How can I solve this problem in EnergyPlus when I do the simulation?

Program Version,EnergyPlus, Version 8.4.0-832e4bb9cb, YMD=2015.12.02 09:25,IDD_Version 8.4.0
   ** Warning ** GetHTSurfaceData: Surfaces with interface to Ground found but no "Ground Temperatures" were input.
   **   ~~~   ** Found first in surface=A84D86
   **   ~~~   ** Defaults, constant throughout the year of (18.0) will be used.

How how can I solve this problem in EnergyPlus when I do the simulation?

Program Version,EnergyPlus, Version 8.4.0-832e4bb9cb, YMD=2015.12.02 09:25,IDD_Version 8.4.0
   ** * Warning ** * GetHTSurfaceData: Surfaces with interface to Ground found but no "Ground Temperatures" were input.
   ** *   ~~~   ** * Found first in surface=A84D86
   ** *   ~~~   ** * Defaults, constant throughout the year of (18.0) will be used.