• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
• /
• 2011.11a
• /
• pp.37-38
• /
• 2011

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
• /
• 2012.07a
• /
• pp.59-61
• /
• 2012

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
• /
• 2013.11a
• /
• pp.73-78
• /
• 2013

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
• /
• 2016.09a
• /
• pp.54-59
• /
• 2016

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.6 no.4
• /
• pp.272-289
• /
• 2004

The spatial resolution of local weather and climate information for agronomic practices exceeds the current weather service scale. To supplement the insufficient spatial resolution of official forecasts and observations, gridded climate data are frequently generated. Most ecological models can be run using gridded climate data to produce ecosystem responses at landscape scales. In this lecture, state of the art techniques derived from geospatial climatology, which can generate gridded climate data by spatially interpolating point observations at synoptic weather stations, will be introduced. Removal of the urban effects embedded in the interpolated surfaces of daily minimum temperature, incorporation of local geographic potential for cold air accumulation into the minimum temperature interpolation scheme, and solar irradiance correction for daytime hourly temperature estimation are presented. Some experiences obtained from their application to real landscapes will be described.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.16 no.3
• /
• pp.246-260
• /
• 2014

A 90-m horizontal-resolution numerical model was configured to study the micrometeorological features of local winds in the valley of Gwangneung KoFlux (Korea Flux network) Sites (GDK: Gwangneung Deciduous forest site in Korea, GCK: Gwangneung Coniferous forest site in Korea) during summer days. The U. S. Geological Survey (USGS) Shuttle Radar Topography Mission (SRTM) data were employed for high-resolution model terrain height. Model performance was evaluated by comparing observed and simulated near-surface temperature and winds. Detailed qualitative analysis of the model-simulated wind field was carried out for two selected cases which are a clear day (Case I) and a cloudy day (Case II). Observed winds exhibited that GDK and GCK, as well as Case I and Case II, had differences in timing, duration and strength of daytime and nighttime wind direction and speeds. The model simulation results strongly supported the existence of the drainage flow in the valley of the KoFlux tower sites. Overall, the simulated model fields realistically presented the diurnal cycle of local winds in and around the valley, including the morning drainage-upslope transition and the evening reversal of upslope wind. Also, they indicated the complexity of local winds interactions by presenting that daytime westerly winds in the valley were not always pure mountain winds and were often coupled with larger-scale wind systems, such as synoptic-scale winds or mesoscale sea breezes blowing from the west coast of the peninsula.

• Journal of Environmental Impact Assessment
• /
• v.20 no.4
• /
• pp.539-555
• /
• 2011

Newly constructed, high-rise dense building areas by urban development can cause changes in local wind fields. Wind fields were analyzed to assess the impact on the local meteorology due to the land use changes during the urban redevelopment called "Eunpyeong new town" in north-western Seoul using CFD_NIMR_SNU (Computational Fluid Dynamics, National Institute of Meteorological Research, Seoul National University) model. Initial value of wind speed and direction use analysis value of AWS (Automatic Weather Station) data during 5 years. In the case of the pre-construction with low rise built-up area, it was simulated that the spatial distribution of horizontal wind fields depends on the topography and wind direction of initial inflow. But, in the case of the post-construction with high rise built-up area, it was analyzed that the wind field was affected by high rise buildings as well as terrain. High-rise buildings can generate new circulations among buildings. In addition, small size vortexes were newly generated by terrain and high rise buildings after the construction. As high-rise buildings act as a barrier, we found that the horizontal wind flow was separated and wind speed was reduced behind the buildings. CFD_NIMR_SNU was able to analyze the impact of high-rise buildings during the urban development. With the support of high power computing, it will be more common to utilize sophisticated numerical analysis models such as CFD_NIMR_SNU in evaluating the impact of urban development on wind flow or channel.

• The Bulletin of The Korean Astronomical Society
• /
• v.19
• /
• pp.11.1-11.1
• /
• 1994

• Atmosphere
• /
• v.29 no.5
• /
• pp.525-535
• /
• 2019

Vertical distributions of aerosol mass concentrations over Seoul and Gangneung from January to February 2015 were investigated using aerosol Mie-scattering lidars. Vertical mass concentration of aerosol was calculated from the lidar data using KALION's algorithm and quantitatively compared with ground PM₁₀ concentration to obtain objectivity of data. The backward trajectories calculated using HYSPLIT (version 4) were clustered into 5 traces for Seoul and 6 traces for Gangneung, and the observed aerosol vertical mass distribution was analyzed for individual trajectories. Result from the analysis shows that, aerosol concentrations with in the planetary boundary layer were highest when airflows into the measurement points originated in the Shandong Peninsula or the Inner Mongolia. In addition, the difference of aerosol mass concentrations in the two regions below 1 km was about twice as large as that in the long range transport from the Shandong Peninsula compared to the local emission. This result shows that the air quality over Korea related to particulate matters are affected more by aerosol emissions in the upstream source regions and the associated transboundary transports than local emissions. This study also suggests that the use of local aerosol observations is critical for accurate simulations of aerosol-cloud interactions.

• Atmosphere
• /
• v.24 no.1
• /
• pp.69-76
• /
• 2014

Urbanization affects the local thermal environment due to the large scale land use changes. To investigate the weather environment change of large scale urban redevelopment, 9 surface temperature and humidity observations were accomplished at Eunpyeong new town area. The observation period is from March 2007 to February 2010. In the center of development area, the air temperature has increased and relative humidity has decreased, by the changes of the land cover and building construction. In the area where the green zone is maintained, air temperature and relative humidity were not changed significantly. The air temperature and relative humidity for the other development observation stations is decreased and increased, respectively. The relative temperature difference between study area and a neighboring rural location was increased during observation periods. The difference is the highest during winter. The urban-rural minimum temperature difference was increased at development area, which means that urbanization affects increasing of minimum temperature in study area.