A5069331774- Ionosphere and magnetosphere dynamics
- Atmospheric Ozone and Climate
- Climate variability and models
- Solar and Space Plasma Dynamics
- Meteorological Phenomena and Simulations
- Geophysics and Gravity Measurements
- Geomagnetism and Paleomagnetism Studies
- Planetary Science and Exploration
- Astro and Planetary Science
- Ocean Waves and Remote Sensing
Yonsei University
2016-2024
Korea Polar Research Institute
2019-2021
Abstract The role of gravity waves (GWs) in a sudden stratospheric warming (SSW) event that occurred January 2009 (SSW09) is investigated using the MERRA-2 dataset. Nearly 2 weeks prior to central date (lag = 0), at which zonal-mean zonal wind 10 hPa and 60°N first becomes negative, westward GW drag (GWD) significantly enhanced lower mesosphere stratosphere. At 5 days before lag 0, planetary (PWs) wavenumber (ZWN-2) stratosphere are enhanced, while PWs ZWN-1 weakened, evident from amplitudes...
Abstract Gravity wave (GW) activities in the upper mesosphere (80–100 km) and their potential sources are investigated using meteor radar observations at King Sejong Station, Antarctica (KSS; 62.22°S, 58.78°W) during recent 14 years (2007–2020). GW estimated by horizontal wind variances of small‐scale GWs (periods <2 h, wavelength <400 km, or vertical <3–5 km). The show clear semiannual variations with maxima solstices, annual also seen above z = 90 km. deseasonalized 96.8 km have a...
Abstract. Seasonal variation in westward-propagating quasi-10 d waves (Q10DWs) the mesosphere and lower thermosphere of Southern Hemisphere (SH) high-latitude regions is investigated using meteor radar (MR) observations for period 2012–2016 Specified Dynamics (SD) version Whole Atmosphere Community Climate Model (WACCM). The phase difference meridional winds measured by two MRs located Antarctica gives observational estimates amplitude Q10DW with zonal wavenumber 1 (W1). observed Q10DW-W1...
Abstract Characteristics of inertia‐gravity waves (IGWs) at high latitude in Antarctica are investigated using radiosondes launched daily Jang Bogo Station (74°37′S, 164°13′E), a new Antarctic station that has been operating since 2014, the troposphere ( z = 2–7 km) and lower stratosphere 15–22 for 25 months (December 2014 to December 2016). The vertical propagation IGWs exhibits strong seasonal variations stratosphere, with an enhancement (reduction) downward (upward)‐propagating from May...
Abstract Potential sources of inertia‐gravity waves (IGWs) in the lower stratosphere ( z = 15–22 km) at Jang Bogo Station, Antarctica (74°37′S, 164°13′E) are investigated using 3‐year (December 2014 to November 2017) radiosonde data, including 25‐month result December 2016) analyzed Yoo et al. (2018, https://doi.org/10.1029/2018JD029164 , Part 1). For this investigation, three‐dimensional backward ray tracing calculations conducted Gravity wave Regional Or Global RAy Tracer. Among 248 IGWs,...
Abstract. Residual mean circulation and temperature changes during the evolution of major stratospheric sudden warming (SSW) are investigated by composite analyses 22 SSW events from 1979 to 2012 Northern Hemisphere winter (November–March) using four reanalysis data sets (MERRA, ERA-Interim, NCEP-NCAR, JRA-55). The classified as Type-1 or Type-2 based on relative amplitude planetary waves with zonal wavenumbers 1 2. residual induced each forcing term in Transformed Eulerian (TEM) momentum...
Abstract. Effects of realistic propagation gravity waves (GWs) on distribution GW pseudomomentum fluxes are explored using a global ray-tracing model for the 2009 sudden stratospheric warming (SSW) event. Four-dimensional (4D; x–z and t) two-dimensional (2D; z results compared various parameterized fluxes. In equations, refraction due to horizontal wind shear curvature effects found important comparable one another in magnitude. 4D, westward enhanced upper troposphere northern stratosphere...
Abstract The characteristics of the horizontal wind in mesosphere and lower thermosphere (MLT) at King Sejong Station (KSS) Antarctic Peninsula are investigated using approximately 15‐year (March 2007–November 2021) meteor radar (MR) observations. climatology variability MLT winds KSS analyzed for first time, comparisons with observations other stations performed. short‐period oscillations (periods between 2 hr 10 days) winds, including tides several planetary wave components, examined each...
Abstract We examine the relationships between observed long‐term trends of zonal wind in mesopause regions at King Sejong Station (KSS), Antarctica, and Southern Hemisphere (SH) middle atmosphere using 15‐year data set from KSS meteor radar, Aura MLS MERRA‐2. During July, significant positive winds appear above z = 90 km near stratopause over KSS, while negative exist two layers. In SH winter, correlate positively (negatively) with stratospheric (mesospheric) polar region, they exhibit...
Abstract Contributions of convective gravity waves (CGWs) and orographic (OGWs) to the Brewer–Dobson circulation (BDC) are examined compared those from resolved waves. OGW drag (OGWD) is provided by NCEP Climate Forecast System Reanalysis (CFSR), while CGW (CGWD) obtained an offline calculation a physically based parameterization with heating background data CFSR. CGWD contributes shallow branch BDC regardless season, OGWD both deep branches except for summertime, when OGWs hardly propagate...
Abstract. Effects of realistic propagation gravity waves (GWs) on distribution GW pseudomomentum fluxes (Fps) are explored using a global ray-tracing model for the 2009 sudden stratospheric warming (SSW). Four-dimensional (4D) (x–z, t) and two-dimensional (2D) (z, results compared various parameterized Fps. In equations, refraction due to horizontal wind shear curvature effects found important comparable one another in magnitude. 4D, westward Fps enhanced upper troposphere northern...
Abstract This study presents an analysis of OH airglow images observed from all‐sky camera (ASC) at King Sejong Station (KSS), Antarctic for the 2012–2016 period. The two‐dimensional power spectra short‐period gravity waves (<1 hr) as a function phase velocities are obtained using M‐transform method that employs time sequence ASC images. amplitudes spectral densities show mesospheric wave activity is largest during winter (May, June, and July) smallest in fall (February, March, April)....
Abstract. Seasonal variation of westward-propagating quasi-10-day wave (Q10DW) in the mesosphere and lower thermosphere Southern Hemisphere (SH) high-latitude regions is investigated using meteor radar (MR) observations for period 2012–2016 Specified Dynamics (SD) version Whole Atmosphere Community Climate Model (WACCM). The phase difference meridional winds measured by two MRs located Antarctica gives observational estimates amplitude Q10DW with zonal wavenumber 1 (W1). observed Q10DW-W1...
We analyzed OH airglow images observed from an all-sky camera at King Sejong Station, Antarctica for the period of 2012–2016. Using M-transform method, 2D-power spectra short waves (< 1 hr) were obtained 107 image sequences. The power spectral densities evidently show that mesospheric wave activity is strongest during winter. also constructed climatological wind blocking diagrams using horizontal winds MERRA-2 altitudes = 10–64 km, and KSS meteor radar data 80–90 km. are negatively matched...