Every day, ECMWF produces various global Analyses and Forecasts and archives them in MARS. The first ECMWF numerical model in 1979 was a grid-point model with 15 levels in the vertical and a horizontal resolution of 1.875 degrees in latitude and longitude, corresponding to a grid length of 200 kilometres. A number of major changes have occurred since ECMWF's activity started:

IFS Cycle 48r1, implemented on 27 June 2023, increased the horizontal resolution of the medium-range ensemble (ENS) from 18 to 9 km and introduced a major upgrade to the configuration of the extended-range ensemble (ENS extended): Rather than being an extension of the medium-range forecasts starting twice a week at day 15 it will be a completely separate system, running daily from 00 UTC out to day 46 with 101 members. Over the entire forecast range the resolution will remain unchanged at 36 km horizontally and 137 model levels. As a result of these configuration changes Cycle 48r1 will offer two sets of re-forecasts (=hindcasts), one for the medium range and one for the extended range.
The upgrade to IFS Cycle 47r2 on 11 May 2021 increased the vertical resolution for the ensemble (ENS, streams enfo, enfh, efov, efho) from 91 to 137 model levels, bringing it in-line with the HRES resolution.
5 Nov 2017: Implementation of Seasonal Forecast SEAS5
With the upgrade on 22 November 2016, the medium-range ensemble and its monthly extension see a major upgrade in the dynamical ocean model (NEMO): the resolution is increased from 1° and 42 layers to 0.25° and 75 layers (ORCA025Z75). Furthermore, NEMO model version v3.4.1 with the interactive sea-ice model (LIM2) is implemented. The ocean and sea-ice components of the ENS initial conditions are provided by the new ocean analysis and reanalysis suite ORAS5, which uses the new ocean model and revised ensemble perturbation method.
On 8 March 2016 with the introduction of cycle 41r2 the horizontal resolution was upgraded, equivalent to about 9 km for HRES and the data assimilation (the outer loop of the 4D-Var) and to about 18 km for the ENS up to day 15. The resolution of the ENS extended (day 16 up to day 46) is about 36 km. Cycle 41r2 also introduced a new reduced Gaussian grid, the octahedral grid. > Full description

In Apr 2015 with cycle 41r1 the domain of the limited-area ocean wave model has been extended to the full globe and is now referred to as HRES-SAW. The ENS configuration has been changed and new climate files have been introduced. > Full description
In June 2013 IFS cycle 38r2 introduced higher vertical resolution in the high-resolution (T1279) forecast and data assimilation of the operational runs at 00 and 12 UTC (HRES) as well as the 06 and 18 UTC cycles of the Boundary Conditions (BC) optional programme. The number of model levels increases from the current 91 levels (L91) to 137 levels (L137).In January 2010 the horizontal resolution of the deterministic model has been increased to T1279. The resolution of the EPS went up to T639/T319 for Leg A/B, respectively.
In March 2008 VarEPS and monthly forecasting were combined into a single system. On Thursday of each week, the 00 UTC VarEPS forecast are extended from 15 to 32 days at a resolution of T255 L62 with ocean coupling introduced from day 10.
In March 2007 the operational seasonal forecasting system has been upgraded from System 2 to System 3 and integrated in the Multi-Model Seasonal Forecast stream. The resolution of the atmospheric model has been increased to T159L62.
In November 2006 the EPS has been upgraded to Variable Resolution Ensemble Prediction System (VarEPS). In particular, the forecast range was extended to 15 days using the VarEPS system with a resolution of T399 L62 for day 1 to day 10 and T255 L62 for day 11 to day 15.
In February 2006 the resolution of the deterministic model has been increased to T799 and 91 model levels. The resolution of the Ensemble Prediction System (EPS) went up to T399 and 62 model levels.
In June 2004, the Early Delivery Forecasting System was implemented, comprising two main 6-hour 4d-Var analysis and forecast cycles for 00 and 12 UTC and two additional 12-hour 4d-Var analysis and first guess forecast cycles.
In November 2000, the spectral truncation was extended to wave number 511.
In September 2000, 4d-Var cycling was increased to 12 hours. Type First Guess has been discontinued.
In October 1999, the number of levels was increased to 60.
In October 1999, the number of levels was increased to 60.
In March 1999, the number of levels was increased to 50.
In June 1998, the atmospheric model and the wave model were coupled in order to take advantage of the boundary conditions they represent to each other.
In April 1998, the spectral truncation was extended to wave-number 319.
In November 1997, 4d-Var (four-dimensional variational Analysis) became operational.
In 1992, a wave model used for ocean wave forecasting (the WAM model) became operational, followed after a few months by a Mediterranean implementation.
In December the Ensemble Prediction System (EPS) with 32 members and a resolution of T63L31 became operational.
In September 1991, a much higher resolution spectral model was put into operation. The spectral truncation was extended to wave-number 213 and the number of levels was increased to 31 (i.e. T213L31).
In May 1985, the spectral truncation was extended to wave-number 106. The number of levels was increased to 19 in 1986.
In April 1983, the grid-point model was replaced by a T63 spectral model (i.e. a spectral representation in the horizontal with a triangular truncation at wave-number 63). The number of levels in the vertical was increased to 16.

In addition, various other projects run on a regular basis, such as Seasonal Forecast, Multi-Analysis Ensemble, Monthly Forecast and Sensitivity forecast, or have run in the past, for example the ECMWF reanalyses. All their outputs are available in MARS. The majority of Observations used as model input are also available in MARS.

