Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the secondary forcing data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format is WMO GRIB-1. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. NLDAS-2 is providing a second forcing file, "File B", in which the surface temperature, humidity, and wind fields are represented not at 2-meters and 10-meters above the height of the NLDAS terrain, but rather at the same height above the NLDAS terrain as the height above the NARR terrain of the lowest prognostic level of the NARR assimilation system (namely, the same height above the model terrain as the lowest prognostic level of the mesoscale Eta model, which is the assimilating model in NARR). The surface downward surface radiation field in "File B" is taken directly from NARR, without any bias correction. The precipitation and convective precipitation fields in "File B" are also taken directly from NARR, and are used to calculate the convective fraction provided in "File A". The aerodynamic conductance is "File B" is also taken from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs /gribtab_NLDAS_FORB_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
The reprocessed OMI/Aura Level-2 cloud data product OMCLDO2 is now available from the NASA GoddardEarth Sciences Data and Information Services Center (GES DISC) for the public access.It is the second release of Version 003 and was reprocessed late 2011. (The shortname for this Level-2 OMI cloud product is OMCLDO2) OMI provides two cloud products based on two different algorithms, the Rotational Raman Scattering method and O2-O2 absorption method using the DOAS technique. This level-2 global cloud product at the pixel resolution (13x24 km2 at nadir) is based on the spectral fitting of O2-O2 absorption band at 477 nm using DOAS technique. This product contains cloud pressure, cloud fraction, slant column O2-O2; O3, Ring coefficients, uncertainties in derived parameters, terrain and geolocation information, solar and satellite viewing angles, and quality flags. The shortname for this Level-2 OMI cloud product is OMCLDO2 and the lead scientist for this product is Dr. Pepijn Veefkind. OMCLDO2 product files are stored in Hierarchical Data Format (HDF-EOS5). Each file contains data from the day lit portion of an orbit (~53 minutes) and is roughly 15.096 MB in size. There are approx 14 orbits per day thus the total data volume is approximately 200 GB/day. A Readme document containing brief algorithm description and known data quality related issues and file spec are provided by the OMCLDO2 Algorithm lead (see http://disc.sci.gsfc.nasa.gov/Aura/secondary/documentation/OMI_DUG.pdf ).
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the secondary forcing data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format is WMO GRIB-1. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. NLDAS-2 is providing a second forcing file, "File B", in which the surface temperature, humidity, and wind fields are represented not at 2-meters and 10-meters above the height of the NLDAS terrain, but rather at the same height above the NLDAS terrain as the height above the NARR terrain of the lowest prognostic level of the NARR assimilation system (namely, the same height above the model terrain as the lowest prognostic level of the mesoscale Eta model, which is the assimilating model in NARR). The surface downward surface radiation field in "File B" is taken directly from NARR, without any bias correction. The precipitation and convective precipitation fields in "File B" are also taken directly from NARR, and are used to calculate the convective fraction provided in "File A". The aerodynamic conductance is "File B" is also taken from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs /gribtab_NLDAS_FORB_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly climatology data of the secondary forcing data for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing. The temporal resolution is monthly, ranging from January to December. The NLDAS-2 monthly climatology data are the monthly data averaged over the thirty years (1980 - 2009) of the NLDAS-2 monthly data. The file format is WMO GRIB-1. Brief description about the NLDAS-2 hourly and monthly primary forcing data can be found from the GCMD DIFs for GES_DISC_NLDAS_FORB0125_H_V002 and GES_DISC_NLDAS_FORB0125_M_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORB0125_H_V002 and http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORB0125_M_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The NLDAS-2 monthly climatology land surface forcing fields are grouped into two GRIB files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORB_monthly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
The collection-3 Chlorine Dioxide Product OMOCLO from the Aura-OMI, is now available (http://disc.gsfc.nasa.gov/Aura/OMI/omoclo_v003.shtml) from the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) for the public access. (The shortname for this Level-2 OMI total column OClO product is OMOCLO) The algorithm leads for this product are the US OMI scientists Dr. Kelly Chance (kchance@cfa.harvard.edu) and Dr. Thomas Kurosu (tkurosu@cfa.harvard.edu) from the Harvard-Smithsonian Center, Cambridge, MA. The OMOCLO product contains slant column OClO, standard erros (rms and sigma), quality flags, geolocation and other ancillary information. OMOCLO files are stored in EOS Hierarchical Data Format (HDF-EOS5). Each file contains data from the day lit portion of an orbit (~53 minutes). There are approximately 14 orbits per day. The maximum file size for the OMOCLO data product is about 20 Mbytes. A short OMOCLO Readme Document that includes brief algorithm description and documents that provides known data quality related issues are available from the Harvard-Smithsonian Center site: http://www.cfa.harvard.edu/~tkurosu/SatelliteInstruments/OMI/PGEReleases/
