A5000888223- Atmospheric chemistry and aerosols
- Atmospheric aerosols and clouds
- Climate variability and models
- Atmospheric Ozone and Climate
- Meteorological Phenomena and Simulations
- Atmospheric and Environmental Gas Dynamics
- Arctic and Antarctic ice dynamics
- Cryospheric studies and observations
- Air Quality and Health Impacts
- Air Quality Monitoring and Forecasting
- Tropical and Extratropical Cyclones Research
- Plant Water Relations and Carbon Dynamics
- Oceanographic and Atmospheric Processes
- Marine and Coastal Research
- Urban Heat Island Mitigation
- Climate change and permafrost
- Precipitation Measurement and Analysis
- Diverse Approaches in Healthcare and Education Studies
- Remote Sensing in Agriculture
- Remote Sensing and Land Use
- Fire effects on ecosystems
- Energy and Environment Impacts
- Aeolian processes and effects
- Ocean Waves and Remote Sensing
- Solar Radiation and Photovoltaics
Ewha Womans University Medical Center
2011-2025
Ewha Womans University
2015-2024
Hongik University
2024
Jet Propulsion Laboratory
2016-2018
California Institute of Technology
2018
Samsung (South Korea)
2011
Massachusetts Institute of Technology
2009-2010
Seoul National University
2005-2009
Pukyong National University
2006
The Geostationary Environment Monitoring Spectrometer (GEMS) is scheduled for launch in February 2020 to monitor air quality (AQ) at an unprecedented spatial and temporal resolution from a geostationary Earth orbit (GEO) the first time. With development of UV–visible spectrometers sub-nm spectral sophisticated retrieval algorithms, estimates column amounts atmospheric pollutants (O3, NO2, SO2, HCHO, CHOCHO, aerosols) can be obtained. To date, all satellite missions monitoring have been low...
This study examines the vertically resolved cloud measurements from cloud-aerosol lidar with orthogonal polarization instrument on Aqua satellite June 2006 through May 2007 to estimate extent which mixed cloud-phase composition can vary according ambient temperature, an important concern for uncertainty in calculating radiative effects. At -20 degrees C, global average fraction of supercooled clouds total population is found be about 50% data period. Between -10 and -40 smaller at lower...
Abstract The change of global-mean precipitation under global warming and interannual variability is predominantly controlled by the atmospheric longwave radiative cooling. Here we show that tightening ascending branch Hadley Circulation coupled with a decrease in tropical high cloud fraction key modulating response to surface warming. magnitude shrinkage primary contributor intermodel spread changes tropical-mean outgoing radiation (OLR) per unit (d P/ d T s ) for both Compared...
Abstract Previous laboratory studies and in situ measurements have shown that dust particles possess the ability to nucleate ice crystals, smoke some extent as well. Even with coatings of pollutants such sulphate nitrate on surface particles, it has been polluted are still able immersion, deposition, condensation, contact freezing modes, albeit less efficiently than unpolluted dust. The these aerosols act nuclei Earth's atmosphere important implications for radiative budget hence global...
Abstract. The Geostationary Environment Monitoring Spectrometer (GEMS) on board GEO-KOMPSAT-2B was launched in February 2020 and has been monitoring atmospheric chemical compositions over Asia. We present the first evaluation of operational GEMS formaldehyde (HCHO) vertical column densities (VCDs) during after in-orbit test (IOT) period (August–October 2020) by comparing them with products from TROPOspheric Instrument (TROPOMI) Fourier-transform infrared (FTIR) multi-axis differential...
Abstract. This paper introduces a cloud retrieval algorithm for the Geostationary Environmental Monitoring Spectrometer (GEMS), first environmental geostationary orbit satellite, and validates its products by comparing them with those produced other instruments (OMI, TROPOMI, AMI, CALIOP). The GEMS are corrected impact of clouds on atmospheric components using O2–O2 absorption band to retrieve effective fraction centroid pressure. performance was similar that OMI. We analyzed characteristics...
Climate feedbacks are estimated from fluctuations in the outgoing radiation budget latest version of Earth Radiation Budget Experiment (ERBE) nonscanner data. It appears, for entire tropics, observed fluxes increase with sea surface temperatures (SSTs). The behavior implies negative feedback processes associated relatively low climate sensitivity. This is opposite 11 atmospheric models forced by same SSTs. Therefore, display much higher sensitivity than inferred ERBE, though it difficult to...
[1] This study investigates the changes in winter cold extreme events over East Asia present and future climates. Two distinct terms to indicate are analyzed: "cold day," which describes a temperature below certain threshold value (e.g., simply weather), surge," an abrupt drop relatively colder weather than previous day). We analyze both observations long-term climate simulations from 13 atmospheric oceanic coupled global models (CGCMs). The geographical distribution of sea level pressure...
