Mechanism of sea-ice expansion in the Indian Ocean sector of Antarctica: Insights from satellite observation and model reanalysis - Fig 4

Depth-Latitude cross section of zonally averaged (20°E to 90°E) trends of potential temperature for (a) summer, (b) autumn, (c) winter, and (d) spring. The trends of ocean current vectors are overlaid as magenta arrows (in figures a-d). Right panel figures indicate the trends of salinity for (e) summer, (f) autumn, (g) winter, and (h) spring. Only the significant trend values (p < 0.05) are considered to plot the figures according to a two-tailed t-test and the dots are marked to show the observations with the significant trends. The contour shows the climatology of temperature (left panel) and salinity (right panel). The data are obtained from the European Centre for Medium-Range Weather Forecast (ECMWF)’s Ocean Reanalysis System 4 (ORAS4) for the period of 1979–2015.