The 5-degree latitude/longitude grids contained in this dataset make up the longest continuous set of daily gridded Northern Hemisphere sea-level pressure data in the DSS archive. These grids have been assembled by DSS from the grids of various meteorological chart digitization projects and operational analyses. Grids begin in 1899 and cover the Northern Hemisphere from 15N to the North Pole. The dataset continues to be updated regularly as new data become available.

In the earlier years, there is one grid per day, but from July 1962 on, there are two grids per day. Prior to 1946, the original grids had a 10-degree resolution and the intermediate points were interpolated and indicated as such. Also in this period, there are times when large numbers of gridpoints are missing, particularly over the Asian continent. For more information, see the documentation about original data points.

This dataset contains the longest continuous time series of monthly gridded Northern Hemisphere sea-level pressure data in the DSS archive. The 5-degree latitude/longitude grids, computed from the daily grids in ds010.0, begin in 1899 and cover the Northern Hemisphere from 15N to the North Pole. The dataset continues to be updated regularly as new data become available.

Each monthly grid is a simple average of all available daily grids for the month. Prior to 1955, there is one grid per day. From July 1962 on, there are two grids each day. In the interim period, the number of daily grids varies between one and two.

The grids for the period 1899-1977 were inspected and many corrections were made by Kevin Trenberth of the Laboratory of Atmospheric Research at the University of Illinois at Champaign-Urbana, and these grids are included in this dataset. For more information about these corrections, see the July 1980 issue of Monthly Weather Review.

This dataset contains once-daily Northern Hemisphere sea-level pressure data on a 10-degree by 5-degree (36x16) latitude/longitude grid for the period 1880 to 1979.

The gridded daily sea-level pressure analyses in this dataset were produced by the operational models of the U.S. Navy Fleet Numerical Oceanography Center (FNOC). The data are arranged in a 63x63 polar-stereographic grid covering the Northern Hemisphere for the period January 1946 to December 1993. DSS has produced a set of monthly grids from the dailies.

This dataset also includes daily 500mb geopotential height grids for the period January 1946 to December 1955 on the same polar-stereographic grid as the sea-level pressure data.

The daily sea-level pressure grids in this dataset were received from Steve Pazan of the U.S. Navy Fleet Numerical Oceanography Center (FNOC). The 63x63 polar-stereographic grids cover the period January 1946 to December 1978.

This dataset contains gridded Northern Hemisphere sea-level pressure and 500mb geopotential height data from the United Kingdom.

The DSS has converted the original daily 10-degree by 5-degree sea-level pressure grids to a 5-degree by 5-degree grid, interpolating data to non-original gridpoints and computing monthly grids. The period covered is December 1944 to December 1946.

The daily 500mb geopotential height grids cover the period from January 1945 to December 1946 on a 10-degree by 5-degree grid.

This dataset contains daily grids of dewpoint depression and cloud coverage for the period September 1963 to April 1972, provided by the U.S. Air Force Global Weather Central (AFGWC). Grids are available twice-daily at 12-hour intervals (00Z and 12Z). Dewpoint depression is available at four levels (850mb, 700mb, 500mb, and 400mb), as are low, middle, high, and total cloud coverage.

Also known as 3-D Nephanalyses

This dataset contains daily gridded Northern Hemisphere analyses from NMC's operational model on a 47x51 polar-stereographic grid centered on the North Pole. Available parameters include geopotential height, temperature, stream functions, thickness, and vertical velocity for various levels and layers through the troposphere. In general, the grids cover the period from January 1959 to December 1972, but periods for individual parameters will vary.

This dataset of daily gridded analyzed geopotential height and temperature for the Northern Hemisphere stratosphere covers the period from January 1946 to December 1980. The 47x51 polar-stereographic grids, centered on the North Pole, were produced by NMC's operational model.

For data beyond 1980, see ds067.0, which provides global coverage of the stratosphere on a pair of 63x63 polar-stereographic grids centered on each Pole.

This dataset contains Fourier wave analyses built from other DSS datasets.

This dataset contains various daily NMC forecast grids on a 47x51 Northern Hemisphere polar-stereographic grid centered on the North Pole. Grids on various tropospheric levels and layers contain parameters which include geopotential height, temperature, wind, surface and sea-level pressure, vertical motion, and stream functions, and they are available for sporadic periods between November 1967 and December 1971.

NMC operationally produced these daily gridded Northern Hemisphere analyses of various tropospheric levels for the period August 1963 to December 1972. Parameters include upper-level winds, surface temperature, sea-level pressure, tropopause pressure and temperature, and 500mb relative humidity on a 47x51 polar-stereographic grid centered on the North Pole.

This dataset contains various gridded Northern Hemisphere tropospheric analyses and 6-hour forecasts produced by NMC's operational model for the period October 1958 to December 1972. Vertical motion analyses at 650mb and 350mb are available for most of the period, and geopotential heights and thicknesses for for various levels and layers are available until January 1965. Six-hour forecasts of vertical motion cover the period from July 1966 to December 1972. The grid is a 47x51 polar-stereographic grid centered on the North Pole.

Originally the 47x51 grid was the one in which the B-3 analyses were done. These are now interpolated from the global analyses. Now NCEP interpolates the 65x65 grid from the global analyses. NCAR extracts the 47x51 subgrid (List A) from the full grid (List B).

More information is available.

DSS presents the Global Stratospheric Analyses on a pair of 65x65 polar grids. These were operationally prepared by NCEP daily, at 12Z.

The analyses are available on 8 mandatory levels from Parameters include pressure, geopotential height, temperature, and total column ozone.

This dataset is in the binary NMC Office Note 84 (ON84) format.

This dataset contains global once-daily and monthly-mean gridded analyses for September 1978 to February 1998, which were produced by NMC's operational models. At mandatory levels from 1000mb up to 0.4mb, grids contain geopotential height and temperature. At the tropopause, grids contain pressure and temperature. Also included are total column ozone and upward flux of longwave radiation.

