The properties of turbulent lifted non-premixed hydrogen jet flames under different coflow air temperature have been analyzed due to their relevance to practical applications. Three dimensional direct numerical simulations of turbulent lifted hydrogen/air jet flames were conducted to examine the flame structure and stabilization mechanisms of turbulent lifted jet flames. Chemical explosive mode analysis (CEMA) reveals the important variables and reactions for stabilizing the lifted flames. The high coflow air temperature DNS case shows that auto ignition is the main source of stabilization mechanism of the lifted flame. On the other hand, the case of low coflow air temperature indicates that flame propagation is the dominant stabilization mechanism of lifted jet flame.