Fig. 3

Linear trends of annual mean ocean potential temperature (units: ℃/100 yr) along the equator (5°S–5°N) during 1981–2010, in observations (a) and CMIP6 multi-model ensemble means (b), CMIP6 S model means (c), CMIP6 W model means (d), and S–W composite differences (e). Dots indicate the trend is statistically significant at the 95% level using Student's t-test; the climatological 20 isotherms are shown for three periods: 1981–1990 (green line),1991–2000 (yellow line), and 2001–2010 (purple lines). f–i, same as b–e, but for the MPI-ESM. j–m, same as b–e, but for the FGOALS-g3