Fig. 4: Atmosphere and ocean variability during low Antarctic sea ice events for SPEAR_LO control simulation.
From: Antarctic sea ice multidecadal variability triggered by Southern Annular Mode and deep convection
a Lead/lag composite anomalies of Antarctic SIE (black in 106 km2), Southern Ocean (south of 60°S) zonal (red in 10−3 Pa) and meridional (blue in 10−4 Pa) wind stress, and wind stress curl (light blue in 10−9 Pa m−1) during the low Antarctic sea ice events for the SPEAR_LO CTL simulation. Anomalies are smoothed with a 15-yr running mean filter. Positive (negative) lead/lag years mean that Antarctic SIE leads (lags) the other variables. Thick lines indicate significant anomalies exceeding 95% confidence level using a Student’s t-test. b Same as in (a), but for the net surface heat flux (Total; black in W m−2) and contributions from latent heat flux (red), sensible heat flux (blue), longwave radiation (light blue), and shortwave radiation (orange). Positive values indicate more downward heat flux into the ocean. c Same as in (a), but for Antarctic SIE (black in 106 km2), SAM (red in 10−1 Pa) and IPO (blue in 2 × 10−2 °C) indices. d Same as in (a), but for Antarctic SIE (black in 106 km2), SST (red in 10−1 °C), sea surface salinity (SSS; blue in 10−1 PSU), mixed-layer depth (MLD; purple in 101 m), Southern Ocean deep convection (SODC; light blue in Sv), and the upper 1000-m available potential energy (APE; orange in 101 J m−3). e Same as in (a), but for the upper 200-m ocean temperature tendency (Total; black in 10−1 W m−2) and contributions from horizontal (Adv_xy; red) and vertical (Adv_z; blue) advection, surface boundary forcing (Sbfc; light blue), and mesoscale diffusion and dianeutral mixing (Difmix; orange). f Same as in (e), but for the upper 200-m ocean salinity tendency (Total; black in 10−7 kg m−2 s−1) and contributions from horizontal (Adv_xy; red) and vertical (Adv_z; blue) advection, surface boundary forcing (Sbfc; light blue), and mesoscale diffusion and dianeutral mixing (Difmix; orange).
