Description of available datasets

ERA-Interim A Forty-Year European Re-Analysis
(ERA-40)
NCEP/DOE Reanalysis
(Reanalysis-2)
Japanese 25-year ReAnalysis
(JRA-25)
JMA Climate Data Assimilation System
(JCDAS)
Japanese 55-year ReAnalysis
(JRA-55)
NASA's Modern-Era Retrospective Analysis for Research and Applications
(MERRA)
Period Jan. 1, 1979-
Aug. 31, 2017
Sep. 1, 1957-
Aug. 31, 2002
Jan. 1, 1979-
Oct. 31, 2017
Jan. 1, 1979-
Dec. 31, 2004
Jan. 1, 2005-
Nov. 30, 2013
Oct. 1, 1957-
Oct. 31, 2017
Jan. 1, 1979-
Feb. 29, 2016
Frequency 4 times daily (00, 06, 12, 18 UTC) 8 times daily (00, 03, 06, 09, 12, 15, 18, 21 UTC)
Horizontal Resolution 1.5 (degree) x 1.5 (degree) 2.5 (degree) x 2.5 (degree) 1.25 (degree) x 1.25 (degree)
Pressure Levels 37 Levels
(1000, 975, 950, 925, 900, 875, 850, 825, 800, 775, 750, 700, 650, 600, 550, 500, 450, 400, 350, 300, 250, 225, 200, 175, 150, 125, 100, 70, 50, 30, 20, 10, 7, 5, 3, 2, 1 hPa)
23 Levels
(1000, 925, 850, 775, 700, 600, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30, 20, 10, 7, 5, 3, 2, 1 hPa)
17 Levels
(1000, 925, 850, 700, 600, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30, 20, 10 hPa)
22 Levels
(1000, 925, 850, 700, 600, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30, 20, 10, 7, 5, 3, 2, 1 hPa)
37 Levels
(1000, 975, 950, 925, 900, 875, 850, 825, 800, 775, 750, 700, 650, 600, 550, 500, 450, 400, 350, 300, 250, 225, 200, 175, 150, 125, 100, 70, 50, 30, 20, 10, 7, 5, 3, 2, 1 hPa)
42 Levels
(1000, 975, 950, 925, 900, 875, 850, 825, 800, 775, 750, 725, 700, 650, 600, 550, 500, 450, 400, 350, 300, 250, 200, 150, 100, 70, 50, 40, 30, 20, 10, 7, 5, 4, 3, 2, 1, 0.7, 0.5, 0.4, 0.3, 0.1 hPa)