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the secondary forcing data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format is WMO GRIB-1. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. NLDAS-2 is providing a second forcing file, "File B", in which the surface temperature, humidity, and wind fields are represented not at 2-meters and 10-meters above the height of the NLDAS terrain, but rather at the same height above the NLDAS terrain as the height above the NARR terrain of the lowest prognostic level of the NARR assimilation system (namely, the same height above the model terrain as the lowest prognostic level of the mesoscale Eta model, which is the assimilating model in NARR). The surface downward surface radiation field in "File B" is taken directly from NARR, without any bias correction. The precipitation and convective precipitation fields in "File B" are also taken directly from NARR, and are used to calculate the convective fraction provided in "File A". The aerodynamic conductance is "File B" is also taken from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs /gribtab_NLDAS_FORB_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
The collection-3 Chlorine Dioxide Product OMOCLO from the Aura-OMI, is now available (http://disc.gsfc.nasa.gov/Aura/OMI/omoclo_v003.shtml) from the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) for the public access. (The shortname for this Level-2 OMI total column OClO product is OMOCLO) The algorithm leads for this product are the US OMI scientists Dr. Kelly Chance (kchance@cfa.harvard.edu) and Dr. Thomas Kurosu (tkurosu@cfa.harvard.edu) from the Harvard-Smithsonian Center, Cambridge, MA. The OMOCLO product contains slant column OClO, standard erros (rms and sigma), quality flags, geolocation and other ancillary information. OMOCLO files are stored in EOS Hierarchical Data Format (HDF-EOS5). Each file contains data from the day lit portion of an orbit (~53 minutes). There are approximately 14 orbits per day. The maximum file size for the OMOCLO data product is about 20 Mbytes. A short OMOCLO Readme Document that includes brief algorithm description and documents that provides known data quality related issues are available from the Harvard-Smithsonian Center site: http://www.cfa.harvard.edu/~tkurosu/SatelliteInstruments/OMI/PGEReleases/
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly secondary forcing data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is monthly. The file format is WMO GRIB-1. The NLDAS-2 monthly secondary forcing data were generated from the NLDAS-2 hourly secondary forcing data, as monthly accumulation for precipitation and convective precipitation and monthly average for other variables. Monthly period of each month is from 00Z at start of the month to 23:59Z at end of the month. The one exception to this is the first month (Jan. 1979) that starts from 00Z 02 Jan 1979, except for the monthly accumulated precipitation and convective precipitation that both start from 12Z 01 Jan 1979. Brief description about the NLDAS-2 hourly secondary forcing data can be found from the GCMD DIF for GES_DISC_NLDAS_FORB0125_H_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORB0125_H_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The NLDAS-2 monthly land surface forcing fields are grouped into two GRIB files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORB_monthly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly primary forcing data "File A" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is monthly. The file format is WMO GRIB-1. The NLDAS-2 monthly primary forcing data were generated from the NLDAS-2 hourly primary forcing data, as monthly accumulation for total precipitation, convective precipitation, and potential evaporation, and monthly average for other variables. The convective precipitation monthly total is the hourly convective fraction multiplied by the hourly precipitation (both from the NLDAS-2 "File A" files), and then summed over all hours of the month. Monthly period of each month is from 00Z at start of the month to 23:59Z at end of the month. The one exception to this is the first month (Jan. 1979) that starts from 00Z 02 Jan 1979, except for the monthly accumulated precipitation and convective precipitation that both start from 12Z 01 Jan 1979. Brief description about the NLDAS-2 hourly primary forcing data can be found from the GCMD DIF for GES_DISC_NLDAS_FORA0125_H_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_H_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The monthly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_monthly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the secondary forcing data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format is WMO GRIB-1. