ERA40 T85 Monthly Mean Analysis Fields on Model Levels, created at NCAR
d126002
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 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 256 by 128 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. 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) [https://www.cesm.ucar.edu/models/atm-cam/] component of NCAR's Community Climate System Model (CCSM). The ERA-Interim data from ECMWF is an update to the ERA-40 project. The ERA-Interim data starts in 1989 and has a higher horizontal resolution (T255, N128 nominally 0.703125 degrees) than the ERA-40 data (T159, N80 nominally 1.125 degrees). ERA-Interim is based on a more current model than ERA-40 and uses 4DVAR (as opposed to 3DVAR in ERA-40). ECMWF will continue to run the ERA-Interim model in near real time through at least 2010, and possibly longer. This data is available in ds627.0 [https://rda.ucar.edu/datasets/ds627.0/].
dataset
https://gdex.ucar.edu/datasets/d126002/
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applicationProfile: browser
name: Dataset Description
description: Related Link
function: information
https://gdex.ucar.edu/datasets/d126002/dataaccess/
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applicationProfile: browser
name: Data Access
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function: download
climatologyMeteorologyAtmosphere
dataset
revision
2014-10-16
ERA40DAS > ERA40 Data Assimilation System
MODELS > MODELS
revision
2025-09-19
ERA40 > ECMWF ERA40 Reanalysis Project
revision
2025-09-19
EARTH SCIENCE > ATMOSPHERE > CLOUDS > CLOUD MICROPHYSICS > CLOUD LIQUID WATER/ICE
EARTH SCIENCE > ATMOSPHERE > AIR QUALITY > TROPOSPHERIC OZONE
EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WATER VAPOR > WATER VAPOR INDICATORS > HUMIDITY
EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WINDS > UPPER LEVEL WINDS
EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WINDS > WIND DYNAMICS > VERTICAL WIND VELOCITY/SPEED
EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WINDS > WIND DYNAMICS > VORTICITY
EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC TEMPERATURE > UPPER AIR TEMPERATURE
EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WINDS > WIND DYNAMICS > CONVERGENCE
EARTH SCIENCE > ATMOSPHERE > CLOUDS > CLOUD PROPERTIES > CLOUD FREQUENCY
EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC PRESSURE > SURFACE PRESSURE
revision
2025-09-19
-180
180
88.928
-88.928
1957-09-01T00:00:00Z
2002-08-31T18:00:00Z
publication
2005-05-04
notPlanned
Downloading/Accessing data from this dataset implies acceptance of ECMWF's Terms of Use [https://apps.ecmwf.int/datasets/data/era40-daily/licence/]
None
NSF NCAR - Geoscience Data Exchange
National Center for Atmospheric Research
CISL/DECS
P.O. Box 3000
Boulder
80307
U.S.A.
(303)-497-1343
303-497-1291
pointOfContact
NSF NCAR Geoscience Data Exchange
NSF National Center for Atmospheric Research
CISL/DECS
P.O. Box 3000
Boulder
80307
U.S.A.
303-497-1291
name: NSF NCAR Geoscience Data Exchange
description: The NSF NCAR Geoscience Data Exchange - Integrated Research Data Commons (GDEX) contains an extensive collection of meteorological, atmospheric composition, and oceanographic observations and model outputs to support Earth System Science research. GDEX supports "data proximate" computational research through its integration with NSF NCAR High Performance Compute services [https://arc.ucar.edu/resources], which are made accessible to US researchers through a range of allocations opportunities [https://arc.ucar.edu/xras_submit/opportunities].
function: downlaod
pointOfContact
2025-10-03T00:01:43Z