Datasets	Areal Coverage	Grid Size	Time Step	Time Coverage	Levels
CRU Air Temperature and Combined Air Temperature/Marine Anomalies V4	Global	5.0°x5.0°	Monthly	1850-2013	None
GHCN Version 3 Land Temperature Dataset	Global	5.0°x5.0°	Monthly	1900-present	None
NOAA GHCN_CAMS Land Temperature Analysis	Global	0.5°x0.5°	Monthly	1948-present	None
GISS surface temperature analysis	Global	1.0°x1.0°	Monthly	1880-present	None
NCEP GODAS ocean analysis	Global	.3°x.3°	Monthly	1980-present	40
ICOADS	Global	2.0°x2.0°,1.0°x1.0°	Monthly	1800-present	None
Livneh daily CONUS near-surface gridded meteorological and derived hydrometeorological data.	CONUS	0.06°x0.06°	Daily, Monthly	1915-2011	None
NCEP Operational Analysis	Global	2.5°x2.5°	Daily	1979-present	None
NCEP Marine	Global	2.0°x2.0°	Monthly	1991-present	None
NCEP/NCAR Reanalysis	Global	2.5°x2.5°, T42 Gaussian, T62 spectral	4X Daily, Daily, Monthly	1948-present	17 pressure levels, 28 spectral
NCEP/NCAR Reanalysis Products Derived at NOAA/PSL	Global	2.5°x2.5°, T62 Gaussian	Daily, Monthly	1948-present	17 pressure levels, 28 spectral
NCEP/DOE Reanalysis II	Global	2.5°x2.5°	4X Daily, Daily, Monthly	1979-Dec 2012	17 Pressure levels
NOAA Extended Reconstructed SST V4	Global	1.0°x1.0°	Monthly	1854-present	None
NOAA Global Surface Temperature (NOAAGlobalTemp)	Global	5.0°x5.0°	Daily	1880-present	None
NOAA Optimum Interpolation (OI) SST V2	Global	1.0°x1.0°	Monthly,Weekly	1981-present	None
North American Regional Reanalysis (NARR)	Northern Hemisphere	32km grids	8X Daily, Daily, Monthly	1979-Dec 2012	28 Pressure
NOAA-CIRES 20th Century Reanalysis (V2)	Global	2.5°x2.5°	4X Daily	1871-2012	24 pressure levels
NOAA-CIRES 20th Century Reanalysis (V2c)	Global	2.5°x2.5°	4X Daily	1851-2014	24 pressure levels
NOAA-CIRES-DOE 20th Century Reanalysis V3	Global	1.0°x1.0°	8X Daily	1836-2015	24 pressure levels
U. of Delaware Precipitation and Air Temperature	Global Land	0.5°x0.5°	Monthly	1900-2014	None
CPC Global Temperature	Global	0.5°x0.5°	Daily	1979-present	None