Multi-Weather Evaluation of Nowcasting Methods Including a New Empirical Blending Scheme
This study utilized a radar echo extrapolation system, a high-resolution numerical model with radar data assimilation, and three blending schemes including a new empirical one, called the extrapolation adjusted by model prediction (ExAMP), to carry out 150 min reflectivity nowcasting experiments for...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2020-10-01
|
| Series: | Atmosphere |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4433/11/11/1166 |
| _version_ | 1827703314412732416 |
|---|---|
| author | Hsin-Hung Lin Chih-Chien Tsai Jia-Chyi Liou Yu-Chun Chen Chung-Yi Lin Lee-Yaw Lin Kao-Shen Chung |
| author_facet | Hsin-Hung Lin Chih-Chien Tsai Jia-Chyi Liou Yu-Chun Chen Chung-Yi Lin Lee-Yaw Lin Kao-Shen Chung |
| author_sort | Hsin-Hung Lin |
| collection | DOAJ |
| description | This study utilized a radar echo extrapolation system, a high-resolution numerical model with radar data assimilation, and three blending schemes including a new empirical one, called the extrapolation adjusted by model prediction (ExAMP), to carry out 150 min reflectivity nowcasting experiments for various heavy rainfall events in Taiwan in 2019. ExAMP features full trust in the pattern of the extrapolated reflectivity with intensity adjustable by numerical model prediction. The spatial performance for two contrasting events shows that the ExAMP scheme outperforms the others for the more accurate prediction of both strengthening and weakening processes. The statistical skill for all the sampled events shows that the nowcasts by ExAMP and the extrapolation system obtain the lowest and second lowest root mean square errors at all the lead time, respectively. In terms of threat scores and bias scores above certain reflectivity thresholds, the ExAMP nowcast may have more grid points of misses for high reflectivity in comparison to extrapolation, but serious overestimation among the points of hits and false alarms is the least likely to happen with the new scheme. Moreover, the event type does not change the performance ranking of the five methods, all of which have the highest predictability for a typhoon event and the lowest for local thunderstorm events. |
| first_indexed | 2024-03-10T15:15:56Z |
| format | Article |
| id | doaj.art-8a78e8565e984b4b9429e655d76b9dc9 |
| institution | Directory Open Access Journal |
| issn | 2073-4433 |
| language | English |
| last_indexed | 2024-03-10T15:15:56Z |
| publishDate | 2020-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj.art-8a78e8565e984b4b9429e655d76b9dc92023-11-20T18:58:10ZengMDPI AGAtmosphere2073-44332020-10-011111116610.3390/atmos11111166Multi-Weather Evaluation of Nowcasting Methods Including a New Empirical Blending SchemeHsin-Hung Lin0Chih-Chien Tsai1Jia-Chyi Liou2Yu-Chun Chen3Chung-Yi Lin4Lee-Yaw Lin5Kao-Shen Chung6National Science and Technology Center for Disaster Reduction, New Taipei City 23143, TaiwanNational Science and Technology Center for Disaster Reduction, New Taipei City 23143, TaiwanNational Science and Technology Center for Disaster Reduction, New Taipei City 23143, TaiwanNational Science and Technology Center for Disaster Reduction, New Taipei City 23143, TaiwanNational Science and Technology Center for Disaster Reduction, New Taipei City 23143, TaiwanNational Science and Technology Center for Disaster Reduction, New Taipei City 23143, TaiwanDepartment of Atmospheric Sciences, National Central University, Taoyuan City 32001, TaiwanThis study utilized a radar echo extrapolation system, a high-resolution numerical model with radar data assimilation, and three blending schemes including a new empirical one, called the extrapolation adjusted by model prediction (ExAMP), to carry out 150 min reflectivity nowcasting experiments for various heavy rainfall events in Taiwan in 2019. ExAMP features full trust in the pattern of the extrapolated reflectivity with intensity adjustable by numerical model prediction. The spatial performance for two contrasting events shows that the ExAMP scheme outperforms the others for the more accurate prediction of both strengthening and weakening processes. The statistical skill for all the sampled events shows that the nowcasts by ExAMP and the extrapolation system obtain the lowest and second lowest root mean square errors at all the lead time, respectively. In terms of threat scores and bias scores above certain reflectivity thresholds, the ExAMP nowcast may have more grid points of misses for high reflectivity in comparison to extrapolation, but serious overestimation among the points of hits and false alarms is the least likely to happen with the new scheme. Moreover, the event type does not change the performance ranking of the five methods, all of which have the highest predictability for a typhoon event and the lowest for local thunderstorm events.https://www.mdpi.com/2073-4433/11/11/1166nowcastingblendingradar echo extrapolationradar data assimilationextrapolation adjusted by model predictionreflectivity |
| spellingShingle | Hsin-Hung Lin Chih-Chien Tsai Jia-Chyi Liou Yu-Chun Chen Chung-Yi Lin Lee-Yaw Lin Kao-Shen Chung Multi-Weather Evaluation of Nowcasting Methods Including a New Empirical Blending Scheme Atmosphere nowcasting blending radar echo extrapolation radar data assimilation extrapolation adjusted by model prediction reflectivity |
| title | Multi-Weather Evaluation of Nowcasting Methods Including a New Empirical Blending Scheme |
| title_full | Multi-Weather Evaluation of Nowcasting Methods Including a New Empirical Blending Scheme |
| title_fullStr | Multi-Weather Evaluation of Nowcasting Methods Including a New Empirical Blending Scheme |
| title_full_unstemmed | Multi-Weather Evaluation of Nowcasting Methods Including a New Empirical Blending Scheme |
| title_short | Multi-Weather Evaluation of Nowcasting Methods Including a New Empirical Blending Scheme |
| title_sort | multi weather evaluation of nowcasting methods including a new empirical blending scheme |
| topic | nowcasting blending radar echo extrapolation radar data assimilation extrapolation adjusted by model prediction reflectivity |
| url | https://www.mdpi.com/2073-4433/11/11/1166 |
| work_keys_str_mv | AT hsinhunglin multiweatherevaluationofnowcastingmethodsincludinganewempiricalblendingscheme AT chihchientsai multiweatherevaluationofnowcastingmethodsincludinganewempiricalblendingscheme AT jiachyiliou multiweatherevaluationofnowcastingmethodsincludinganewempiricalblendingscheme AT yuchunchen multiweatherevaluationofnowcastingmethodsincludinganewempiricalblendingscheme AT chungyilin multiweatherevaluationofnowcastingmethodsincludinganewempiricalblendingscheme AT leeyawlin multiweatherevaluationofnowcastingmethodsincludinganewempiricalblendingscheme AT kaoshenchung multiweatherevaluationofnowcastingmethodsincludinganewempiricalblendingscheme |