Fig. 3: Relative contributions of soil moisture-atmosphere coupling (SA) on the seasonal cycle of precipitation and daily-maximum surface air temperature (TX) over tropical land.

a, b Multimodel mean changes (bars), current (solid line), and future climatology (dashed line) of precipitation in the fully coupled experiment (a) and the fixed soil moisture (SM) experiment (b) over northern tropical land (NTL). c SA influence on the seasonal cycle of precipitation calculated by subtracting the values in the fixed soil moisture experiment from those of the fully coupled experiment. d–f As in a–c, but over southern tropical land (STL). g–l As in a–f, but for TX. The ratio values in c, f, i, j indicate the contribution of soil moisture to the seasonal delay (c, f) and the hot-season-gets-hotter phenomenon (i, j) calculated as the local spring changes caused by SA relative to the values in the fully coupled experiment. Error bars represent 25th and 75th percentile of multimodel ensembles. The hatched bars denote significance at the 95% confidence level based on Student’s t test.