# Machine Learning Reconstruction of Wyrtki Jet Seasonal Variability in the Equatorial Indian Ocean
## 3 Results  
### Correlation Analysis Between U and Sea Surface Parameters  
Figure 2 illustrates the monthly satellite-derived sea surface parameters over the equatorial Indian Ocean in February (a1-h1), May (b2-h2), August (c3-h3), and November (d4-h4) of 2022. The parameters included MLD, Curlz, Tx, Ty, SLA, SST, SSS, and D20. Across the entire equatorial region, each parameter exhibits pronounced spatial patterns and heterogeneous characteristics, which vary significantly with seasonal changes. In winter (February), The MLD is shallower near the equator (Figure 2(a1)). The Curlz displays a relatively uniform spatial distribution (Figure 2(b1)). The Tx is predominantly eastward, driven by persistent westerlies associated with the Northeast Monsoon (Figure 2(c1)). The southward Ty is relatively strong during the Northeast Monsoon (Figure 2(d1)). SLA is generally low, indicating a relatively stable ocean state (Figure 2(e1)). SST is higher in the equatorial region (Figure 2(f1)), while SSS is more uniformly distributed, with slightly higher salinity near the equator (Figure 2(g1)). D20 is uniformly distributed in the equatorial region, with an east-west difference of less than 20 m (Figure 2(h1)). In spring (May), the MLD deepens in the eastern region (70\({}^{\circ}\) E-90\({}^{\circ}\) E) (Figure 2(a2)), corresponding to enhanced zonal wind stress (Tx > 0.02 N/m\({}^{2}\)) during the early southwest monsoon (Figure 2(c2)). The negative regions of Curlz expand eastward toward the equator, with locally enhanced negative curl in the western Indian Ocean (50\({}^{\circ}\) E-70\({}^{\circ}\) E) (Figure 2(b2)). The Ty shifts to a northward direction, accompanied by a reversal of cross-equatorial airflow (Figure 2(d2)). SLA rises in the eastern equatorial region due to enhanced westerly wind (Figure 2(e2)). SST exhibits significant warming (29-30 \({}^{\circ}\)C) in the region of 50\({}^{\circ}\) E-75\({}^{\circ}\) E (Figure 2(f2)). The decreases to approximately 35 PSU in the eastern equatorial region,  
Figure 2: Monthly mean spatial distributions of eight variables in (**a1–h1**) February, (**a2–h2**) May, (**a3–h3**) August, and (**a4–h4**) November 2022. Variables include: (**a**) mixed layer depth (MLD), (**b**) wind stress curl (Curlz), (**c**) zonal wind stress (Tx), (**d**) meridional wind stress (Ty), (**e**) sea level anomaly (SLA), (**f**) sea surface temperature (SST), (**g**) sea surface salinity (SSS), and (**h**) depth of the 20 \({}^{\circ}\)C isotherm (D20). while it remains relatively high in the western equatorial region (Figure 2(g2)). The depth of D20 reaches the maximum of \(-\)120 m, accompanied with westerly wind (Figure 2(h2)). In summer (August), the MLD is about 40 m in the central equatorial region, with a slightly deeper mixed layer on the western and eastern equatorial region (Figure 2(a3)). A pronounced negative Curlz region is observed, particularly on the western equatorial region (Figure 2(b3)). The wind stress directions of Tx are opposite north and south of the equator, with positive values in north of the equator and negative values south of the equator (Figure 2(c3)). A positive Ty significantly strengthens west of 70\({}^{\circ}\) E (Figure 2(d3)). SLA on the western side of the equator reaches the maximum (Figure 2(e3)). SST shows significant cooling in the western equatorial region, while the high SST expands on the eastern side (Figure 2(f3)). SSS decreases along the equator (Figure 2(g3)). D20 reaches its maximum in the western equatorial region (Figure 2(h3)). In autumn (November), MLD generally shoals and reaches the minimum in the western equatorial region (Figure 2(a4)). Curlz is positive north of the equator but negative south of equator (Figure 2(b4)). A positive Tx dominates the equator region (Figure 2(c4)), while Ty is relatively weak in the equator region (Figure 2(d4)). SLA strengthens on the eastern side, accompanied by westerly wind (Figure 2(e4)). SST is relatively uniform in the equatorial region (Figure 2(f4)).