Reanalysis a systematic approach to produce data sets for climate monitoring and research. Reanalyses are created via an unchanging ("frozen") data assimilation scheme and model(s) which ingest all available observations every 6-12 hours over the period being analyzed. This unchanging framework...
Main variables and Earth System components:
See Expert Guidance by Dee, Dick | See Expert Guidance by Fasullo, John | See Expert Guidance by Shea, Dennis | See Expert Guidance by Walsh, John
Years of Record: 2000/02 to 2017/01
The CERES-EBAF product provides 1-degree regional, zonal and global monthly mean Top-of-Atmosphere (TOA) and surface (SFC) longwave (LW), shortwave (SW), and net (NET) fluxes under clear and all-sky conditions. EBAF is used for climate model evaluation, estimating the Earth's global mean...
Main variables and Earth System components:
Formats: netCDF
Timestep: Monthly
Domain: Global
See Expert Guidance by Loeb, Norman
Years of Record: 2000/02 to 2018/04
The Moderate Resolution Imaging Spectroradiometer (MODIS) is scanning instrument that makes measurements in 36 spectral bands from the visible to the thermal infrared at spatial resolutions from 250 m to 1 km. There are MODIS instruments aboard two sun-synchronous polar-orbiting NASA satellites:...
Main variables and Earth System components:
Formats: netCDF | HDF-EOS
Timestep: Daily,Monthly,Weekly
Domain: Global
See Expert Guidance by Pincus, Robert
Years of Record: 1978/12 to 2020/02
CMAP refers to a collection of precipitation data sets, though the 2.5°x2.5° global monthly version is probably the most widely used. This data set is constructed from an analysis of gauge data and satellite-derived precipitation estimates. An "enhanced" version (CMAP/A) is also available, which...
Main variables and Earth System components:
Formats: netCDF | ascii
Timestep: Monthly,Pentad
Domain: Global
See Expert Guidance by Arkin, Phil | See Expert Guidance by Xie, PIngping
Years of Record: 2006/06 to 2011/01
A global (82S-82N) cloud fraction data set, providing a unique view of cloud vertical structure, has been developed based on the complimentary spaceborne remote sensing capabilities of the CloudSat radar and the CALISPSO lidar. The data set provides monthly mean cloud fraction over several vertical...
Main variables and Earth System components:
Formats: netCDF
Timestep: Monthly,Seasonal,Annual
Domain: Global
See Expert Guidance by Kay, Jennifer
Years of Record: 1948/12 to 2006/11
The Coordinated Ocean Research Experiments version 2 (COREv2) data set consists of a globally complete set of air-sea fluxes of momentum, heat and freshwater for 1948-2009 at monthly resolution. This data set serves as a set of common atmospheric boundary conditions that has been used...
Main variables and Earth System components:
Formats: netCDF
Timestep: Monthly
Domain: Global
Atmosphere | Evaporation | Precipitation | Radiation | Wind Stress | Land | Runoff and Streamflow | Ocean | Surface Flux
See Expert Guidance by Yeager, Stephen
Cloud processes and feedbacks are recognized as the largest uncertainty in climate model projections of climate change. Progress in understanding the roles of clouds in climate change has in part been hampered by the lack of a consistent definition of clouds and cloud types in models and...
Main variables and Earth System components:
Domain: Global
See Expert Guidance by Kay, Jennifer
Years of Record: 1984/12 to 1989/11
The Goddard Space Flight Center built the Earth Radiation Budget Satellite (ERBS) on which the first ERBE instruments were launched by the Space Shuttle Challenger in 1984. ERBE instruments were also launched on two National Oceanic and Atmospheric Administration weather monitoring satellites, NOAA...
Main variables and Earth System components:
Formats: netCDF
Timestep: Monthly
Domain: Global Years of Record: 1978/12 to 1993/11
The ERA-15 production system generated re-analyses for 15 years (1979-1993) using a special version of their 1995 operational data assimilation system and model. The resulting analyses include full model resolution analyses or reduced resolution analyses and climate and statistics data...
Main variables and Earth System components:
Formats: GRIB
Timestep: Sub-daily,Monthly
Domain: Global
See Expert Guidance by Shea, Dennis
Years of Record: 1978/12 to 2019/08
Using a much improved atmospheric model and assimilation system from those used in ERA-40, ERA-Interim represents a third generation reanalysis. Several of the inaccuracies exhibited by ERA-40 such as too-strong precipitation over oceans from the early 1990's onwards and a too-strong Brewer-Dobson...
Main variables and Earth System components:
Formats: netCDF | GRIB
Timestep: Sub-daily,Daily,Monthly
Domain: Global
See Expert Guidance by Dee, Dick
Years of Record: 1957/08 to 2002/07
ERA 40 is a second generation reanalysis. It is the first reanalysis to directly assimilate satellite radiance data (TOVS, SSM/I, ERS and ATOVS). Cloud Motion Winds are also used. The result is better circulation over the tropics and southern hemisphere. However, unless comparing to previous...
Main variables and Earth System components:
Formats: netCDF | GRIB
Timestep: Sub-daily,Monthly
Domain: Global 
Years of Record: 1899/12 to 2014/11
A series of gridded temperature and precipitation data sets. Station records that served as bases for the Terrestrial Air Temperature: 1900-2014 Gridded Monthly Time Series (Version 4.01) and Terrestrial Precipitation: 1900-2014 Gridded Monthly Time Series (Version 4.01) archives are used here to...
