal ArticleDOI
TL;DR: In this article, the authors start from six absolutely calibrated continuous stellar spectra from 1.2 to 35?m for K0, K1.5, K3, K5, and M0 giants, and normalize each template by photometry for the individual stars using published and/or newly secured near and mid-infrared photometry obtained through fully characterized, absolutely calibrated, combinations of filter passband, detector radiance response, and mean terrestrial atmospheric transmission.
Abstract: We start from our six absolutely calibrated continuous stellar spectra from 1.2 to 35 ?m for K0, K1.5, K3, K5, and M0 giants. These were constructed as far as possible from actual observed spectral fragments taken from the ground, the Kuiper Airborne Observatory, and the IRAS Low Resolution Spectrometer, and all have a common calibration pedigree. From these we spawn 422 calibrated spectral templates for stars with spectral types in the ranges G9.5?K3.5 III and K4.5?M0.5 III. We normalize each template by photometry for the individual stars using published and/or newly secured near- and mid-infrared photometry obtained through fully characterized, absolutely calibrated, combinations of filter passband, detector radiance response, and mean terrestrial atmospheric transmission. These templates continue our ongoing effort to provide an all-sky network of absolutely calibrated, spectrally continuous, stellar standards for general infrared usage, all with a common, traceable calibration heritage. The wavelength coverage is ideal for calibration of many existing and proposed ground-based, airborne, and satellite sensors, particularly low- to moderate-resolution spectrometers. We analyze the statistics of probable uncertainties, in the normalization of these templates to actual photometry, that quantify the confidence with which we can assert that these templates truly represent the individual stars. Each calibrated template provides an angular diameter for that star. These radiometric angular diameters compare very favorably with those directly observed across the range from 1.6 to 21 mas.

585 citations

Journal ArticleDOI
TL;DR: In this article, the authors presented a panoramic image of the entire Galactic plane within 5° in four mid-infrared spectral bands between 6 and 25 μm at a spatial resolution of ~183, which was redundant within |b| ≤ 45 with fourfold coverage over two-thirds of the area.
Abstract: The Midcourse Space Experiment (MSX) surveyed the entire Galactic plane within |b| ≤ 5° in four mid-infrared spectral bands between 6 and 25 μm at a spatial resolution of ~183. The survey was redundant within |b| ≤ 45 with four-fold coverage over two-thirds of the area. These survey data were combined to create 1680 15 × 15 images that cover the region with 6'' pixel spacing in each of the spectral bands. The images preserve the inherent resolution of the data but have up to twice the sensitivity of a single scan. The individual survey observations had to be extensively conditioned to achieve the co-add advantage. The noise equivalent radiance (NER) at 8.3 μm, the most sensitive MSX mid-infrared spectral band, varies from ~1.3 MJy sr-1 in the inner Galaxy to 3 times that at the latitude limits in the outer Galaxy; the sensitivities of the other MSX mid-infrared bands are 10–25 times less. Additionally, 36 lower resolution 10° × 10° images were generated in each band that span the full latitude and longitude range of the survey. These panoramic images have a resolution of ~12 with 36'' pixel spacing and a six-fold improvement in NER, making them an ideal product for comparison with radio surveys of the Galactic plane. An ancillary set of images has been created from other MSX astronomy experiments that lie within 10° of the Galactic plane. These images either extend the latitude coverage of the survey or provide deeper probes of Galactic structure either by themselves or when added to the survey images.

523 citations

Journal ArticleDOI
TL;DR: In this article, a review of gravity-wave effects in stratosphere-resolving climate models, recent observations and analysis methods that reveal global patterns in gravitywave momentum fluxes and results of very-high-resolution model studies, and outline some future research requirements to improve the treatment of these waves in climate simulations.
Abstract: Recent observational and theoretical studies of the global properties of small-scale atmospheric gravity waves have highlighted the global effects of these waves on the circulation from the surface to the middle atmosphere. The effects of gravity waves on the large-scale circulation have long been treated via parametrizations in both climate and weather-forecasting applications. In these parametrizations, key parameters describe the global distributions of gravity-wave momentum flux, wavelengths and frequencies. Until recently, global observations could not define the required parameters because the waves are small in scale and intermittent in occurrence. Recent satellite and other global datasets with improved resolution, along with innovative analysis methods, are now providing constraints for the parametrizations that can improve the treatment of these waves in climate-prediction models. Research using very-high-resolution global models has also recently demonstrated the capability to resolve gravity waves and their circulation effects, and when tested against observations these models show some very realistic properties. Here we review recent studies on gravity-wave effects in stratosphere-resolving climate models, recent observations and analysis methods that reveal global patterns in gravity-wave momentum fluxes and results of very-high-resolution model studies, and we outline some future research requirements to improve the treatment of these waves in climate simulations. Copyright © 2010 Royal Meteorological Society and Crown in the right of Canada

467 citations

Journal ArticleDOI
TL;DR: In this paper, the authors find dense (n > 105 cm−3), cold (T < 20 K) cores, without accompanying envelopes, in a 1° × 180° scan along the Galactic equator.
Abstract: Recent observations by the Midcourse Space Experiment (MSX) have revealed the presence of compact objects seen in absorption against bright mid-infrared emission from the Galactic plane. Examination of MSX and IRAS images of these objects reveal that they are dark from 7 to 100 μm. We find ~2000 clouds in a 1° × 180° scan along the Galactic equator. The data suggest these objects are dense (n > 105 cm−3), cold (T<20 K) cores, without accompanying envelopes.

455 citations