The grid is a 65x65 polar-stereographic grid, centered on the Pole (North or South). Global coverage is provided by combining two grids, one for the Northern Hemisphere and one for the Southern Hemisphere.

The Flattery analysis method was used through 26 July 1984, so the usefulness of grids in that period is suspect. After that time, the analysis method used was the same as for other NMC global archives.

DSS presents the Global Stratospheric Analyses on a pair of 65x65 polar grids, daily at 12Z. These were operationally prepared by NCEP.

The analyses are available on 8 mandatory levels from 70 to 0.4 mb. Parameters include pressure, geopotential height, and temperature.

This dataset is in GRIB format. It is updated monthly using weekly files prepared for DSS by NCEP. The most current 12 months of data are available online through the DS067.3 data page.

This dataset contains once-daily global gridded geopotential height and temperature at levels from 1000mb up to 1mb for the period from April 1979 to May 1994. Bill Randel of NCAR interpolated bad and missing data in the grids of ds067.1 and stored the new data as zonal Fourier coefficients on an approximate 4.5 degree latitude/longitude grid (consistent with R15 spectral resolution). Further information can be found in NCAR Technical Note 366, which is available from the UCAR publications office at (303) 497-8601.

The products of NMC Eta model are archived in this dataset at spatial resolution of 40km with 38 vertical levels. This is the primary NMC mesoscale data archive over North America including Alaska.

This dataset contains the Limited Fine Mesh (LFM) model output from NCEP. The output contains initial time analyses and forecast fields from 6 hours out to 48 hours. These grids are no longer being produced by NCEP. The December, 1995 data is the last data we will archive from the LFM model.

Limited area NGM grids from NMC. Analyses and 6 hrly forecasts (to 48 hr) made each 12 hours. For North America. Same grid as for LFM.

This dataset contains the FSL MAPS analyses on their native (hybrid-b) coordinate system.

Analyses since 1983Jan were merely interpolated by NMC from the Global Analyses in DS082.0

Flattery's analysis scheme, using second version of Hough coefficients.

See DS081.0 for later analyses.

More information is available.

Flattery's global analysis scheme, using second version of Hough coefficients.

Later analyses, in NMC ON84 format, are in DS082.0. See DS080.0 for earlier analyses.

More information is available.

DSS presents the Global Final (FNL) Analyses on a pair of 2.5x2.5 degree hemispheric grids, every twelve hours. These were operationally prepared by NCEP. The NCAR documents Information about NMC Analysis and Forecast Models and History of Changes in the NMC Analysis Techniques discuss model features and changes.

The analyses are available on the surface, 12 mandatory levels from 1000mb to 50mb, boundary and some sigma layers, tropopause, and a few others. Parameters include surface pressure, sea level pressure, geopotential height, temperature, sea surface temperature, potential temperature, relative humidity, snow depth (weekly, Northern Hemisphere only) precipitable water, u- and v- winds and vertical motion.

This dataset is in the binary NMC Office Note 84 (ON84) format. DSS has prepared a set of GRIB formatted files which have a one-to-one correspondence to the ON84 formatted files. More information is available.

DSS presents a surface subset of the Global Final (FNL) Analyses on a pair of 2.5x2.5 degree hemispheric grids, every twelve hours. These were operationally prepared by NCEP. The NCAR documents Information about NMC Analysis and Forecast Models and History of Changes in the NMC Analysis Techniques discuss model features and changes.

The analyses are available on the surface, at 1000mb and a boundary layer. This subset was prepared by DSS from the analyses in DS082.0. Parameters include surface pressure, sea level pressure, geopotential height, temperature, sea surface temperature, potential temperature, relative humidity, snow depth (weekly, Northern Hemisphere only), and u- and v-winds.

This dataset is in the binary NMC Office Note 84 (ON84) format. More information is available.

NCEP Global Tropospheric Analyses on 145x37 2.5 degree grids, one for each hemisphere, 1976Jul01-1997Apr12. The Flattery analysis method was used through 1978Sep21. It forced a relationship between heights and winds which causes the zonal mean meridional wind at every level to be zero. This also caused other problems with winds in equatorial areas. The optimal analysis (OI) method (12 layer) started 1978Sep22. In 1985Apr the Medium Range Forecast (MRF) model started, with 18 layers. Analyses include geopotential height, temperature, wind (u- and v-components) and potential temperature. In more recent years the temperature analyses are derived from thickness temperatures.

NCEP Global Analyses on 145x37 2.5 degree grids, one for each hemisphere. Has surface, tropospheric, tropopause, and lower stratospheric analyses; at mandatory levels up to 50mb. More... This is a subset of the data in DS082.0.and is identical except that it is in GRIB format on CD-ROM in. Every CDROM contains six months of data.

DSS presents the Global Final (FNL) Analyses on a pair of 2.5x2.5 degree hemispheric grids every twelve hours. These were operationally prepared by NCEP. The NCEP documents About the Global Parallel System and EMC Model Documentation describe the model.

The analyses are available on the surface, 16 mandatory levels from 1000mb to 10mb, boundary layer and some sigma layers, tropopause, and a few others. Parameters include surface pressure, sea level pressure, geopotential height, temperature, sea surface temperature, soil temperature, water content of soil, ice cover, water equivalent of snow depth, relative humidity, specific humidity, u- and v-wind components, vertical motion, vorticity, precipitable water, minimum temperature, maximum temperature and land-sea mask

This dataset is in GRIB format. It is updated monthly using weekly files prepared for DSS by NCEP. The most current 12 months of data are available online through the DS083.0 data page. Information about using the data is here.