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. NLDAS-2 is providing a second forcing file, "File B", in which the surface temperature, humidity, and wind fields are represented not at 2-meters and 10-meters above the height of the NLDAS terrain, but rather at the same height above the NLDAS terrain as the height above the NARR terrain of the lowest prognostic level of the NARR assimilation system (namely, the same height above the model terrain as the lowest prognostic level of the mesoscale Eta model, which is the assimilating model in NARR). The surface downward surface radiation field in "File B" is taken directly from NARR, without any bias correction. The precipitation and convective precipitation fields in "File B" are also taken directly from NARR, and are used to calculate the convective fraction provided in "File A". The aerodynamic conductance is "File B" is also taken from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs /gribtab_NLDAS_FORB_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly secondary forcing data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is monthly. The file format is WMO GRIB-1. The NLDAS-2 monthly secondary forcing data were generated from the NLDAS-2 hourly secondary forcing data, as monthly accumulation for precipitation and convective precipitation and monthly average for other variables. Monthly period of each month is from 00Z at start of the month to 23:59Z at end of the month. The one exception to this is the first month (Jan. 1979) that starts from 00Z 02 Jan 1979, except for the monthly accumulated precipitation and convective precipitation that both start from 12Z 01 Jan 1979. Brief description about the NLDAS-2 hourly secondary forcing data can be found from the GCMD DIF for GES_DISC_NLDAS_FORB0125_H_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORB0125_H_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The NLDAS-2 monthly land surface forcing fields are grouped into two GRIB files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORB_monthly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the primary forcing data "File A" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format is WMO GRIB-1. Details about the generation of the NLDAS-2 forcing data sets can be found in Xia et al. (2012). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. Additionally, the fields of surface pressure, surface downward longwave radiation, near-surface air temperature, and near-surface specific humidity are adjusted vertically to account for the vertical difference between the NARR and NLDAS fields of terrain height. This vertical adjustment applies the traditional vertical lapse rate of 6.5 K/km for air temperature. The details of the spatial interpolation, temporal disaggregation, and vertical adjustment are those employed in NLDAS-1, as presented by Cosgrove et al. (2003). The surface downward shortwave radiation field in "File A" is a bias-corrected field wherein a bias-correction algorithm was applied to the NARR surface downward shortwave radiation. This bias correction utilizes five years (1996-2000) of the hourly 1/8th-degree GOES-based surface downward shortwave radiation fields derived by Pinker et al. (2003). The potential evaporation field in "File A" is that computed in NARR using the modified Penman scheme of Mahrt and Ek (1984). The precipitation field in "File A" is not the NARR precipitation forcing, but is rather a product of a temporal disaggregation of a gauge-only CPC analysis of daily precipitation, performed directly on the NLDAS grid and including an orographic adjustment based on the widely-applied PRISM climatology. The precipitation is temporally disaggregated into hourly fields by deriving hourly disaggregation weights from either WSR-88D Doppler radar-based precipitation estimates, 8-km CMORPH hourly precipitation analyses, or NARR-simulated precipitation (based on availability, in order). The latter fields from radar, CMORPH, and NARR are used only to derive disaggregation weights and do not change the daily total precipitation. The field in "File A" that gives the fraction of total precipitation that is convective is an estimate derived from the following two NARR precipitation fields (which are provided in "File B"): NARR total precipitation and NARR convective precipitation (the latter is less than or equal to the NARR total precipitation and can be zero). The Convective Available Potential Energy (CAPE) is the final variable in the forcing data set, also interpolated from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the secondary forcing data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format is WMO GRIB-1. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. NLDAS-2 is providing a second forcing file, "File B", in which the surface temperature, humidity, and wind fields are represented not at 2-meters and 10-meters above the height of the NLDAS terrain, but rather at the same height above the NLDAS terrain as the height above the NARR terrain of the lowest prognostic level of the NARR assimilation system (namely, the same height above the model terrain as the lowest prognostic level of the mesoscale Eta model, which is the assimilating model in NARR). The surface downward surface radiation field in "File B" is taken directly from NARR, without any bias correction. The precipitation and convective precipitation fields in "File B" are also taken directly from NARR, and are used to calculate the convective fraction provided in "File A". The aerodynamic conductance is "File B" is also taken from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs /gribtab_NLDAS_FORB_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly climatology data of the primary forcing data for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing. The temporal resolution is monthly, ranging from January to December. The NLDAS-2 monthly climatology data are the monthly data averaged over the thirty years (1980 - 2009) of the NLDAS-2 monthly data. The file format is WMO GRIB-1. Brief description about the NLDAS-2 hourly and monthly primary forcing data can be found from the GCMD DIFs for GES_DISC_NLDAS_FORA0125_H_V002 and GES_DISC_NLDAS_FORA0125_M_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_H_V002 and http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_M_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The monthly climatology land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the secondary forcing data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format is WMO GRIB-1. