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This part includes a brief description and the order forms
of this specific Data Set. Description
:The Supplementary Fields are derived from short term forecasts used
as "first-guess" for analyses within ECMWF's data assimilation system.
Data are archived at the resolution of the operational system in use at ECMWF.
Since the resolution and internal representation of the archive may vary according
to changes in ECMWF's operational practice, data services associated with this
data set include the provision of interpolation to requested resolutions and representation
forms. The Supplementary Fields Data Set is defined as: - period
supported - 1January 1985 to current date;
- fields are 6-hour forecast
values valid for 0000 UTC, 0006 UTC, 1200 UTC and 1800 UTC each day until 11 September
2000, from 12 September 2000 the archive is based on 6 and 12 hour forecasts from
0000 and 1200 UTC each day;
- each parameter is stored as a field of grid
point values, in latitude rows starting at the north and working southwards; within
each row values run from west to east starting at the 0° meridian;
- data
are stored in FM 92 GRIB using sufficient bits to ensure that the grid point values
can be retrieved to an accuracy consistent with the generating methods used;
The
changes to the archive are as follows:
| 1
January 1985 | Internal data representation
is in a N48 Gaussian grid
(48 lines of latitude between the pole and the equator for each hemisphere, with
a regular spacing of 1.875° between points along each latitude row) fields
available are total cloud cover, boundary layer dissipation, surface sensible
heat flux, surface latent heat flux, surface thermal radiation, surface solar
radiation, top thermal radiation, top solar radiation, East-West surface stress,
North-South surface stress, evaporation |
| 1 May 1985 | Internal data
representation is in a
N80 Gaussian grid (80 lines of latitude between the pole and the equator
for each hemisphere, with a regular spacing of 1.125° between points along
each latitude row) | | 15
July 1986 | fields added are latitudinal component of gravity
wave stress, meridional component of gravity wave stress, gravity wave dissipation
| | 17
September 1991 | Internal data representation is in
an N160 Quasi-regular
Gaussian grid (160 lines between the pole ands the equator, with varying numbers
of points along each row) |
| 14 May 1997 | fields added
are surface thermal radiation downward, surface solar radiation downward |
| 12
September 2000 | archive changed from four 6 hour forecasts
per day to two 12 hour forecasts with steps 6 and 12 available |
| 21 November 2000 | Internal
data representation is in an
N256 Quasi-regular Gaussian grid (256 lines between the pole and the equator,
with varying numbers of points along each row) | Order forms :If you wish to make an order
from this data set please download the following two Acrobat (PDF) files :
| 1. Instructions and Standard Order forms (common
for all data sets): |
24 KB | | | | 2. Data
Set Order form (to select data from this specific data set only) : |
8 KB
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