Arid Zone Research ›› 2024, Vol. 41 ›› Issue (4): 527-539.doi: 10.13866/j.azr.2024.04.01

• Weather and Climate • Previous Articles     Next Articles

Prediction of the standardized precipitation evapotranspiration index in the Xinjiang region using the EMD-GWO-LSTM model

XU Chaojie1(), DOU Yan1,2(), MENG Qilin1   

  1. 1. School of Statistics and Data Science, Xinjiang University of Finance and Economics, Urumqi 830012, Xinjiang, China
    2. Xinjiang Social and Economic Statistics and Big Data Application Research Center, Xinjiang University of Finance and Economics, Urumqi 830012, Xinjiang, China
  • Received:2023-07-02 Revised:2024-02-08 Online:2024-04-15 Published:2024-04-26

Abstract:

Drought prediction has always been a major challenge in the field of drought research. Improving the accuracy of drought prediction is the key to solving the drought problem. The standardized precipitation evapotranspiration index (SPEI) was calculated on the basis of the monthly precipitation and average temperature data from 34 meteorological stations in Xinjiang from 1961 to 2019. Dry and wet changes in the Xinjiang region were analyzed. An empirical mode decomposition (EMD)-Gray Wolf Optimizer (GWO)-long short-term memory network is proposed. A combination prediction model based on the data decomposition of LSTM was used to forecast the drought, and the performance of the model was evaluated. The results were as follows: (1) the drought periodicity was stable and the periodicity was long. (2) EMD can effectively optimize the stationarity of data, GWO can optimize the parameters of the prediction model, and the prediction accuracy of the combination model is significantly higher than that of the single prediction model. (3) The accuracy of the results of the four prediction models in descending order was as follows: EMD-GWO-LSTM, GWO-LSTM, GWO-support vector regression (SVR), and LSTM (goodness of fit: 0.972, 0.939, 0.862, 0.830, respectively). The prediction accuracy of the EMD-GWO-LSTM combination prediction model was higher than that of the other three prediction models. The EMD-GWO-LSTM combination prediction model can effectively improve the accuracy of meteorological drought prediction and provide a novel approach for meteorological drought forecasting and drought mitigation in Xinjiang.

Key words: EMD-GWO-LSTM model, standardized precipitation evapotranspiration index, drought prediction, Xinjiang