## 3 Results and Discussion
### CEJ Occurrences Based on Local Times, Solar Activity Levels, and Seasons
Meanwhile, in the African sector, such asymmetry was attributed to differences in meridional currents across different longitudes [8] as the direction of the meridional current varies significantly with longitude, local time, and season [26]. However, this might have less relevance in corroborating our results since we adopted data from the insular and peninsular regions of Southeast Asia. Meanwhile, in the Indian sector [16], the divergence in CEJ occurrence between the mainland and insular regions, which are separated by \(\sim\)15\({}^{\circ}\), was related to local effects associated with eastward zonal winds influence [27], gravity wave atmospheric tidal interactions [28; 29], and returning of westward currents due to atmospheric tidal effects [30; 31]. Although these aforementioned mechanisms could possibly explain the asymmetry seen in the current work, a detailed investigation into its relevance, particularly in Southeast Asia, is required in a separate study. Figures 5 and 6 present the seasonal variation of CEJ types in the east and west, respectively. Each figure was complemented with its annual rate that was estimated according to season--Equinox (March-May, September-November), June solstice (June-August), and December solstice (December-February) [32; 33] in subplots (a) and (d). Also included are a series of pie charts to represent season dominancy at different solar activity levels. The results shown in these figures were supported with a monthly rate plot in Figure 7.  
In Figure 5a, the percentage of MCEJ in the east was prominent during Equinox. The seasonal pattern was anticorrelated with F10.7 index as poor correlation value was obtained. Equinox accounted for 71% of MCEJ occurrences at both levels from the pie charts (b) and (c), with D-solstice and J-solstice accounting for 29%. Similarly, the ACEJ seasonal pattern in (d) disagreed with the F10.7 index, associated with zero occurrences at the highest F10.7 index (2014). At a low level (refer to (e)), the percentage accounting for Equinox was counterpart with D-solstice and remained 18% for J-solstice, which contradicted the high solar activity level in (f) wherein 59% of the occurrence was dominated by J-solstice. The dominancy of this ACEJ during J-solstice, together with the prominent occurrence of MCEJ during Equinox seasons for high solar activity level, can be clearly observed in the CEJ monthly rate plot, as presented in Figure 7.  
Figure 5: Seasonal variation (left y-axis) of (**a**) MCEJ and (**d**) ACEJ in the east (DAV) alongside F10.7 index (right y-axis), throughout the solar cycle 24, accompanied with its dominance at (**b**,**e**) low and (**c**,**f**) high solar activity levels. Figure 6 presents results from LKW station, where a comparable percentage of MCEJ between the west and east was obtained in (a), regardless of seasons. A slight ACEJ correlation between occurrence during J-solstice season and the F10.7 index (R = 0.67) could be seen in (d). At different solar activity levels, the ACEJ percentage accounting for Equinox in (e) was initially equivalent to J-solstice, before dominating the high level in (f). Similarly  
Figure 6: Seasonal variation (left \(y\)-axis) of (**a**) MCEJ and (**d**) ACEJ in the west (LKW) alongside F10.7 index (right \(y\)-axis), throughout the solar cycle 24, accompanied with its dominance at (**b**,**e**) low and (**c**,**f**) high solar activity levels. Figure 7: Monthly rate of MCEJ and ACEJ at during high solar activity level in the east (DAV) and west (LKW) sides. to the east, this prominent observation of ACEJ during J-solstice was confirmed by the CEJ monthly rate, as illustrated in Figure 7.  
It was evident that the pronounced seasonal variation of CEJ at different solar activity levels exhibited east-west symmetrical behavior during Equinox season for the greatest MCEJ occurrence and J-solstice at high solar activity level for ACEJ.