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. NLDAS-2 is providing a second forcing file, "File B", in which the surface temperature, humidity, and wind fields are represented not at 2-meters and 10-meters above the height of the NLDAS terrain, but rather at the same height above the NLDAS terrain as the height above the NARR terrain of the lowest prognostic level of the NARR assimilation system (namely, the same height above the model terrain as the lowest prognostic level of the mesoscale Eta model, which is the assimilating model in NARR). The surface downward surface radiation field in "File B" is taken directly from NARR, without any bias correction. The precipitation and convective precipitation fields in "File B" are also taken directly from NARR, and are used to calculate the convective fraction provided in "File A". The aerodynamic conductance is "File B" is also taken from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs /gribtab_NLDAS_FORB_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the primary forcing data "File A" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format is WMO GRIB-1. Details about the generation of the NLDAS-2 forcing data sets can be found in Xia et al. (2012). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. Additionally, the fields of surface pressure, surface downward longwave radiation, near-surface air temperature, and near-surface specific humidity are adjusted vertically to account for the vertical difference between the NARR and NLDAS fields of terrain height. This vertical adjustment applies the traditional vertical lapse rate of 6.5 K/km for air temperature. The details of the spatial interpolation, temporal disaggregation, and vertical adjustment are those employed in NLDAS-1, as presented by Cosgrove et al. (2003). The surface downward shortwave radiation field in "File A" is a bias-corrected field wherein a bias-correction algorithm was applied to the NARR surface downward shortwave radiation. This bias correction utilizes five years (1996-2000) of the hourly 1/8th-degree GOES-based surface downward shortwave radiation fields derived by Pinker et al. (2003). The potential evaporation field in "File A" is that computed in NARR using the modified Penman scheme of Mahrt and Ek (1984). The precipitation field in "File A" is not the NARR precipitation forcing, but is rather a product of a temporal disaggregation of a gauge-only CPC analysis of daily precipitation, performed directly on the NLDAS grid and including an orographic adjustment based on the widely-applied PRISM climatology. The precipitation is temporally disaggregated into hourly fields by deriving hourly disaggregation weights from either WSR-88D Doppler radar-based precipitation estimates, 8-km CMORPH hourly precipitation analyses, or NARR-simulated precipitation (based on availability, in order). The latter fields from radar, CMORPH, and NARR are used only to derive disaggregation weights and do not change the daily total precipitation. The field in "File A" that gives the fraction of total precipitation that is convective is an estimate derived from the following two NARR precipitation fields (which are provided in "File B"): NARR total precipitation and NARR convective precipitation (the latter is less than or equal to the NARR total precipitation and can be zero). The Convective Available Potential Energy (CAPE) is the final variable in the forcing data set, also interpolated from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This monthly climatology data set contains a series of land surface parameters simulated from the Noah land-surface model (LSM) for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing. The temporal resolution is monthly, ranging from January to December. The NLDAS-2 monthly climatology data are the monthly data averaged over the thirty years (1980 - 2009) of the NLDAS-2 monthly data. The file format is WMO GRIB-1. Brief description about the NLDAS-2 hourly and monthly Noah LSM data can be found from the GCMD DIFs for GES_DISC_NLDAS_NOAH0125_H_V002 and GES_DISC_NLDAS_NOAH0125_M_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_NOAH0125_H_V002 and http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_NOAH0125_M_V002. Details about the NLDAS-2 configuration of the Noah LSM can be found in Xia et al. (2012). The NLDAS-2 Noah monthly climatology data contain fifty-two fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_NOAH.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. There are four vertical levels for the Soil Moisture Content (PDS 086) and Soil Temperature (PDS 085) in the Noah GRIB files. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf or the GrADS ctl file at ftp://hydro1.sci.gsfc.nasa.gov/data/gds/NLDAS/NLDAS_NOAH0125_MC.002.ctl.