DSS presents a surface subset of the Global Final (FNL) Analyses on a pair of 2.5x2.5 degree hemispheric grids, every twelve hours. These were operationally prepared by NCEP. The NCEP documents About the Global Parallel System and EMC Model Documentation describe the model.

The analyses are available on the surface, at 1000mb and a boundary layer. This subset was prepared by DSS from the analyses in DS083.0. Parameters include surface pressure, sea level pressure, geopotential height, temperature, sea surface temperature, soil temperature, water content of soil, ice cover, water equivalent of snow depth, relative humidity, specific humidity, u- and v-wind components, minimum temperature, maximum temperature and land-sea mask

This dataset is in GRIB format. It is updated irregularly. Information about using the data is here.

DSS presents the Global Final (FNL) Analyses on 1.0x1.0 degree grids covering the entire globe every six hours. These were operationally prepared by NCEP. The NCEP documents About the Global Parallel System and EMC Model Documentation describe the model. For questions about the science of the FNL, contact the NCEP Science Liaison.

The analyses are available on the surface, 26 mandatory (and other pressure) levels from 1000mb to 10mb, boundary and some sigma layers, tropopause and a few others. Parameters include surface pressure, sea level pressure, geopotential height, temperature, sea surface temperature, soil values, ice cover, relative humidity, u- and v- winds, vertical motion, vorticity and ozone.

This dataset is in GRIB format. It is updated every 6 hours by DSS using files downloaded from the NCEP server. The most current 12 months of data are available online through the DS083.2 data page. Information about using the data is here.

10 day forecasts at 12 hour intervals from MRF model in spherical harmonics at R30 through 1995Nov beginning 1995Dec, on 2.5 deg grid in GRIB

Analyses from the MRF on 18 or 23 sigma levels in spherical harmonic representation

Fields from MRF analyses, four times per day, plus 12-, 24- and 36-hour forecasts.

This dataset contains a time-series collection of monthly gridded Northern Hemisphere tropospheric data on a 47x51 polar stereographic grid. This collection has been assembled by DSS from the daily grids of various operational models and meteorological projects.

This dataset contains a time-series collection of monthly mean gridded Northern Hemisphere tropospheric data on a 5-degree latitude/longitude grid. This collection was assembled and computed by DSS from the daily grids of various operational models and meteorological projects. The daily grids are located in ds195.1.

This dataset contains a time-series collection of monthly Northern Hemisphere tropospheric data on a 2.5-degree latitude/longitude grid. These grids were created by DSS from the grids of ds085.0, which have a resolution of five degrees. The intermediate points of the grids in this set were interpolated from the existing surrounding gridpoints using a 16-point Bessel interpolation scheme.

This dataset contains monthly means of several meteorological variables, their squares, and their cross-products for nine levels in the atmosphere. These mean grids were prepared by the Climate Analysis Center (CAC) from NMC daily analyses. The grid is a 2.5 degree grid (145x37) for each hemisphere, so that data are available globally.

72x19 hemispheric grids, 8 levels, temperature and height

Products from NCEP/NCAR Reanalysis Project (NNRP or R1) are archived in this dataset. The resolution of the global Reanalysis Model is T62 (209 km) with 28 vertical sigma levels. Results are available at 6 hour intervals. Although the initial plan is to reanalyze the data for a 40-year period (1957-1996), production has gone back to 1948 and going forward continuously. Future plans call for rerunning the entire period as next generation models are ready.

There are over 80 different variables, (including geopotential height, temperature, relative humidity, U and V wind components, etc.) in several different coordinate systems, such as 17 pressure level stack on 2.5x2.5 degree grids, 28 sigma level stack on 192x94 Gaussian grids, and 11 isentropic level stack on 2.5x2.5 degree grid. They are organized as different subgroups in the archive. In addition to analyses, diagnostic terms (for example: radiative heating, convective heating) and accumulative variables (like precipitation rate) are present. The input observations are archived with quality/usage flags in WMO BUFR format. Most of the project outputs are stored in WMO GRIB format. Other files, such as restart files and zonal statistics, are saved in IEEE format.

Some special periods are analyzed more than once to provide data for special research studies. For example, a special NOSAT run of 1979 was made excluding most satellite inputs. This run could be used for evaluating the impact of satellite data on the analysis. During TOGA-COARE experiment period, special runs of reanalysis model without (NOEXP) experimental data are archived under TOGA-COARE directory.

For details and problems, see NCEP/NCAR Reanalysis. Monthly means are on line at ds090.2. The R1 forecasts are in ds090.1 dataset.

This data set contains forecast products from the NCEP/NCAR Reanalysis Project. The resolution of the Reanalysis Forecast Model is T62 (209 km) with 28 vertical sigma levels. Every five days, beginning with 00Z 01 January, an 8 day forecast run is made. The initial time and outputs for every 12 hours are saved from this run. Pressure level and special level data are archived on the 2.5x2.5 latitude-longitude grid and flux fields are archived on the 192x94 Gaussian grid. Details on variables included are available elsewhere. Some special periods will be analyzed more than once to provide data for special research studies. For example, a special NOSAT run of 1979 was made excluding most satellite inputs. This run could be used for evaluating the impact of satellite data on the forecasts. See DS090.0for analysis and first guess fields. All data files of 1948-2005OCT are available as of 2005DEC29.

The monthly means of NCEP/NCAR Reanalysis (R1) products, archived in ds090.0 dataset, are extracted and reorganized into 10 subgroups in this dataset. The 10 subgroups are: dgn, presA, presB, theta, xprod, 00Z, 06Z, 12Z, 18Z and rest subgroups. The monthly means of diagnostic terms, (such as various heating terms, convective moistening rate, etc.) are in the dgn subgroup. The presA subgroup contains most commonly used parameters, like geopotential height, temperature, U and V winds, relative humidity, at all 17 pressure levels. The presB subgroup has the remaining variables on pressure levels. The theta subgroup includes all variables on isentropic levels. The xprod contains cross products of variables at pressure levels. The 00Z, 06Z, 12Z and 18Z subgroups have monthly means computed from those individual hours only. Monthly means of flux terms (like wind at 10m, temperature at 2m, etc) and accumulative variables (like precipitation rate, precipitable water, etc.) are in the rest subgroup.

