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Wilbert R. Skinner

Bio: Wilbert R. Skinner is an academic researcher from University of Michigan. The author has contributed to research in topics: Thermosphere & Mesosphere. The author has an hindex of 35, co-authored 85 publications receiving 3836 citations.


Papers
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Journal ArticleDOI
TL;DR: The Horizontal Wind Model (HWM07) as mentioned in this paper provides a statistical representation of the horizontal wind fields of the Earth's atmosphere from the ground to the exosphere (0-500 km).
Abstract: [1] The new Horizontal Wind Model (HWM07) provides a statistical representation of the horizontal wind fields of the Earth's atmosphere from the ground to the exosphere (0–500 km). It represents over 50 years of satellite, rocket, and ground-based wind measurements via a compact Fortran 90 subroutine. The computer model is a function of geographic location, altitude, day of the year, solar local time, and geomagnetic activity. It includes representations of the zonal mean circulation, stationary planetary waves, migrating tides, and the seasonal modulation thereof. HWM07 is composed of two components, a quiet time component for the background state described in this paper and a geomagnetic storm time component (DWM07) described in a companion paper.

490 citations

Journal ArticleDOI
TL;DR: The high-resolution Doppler imager (HRDI) on the Upper Atmosphere Research Satellite is a triple-etalon Fabry-Perot interferometer designed to measure winds in the stratosphere, mesosphere, and lower thermosphere.
Abstract: The high-resolution Doppler imager (HRDI) on the Upper Atmosphere Research Satellite is a triple-etalon Fabry-Perot interferometer designed to measure winds in the stratosphere, mesosphere, and lower thermosphere. Winds are determined by measuring the Doppler shifts of rotational lines of the O2 atmospheric band, which are observed in emission in the mesosphere and lower thermosphere and in absorption in the stratosphere. The interferometer has high resolution (0.05/cm), good offhand rejection, aud excellent stability. This paper provides details of the design and capabilities of the HRDI instrument.

296 citations

Journal ArticleDOI
TL;DR: The global scale wave model (GSWM) as mentioned in this paper represents the first numerical modeling attempt at simulating this seasonal variability, and a preliminary comparison of the GSWM tidal results with HRDI measurements is presented.
Abstract: Observations of the mesosphere and lower thermosphere winds obtained by the High Resolution Doppler Imager (HRDI) on the Upper Atmosphere Research Satellite (UARS) during 1991 to 1995 reveal a semiannual variation in the amplitude of the (1,1) diurnal tide. The global-scale wave model (GSWM) represents the first numerical modeling attempt at simulating this seasonal variability, and a preliminary comparison of the GSWM tidal results with HRDI measurements is presented. The results of the comparison and of numerical tests point to some vital and unresolved questions regarding tidal dissipation and tropospheric forcing. In addition to the seasonal variability, HRDI has revealed a strong interannual modulation of the diurnal tide with amplitudes observed to change by nearly a factor of 2 from 1992 to 1994.

228 citations

Journal ArticleDOI
TL;DR: The 5-day planetary wave has been detected in the winds measured by the High Resolution Doppler Imager (HRDI) on the Upper Atmosphere Research Satellite (UARS) in the mesosphere and lower thermosphere (50-110 kin) as discussed by the authors.
Abstract: The 5-day planetary wave has been detected in the winds measured by the High Resolution Doppler Imager (HRDI) on the Upper Atmosphere Research Satellite (UARS) in the mesosphere and lower thermosphere (50-110 kin) The appearances of the 5-day wave are transient, with a lifetime of 10-20 days in the two-year data set The structures of selected 5-day wave events are in generally good agreement with the (1,1) Rossby normal mode for both zonal and meridional components A climatology of the 5-day wave is presented for an altitude of 95 km and latitudes mainly between 40oS and 40oN

