Tropical climate variability including the El Niño-Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), and Atlantic Niño/Niña, has long governed global climate interannual fluctuations. Understanding how their influence may change in the next few decades is critically important for climate prediction and adaptation. Here we show that tropical interannual sea surface temperature variability could start to weaken in the next few decades even if greenhouse warming intensifies.