The data files are in WMO GRIB format. Both the monthly means and their variances are in the same file but in different GRIB records. Examples of separating monthly means from variances are shown in how2use_grads.txt.

All subgroups will be available on line under data. The ones that are not on line yet will be moved over upon request.

This dataset contains products from the NCEP/DOE Reanalysis II (R2) Project. The resolution of the R2 model is the same as NCEP/NCAR Reanalysis (R1) proejct, T62 (209 km) with 28 vertical sigma levels. The output fields are saved 4 times a day as in R1. The main objective of the R2 project is to correct known errors in the R1 project and update the parameterizations of the physical processes. Improvements are seen in surface flux fields, hydrological budget, short wave radiation flux, etc. There are also drawbacks found in the outgoing longwave radiation over tropical warm pool and upper-level tropical moisture. R2 plans to reanalyze the data starting from 1979 and going forward only.

The main R2 products archived at NCAR consitute of 6 subgroups: pressure level analysis (pgb-anl), sigma level analysis (sgb-anl), flux term analysis (flx-ft00), diagnostic analysis (dg3-ft00) and 6-hour forecasts of flux term (flx-ft06) and diagnostic (dg3-ft06) terms. All data files are in GRIB format and archived by month.

This dataset is updated once a month. Most commonly used fields are also available at NCEP's NCEP NOMAD Server. Climate Diagnostic Center (CDC) of NOAA has the same data in netCDF format at CDC Reanalysis 2.

This dataset contains various grids created by DSS to make comparisons of the outputs of Reanalysis vs. Reanalysis and Reanalysis vs. other operational models.

This dataset contains gridded sea-level pressure data for the Southern Hemisphere for January 1951 to December 1958. The grid is a 5-degree latitude longitude grid that covers the hemisphere from 15S to the South Pole.

The data came to DSS originally from South Africa, where it was on a diamond latitude/longitude grid (10-degree longitude resolution by 5-degree latitude resolution) for most of the period. DSS interpolated, where possible, data to the original missing points to provide a 5-degree resolution in both directions.

The grids in this dataset contain Southern Hemisphere sea-level pressure and 500mb height data for the International Geophysical Year (IGY) period of June 1957 to December 1958. The data are on a 5-degree latitude/longitude grid covering the hemisphere from 15S to the South Pole.

The data originally came from South Africa where it was on a 10-degree by 5-degree diamond latitude/longitude grid. DSS interpolated data to the missing gridpoints to provide a resolution of five degrees in both directions.

This dataset contains a time-series of sea-level pressure data on a 63x63 polar-stereographic grid over the Southern Hemisphere. These grids were subsetted from the Navy grids in ds240.6 and cover the period from August 1974 to June 1983.

This dataset contains sea-level pressure data on a 5-degree latitude/longitude grid over the global tropics from 25S to 25N. The time period covered by the data is for the International Geophysical Year (IGY) of June 1957 to December 1958.

From the Republic of South Africa Weather Bureau, twice daily Southern Hemisphere grids on a polar stereographic projection.

From the Australian National Meteorological Research Centre, twice daily Southern Hemisphere grids on a polar stereographic projection. DSS derived the monthly mean grids. Later and ongoing data may be available directly from ABM.

This dataset contains 500mb heights for the Southern Hemisphere for the period June 1968 to August 1977. The grid has a resolution of 10 degrees in the longitudinal direction and 5 degrees in the latitudinal direction and covers the hemisphere from 15S to the South Pole.

The data were received from the Australian Numerical Meteorology Research Centre.

This dataset contains gridded sea-level pressure data that covers the area around New Zealand. The grid is a 16x16 grid over the area from 5S to 80S and 60E to 150W, with a resolution of five degrees in latitude and ten degrees in longitude. For the period from June 1957 to February 1958, the sea-level pressures were extracted from the 00Z meteorological charts.

From European Centre for Medium Range Weather Forecasts (ECMWF), twice daily grids. Monthly mean grids derived in U.S.

The ECMWF analyses for 1980-1989 were used to derive a global year-month wind stress climatology. Several climate monthly mean grids were also formed. Wind component grids are also available as are standard deviation grids for each variable computed.

The ECMWF analyses for 1980-1989 were used to derive global long term means.

The ds111.n collection of datasets archives output from ECMWF's daily operational global numerical model. Dataset ds111.0 contains geopotential, temperature, wind, and moisture fields on constant pressure levels, starting in 1985. The horizontal resolution of the DSS archive is T106 spectral resolution in spherical harmonics, however, in later years, the model is actually run at a much higher resolution (T511 as of 2001). All fields are output 4x a day at 00Z, 06Z, 12Z and 18Z. This dataset is updated twice a year. ECMWF maintains an online description of its operational model and its evolution.

The surface data can be found in ds111.1 and the supplemental fields inlcuding radiation,stress and flux terms are in ds111.3. The model precipitation is archived in ds111.6. The ECMWF operational model output on the 2.5 degree latitude-longitude grid can be found in ds111.2.

This dataset contains the high resolution output from the ECMWF operational model. This set contains only surface data on a gaussian (n80) grid with a resolution of about 1.125 degrees.

ECMWF now has a description of its operational model and its evolution online.

This dataset contains 2.5 degree latitude-longitude output grids from the ECMWF operational model. Both upper air and surface grids are archived in this dataset.

ECMWF now has a description of its operational model and its evolution.

This dataset contains supplementary output grids from the ECMWF operatoinal model. These grids are on a gaussian grid (n80) with approximtely a 1.125 degree resolution.

