Korea’s operational NWP model (KIM) – performance and future plan

Seminar by Dir. Youngcheol Kwon from Numerical modeling center, Korea Meteorological Administration

10 June 2022
KST 15:00 – 16:00

The Seminar is being held in Room 1010 (Jasmin) – Integrated mechanical engineering building. Click here for the campus map.

Korean Integrated Model (KIM) has been an operational global model at Korea Meteorological Administration (KMA) since government funded 9-year project of developing a next generation global model. The main components the model – dynamic core, physics package and data assimilation scheme – are developed from the scratch by Korean Institute of Atmospheric Prediction Systems (KIAPS). The dynamics of KIM includes pressure-sigma hybrid vertical coordinates and spectral-element horizontal discretization over cubed sphere projection. The physics suites are designed to take account the scale-aware capability and inter-scheme consistency. Finally, variational-ensemble hybrid data assimilation system is adopted for KIM.

The anomaly correlation of KIM averaged over Nothern Hemisphere is about 1~2% larger than the current KMA’s operational model (KMA Unified Model, KMA/UM) in terms of 500hPa geopotential height. However, the KIM’s prediction skills of precipitation and typhoons impacted on Korean Peninsular are comparable to KMA/UM. Since KIM’s first operational run at April 28th 00UTC, Numerical Modeling Center of KMA has put great effort to improve the performance of KIM. For example, the recent upgrades of KIM consists of expanding satellite data assimilation and refining lower level physics scheme. The efforts are made especially on reducing the cold bias in the lower-levels of polar regions, which is found to be a major factor of deteriorating forecast accuracy of KIM. The improvements of KIM error after the upgrades are quite large, such as 5% in 500hPa geopotential height and 8% in 850hPa temperature. In this presentation, The overview of KIM including concept of numerical modeling, 2020~2021 KIM performance and KIM upgrade procedures will be presented.