U.S. Department of Commerce | National Oceanic & Atmospheric Administration | NOAA Research NOAA Earth System Research Laboratory Physical Sciences Division NCEP North American Regional Reanalysis: NARR Data set identifier: NCEP North American Regional Reanalysis (NARR) See the PSD NARR webpage for more information on PSD's involvement in the NARR project. One-Line Description: * Very High Resolution Reanalysis of the North American region including assimilated precipitation. Spatial coverage: The native model grid is converted to a Northern Lambert Conformal Conic grid which is what we archive. Corners of this grid are 12.2N;133.5W, 54.5N; 152.9W, 57.3N; 49.4W ,14.3N;65.1W (essentially, North America). The grid resolution is 349x277 which is approximately 0.3 degrees (32km) resolution at the lowest latitude. A page describing the coverage along with information on reading the projection is available. Temporal coverage: Jan 1, 1979 to Dec 31, 2009 with output every 3 hours (0z,3z...), as well as daily and monthly means for the period 1979-2009. Levels: 29 pressure levels (hPa): 1000, 975, 950, 925, 900, 875, 850, 825, 800, 775, 750, 725, 700, 650, 600, 550, 500, 450, 400, 350, 300, 275, 250, 225, 200, 175, 150, 125, 100. * soil variables: 0 , 10 , 40 , 100, (800) cm * monolevel Single level including surface and near surface, top of atmosphere and cloud heights, and entire atmosphere. Update Schedule: We plan on making all the data from 1979-2006 for our variable subset available for 8-times daily data, daily and monthly means. Source: Dataset was originally produced at NOAA's National Center for Atmospheric Prediction (NCEP) and is available in it's original grib format through NOAA NCDC's access page. It is also available in the same format from NCAR. Caveats: Useful information can be found at NCEP's NARR FAQ page and from Albany's Department of Atmospheric Science NARR Usage Notes. Usage Restrictions: * None Detailed Description: * The NARR project is an extension of the NCEP Global Reanalysis which is run over the North American Region. The NARR model uses the very high resolution NCEP Eta Model (32km/45 layer) together with the Regional Data Assimilation System (RDAS) which, significantly, assimilates precipitation along with other variables. The improvements in the model/assimilation have resulted in a dataset with substantial improvements in the accuracy of temperature, winds and precipitation compared to the NCEP-DOE Global Reanalysis 2. We currently have output from Jun 2006 which includes 8 times daily data at 29 levels and most of the variables. For a complete list of model output variables, see NCEP's variable list. * Additional information can be found at NCEP's NARR page. Related File Naming & Structure Information: File Names: * 8-times daily and daily - File names are composed of variable abbreviations and year/month or just year: as yyyymm.nc or yyyy.nc In directory: /Datasets/NARR/ or /Datasets/NARR/Dailies * Monthly means/ltms are (variable).mon.mean.nc in /Datasets/NARR/Monthlies Dataset Format and Size: * All data are stored in PSD standard NetCDF files and are (packed). * The data are divided by variable and year and month into separate files * There are 2100 files currently * Size of file is about 1.4G per variable per year/month for 8xdaily data * Size of file is about 68M per variable per /month for monthly data * Current total of 29.4 Tbytes for 8xDaily. * 8x daily data are available from ftp.cdc.noaa.gov in /Datasets/NARR/. * The 8x data files are quite large, so you may only be able to download them if you have a fast network connection. Missing Data: * Missing data is flagged with a value of 32767s. Citation: * Please note: If you acquire NCEP Reanalysis data products from PSD, we ask that you acknowledge us in your use of the data. This may be done by including text such as NCEP Reanalysis data provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their Web site at http://www.cdc.noaa.gov/ in any documents or publications using these data. We would also appreciate receiving a copy of the relevant publications. This will help PSD to justify keeping the NCEP Reanalysis data set freely available online in the future. Thank you! * NORTH AMERICAN REGIONAL REANALYSIS: A