연구보고서
- 저자
- 김무섭 박사
- 작성일
- 2019.06.12
- 조회
- 202
- 요약
- 목차
The APEC Climate Center produces seasonal predictions of prominent climatological variables using a 2.5 degree grid system. However, agriculture and water resource management are concerned with a specific site or a narrow basin, which are only covered roughly with this grid system, and demand daily values for data such as relative humidity, solar radiation, and surface wind speed instead of large-scale circulation variables. These gaps mean that seasonal prediction data is too limited to be used widely and popularly. Therefore, we developed a statistical downscaling method to enhance the utility of the seasonal predictions. Our proposed downscaling method is based on a weather generator called “acidWG,” and it is divided mainly into precipitation and temperature models. The precipitation model consists of several parametric sub-models whose parameters are adjusted for seasonal prediction. The temperature model decomposes the daily variation in the temperature and introduces low-frequency oscillation terms that are simulated and downscaled according to seasonal predictions. Finally, we propose an algorithm for downscaling seasonal prediction based on those models. The proposed method is applied to the Nakdong river basin during MAM and SON to evaluate its performance in terms of reproducibility, validity, and predictability. Results show that the proposed method produces suitable seasonal prediction scenarios.