Asian monsoon climate variability at geological time scales is modulated by both the Earth's orbital changes and tectonic uplift of the Tibetan Plateau (TP). Here, using bandpass-filtered versions of previously-published high-resolution geological records from Chinese loess, we show that the orbital-scale variability of the East Asian summer monsoon (EASM) has increased dramatically since the late Pliocene. Climate model simulations indicate that the increase in the variability of the northern EASM at both precession and tilt periods may be, at least partially, attributed to the uplift of the TP.