long-term, consistent, high-resolution climate dataset for the North American domain, as a major improvement upon the earlier global reanalysis datasets in both resolution and accuracy, Fedor Mesinger et. al, submitted to BAMS 2004. References: * NORTH AMERICAN REGIONAL REANALYSIS: A long-term, consistent, high-resolution climate dataset for the North American domain, as a major improvement upon the earlier global reanalysis datasets in both resolution and accuracy, Fedor Mesinger et. al, submitted to BAMS 2004. _________________________________________________________________ The NCEP NARR descriptions here will be subdivided into separate sections: Pressure level, Monolevel (surface and others) and Subsurface * Pressure * Monolevel * Subsurface _________________________________________________________________ Pressure Level Data Archive parameters: File names are composed of variable abbreviations and year/month: (variable).(year)(mm).nc Note: These variables are instantaneous values at the reference time. Variable units Abbreviation Statistic Plot/Subset Data Download sample netCDF File Geopotential Height m hgt hgt.197901.nc Zonal Wind m/s uwnd uwnd.197901.nc Meridional Wind m/s vwnd vwnd.197901.nc Omega Pa/s omega omega.197901.nc Air Temperature K air air.197901.nc Specific Humidity kg/kg shum shum.197901.nc Turbulent Kinetic Energy J/kg tke tke.197901.nc Detailed description: The NARR project is an extension of the NCEP Global Reanalysis which is run over the North American Region. The NARR model uses the very high resolution NCEP Eta Model (32km/45 layer) together with the Regional Data Assimilation System (RDAS) which, significantly, assimilates precipitation along with other variables. The improvements in the model/assimilation have resulted in a dataset with substantial improvements in the accuracy of temperature, winds and precipitation compared to the NCEP-DOE Global Reanalysis 2. The model currently has output from Jan 1, 1979-Dec 31 2004 which includes 8 times daily data at 29 levels. Currently, CDC makes available the pressure level data only (Jan 1979-Dec 2004) though we plan to later make available most of the surface and upper atmospheric variables for the complete time period. For a complete list of model output variables, see NCEP's variable list. Additional information can be found at NCEP's NARR page. Please note: If you acquire NCEP Reanalysis data products from CDC, we ask that you acknowledge us in your use of the data. This may be done by including text such as NCEP Reanalysis data provided by the NOAA-CIRES Climate Diagnostics Center, Boulder, Colorado, USA, from their Web site at http://www.cdc.noaa.gov/ in any documents or publications using these data. We would also appreciate receiving a copy of the relevant publications. This will help CDC to justify keeping the NCEP Reanalysis data set freely available online in the future. Thank you! Data set format and size: * All data are stored in netCDF files * The data are divided by variable and year and month into separate files * There are 2100 files currently * Size of file is about 1.4G per variable per year/month for 8xdaily data * Current total of 29.4 Tbytes for 8xDaily. Availability and usage restrictions: * By anonymous FTP: + 8x daily data are available from ftp.cdc.noaa.gov in /Datasets/NARR/. + The 8x data files are quite large, so you may only be able to download them if you have a fast network connection. * No usage restrictions. _________________________________________________________________ Other General Information References: * Please use this reference if you use the dataset.: NORTH AMERICAN REGIONAL REANALYSIS: A long-term, consistent, high-resolution climate dataset for the North American domain, as a major improvement upon the earlier global reanalysis datasets in both resolution and accuracy, Fedor Mesinger et. al, submitted to BAMS 2004.. Contact: * Physical Sciences Division: Data Management NOAA/ESRL/PSD 325 Broadway Boulder, CO 80305-3328 esrl.psd.data@noaa.gov U.S. Department of Commerce | National Oceanic and Atmospheric Administration Earth System Research Laboratory | Physical Sciences Division Current page: http://www.cdc.noaa.gov/cdc/data.narr.html Contact the Webmaster (webmaster.psd@noaa.gov)