ECMWF now has a description of its operational model and its evolution online.

ECMWF now has a description of its operational model and its evolution online.

These are year-month means on 2.5 degree grids derived from DS111.2, by DSS. Both surface and upper air. Bad grids found by Kevin Trenberth in TN-373 are excluded.

ECMWF now has a description of its operational model and its evolution online.

This dataset contains various output grids from the ECMWF operational model. All of the grids are on a gaussian (n80) grid with a resolution of approximately 1.125 degrees daily accumulations from forecast hours 12 - 36 of 12Z run.

ECMWF now has a description of its operational model and its evolution online.

As part of a data exchange involving climate data, DSS received various global and hemispheric gridded analyses from the U.S.S.R. The analyses include a long time series of Northern Hemisphere surface pressure spanning the period 1880-1979, global total cloud amount for 1966-1985, and surface temperature, sea-level pressure, and upper-level geopotential heights for the overarching period of 1948-1984 (actual periods vary by parameter and atmospheric level).

This dataset contains surface grids from the ECMWF 15 year Reanalysis Project. All grids are on a 2.5 degree latitude- longitude grid and are archived 4x/day.

This dataset contains upper air grids from the ECMWF 15 year Reanalysis Project. All grids are on a 2.5 degree latitude- longitude grid and are archived 4x/day.

This dataset contains the supplementary fields from the ECMWF 15 year reanalysis project. All fields are on a 2.5 degree latitude-longitude grid and are accumlations derived from forecast grids.

This dataset contains the high resolution surface grids from the ECMWF 15 year reanalysis project. All of the grids are on a gaussian (N80) grid with an approximate resolution of 1.125 degrees and are archived 4x/day.

This dataset contains the high resolution uppper air grids from the ECMWF 15 year reanalysis project. All of the grids are in spherical harmonic representation (t106) which can be gridded to about of 1.125 degrees.

This dataset contains high resolution supplementary grids from the ECMWF reanalysis project. The grids are all on a reduced gaussian (n80) grid with an approximate resolution of 1.125 degrees. This fields are all derived from forecasts.

This dataset contains high resolution moisture grids from the ECMWF reanalysis project. The grids are all on a reduced gaussian (n80) grid with an approximate resolution of 1.125 degrees.

This dataset contains monthly mean data from the ECMWF reanalysis project. The grid are all 2.5 degree latitude-longitude grids. There are separate monthly means for each hour (00,06,12 and 18) as well as a daily mean.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset has been segmented into 4 archives:

• Surface - 46 mostly surface and near surface fields, including 10m wind, 2m air temp, soil temp and moisture, cloud cover info
• Vertical Integrals - 35 fields including column water vapor, column ozone, kinetic energy
• Other - 27 fields, including precip, fluxes, radiation, stresses
• LNSP - Log of the surface pressure

This dataset contains ECMWF ERA40 model output consisting of geopotential, temperature, wind and moisture variables on 23 constant pressure surfaces for the period September, 1957 to August, 2002. All variables, except moisture, are archived at global T159 spectral resolution in spherical harmonics, while the moisture is archived on a reduced N80 gaussian grid with an approximate horizontal resolution of 150 kilometers. All data are archived 4x daily at 00z, 06z, 12z and 18z. All data is in GRIB format.

The ECMWF ERA40 project is a global atmospheric analysis of many conventional observations and satellite data streams for the period September,1957- August,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and possible research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 9 variables on the original 60 model levels, as well as surface geopotential and log of surface pressure. Variables are archived at T159 spectral resolution in spherical harmonics or the reduced n80 gaussian grid with a resolution of approximately 125 kilometers. All variables are output 4x a day for the entire period.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 7 variables on 15 isentropic surfaces. Some of the variables are on a T159 spherical harmonics grid and some are on the N80 reduced gaussian grid. All variables are output 4x a day for the entire period.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 7 variables on the PV+-2 surface. All of the variables are on the N80 reduced gaussian grid. All variables are output 4x a day for the entire period.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 4 variables on the original 60 hybrid model levels on the reduced N80 Gaussian grid. The data are accumulated over the 3 and 6 hour forecasts for the 00, 06, 12 and 18 UTC analyses.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains the Net tendencies from parameterized processeses. There are 4 variables in this dataset, each of which are on the original 60 hybrid model levels on the reduced N80 Gaussian grid. The data are accumulated over the 3 and 6 hour forecasts for the 00, 06, 12 and 18 UTC analyses.

This dataset contains 56 surface and single level variables on an equally spaced global 2.5 degree latitude-longitude grid. All variables are reported 4x a day.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 11 variables on 23 pressure surfaces on an equally spaced global 2.5 degree latitude-longitude grid. All variables are reported 4x a day for the entire period.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset has been segmented into 3 archives:

• Surface - 47 mostly surface and near surface fields, including 10m wind, 2m air temp, soil temp and moisture, cloud cover info
• Vertical Integrals - 35 fields including column water vapor, column ozone, kinetic energy
• Accumulated (other) Fields - 27 fields including precip, fluxes, radiation, stresses