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly climatology data of the primary forcing data for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing. The temporal resolution is monthly, ranging from January to December. The NLDAS-2 monthly climatology data are the monthly data averaged over the thirty years (1980 - 2009) of the NLDAS-2 monthly data. The file format is WMO GRIB-1. Brief description about the NLDAS-2 hourly and monthly primary forcing data can be found from the GCMD DIFs for GES_DISC_NLDAS_FORA0125_H_V002 and GES_DISC_NLDAS_FORA0125_M_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_H_V002 and http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_M_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The monthly climatology land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly climatology data of the primary forcing data for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing. The temporal resolution is monthly, ranging from January to December. The NLDAS-2 monthly climatology data are the monthly data averaged over the thirty years (1980 - 2009) of the NLDAS-2 monthly data. The file format is WMO GRIB-1. Brief description about the NLDAS-2 hourly and monthly primary forcing data can be found from the GCMD DIFs for GES_DISC_NLDAS_FORA0125_H_V002 and GES_DISC_NLDAS_FORA0125_M_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_H_V002 and http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_M_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The monthly climatology land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly primary forcing data "File A" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is monthly. The file format is WMO GRIB-1. The NLDAS-2 monthly primary forcing data were generated from the NLDAS-2 hourly primary forcing data, as monthly accumulation for total precipitation, convective precipitation, and potential evaporation, and monthly average for other variables. The convective precipitation monthly total is the hourly convective fraction multiplied by the hourly precipitation (both from the NLDAS-2 "File A" files), and then summed over all hours of the month. Monthly period of each month is from 00Z at start of the month to 23:59Z at end of the month. The one exception to this is the first month (Jan. 1979) that starts from 00Z 02 Jan 1979, except for the monthly accumulated precipitation and convective precipitation that both start from 12Z 01 Jan 1979. Brief description about the NLDAS-2 hourly primary forcing data can be found from the GCMD DIF for GES_DISC_NLDAS_FORA0125_H_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_H_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The monthly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_monthly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly primary forcing data "File A" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is monthly. The file format is WMO GRIB-1. The NLDAS-2 monthly primary forcing data were generated from the NLDAS-2 hourly primary forcing data, as monthly accumulation for total precipitation, convective precipitation, and potential evaporation, and monthly average for other variables. The convective precipitation monthly total is the hourly convective fraction multiplied by the hourly precipitation (both from the NLDAS-2 "File A" files), and then summed over all hours of the month. Monthly period of each month is from 00Z at start of the month to 23:59Z at end of the month. The one exception to this is the first month (Jan. 1979) that starts from 00Z 02 Jan 1979, except for the monthly accumulated precipitation and convective precipitation that both start from 12Z 01 Jan 1979. Brief description about the NLDAS-2 hourly primary forcing data can be found from the GCMD DIF for GES_DISC_NLDAS_FORA0125_H_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_H_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The monthly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_monthly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the monthly climatology data of the primary forcing data for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing. The temporal resolution is monthly, ranging from January to December. The NLDAS-2 monthly climatology data are the monthly data averaged over the thirty years (1980 - 2009) of the NLDAS-2 monthly data. The file format is WMO GRIB-1. Brief description about the NLDAS-2 hourly and monthly primary forcing data can be found from the GCMD DIFs for GES_DISC_NLDAS_FORA0125_H_V002 and GES_DISC_NLDAS_FORA0125_M_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_H_V002 and http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_FORA0125_M_V002. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012). The monthly climatology land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains a series of land surface parameters simulated from the Noah land-surface model (LSM) for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is monthly. The file format is WMO GRIB-1. The NLDAS-2 monthly Noah model data were generated from the NLDAS-2 hourly Noah model data, as monthly accumulation for rainfall, snowfall, subsurface runoff, surface runoff, total evapotranspiration, and snow melt, and monthly average for other variables. Monthly period of each month is from 00Z at start of the month to 23:59Z at end of the month, except the first month (Jan 1979) that starts from 00Z 02 Jan 1979. Also for the first month (Jan 1979), because the variables listed as instantaneous in the README file (http://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf) do not have valid data exactly on 00Z 02 Jan 1979, and this one hour is not included in the average for this month only. Brief description about the NLDAS-2 monthly Noah model can be found from the GCMD DIF for GES_DISC_NLDAS_NOAH0125_H_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_NOAH0125_H_V002. Details about the NLDAS-2 configuration of the Noah LSM can be found in Xia et al. (2012). The NLDAS-2 Noah monthly data contain fifty-two fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_NOAH.