Regional high spatial and temporal resolution ionospheric TEC map reconstruction base on DCT-PLS algorithm

Ionospheric TEC map with high temporal and spatial resolution plays an important role for the analysis and modeling of small and medium scale ionospheric disturbances. Based on the monitoring data of the crustal movement observation network of China(CMONOC) and the IGS, the reconstruction of high spatial and temporal resolution TEC maps (1°×1°×15 min) in China and its surrounding areas is realized based on penalized least square regression and discrete cosine transform (DCT-PLS) algorithm. The results are compared with the data of MIT Madrigal high precision vertical TEC data in 2014 and 2018. Compared with GIM data from CODE, the consistency and stability of vertical TEC given by DCT-PLS algorithm is obviously improved. The average error of TEC is reduced from 3.9 TECU to 2.0 TECU, and the standard deviation is reduced from 3.7 TECU to 2.7 TECU. The results of ionospheric reconstruction during a magnetic storm in September 2017 show that this algorithm can better reproduce the ionospheric disturbance structure characteristics during the magnetic storm, and the related results can provide theoretical support for the realization of regional high-resolution ionospheric monitoring and application.