An examination of potential seasonal predictability in recent reanalyses

This study examined potential seasonal predictability of precipitation and 2‐m temperature in the recent global reanalyses from 1979 to 2012. The reanalyses being investigated are R1 , R2 , ERA ‐40, JRA25 , ERA ‐I, MERRA , CFSR and 20CR . When compared against Global Precipitation Climatology Project ( GPCP ) precipitation, ERA ‐I and CFSR provide the best estimates of potential predictability, MERRA , R1 and R2 overestimate predictability and ERA ‐40 and JRA25 are unrealistic in the tropics. Predictability estimates of 2‐m temperature from 20CR , JRA25 , R1 , MERRA , CFSR and R2 exhibit better agreement with the reanalysis ensemble mean than ERA ‐40 and ERA ‐I, which identify less predictability .