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For information about the vertical layers of the Soil Moisture Content (PDS 086), Soil Temperature (PDS 085), and Liquid Soil Moisture Content (PDS 151) please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf or the GrADS ctl file at ftp://hydro1.sci.gsfc.nasa.gov/data/gds/NLDAS/NLDAS_NOAH0125_M.002.ctl.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains a series of land surface parameters simulated from the Noah land-surface model (LSM) for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is monthly. The file format is WMO GRIB-1. The NLDAS-2 monthly Noah model data were generated from the NLDAS-2 hourly Noah model data, as monthly accumulation for rainfall, snowfall, subsurface runoff, surface runoff, total evapotranspiration, and snow melt, and monthly average for other variables. Monthly period of each month is from 00Z at start of the month to 23:59Z at end of the month, except the first month (Jan 1979) that starts from 00Z 02 Jan 1979. Also for the first month (Jan 1979), because the variables listed as instantaneous in the README file (http://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf) do not have valid data exactly on 00Z 02 Jan 1979, and this one hour is not included in the average for this month only. Brief description about the NLDAS-2 monthly Noah model can be found from the GCMD DIF for GES_DISC_NLDAS_NOAH0125_H_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_NOAH0125_H_V002. Details about the NLDAS-2 configuration of the Noah LSM can be found in Xia et al. (2012). The NLDAS-2 Noah monthly data contain fifty-two fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_NOAH.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For information about the vertical layers of the Soil Moisture Content (PDS 086), Soil Temperature (PDS 085), and Liquid Soil Moisture Content (PDS 151) please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf or the GrADS ctl file at ftp://hydro1.sci.gsfc.nasa.gov/data/gds/NLDAS/NLDAS_NOAH0125_M.002.ctl.
Published By National Aeronautics and Space Administration
Issued over 9 years ago
Summary
Description
This data set contains the primary forcing data "File A" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format is WMO GRIB-1. Details about the generation of the NLDAS-2 forcing data sets can be found in Xia et al. (2012). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. Additionally, the fields of surface pressure, surface downward longwave radiation, near-surface air temperature, and near-surface specific humidity are adjusted vertically to account for the vertical difference between the NARR and NLDAS fields of terrain height. This vertical adjustment applies the traditional vertical lapse rate of 6.5 K/km for air temperature. The details of the spatial interpolation, temporal disaggregation, and vertical adjustment are those employed in NLDAS-1, as presented by Cosgrove et al. (2003). The surface downward shortwave radiation field in "File A" is a bias-corrected field wherein a bias-correction algorithm was applied to the NARR surface downward shortwave radiation. This bias correction utilizes five years (1996-2000) of the hourly 1/8th-degree GOES-based surface downward shortwave radiation fields derived by Pinker et al. (2003). The potential evaporation field in "File A" is that computed in NARR using the modified Penman scheme of Mahrt and Ek (1984). The precipitation field in "File A" is not the NARR precipitation forcing, but is rather a product of a temporal disaggregation of a gauge-only CPC analysis of daily precipitation, performed directly on the NLDAS grid and including an orographic adjustment based on the widely-applied PRISM climatology. The precipitation is temporally disaggregated into hourly fields by deriving hourly disaggregation weights from either WSR-88D Doppler radar-based precipitation estimates, 8-km CMORPH hourly precipitation analyses, or NARR-simulated precipitation (based on availability, in order). The latter fields from radar, CMORPH, and NARR are used only to derive disaggregation weights and do not change the daily total precipitation. The field in "File A" that gives the fraction of total precipitation that is convective is an estimate derived from the following two NARR precipitation fields (which are provided in "File B"): NARR total precipitation and NARR convective precipitation (the latter is less than or equal to the NARR total precipitation and can be zero). The Convective Available Potential Energy (CAPE) is the final variable in the forcing data set, also interpolated from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two GRIB files, "File A" and "File B". "File A" is the primary (default) forcing file and contains eleven fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_FORA_hourly.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For more information, please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf.