Extended Data Figure 9. 1970-2018 trends in summer pycnocline stratification and mixed layer depth when only using ship-based profiles (removing all Argo and MEOP program observations).
(a) Map of the 1970-2018 summer pycnocline stratification trend (i.e. N2 trend in s-2 dec-1), along with zonal-median value: median in bold black, and 33-66 percentile in thin black. The red shading shows the global 33-66 percentile range of the local trend estimates. Regions with no significant trend (see Methods) are shaded in gray on the map. (c, d) same as panel (a,b) but for summer mixed layer trend in m dec-1 (note that mixed layer deepening is shown as a negative trend).