Ensuring resilience against environmental variations is becoming one of the great challenges of chip design. In this paper, we propose a self adjusting clock tree architecture, SACTA, to improve chip performance and reliability in the presence of on-chip temperature variations. SACTA performs temperature dependent dynamic clock skew scheduling to prevent timing violations in a pipelined circuit. We present an automatic temperature adjustable skew buffer design, which enables the adaptive feature of SACTA. Furthermore, we propose an efficient and general optimization framework to determine the configuration of these special delay elements. Experimental results show that a pipeline supported by SACTA is able to prevent thermal induced timing violations within a significantly larger range of operating temperatures (enhancing the violation-free range by as much as 45°C).