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. 2023 Sep 27;623(7985):83–89. doi: 10.1038/s41586-023-06544-0

Fig. 3. Observed and simulated changes in the seasonal cycle of oceanic conditions.

Fig. 3

Observed results (OBS) obtained from the ECMWF and ERA-5 datasets, results from the multimodel mean of CMIP6 historical (HIS) simulations and results from the multimodel mean of simulations forced by GHG only are shown. a,b, The climatological mean value of PI (solid lines) and the linear trend of the fractional area covered by high PI (bars) (‘Environmental factors’) in each month during the active season during 1981–2017 in the NH (a) and the SH (b). The calculation of PI is based on the oceanic variables from the ECMWF dataset and the atmospheric variables from the ERA-5 dataset. The error bars represent the 95% confidence intervals in the linear regression analysis. c,d, The climatological mean value of OHC (solid lines) and the linear trend of the fractional area covered by high OHC (bars) (‘Environmental factors’) obtained from the ECMWF dataset in each month during the active season during 1981–2017 in the NH (c) and the SH (d). e–h, Same as in a–d but obtained from the HIS simulations. The climatological mean value of PI (solid lines) and the linear trend of the fractional area covered by high PI (bars) (‘Environmental factors’) in each month during the active season during 1981–2017 in the NH (e) and the SH (f). The climatological mean value of OHC (solid lines) and the linear trend of the fractional area covered by high OHC (bars) (‘Environmental factors’) in each month during the active season during 1981–2017 in the NH (g) and the SH (h). The error bars indicate the s.d. i–l, Same as in a–d but obtained from the GHG simulations. The climatological mean value of PI (solid lines) and the linear trend of the fractional area covered by high PI (bars) (‘Environmental factors’) in each month during the active season during 1981–2017 in the NH (i) and the SH (j). The climatological mean value of OHC (solid lines) and the linear trend of the fractional area covered by high OHC (bars) (‘Environmental factors’) in each month during the active season during 1981–2017 in the NH (k) and the SH (l).  On the x axis, −1 indicates the previous year and 0 indicates the current year.