Monthly means have been computed for each analysis hour as well as a daily mean.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains monthly means for 9 variables on 23 pressure surfaces at T159 spectral resolution in spherical harmonics. Monthly means have been computed for each analysis hour as well as a daily mean.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains monthly means for 9 variables on the original 60 model levels, as well as surface geopotential and log of surface pressure. Variables are archived at T159 spectral resolution in spherical harmonics or the reduced n80 gaussian grid with a resolution of approximately 125 kilometers. All variables are output 4x a day for the entire period. Monthly means have been computed for each analysis hour as well as a daily mean.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains monthly means for 7 variables on 15 isentropic surfaces. Some of the variables are on a T159 spherical harmonics grid and some are on the N80 reduced gaussian grid. Monthly means have been computed for each analysis hour as well as a daily mean.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains monthly means for 7 variables on the PV+-2 surface. All of the variables are on the N80 reduced gaussian grid. All variables are output 4x a day for the entire period.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains variances and covariances on the original 60 model levels, as well as the variance of the surface pressure. All Variables are archived on the full n80 gaussian grid with a resolution of approximately 125 kilometers. The variances and covariances are produced with respect to the monthly means for each hour four synoptic hours (00, 06, 12 and 18 UTC) and for the diurnal mean.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains monthly means of the ERA40 2.5 dergree latitude-longitude gridded surface and single level analysis. Monthly means have been computed for each analysis hour as well as a daily mean.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 11 variables on 23 pressure surfaces on an equally spaced global 2.5 degree latitude-longitude grid. Monthly means have been computed for each analysis hour as well as a daily mean.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 75 variables from the from the forecast cycle of the ERA-40 model. The forecasts extend out to 36 hours beginning from the 00 and 12 UTC analyses and out to 6 hours beginning with the 06 and 18 UTC analyses. The analysis fields have been archived in ds117.0. All data are archived on an N80 reduced gaussian grid 4x a day.

This dataset contains ECMWF ERA40 model forecasts of geopotential, temperature, wind and moisture variables on 23 constant pressure surfaces for the period September, 1957 to August, 2002. The forecasts extend out to 36 hours beginning from the 00 and 12 UTC analyses and out to 6 hours beginning with the 06 and 18 UTC analyses. All variables, except moisture, are archived at global T159 spectral resolution in spherical harmonics, while the moisture is archived on a reduced N80 gaussian grid with an approximate horizontal resolution of 125 kilometers. The anlaysis fields have been archived in ds117.1.

The ECMWF ERA40 project is a global atmospheric analysis of many conventional observations and satellite data streams for the period September,1957- August,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and possible research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available

This dataset contains 9 variables on the original 60 model levels, as well as surface geopotential and log of surface pressure. All Variables are from the forecast cycle of the ERA-40 model and are archived at T159 spectral resolution in spherical harmonics or the reduced n80 gaussian grid with a resolution of approximately 125 kilometers. The forecasts extend out to 36 hours beginning from the 00 and 12 UTC analyses and out to 6 hours beginning with the 06 and 18 UTC analyses. The anlaysis fields have been archived in ds117.2.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains monthly means for 73 surface and single level variables from the forecast cycle of the ERA40 model. Means are available for the 3 and 6 hour forecasts for each synoptic hour (00, 06, 12 and 18 UTC) as well as a diurnal mean for the 6 hour forecast.

Monthly means have been computed for each analysis hour as well as a diurnal mean.

This dataset contains ECMWF ERA40 monthly mean model forecasts of geopotential, temperature, wind and moisture variables on 23 constant pressure surfaces for the period September, 1957 to August, 2002. The means have been computed for the 6 hour forecast only. All variables are archived at global T159 spectral resolution in spherical harmonics, except the moisture, ozone and potentical vorticity, which are archived on a reduced N80 gaussian grid with an approximate horizontal resolution of 125 kilometers. The monthly mean analysis fields have been archived in ds119.1.

The ECMWF ERA40 project is a global atmospheric analysis of many conventional observations and satellite data streams for the period September,1957- August,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and possible research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains monthly means for 9 variables on the original 60 model levels, as well as surface geopotential and log of surface pressure. Variables are archived at T159 spectral resolution in spherical harmonics or the reduced n80 gaussian grid with a resolution of approximately 125 kilometers. Synoptic monthly means have been computed for each analysis hour and a diurnal mean has also been computed. Both means are only computed for the 6 hour forecast.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 23 variables from the ERA40 WAVE model on an equally spaced global 1.5 degree latitude-longitude grid . All variables are reported 4x a day.

There has been a problem with the wave analysis since the introduction of ERS data at the start of 1991. The size of waves of low magnitude (less than 1 metre) may be too high and the corresponding mean periods too high. The problem is largely confined to enclosed or semi-enclosed seas such as the Mediterranean Sea, Black Sea, Baltic Sea, the Gulf of Mexico and the East China Sea.

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 23 variables from the ERA40 WAVE model on an equally spaced global 1.5 degree latitude-longitude grid . All variables are reported 4x a day.

DS124.0 represents a dataset implemented and computed by NCAR's Data Support Section, and forms an essential part of efforts undertaken in late 2004, early 2005, to produce an archive of selected segments of ERA-40 on a standard transformation grid.

In this case, forty six ERA-40 6-hourly surface and single level analysis variables were transformed from a reduced N80 Gaussian grid to a 256x128 regular Gaussian grid. (These are designated as "SURFACE", or "SURFACE/SINGLE LEVEL", or "SFC/sfc", variables below.) All fields were transformed using routines from the ECMWF EMOS library, including 10 meter winds which were treated as scalars because of a lack of 10 meter spectral vorticity and divergence. A missing value of 9.999e+20 occurs in the sea surface temperature and sea ice (SSTK and CI) fields to mask grid points occurring over land. Fields formerly archived as whole integers, such as vegetation indices and cloud cover, occur as integers plus a fractional part in the T85 version due to interpolation.

In addition, twenty seven ERA-40 6-hourly surface and single level 6-hour forecast variables were transformed from a reduced N80 Gaussian grid to a 256x128 regular Gaussian grid. (These are designated as "OTHER", or "othr", variables below.) All variables are valid 6 hours after the forecast was initiated. Thus, 00Z 6-hour forecast evaporation is valid at 06Z. Four of the variables are "instantaneous" variables, and the remaining twenty three variables are "accumulated" over the 6-hour forecast time. Divide the accumulated variables by 21600 seconds to obtain instantaneous values. (Multiplication by minus one may also be necessary to match the sign convention one is accustomed to.) All fields were transformed using routines from the ECMWF EMOS library, including three pairs of stresses which were treated as scalars because of a lack of spectral precursors.

