Page 199 - 《高原气象》2026年第2期
P. 199

2 期                       殷齐娥等:基于机器学习的机场低能见度短临预报研究                                         499





                        Nowcasting of Airport Low Visibility Based on Machine Learning



                                             YIN Qi'e , NI Changjian , XIAO An 2, 3
                                                     1, 3
                                                                    1
                       (1. School of Atmospheric Sciences, Chengdu University of Information Technology, Chengdu  610225, Sichuan, China;
                             2. Jiangxi Provincial Key Laboratory of Climate Change Risk and Meteorological Disaster Prevention,
                                                   Nanchang  330096, Jiangxi, China;
                                      3. Jiangxi Meteorological Observatory, Nanchang  330096, Jiangxi, China)

               Abstract: In order to reduce the rate of flight diversion and return caused by low visibility, this study has estab‐
               lished a short-term and nowcasting model of low visibility using ground observation data and the upper-air and
               surface forecast data of the ECMWF at Jingdezhen Airport based on machine learning algorithms. Comparing the
               evaluation indicators, the results find that the XGBoost and LightGBM machine learning algorithms outperform
               the SVM machine learning algorithm in nowcasting of the airport low visibility. A detailed comparison of the
               evaluation  metrics  was  conducted  both  before  and  after  feature  screening  in  the  same  machine  learning  algo‐
               rithms. The study highlights that feature screening significantly boosts the effectiveness of both models. Further‐
               more,  the  SHAP (SHapley Additive  exPlanations)  method  elucidates  the  contribution  of  each  feature  to  the
               LightGBM model's output. The main conclusions are as follows: (1) The machine learning models established
               by  LightGBM  and  XGBoost  perform  well  in  airport  low  visibility  forecasting,  with  the AUC  reaching  up  to
               0. 98, and the F1_score for the prediction of current low visibility and the low visibility in the next one hour can
               reach up to 0. 92.(2)Data cleaning and feature screening is conducive to improving the prediction accuracy of
               the XGBoost algorithm for low visibility in the next hour, according to the principle that "feature engineering in
               machine  learning  requires  features  to  be  mutually  independent". Moreover  the  LightGBM  model  with  feature
               screening has a lower false negative rate than the LightGBM model without feature selection when forecasting
               the current and future one-hour low visibility. For the forecast of the current low visibility, the LightGBM_24_0h
               model is the best. For the forecast of low visibility in the next one hour, the XGBoost_24_1h model is the best.
               And feature selection has a greater improvement on the performance of the XGBoost algorithm.(3) The splitting
               times and SHAP values are used respectively to analyze the feature importance of the LightGBM algorithm mod‐
               el. It shows that under different feature importance criteria, nine features, namely the measured relative humidi‐
               ty, air temperature, wind, sea level pressure at the airport, and the relative humidity at 1000 hPa, vertical veloc‐
               ity and divergence at 925 hPa, and divergence at 850 hPa predicted by ECMWF, are more important for the pre‐
               diction of low visibility at the airport. And divergence, as an input feature of the machine learning model, can
               greatly improve the performance of the machine learning model.(4) When explaining feature importance based
               on SHAP values, the cumulative proportion of the top ten feature importance accounts for 80%. This indicates
               that in the nowcasting of low visibility at Jingdezhen Airport where fog is the main factor, the LightGBM model
               can output prediction results according to key forecast factors,. And when forecasting whether the low visibility
               in  the  next  one  hour  will  continue,  more  attention  should  be  paid  to  the  changes  in  850  hPa  divergence,
               1000 hPa relative humidity, airport sea level pressure and wind direction.
               Key words: airport forecast; low visibility; machine learning; LightGBM
   194   195   196   197   198   199   200   201   202   203   204