A5006615242- Atmospheric Ozone and Climate
- Ionosphere and magnetosphere dynamics
- Astro and Planetary Science
- Solar and Space Plasma Dynamics
- Planetary Science and Exploration
- Geomagnetism and Paleomagnetism Studies
- Atmospheric and Environmental Gas Dynamics
- Atmospheric chemistry and aerosols
- Geophysics and Gravity Measurements
- Meteorological Phenomena and Simulations
- Isotope Analysis in Ecology
- Atmospheric aerosols and clouds
- Radiative Heat Transfer Studies
- Climate variability and models
- Geology and Paleoclimatology Research
- Gas Dynamics and Kinetic Theory
- Laser Material Processing Techniques
- Nuclear physics research studies
- Spacecraft and Cryogenic Technologies
- Traffic control and management
- Enhanced Oil Recovery Techniques
- Ocean Waves and Remote Sensing
- Methane Hydrates and Related Phenomena
- Spectroscopy and Quantum Chemical Studies
- Hydraulic Fracturing and Reservoir Analysis
Johns Hopkins University Applied Physics Laboratory
2009-2024
PetroChina Southwest Oil and Gas Field Company (China)
2023
Johns Hopkins University
1994-2022
The University of Texas at San Antonio
2022
Jiangsu Normal University
2014-2015
United States Naval Research Laboratory
1993-1997
University of Wuppertal
1997
Kyoto University
1997
Computational Physics (United States)
1997
Space Telescope Science Institute
1994
New Horizons unveils the Pluto system In July 2015, spacecraft flew through at high speed, humanity's first close look this enigmatic on outskirts of our solar system. a series papers, team present their analysis encounter data downloaded so far: Moore et al. complex surface features and geology its large moon Charon, including evidence tectonics, glacial flow, possible cryovolcanoes. Grundy analyzed colors chemical compositions surfaces, with ices H 2 O, CH 4 , CO, N NH 3 reddish material...
The Voyager 1 ultraviolet spectrometer (UVS) solar occultation and airglow data obtained during the Titan flyby are analyzed for composition thermal structure of upper atmosphere relative importance excitation processes. From optical depth profiles inferred by Smith et al. (1982, J. Geophys. Res. 87, 1351–1359) evening terminator, entrance occulatation, an asymptotic temperature T∞ = 175 K, a CH4 mixing ratio increasing from 0.06 ± 0.01 at 1000 km to 0.20 0.02 1400 derived. not sufficient...
A radiative-thermal conduction model for the vertical thermal structure of Io's atmosphere is developed with solar heating by SO2 absorption in UV and near-IR bands non-LTE cooling SO2v1 , v2, v3, vibrational rotational lines. The predicts existence a mesopause when surface pressure exceeds ∼10 nbar. radiative time constant establishing mesosphere/mesopause on Io only ∼20 min, whereas thermaspheric about 1 hr. These constants are significantly shorter than diurnal scale competitive dynamical...
A radiative–conductive model for the vertical thermal structure of Pluto's atmosphere is developed with a non-LTE treatment solar heating in CH43.3 μm and 2.3 bands, radiative exchange cooling CH47.6 band, LTE by CO rotational line emission. The includes effects opacity vibrational energy transfer CH4molecule. Partial thermalization absorbed radiation bands rapid from stretch modes to bending generates high altitude at sub-microbar pressures. Heating exceeds 3.3 approximately factor 6 occurs...
Observations of the trailing hemisphere Io made with Faint Object Spectrograph Hubble Space Telescope in March 1992 have resulted first detection atmospheric SO2 absorption bands ultraviolet. These observations represent only third positive means what is widely believed to be Io's primary constituent. Below ∼2130 Å geometric albedo satellite dominated by gas band signatures, which been analyzed using models that include effects optical thickness, temperature, and spatial distribution. The...
Previous observations of atmospheric oscillations with zonal wave number 1 have consistently located waves periods between 5 and 7 days. This study presents a global seasonal analysis the 6.5‐day in High Resolution Doppler Imager daytime mesosphere lower thermosphere horizontal winds, temperatures, nighttime atomic oxygen at 95 km. The structures all these variables are similar to gravest symmetric Rossby wave, i.e., (1,1) mode. spatial displays possible modification by mean wind. Finally,...