The choice of a T85 Gaussian grid was based on considerations of limiting the volume of new data generated to a moderate level, and to match the horizontal resolution of the Community Atmosphere Model (CAM) component of NCAR's Community Climate System Model (CCSM).

The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

DS124.1 represents a new data set implemented and computed by NCAR's Data Support Section, and forms a substantial part of ongoing efforts to produce an archive of selected segments of ERA-40 on a standard transformation grid. In this case, ERA-40 upper air variables on 23 pressure levels have been transformed from either spherical harmonics (geopotential, temperature, vertical pressure velocity, vorticity, divergence, relative humidity), or a reduced N80 Gaussian grid (potential vorticity, specific humidity, ozone mass mixing ratio), to a 256x128 regular Gaussian grid at T85 spectral truncation. In addition, horizontal wind components have been derived from spectral vorticity and divergence and also archived on a T85 Gaussian grid. All scalar fields have been transformed using routines from the ECMWF EMOS library, whereas the horizontal winds have been obtained using NCAR's Spherepack library. The choice of a T85 Gaussian grid was based on considerations of limiting the volume of new data generated to a moderate level, and to match the horizontal resolution of the Community Atmosphere Model (CAM) component of NCAR's Community Climate System Model (CCSM).

Sub-setting of DS124.1 is available to registered users of DSS ERA-40 data. Users may select a set of variables, and designate pressure levels, and start and end dates, for each variable. Output, in GRIB or netCDF, can be retrieved via restricted ftp.

DS124.2 represents a dataset implemented and computed by NCAR's Data Support Section, and forms an essential part of efforts undertaken in late 2004, early 2005, to produce an archive of selected segments of ERA-40 on a standard transformation grid. In this case, ERA-40 6-hourly upper air variables on 60 model levels were transformed from either spherical harmonics (surface geopotential, temperature, vertical velocity, vorticity, logarithm of surface pressure, divergence), or a reduced N80 Gaussian grid (specific humidity, ozone mass mixing ratio, cloud liquid water content, cloud ice water content, cloud cover), to a 256x128 regular Gaussian grid at T85 spectral truncation. In addition, horizontal wind components were derived from spectral vorticity and divergence and also archived on a T85 Gaussian grid. All scalar fields were transformed using routines from the ECMWF EMOS library, whereas the horizontal winds were obtained using NCAR's Spherepack library. The choice of a T85 Gaussian grid was based on considerations of limiting the volume of new data generated to a moderate level, and to match the horizontal resolution of the Community Atmosphere Model (CAM) component of NCAR's Community Climate System Model (CCSM).

DS126.0 represents a dataset implemented and computed by NCAR's Data Support Section, and forms an essential part of efforts undertaken in late 2004, early 2005, to produce an archive of selected segments of ERA-40 on a standard transformation grid.

In this case, forty seven ERA-40 monthly mean (designated as "MODA" or "moda" below) surface and single level analysis variables were transformed from a reduced N80 Gaussian grid to a 256x128 regular Gaussian grid. (These are further designated as "SURFACE", or "SURFACE/SINGLE LEVEL", or "SFC/sfc", variables below.) All fields were transformed using routines from the ECMWF EMOS library, including 10 meter winds which were treated as scalars because of a lack of 10 meter spectral vorticity and divergence. A missing value of 9.999e+20 occurs in the sea surface temperature and sea ice (SSTK and CI) fields to mask grid points occurring over land. Fields formerly archived as whole integers, such as vegetation indices and cloud cover, occur as integers plus a fractional part in the T85 version due to interpolation.

Twenty seven ERA-40 monthly mean (designated as "MODA" or "moda" below) surface and single level 6-hour forecast variables were transformed from a reduced N80 Gaussian grid to a 256x128 regular Gaussian grid. (These are further designated as "OTHER", or "othr", variables below.) Four of the variables are "instantaneous" variables, and the remaining twenty three variables are "accumulated" over the 6-hour forecast time. Divide the accumulated variables by 21600 seconds to obtain instantaneous values. (Multiplication by minus one may also be necessary to match the sign convention one is accustomed to.) All fields were transformed using routines from the ECMWF EMOS library, including three pairs of stresses which were treated as scalars because of a lack of spectral precursors.

In addition, all corresponding 00Z, 06Z, 12Z, and 18Z monthly mean surface and single level analysis variables and 6-hour forecast variables were also transformed to a T85 Gaussian grid (designated as "MNLY", "mnly", or "mnth" below)

All forecast variables are valid 6 hours after the forecast was initiated. Thus, 00Z 6-hour forecast evaporation is valid at 06Z. Divide the accumulated variables by 21600 seconds to obtain instantaneous values. (Multiplication by minus one may also be necessary to match the sign convention one is to.)

The choice of a T85 Gaussian grid was based on considerations of limiting the volume of new data generated to a moderate level, and to match the horizontal resolution of the Community Atmosphere Model (CAM) component of NCAR's Community Climate System Model (CCSM).

DS126.1 represents a dataset implemented and computed by NCAR's Data Support Section, and forms an essential part of efforts undertaken in late 2004, early 2005, to produce an archive of selected segments of ERA-40 on a standard transformation grid. In this case, ERA-40 monthly mean upper air variables (designated as “MODA” or “moda” below) on 23 pressure levels were transformed from either spherical harmonics (geopotential, temperature, vertical pressure velocity, vorticity, divergence, relative humidity), or a reduced N80 Gaussian grid (potential vorticity, specific humidity, ozone mass mixing ratio), to a 256x128 regular Gaussian grid at T85 spectral truncation. In addition, horizontal wind components were derived from spectral vorticity and divergence and also archived on a T85 Gaussian grid. All scalar fields were transformed using routines from the ECMWF EMOS library, whereas the horizontal winds were obtained using NCAR's Spherepack library. All corresponding 00Z, 06Z, 12Z, and 18Z monthly mean upper air variables on 23 pressure levels were also transformed to a T85 Gaussian grid (designated as “MNLY”, “mnly”, or “mnth” below). The choice of a T85 Gaussian grid was based on considerations of limiting the volume of new data generated to a moderate level, and to match the horizontal resolution of the Community Atmosphere Model (CAM) component of NCAR's Community Climate System Model (CCSM).