161 citations

Journal ArticleDOI
TL;DR: In this article, the authors used the high resolution Doppler imager (HRDI) on the Upper Atmosphere Research Satellite (UARS) has provided measurements of the horizontal wind field in the stratosphere, mesosphere, and lower thermosphere since November 1991.
Abstract: The high resolution Doppler imager (HRDI) on the Upper Atmosphere Research Satellite (UARS) has provided measurements of the horizontal wind field in the stratosphere, mesosphere, and lower thermosphere since November 1991. This data set, which spans a period of more than 3 years, has facilitated an investigation of the long-term behavior of the background circulation on a nearly global basis. At middle and high latitudes the zonal circulation is characterized by an annual oscillation. At low latitudes (±30°) the most prominent long-term variation above the stratopause is the mesosphere semiannual oscillation (MSAO), which maximizes near the equator at an altitude of between 80 and 85 km. Further analysis of the time series reveals an additional strong variation, with an amplitude near 30 ms−1 and a period of about 2 years. This feature shows the same altitude and latitude structure as the MSAO and exhibits a phase relationship with the stratospheric quasi-biennial oscillation (QBO). Observations from the Christmas Island MF radar (2°N, 130°W) confirm the presence of this mesospheric QBO (MQBO). These observations support recent findings from a modeling study which generates an MQBO via the selective filtering of small-scale gravity waves by the underlying winds they traverse.

160 citations


Cited by
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Journal ArticleDOI
TL;DR: The quasi-biennial oscillation (QBO) as discussed by the authors dominates the variability of the equatorial stratosphere (∼16-50 km) and is easily seen as downward propagating easterly and westerly wind regimes, with a variable period averaging approximately 28 months.
Abstract: The quasi-biennial oscillation (QBO) dominates the variability of the equatorial stratosphere (∼16–50 km) and is easily seen as downward propagating easterly and westerly wind regimes, with a variable period averaging approximately 28 months. From a fluid dynamical perspective, the QBO is a fascinating example of a coherent, oscillating mean flow that is driven by propagating waves with periods unrelated to that of the resulting oscillation. Although the QBO is a tropical phenomenon, it affects the stratospheric flow from pole to pole by modulating the effects of extratropical waves. Indeed, study of the QBO is inseparable from the study of atmospheric wave motions that drive it and are modulated by it. The QBO affects variability in the mesosphere near 85 km by selectively filtering waves that propagate upward through the equatorial stratosphere, and may also affect the strength of Atlantic hurricanes. The effects of the QBO are not confined to atmospheric dynamics. Chemical constituents, such as ozone, water vapor, and methane, are affected by circulation changes induced by the QBO. There are also substantial QBO signals in many of the shorter-lived chemical constituents. Through modulation of extratropical wave propagation, the QBO has an effect on the breakdown of the wintertime stratospheric polar vortices and the severity of high-latitude ozone depletion. The polar vortex in the stratosphere affects surface weather patterns, providing a mechanism for the QBO to have an effect at the Earth's surface. As more data sources (e.g., wind and temperature measurements from both ground-based systems and satellites) become available, the effects of the QBO can be more precisely assessed. This review covers the current state of knowledge of the tropical QBO, its extratropical dynamical effects, chemical constituent transport, and effects of the QBO in the troposphere (∼0–16 km) and mesosphere (∼50–100 km). It is intended to provide a broad overview of the QBO and its effects to researchers outside the field, as well as a source of information and references for specialists. The history of research on the QBO is discussed only briefly, and the reader is referred to several historical review papers. The basic theory of the QBO is summarized, and tutorial references are provided.

1,744 citations

Journal ArticleDOI
TL;DR: In this paper, the global scale wave model (GSWM) is used to investigate mesospheric and lower thermospheric migrating and non-migrating diurnal tidal components that propagate upward from the troposphere, where they are excited by latent heat release associated with deep tropical convection.
Abstract: [1] The global-scale wave model (GSWM) is used to investigate mesospheric and lower thermospheric migrating and nonmigrating diurnal tidal components that propagate upward from the troposphere, where they are excited by latent heat release associated with deep tropical convection. Our diurnal tidal forcing parameterization is derived from a 7-year database of global cloud imagery. The GSWM migrating response is sufficiently large to modulate the dominant radiatively excited migrating diurnal tide in the middle and upper atmosphere during every month of the year. Five additional nonmigrating diurnal components, the eastward propagating zonal wave numbers 2 and 3, the westward propagating zonal wave number 2, and the standing oscillations, also introduce significant longitudinal variability of the diurnal tide in these regions. The comparative importance of the nonmigrating components evolves from month to month and varies with tidal field. Our GSWM investigation suggests that other dynamical models must account for the tropospheric latent heat source in order to make realistic predictions of the diurnal tide in the middle and upper atmosphere.

