Future aridification in terrestrial ecosystems due to ongoing climate change will affect ecosystem structure and functioning. Ecosystems are full of thresholds in their responses to climate and land-use changes as well as in the way their components relate to each other. An ecological research priority is to develop a management scheme that can secure essential ecosystem functioning and services in highly stochastic environments. Recent efforts have identified the climatic thresholds in ecosystem functions and in their relationships to biodiversity in a range of ecosystems. Here, we go beyond current knowledge, exploring climatic thresholds in ecosystem stability and stability-biodiversity relationships across Mongolian grasslands. Ecosystem stability over time is a fundamental property of any ecosystem for the stable provisions of ecosystem services despite variations in environmental conditions and disturbance. Based on the data from 813 sites covering whole Mongolia over 8 consecutive years (2012 to 2019), we detect potential climatic thresholds in the temporal stability of plant productivity, biodiversity, and stability components including species stability and synchrony. We further evaluate how relationships between biodiversity or stability components and temporal stability of productivity shift along extensive climatic gradients across Mongolia.