Identification

Title

ERA40 T85 Monthly Mean Surface Analysis and Surface Forecast Fields, created at NCAR

Alternative title(s)

d126000

Abstract

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 surface and single level analysis variables were transformed from a reduced N80 Gaussian grid to a 256 by 128 regular Gaussian grid. 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 occurs in the sea surface temperature and sea ice 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 surface and single level 6-hour forecast variables were transformed from a reduced N80 Gaussian grid to a 256 by 128 regular Gaussian grid. 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. 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) [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/].

Resource type

dataset

Resource locator

https://rda.ucar.edu/datasets/d126000/

protocol: https

applicationProfile: browser

name: Dataset Description

description: Related Link

function: information

https://rda.ucar.edu/datasets/d126000/dataaccess/

protocol: https

applicationProfile: browser

name: Data Access

description: Related Link

function: download

Unique resource identifier

code

codeSpace

Dataset language

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

climatologyMeteorologyAtmosphere

Keywords

Keyword set

keyword value

dataset

originating controlled vocabulary

title

Resource Type

reference date

date type

revision

effective date

2014-10-16

Keyword set

keyword value

ERA40DAS > ERA40 Data Assimilation System

MODELS > MODELS

originating controlled vocabulary

title

U.S. National Aeronautics and Space Administration Global Change Master Directory

reference date

date type

revision

effective date

2024-07-23

Keyword set

keyword value

ERA40 > ECMWF ERA40 Reanalysis Project

originating controlled vocabulary

title

U.S. National Aeronautics and Space Administration Global Change Master Directory

reference date

date type

revision

effective date

2024-07-24

Keyword set

keyword value

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC RADIATION > OUTGOING LONGWAVE RADIATION

EARTH SCIENCE > LAND SURFACE > SOILS > SOIL TEMPERATURE

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC PRESSURE > SEA LEVEL PRESSURE

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WINDS > SURFACE WINDS

EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SNOW/ICE > SNOW/ICE TEMPERATURE

EARTH SCIENCE > LAND SURFACE > SURFACE RADIATIVE PROPERTIES > ALBEDO

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WATER VAPOR > WATER VAPOR INDICATORS > WATER VAPOR

EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > SURFACE ROUGHNESS

EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SNOW/ICE > ALBEDO

EARTH SCIENCE > LAND SURFACE > SURFACE THERMAL PROPERTIES > SKIN TEMPERATURE

EARTH SCIENCE > ATMOSPHERE > AIR QUALITY > TROPOSPHERIC OZONE

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC RADIATION > HEAT FLUX

EARTH SCIENCE > BIOSPHERE > VEGETATION > VEGETATION COVER

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC RADIATION > LONGWAVE RADIATION

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC RADIATION > INCOMING SOLAR RADIATION

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WATER VAPOR > WATER VAPOR INDICATORS > DEW POINT TEMPERATURE

EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION

EARTH SCIENCE > ATMOSPHERE > ALTITUDE > PLANETARY BOUNDARY LAYER HEIGHT

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC PRESSURE > GRAVITY WAVE

EARTH SCIENCE > OCEANS > SEA ICE > ICE EXTENT

EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SNOW/ICE > SNOW DEPTH

EARTH SCIENCE > CRYOSPHERE > SNOW/ICE > SNOW/ICE TEMPERATURE

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC RADIATION > SHORTWAVE RADIATION

EARTH SCIENCE > ATMOSPHERE > CLOUDS > CLOUD PROPERTIES > CLOUD FREQUENCY

EARTH SCIENCE > ATMOSPHERE > PRECIPITATION > SOLID PRECIPITATION > SNOW

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WATER VAPOR > WATER VAPOR PROCESSES > EVAPORATION

EARTH SCIENCE > LAND SURFACE > SOILS > SOIL MOISTURE/WATER CONTENT

EARTH SCIENCE > OCEANS > OCEAN TEMPERATURE > SEA SURFACE TEMPERATURE

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WATER VAPOR > WATER VAPOR INDICATORS > TOTAL PRECIPITABLE WATER

EARTH SCIENCE > ATMOSPHERE > PRECIPITATION > PRECIPITATION AMOUNT

EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SNOW/ICE > SNOW MELT

EARTH SCIENCE > BIOSPHERE > VEGETATION > VEGETATION SPECIES

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WINDS > WIND DYNAMICS > WIND STRESS

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC TEMPERATURE > SURFACE TEMPERATURE > AIR TEMPERATURE

EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SURFACE WATER > SURFACE WATER PROCESSES/MEASUREMENTS > RUNOFF

EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SNOW/ICE > SNOW DENSITY

originating controlled vocabulary

title

U.S. National Aeronautics and Space Administration Global Change Master Directory

reference date

date type

revision

effective date

2024-07-24

Geographic location

West bounding longitude

-180

East bounding longitude

180

North bounding latitude

88.928

South bounding latitude

-88.928

Temporal reference

Temporal extent

Begin position

1957-09-01T00:00:00Z

End position

2002-08-31T18:00:00Z

Dataset reference date

date type

publication

effective date

2005-05-09

Frequency of update

notPlanned

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Downloading/Accessing data from this dataset implies acceptance of ECMWF's Terms of Use [https://apps.ecmwf.int/datasets/data/era40-daily/licence/]

Limitations on public access

None

Responsible organisations

Responsible party

organisation name

UCAR/NCAR - Research Data Archive

full postal address

National Center for Atmospheric Research

CISL/DECS

P.O. Box 3000

Boulder

80307

U.S.A.

telephone number

(303)-497-1343

facsimile number

303-497-1291

email address

davestep@ucar.edu

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact

organisation name

NCAR Research Data Archive

full postal address

National Center for Atmospheric Research

CISL/DECS

P.O. Box 3000

Boulder

80307

U.S.A.

facsimile number

303-497-1291

email address

rdahelp@ucar.edu

web address

https://rda.ucar.edu/

name: NCAR Research Data Archive

description: The Research Data Archive (RDA), managed by the Data Engineering and Curation Section (DECS) of the Computational and Information Systems Laboratory (CISL) at NCAR, contains a large and diverse collection of meteorological and oceanographic observations, operational and reanalysis model outputs, and remote sensing datasets to support atmospheric and geosciences research, along with ancillary datasets, such as topography/bathymetry, vegetation, and land use.

function: downlaod

responsible party role

pointOfContact

Metadata date

2024-08-04T02:10:30Z

Metadata language

eng; USA