Abstract The ratio of liquid water to ice in a cloud, largely controlled by the presence nuclei and cloud temperature, alters radiative effects. This study quantitatively examines how fraction clouds influences various climate feedbacks using NCAR Community Atmosphere Model (CAM). Climate feedback parameters were calculated equilibrated temperature changes response increases atmospheric concentration carbon dioxide CAM Version 3.0 with slab ocean model. Two sets model experiments are...
ABSTRACT This study investigates the origin of interdecadal variability in warm Arctic and cold Eurasia (WACE) pattern, which is defined as second empirical orthogonal function surface air temperature (SAT) over Eurasian continent Northern Hemisphere winter, by analyzing Twentieth Century Reanalysis dataset. While previous studies highlight recent enhancement WACE ascribing it to anthropogenic warming, authors found that pattern has experienced a seemingly periodic variation twentieth...
Among models participating in the Coupled Model Intercomparison Project phase 6 (CMIP6), here we show that magnitude of tropical low cloud feedback, which contributes considerably to uncertainty estimates climate sensitivity, is intimately linked deep convection and its effects on atmospheric overturning circulation. First, a reduction ascent area an increased frequency heavy precipitation result high upper-tropospheric drying, increases longwave cooling reduces subsidence weakening,...
The charge pump (CP) circuit is a key element in phase-locked loop (PLL). Its function to transform the Up and Down signals from phase/frequency detector into current. In CMOS CPs, which have switches made of p-channel MOS n-channel MOS, respectively, current mismatch occurs when dumping filter. This CP PLL generates fluctuations voltage-controlled-oscillator input subsequently, large phase noise on output signals. this brief, new with good matching characteristics proposed. By using simple...
Abstract The authors investigate the short-term relationship between aerosol concentrations and summer rainfall frequency in China using daily surface observations of particulate matters with a diameter less than 10 μm (PM10) mass concentration, rainfall, satellite-observed cloud properties. Results this study reveal that on time scale few days concentration is positively correlated moderate-rainfall (10–20 mm day−1) but negatively light-rainfall (<5 days. Satellite properties show...
Abstract This study demonstrates that absorbed solar radiation (ASR) at the top of atmosphere in early summer (May–July) plays a precursory role determining Arctic sea ice concentration (SIC) late (August–October). The monthly ASR anomalies are obtained over Ocean (65°N–90°N) from Clouds and Earth's Radiant Energy System during 2000–2013. changes primarily with cloud variation. We found anomaly is significantly correlated SIC (correlation coefficient, r ≈ −0.8 lag 1 to 4 months). region...
Abstract. Optimization of land surface models has been challenging due to the model complexity and uncertainty. In this study, we performed scheme-based optimizations by designing a framework for coupling "the micro-genetic algorithm" (micro-GA) Noah with multiple physics options" (Noah-MP). Micro-GA controls scheme selections among eight different parameterization categories, each containing 2–4 schemes, in Noah-MP order extract optimal combination that achieves best skill score. This was...
Abstract Two dominant global-scale teleconnections in the Northern Hemisphere (NH) extratropics during boreal summer season (June–August) have been identified: western North Pacific–North America (WPNA) and circumglobal teleconnection (CGT) patterns. These patterns are of critical importance for NH seasonal climate prediction. Here, how these will change under anthropogenic global warming is investigated using representative concentration pathway 4.5 (RCP4.5) experiments by 20 coupled models...
Abstract Forecasting rapid intensification (RI) of tropical cyclones (TC) is a mission known for large errors. One under-researched factor that affects TC salinity, which important density stratification in certain ocean regions and can affect the surface enthalpy flux under strengthening hurricane. To investigate impact efficacy using salinity information state-of-the-art forecasting, we use statistical model consisting variety machine learning (ML) methods. For data, satellite measurements...
<title>Abstract</title> Wildfires have caused significant damage to the economy, human health, and ecosystems over extended periods. Satellites offer advantages as wildfire detection tools because they provide near real-time, continuous observations in areas that are difficult manage directly by humans. But previous studies, satellite active products were prone generating false alarms with high reflectance, such bare soils, urban regions, water bodies, clouds. This issue arises infrared...
The radiative effects of cirrus clouds are evaluated based on observations extending over a period six years (2000–2005) from the Moderate Resolution Imaging Spectroradiometer (MODIS) and Clouds Earth's Radiant Energy System (CERES) Tropics (25°S–25°N). cloud effect (CRE) shows positive sign for optically thin (total‐column optical depth: τ < 10) negative thicker ( ≥ 10), regardless region season. Since considerable portion tropical ice consists in (>60%), their net effective CRE (net...