Lindzen's parameterization for the drag and eddy diffusion produced by breaking internal gravity waves in mesosphere lower thermosphere is applied to a modified version of β-plane channel model Holton which an isotropic source spectrum specified similar that given 1982 Matsuno. The transmission each wave component influenced Newtonian cooling induced other components. In general with smallest Doppler-shifted phase speeds break first produce sufficient significantly raise heights higher speed...
We examine the role of geostrophic adjustment in middle atmosphere for given wave packet forcing by a three-dimensional hydrostatic model. The problem is solved directly so that solutions are expressed as convolution integrals Green's function and external forcing. It shown induced fields consist two different kinds modes. One, produced vorticity only, steady quasi-geostrophic flow;, this restricted to region. other, both divergence, oscillatory, form gravity waves propagating out region...
Recent observations of CH 4 and HF from the UARS Halogen Limb Occultation Experiment (HALOE) suggest that vigorous descent occurs within polar winter vortex with “mesospheric” values evident down to 30 mbar. This study shows a highly accurate two‐dimensional model advection scheme coupled modern radiation scheme, parameterized planetary gravity wave drag algorithms can produce tracer distributions consistent HALOE observations. The modeled distribution is found be principally dependent on...
The 6.5‐day wave is a westward propagating zonal number 1 ( s = 1) planetary that prominent near equinox. spatial‐temporal structure of the seen in United Kingdom Meteorological Office (UKMO) data stratosphere found to be consistent with obtained from Upper Atmosphere Research Satellite/High Resolution Doppler Imager (HRDI) measurements horizontal winds and temperatures mesosphere/lower thermosphere (MLT). Two events are commonly observed before after equinox at low latitudes both UKMO HRDI...
Radiative damping rates of temperature perturbations are calculated by CO2 and O3 Curtis matrices extending from the surface to 120 km in earth's atmosphere with eigenvalue scale-dependent Newtonian cooling methods at 0.5 vertical resolution. Based on latest value deactivation rate bending mode atomic oxygen, radiative region 90–100 is ∼1.3 day −1 due near-local thermodynamic equilibrium nature 15-μm band emission. This comparable induced eddy molecular diffusion ∼2.5 day−1 corresponding...
An accurate, efficient, and user-friendly radiation algorithm is developed for calculating net radiative heating rate in middle atmosphere models. The Curtis matrix interpolation scheme originally by Zhu adopted with explicit temperature dependence the calculation of CO2 15-μm band atmospheric cooling rate. O3 9.6-μm calculated a includes variations ozone mixing ratio. water vapor rotational 6.3-μm vibrational to H2O ratio variation. All matrices are referenced basic state correlated k...
Abstract Polar mesospheric clouds (PMCs) occur in the summer near 82 ‐85km altitude due to seasonal changes of temperature and humidity. However, water vapor associated PMCs have also been observed with rocket exhaust. The effects this exhaust on upper mesosphere are not well understood. To investigate these effects, 220 kg pure was explosively released at 85 km as part Super Soaker sounding experiment night January 25–26, 2018 Poker Flat Research Range (65°N, 147°W). A cloud formed within...
Abstract We propose a modification to the simultaneous perturbation stochastic approximation (SPSA) methods based on comparisons made between first‐ and second‐order SPSA (1SPSA 2SPSA) algorithms from perspective of loss function Hessian. At finite iterations, accuracy algorithm depends matrix conditioning The error 2SPSA for with an ill‐conditioned Hessian is greater than one well‐conditioned On other hand, 1SPSA less sensitive Hessians. modified (M2SPSA) eliminates amplification caused by...
A new theory of the saturated vertical wavenumber spectrum gravity waves for middle atmosphere is developed. The based on a hypothesis that result balance among various spectral sources and sinks in atmosphere. source included this paper amplification upward propagating due to density effect. Two are off-resonant wave-wave interactions scale-dependent radiative damping. It found algebraic approximation horizontal winds, F(μ), can be written as Fμμ−3θμ2−1 ,where μ dimensionless wavenumber, θ...