DS126.2 represents a dataset implemented and computed by NCAR's Data Support Section, and forms an essential part of efforts undertaken in late 2004, early 2005, to produce an archive of selected segments of ERA-40 on a standard transformation grid. In this case, ERA-40 monthly mean upper air variables (designated as “MODA” or “moda” below) on 60 model levels were transformed from either spherical harmonics (surface geopotential, temperature, vertical pressure velocity, vorticity, logarithm of surface pressure, divergence), or a reduced N80 Gaussian grid (specific humidity, ozone mass mixing ratio, cloud liquid water content, cloud ice water content, cloud cover), to a 256x128 regular Gaussian grid at T85 spectral truncation. In addition, horizontal wind components were derived from spectral vorticity and divergence and also archived on a T85 Gaussian grid. All scalar fields were transformed using routines from the ECMWF EMOS library, whereas the horizontal winds were obtained using NCAR's Spherepack library. All corresponding 00Z, 06Z, 12Z, and 18Z monthly mean upper air variables on 60 model levels were also transformed to a T85 Gaussian grid (designated as “MNLY”, “mnly”, or “mnth” below). The choice of a T85 Gaussian grid was based on considerations of limiting the volume of new data generated to a moderate level, and to match the horizontal resolution of the Community Atmosphere Model (CAM) component of NCAR's Community Climate System Model (CCSM).

DS127.0 represents a dataset implemented and computed by NCAR's Data Support Section, and forms an essential part of efforts undertaken in late 2004, early 2005, to produce an archive of selected segments of ERA-40 on standard transformation grids.

In this case, forty six ERA-40 6-hourly surface and single level analysis variables were transformed from a reduced N80 Gaussian grid to a 320x160 regular Gaussian grid. (These are designated as “SURFACE”, or “SURFACE/SINGLE LEVEL”, or “SFC/sfc”, variables below.) All fields were transformed using routines from the ECMWF EMOS library, including 10 meter winds which were treated as scalars because of a lack of 10 meter spectral vorticity and divergence. A missing value of 9.999e+20 occurs in the sea surface temperature and sea ice (SSTK and CI) fields to mask grid points occurring over land. Fields formerly archived as whole integers, such as vegetation indices and cloud cover, occur as integers plus a fractional part in the T106 version due to interpolation.

In addition, twenty seven ERA-40 6-hourly surface and single level 6-hour forecast variables were transformed from a reduced N80 Gaussian grid to a 320x160 regular Gaussian grid. (These are designated as “OTHER”, or “othr”, variables below.) All variables are valid 6 hours after the forecast was initiated. Thus, 00Z 6-hour forecast evaporation is valid at 06Z. Four of the variables are “instantaneous” variables, and the remaining twenty three variables are “accumulated” over the 6-hour forecast time. Divide the accumulated variables by 21600 seconds to obtain instantaneous values. (Multiplication by minus one may also be necessary to match the sign convention one is accustomed to.) All fields were transformed using routines from the ECMWF EMOS library, including three pairs of stresses which were treated as scalars because of a lack of spectral precursors.

DS127.1 represents a higher resolution version of ds124.1. Both ds124.1 and 127.1 were implemented and computed by NCAR's Data Support Section, and form an essential part of efforts undertaken in late 2004, early 2005, to produce an archive of selected segments of ERA-40 on a standard transformation grid. In the case of ds127.1, ERA-40 6-hourly upper air variables on 23 pressure levels were transformed from either spherical harmonics (geopotential, temperature, vertical pressure velocity, vorticity, divergence, relative humidity), or a reduced N80 Gaussian grid (potential vorticity, specific humidity, ozone mass mixing ratio), to a 320x160 regular Gaussian grid at T106 spectral truncation. In addition, horizontal wind components were derived from spectral vorticity and divergence and also archived on a T106 Gaussian grid. All scalar fields were transformed using routines from the ECMWF EMOS library, whereas the horizontal winds were obtained using NCAR's Spherepack library.

DS127.2 represents a dataset implemented and computed by NCAR's Data Support Section, and forms an essential part of efforts undertaken in late 2004, early 2005, to produce an archive of selected segments of ERA-40 on standard transformation grids. In this case, ERA-40 6-hourly upper air variables on 60 model levels were transformed from either spherical harmonics (surface geopotential, temperature, vertical velocity, vorticity, logarithm of surface pressure, divergence), or a reduced N80 Gaussian grid (specific humidity, ozone mass mixing ratio, cloud liquid water content, cloud ice water content, cloud cover), to a 320x160 regular Gaussian grid at T106 spectral truncation. In addition, horizontal wind components were derived from spectral vorticity and divergence and also archived on a T106 Gaussian grid. All scalar fields were transformed using routines from the ECMWF EMOS library, whereas the horizontal winds were obtained using NCAR's Spherepack library.

DS129.1 represents a higher resolution version of ds126.1. Both ds126.1 and 129.1 were implemented and computed by NCAR's Data Support Section, and form an essential part of efforts undertaken in late 2004, early 2005, to produce an archive of selected segments of ERA-40 on a standard transformation grid. In the case of ds127.1, ERA-40 monthly mean upper air variables (designated as “MODA” or “moda” below) on 23 pressure levels were transformed from either spherical harmonics (geopotential, temperature, vertical pressure velocity,