Abstract. To improve our knowledge of urban meteorology, including those processes applicable to high-resolution meteorological models in the Seoul Metropolitan Area (SMA), the Weather Information Service Engine (WISE) Urban Meteorological Observation System (UMS-Seoul) has been designed and installed. The UMS-Seoul incorporates 14 surface energy balance (EB) systems, 7 surface-based threedimensional (3-D) meteorological observation systems and applied meteorological (AP) observation systems, and the existing surface-based meteorological observation network. The EB system consists of a radiation balance system, sonic anemometers, infrared CO 2 /H 2 O gas analyzers, and many sensors measuring the wind speed and direction, temperature and humidity, precipitation, and air pressure. The EBproduced radiation, meteorological, and turbulence data will be used to quantify the surface EB according to land use and to improve the boundary-layer and surface processes in meteorological models. The 3-D system, composed of a wind lidar, microwave radiometer, aerosol lidar, or ceilometer, produces the cloud height, vertical profiles of backscatter by aerosols, wind speed and direction, temperature, humidity, and liquid water content. It will be used for highresolution reanalysis data based on observations and for the improvement of the boundary-layer, radiation, and microphysics processes in meteorological models. The AP system includes road weather information, mosquito activity, water quality, and agrometeorological observation instruments. The standardized metadata for networks and stations are documented and renewed periodically to provide a detailed observation environment. The UMS-Seoul data are designed to support real-time acquisition and display and automatically quality check within 10 min from observation. After the quality check, data can be distributed to relevant potential users such as researchers and policy makers. Finally, two case studies demonstrate that the observed data have a great potential to help to understand the boundary-layer structures more deeply, improve the performance of high-resolution meteorological models, and provide useful information customized based on the user demands in the SMA.

Abstract. To improve our knowledge of urban meteorology, including those processes applicable to high-resolution meteorological models in the Seoul Metropolitan Area, a Weather Information Service Engine urban meteorological observation system network (UMS-Seoul) has been designed and installed. The network incorporates 14 surface energy balance (EB) systems, 7 surface-based 3-dimensional meteorological observation (3D) systems, and applied meteorological observation (AP) systems, as well as the existing surface-based meteorological observation network. The EB system consists of a radiation balance system, sonic anemometers, infrared CO2/H2O gas analyzers, and many sensors to measure wind speed and direction, temperature and humidity, precipitation, and air pressure, etc. The EB-produced radiation, meteorological, and turbulence data will be used to quantify the surface energy balance according to land use, and improve the boundary layer and surface processes in meteorological models. The 3D system, composed of wind lidar, a microwave radiometer, an aerosol lidar, or a ceilometer, produces vertical profiles of backscatter by aerosols or water vapor, cloud height, wind speed and direction, temperature, humidity, and liquid water content. It will be used for high-resolution reanalysis data based on observations as well as for improvement of the boundary layer, radiation, and microphysics processes in meteorological models. The AP system includes road weather information, mosquito activity, and water quality observation instruments. The standardized metadata for networks and stations are documented and renewed periodically to provide a detailed observation environment. The UMS-Seoul data are designed to support real-time acquisition, as well as display and automatically quality check the data within 10 minutes of observation. After the quality check, data can be distributed to relevant potential users such as researchers and policy makers.

The metadata for urban meteorological observation is standardized through comparison with those established at the World Meteorological Organization and the Korea Meteorological Administration to understand the surrounding environment around the sites exactly and maintain the networks and sites efficiently. It categorizes into metadata for an observational network and observational sites. The latter is again divided into the metadata for station general information, local scale information, micro scale information, and visual information in order to explain urban environment in detail. The metadata also contains the static information such as urban structure, surface cover, metabolism, communication, building density, roof type, moisture/heat sources, and traffic as well as the update information on the environment change, maintenance, replacement, and/or calibration of sensors. The standardized metadata for urban meteorological observation is applied to the Weather Information Service Engine (WISE) integrated meteorological sensor network and sites installed at Incheon area. It will be very useful for site manager as well as researchers in fields of urban meteorology, radiation, surface energy balance, anthropogenic heat, turbulence, heat storage, and boundary layer processes.

<p>The planetary boundary layer (PBL) is the lowest part of the atmosphere and it is directly influenced by its contact with a planetary surface and the PBL height (PBLH) varies with time, season and topography. In this study, PBLH is estimated from atmospheric profiles utilizing the parcel method, the bulk Richardson method and the temperature inversion method using the potential temperature, turbulence and temperature gradients, respectively. Additionally, the theta gradient profile and the mixing ratio gradient profile are used to estimate PBL discontinuity in the previous methods. The ERA5 reanalysis is used as reference data in order to develop the PBLH estimation algorithm. During the day, the PBLH is first estimated by the parcel method. If the estimated PBLH is less than 3000 m, it is final PBLH. If not, secondly, calculate the bulk Richardson number to find the height below criteria (0.25) as the final PBLH. When these conditions are not satisfied, finally, the height of the maximum theta gradient subtracts the difference between the height obtained from the bulk Richardson number and the height of the maximum theta gradient. These differences are hourly averaged over the duration of the study. During the nighttime (from evening to morning), PBLH is estimated by the temperature inversion method, and if it greater than 1500 m or not calculated, PBLH is calculated using the theta gradient method and the mixing ratio gradient method. The algorithm is applied to Ground-based microwave radiometer (MWR) profiles, the one-dimensional variational (1D-VAR) retrieval profiles based on the optimal estimation by combining MWR brightness temperatures and a priori information from Local Data Assimilation and Prediction System model. The PBLH difference between MWR and ERA5 shows a large correlation coefficient (0.59) than between 1D-VAR and ERA5. On contrary, the statistical error of 1D-VAR is lower than MWR. Compared to MWR, The RMSE is reduced to 12 % and bias is reduced to 82.5 %. Detailed methods and results in this study will be presented at the conference.</p>