Fig. 1
From: Compounding tropical and stratospheric forcing of the record low Antarctic sea-ice in 2016
Observed indices of Antarctic sea-ice and several key climate drivers during austral spring 1979–2017. a Monthly anomaly during 2015–2017 of Antarctic sea-ice extent (SIE) (106 km2). The same time series for full period 1979–2017 is shown in Supplementary Figure 1. b SIE anomaly (106 km2) for September–October (Sep–Oct, red curve) and November–December (Nov–Dec, blue curve); c Sep–Oct SST Niño3.4 index (°C); d Sep–Oct Indian Ocean Dipole Mode index for SST, denoted as SST Dipole Mode Index (SST-DMI, °C); e same as d but the index is calculated using the anomalous OLR, denoted as OLR-DMI (W m−2); f Nov–Dec zonal wind index U60–65S (m s−1). All anomalies are deviations relative to 1979–2015 means. Other details see Methods. Plots were generated using the NCAR Command Language version 6.4.0 (www.ncl.ucar.edu)