789 citations

01 Jan 2002
TL;DR: In this paper, the authors provide a primer on radiative transfer: absorption and scattering opacity, Stokes parameters, Poincare sphere, and the Mueller matrix, as well as the principle of reciprocity for the bidirectional reflectance.
Abstract: Preface 1. Basic properties of radiation, atmospheres and oceans 2. Basic state variables 3. Interaction of radiation with matter 4. Formulation of radiative transfer problems 5. Approximate solutions of prototype problems 6. Accurate numerical solutions of prototype problems 7. Emission-dominated radiative processes 8. Radiative transfer in spectrally-complex media 9. Solar radiation driving photochemistry and photobiology 10. The role of radiation in climate Appendix 1. A primer on radiative transfer: absorption and scattering opacity Appendix 2. Stokes parameters, Poincare sphere, and the Mueller matrix Appendix 3. Nomenclature: glossary of symbols Appendix 4. Principle of reciprocity for the bidirectional reflectance Appendix 5. Isolation of the azimuth-dependence Appendix 6. The streaming term in spherical geometry Appendix 7. Reflectance and transmittance of the invariant intensity (I n2) Appendix 8. Scaling transformation for anisotropic scattering Appendix 9. Reciprocity, duality and effects of surface reflection Appendix 10. Removal of overflow problems in the intensity formulas.

515 citations

Book
13 Aug 1999
TL;DR: In this paper, the authors provide a primer on radiative transfer: absorption and scattering opacity, Stokes parameters, Poincare sphere, and the Mueller matrix, as well as the principle of reciprocity for the bidirectional reflectance.
Abstract: Preface 1. Basic properties of radiation, atmospheres and oceans 2. Basic state variables 3. Interaction of radiation with matter 4. Formulation of radiative transfer problems 5. Approximate solutions of prototype problems 6. Accurate numerical solutions of prototype problems 7. Emission-dominated radiative processes 8. Radiative transfer in spectrally-complex media 9. Solar radiation driving photochemistry and photobiology 10. The role of radiation in climate Appendix 1. A primer on radiative transfer: absorption and scattering opacity Appendix 2. Stokes parameters, Poincare sphere, and the Mueller matrix Appendix 3. Nomenclature: glossary of symbols Appendix 4. Principle of reciprocity for the bidirectional reflectance Appendix 5. Isolation of the azimuth-dependence Appendix 6. The streaming term in spherical geometry Appendix 7. Reflectance and transmittance of the invariant intensity (I n2) Appendix 8. Scaling transformation for anisotropic scattering Appendix 9. Reciprocity, duality and effects of surface reflection Appendix 10. Removal of overflow problems in the intensity formulas.

510 citations

Journal ArticleDOI
TL;DR: In this paper, the Horizontal Wind Model (HWM) has been updated in the thermosphere with new observations and formulation changes, including ground-based 630 nm Fabry-Perot Interferometer (FPI) measurements in the equatorial and polar regions, as well as cross track winds from the Gravity Field and Steady State Ocean Circulation Explorer (GOCE) satellite.
Abstract: The Horizontal Wind Model (HWM) has been updated in the thermosphere with new observations and formulation changes. These new data are ground-based 630 nm Fabry-Perot Interferometer (FPI) measurements in the equatorial and polar regions, as well as cross-track winds from the Gravity Field and Steady State Ocean Circulation Explorer (GOCE) satellite. The GOCE wind observations provide valuable wind data in the twilight regions. The ground-based FPI measurements fill latitudinal data gaps in the prior observational database. Construction of this reference model also provides the opportunity to compare these new measurements. The resulting update (HWM14) provides an improved time-dependent, observationally based, global empirical specification of the upper atmospheric general circulation patterns and migrating tides. In basic agreement with existing accepted theoretical knowledge of the thermosphere general circulation, additional calculations indicate that the empirical wind specifications are self-consistent with climatological ionosphere plasma distribution and electric field patterns.

496 citations