Main variables and Earth System components:
Formats: netCDF | ascii
Timestep: Climatology,Monthly
Domain: Global
See Expert Guidance by Matsuura, Kenji
Years of Record: 1890/12 to 2018/11
The GPCC provides gridded gauge-analysis products derived from quality controlled station data. Two products are for climate: (a) the Full Data Reanalysis Product (1901-2010) is recommended for global and regional water balance studies, calibration/validation of remote sensing based rainfall...
Main variables and Earth System components:
Formats: netCDF | ascii
Timestep: Climatology,Daily,Monthly
Domain: Global 
Years of Record: 1978/12 to 2020/06
Data from rain gauge stations, satellites, and sounding observations have been merged to estimate monthly rainfall on a 2.5-degree global grid from 1979 to the present. The careful combination of satellite-based rainfall estimates provides the most complete analysis of rainfall available to date...
Main variables and Earth System components:
Formats: netCDF | binary
Timestep: Climatology,Monthly
Domain: Global
See Expert Guidance by Pendergrass, Angeline | See Expert Guidance by Wang, Jian-Jian
Years of Record: 1953/12 to 2009/11
This digital archive provides multi-year monthly, seasonal, and annual averages in 5x5-degree grid boxes (or 10x10-degree boxes for some quantities over the ocean). Daytime and nighttime averages, as well as the diurnal average (average of day and night), are given. Nighttime averages were computed...
Main variables and Earth System components:
Formats: ascii
Timestep: Climatology,Monthly,Seasonal
Domain: Global
See Expert Guidance by Norris, Joel
Years of Record: 1983/06 to 2009/11
The International Satellite Cloud Climatology Project (ISCCP) makes use of routine observations by operational weather satellites to provide a long-term (1983-2009), gridded, global record of cloud properties. ISCCP uses observations in the visible and infrared window portions of the spectrum to...
Main variables and Earth System components:
Formats: netCDF | binary | HDF
Timestep: Climatology,Sub-daily,Monthly
Domain: Global
See Expert Guidance by Pincus, Robert
Years of Record: 1978/12 to 2004/11
JRA-25 is a second generation reanalysis product. The model and data assimilation are from the operational system in April 2004. It was the first reanalysis to assimilate wind profiles around tropical cyclones deduced from best-track data, resulting in improved tropical cyclone analysis in a global...
Main variables and Earth System components:
Formats: GRIB
Timestep: Sub-daily,Monthly
Domain: Global Years of Record: 1997/12 to 2008/11
"This work describes a new climatology of cloud liquid water path (LWP), termed the University of Wisconsin (UWisc) climatology, derived from 18 yr of satellite-based passive microwave observations over the global oceans. The climatology is based on a modern retrieval methodology applied...
Main variables and Earth System components:
Formats: netCDF
Timestep: Climatology,Monthly
Domain: Global Years of Record: 1869/12 to 2020/07
The merged Hadley-OI sea surface temperature (SST) and sea ice concentration (SIC) data sets were specifically developed as surface forcing data sets for AMIP style uncoupled simulations of the Community Atmosphere Model (CAM). The Hadley Centre's SST/SIC version 1.1 (HADISST1), which is derived...
Main variables and Earth System components:
Formats: netCDF
Timestep: Monthly
Domain: Global, Antarctic, Arctic, NH - Northern Hemisphere, SH - Southern Hemisphere Years of Record: 1978/12 to 2016/01
The Modern Era Retrospective-Analysis for Research and Applications (MERRA) was undertaken by NASA’s Global Modeling and Assimilation Office with two primary objectives: to place observations from NASA’s Earth Observing System satellites into a climate context and to improve upon the hydrologic...
Main variables and Earth System components:
Formats: netCDF | HDF
Timestep: Sub-daily,Monthly
Domain: Global Years of Record: 1947/12 to 2021/09
NCEP-NCAR (R1) is the original reanalysis effort. It uses a frozen global state-of-the-art global data assimilation system (as of 11 January 1995). The original database was enhanced (additional, quality checked datasets) by NCAR's Data Support Section. Originally planned to span 1957-96 ("40-Year...
Main variables and Earth System components:
Formats: netCDF | GRIB
Timestep: Sub-daily,Daily,Monthly
Domain: Global 
Years of Record: 1850/11 to 2014/11
The Twentieth Century Reanalysis (20CR) provides a comprehensive global atmospheric circulation data set spanning 1850-2014. Its chief motivation is to provide an observational validation data set, with quantified uncertainties, for assessing climate model simulations of the 20th century, with...
Main variables and Earth System components:
Formats: netCDF | GRIB
Timestep: Sub-daily,Daily,Monthly
Domain: Global Years of Record: 1947/12 to 2020/02
Precipitation gauge measurements over land from the GHCN-v2 (Global Historical Climatology Network version 2) are interpolated onto 3 grids: at 0.5, 1 and 2.5 degree resolutions via optimal interpolation. Note: As of May, 2011 the GHCN version 3 station data set is available.
Main variables and Earth System components:
Formats: netCDF | ascii | binary
Timestep: Monthly
Domain: Global Years of Record: 1987/12 to 2001/11
The NASA Water Vapor Project (NVAP) total column water vapor (aka, precipitable water) data sets comprise a combination of radiosonde observations, Television and Infrared Operational Satellite (TIROS) Operational Vertical Sounders (TOVS), and Special Sensor Microwave/Imager (SSM/I) data sets....
Main variables and Earth System components:
Formats: binary
Timestep: Daily,Monthly
Domain: Global 