A comprehensive list of changes in the ECMWF model can be found on our main website, giving detailed documentation on significant changes to the operational forecasting system.

Products

In order to know the data available from MARS, users need to be familiar with ECMWF's activities. The overview given below is not exhaustive. It is rather meant as an introduction to ECMWF's activities and the most common products. Users wanting to learn more are encouraged to study the Forecast User Guide.

The datasets pages on the main website provide a good entry point to browse the MARS content in particular for operational and reanalysis data. From there you will also find links into the MARS Catalogue, which allows you to browse the entire MARS content.

Operational data produced daily at ECMWF

Atmospheric models

Analysis:global analyses for the four main synoptic hours 00, 06, 12 and 18 UTC. They are the best gridded estimate of the state of the atmosphere (best fit to observations). For each of the synoptic hours, data is produced at the following levels:
- Surface fields represent the meteorology at the surface.
- Model levels are used in ECMWF's forecast model to resolve the atmosphere in the vertical.
- Pressure levels are interpolated by the model from its Model Levels.
- Isentropic levels are either potential vorticity or potential temperature.
Forecast:global 10-day forecasts based on the 00/12 UTC Analysis (the 00 UTC run started on March 2001 as an experimental suite for severe weather prediction). Forecast products are classified in the same level types as Analysis data: Surface, Model levels, Pressure levels, and Isentropic levels. Meteorological parameters are written output for every forecast time step, 3-hourly intervals from 00 to 72 hours, and 6-hourly from 72 to 240 hours.
First guess:a forecast with base time from the previous synoptic hour and a forecast time step of (usually) 6 hours. Note that since the change to 12 hour-cycling 4d-Var in the year 2000, this type of data has been discontinued.
Initialised Analysis:the best 'balanced' gridded estimate of the state of the atmosphere (initial state of the forecast). With the implementation of the three dimensional variational Analysis (3d-Var) on January 1996, the Initialised Analysis is no longer produced, and the Analysis is the best and the best 'balanced' gridded estimate of the atmosphere.
Four-dimensional variational Analysis:analyses using observations over a time window (e.g. a 6 hour 4d-Var at cycle hh will contain observations from hh-02:59 to hh+03:00).
Errors in Analysis:the assumed uncertainty of an observation is combined with the assumed uncertainty of the First Guess, resulting in an estimate of the total uncertainty in the Analysis
Errors in First Guess:result of the uncertainty of the First Guess compared with observations
Four-dimensional variational Analysis increments:the low resolution increment which is added to the first-guess after each inner loop minimisation.

Ocean wave models

Since 1998, ECMWF's atmospheric model is coupled with a wave model.

HRES-WAM (High RESolution WAve Model) is coupled to the atmospheric model (HRES) while HRES-SAW (High RESolution Stand Alone Wave model) is run as a standalone model. HRES-SAW, formerly known as LAM WAM (Limited Area Model WAM), Mediterranean or European Wave Model, now covers the whole globe (see Cycle 41r1 upgrade).

HRES-WAM and HRES-SAW offer the same parameters globally. > more details

Ensemble Prediction System

ECMWF's Ensemble Prediction System has a coupled atmospheric and wave model. On 28 November 2006 the Variable Resolution Ensemble Prediction System (VarEPS) has been introduced by extending the forecast range from 10 to 15 days with a resolution of T399L62 for day 1 to day 10 (Leg 1) and T255L62 for day 11 to day 15 (Leg 2). On 11 March 2008 the Monthly Forecasting System, running once a week, has been integrated with the VarEPS. The new monthly forecast products were produced for the first time on 13 March 2008. With Cycle 48r1, 12 May 2015, Leg 2 was extended to 46 days (instead of 32) on Mondays and Thursday (at 00UTC) and the number of re-forecasts increased to 11 members twice per week. On 8 March 2016, Cycle 41r2, the upgraded horizontal resolution increased to about 18 km up to day 15 and about 36 km for the extended range. The resolution of the ensemble of data assimilations (EDA) is increased to 18 km. With Cycle 43r1, 22 November 2016, the resolutions of the dynamical ocean model (NEMO) increased from 1 degree and 42 layers to 0.25 degrees and 75 layers. The upgrade to IFS Cycle 47r2 on 11 May 2021 increased the vertical resolution for the ensemble (ENS, streams enfo, enfh, efov, efho) from 91 to 137 model levels.
IFS Cycle 48r1, implemented on 27 June 2023, increased the horizontal resolution of the medium-range ensemble (ENS) from 18 to 9 km and introduced a major upgrade to the configuration of the extended-range ensemble (ENS extended): Rather than being an extension of the medium-range forecasts starting twice a week at day 15 it will be a completely separate system, running daily from 00 UTC out to day 46 with 101 members. Over the entire forecast range the resolution will remain unchanged at 36 km horizontally and 137 model levels. As a result of these configuration changes Cycle 48r1 will offer two sets of re-forecasts (=hindcasts), one for the medium range and one for the extended range.

Control forecast: an unperturbed forecast at a lower resolution than the main HRES 10-day forecast. Forecast runs to 15 days, with lower resolution from truncation step 240 onwards. Data is available on Surface, Model levels, Pressure levels and Isentropic levels.
Calibration/Validation forecast: VarEPS includes two constant-resolution forecasts for calibration and validation purposes which run for both resolutions from day 1 - 15. Data is available on Surface, Model levels, Pressure levels and Isentropic levels.
Perturbed forecasts: different forecasts to 10 days with perturbed initial conditions. They are numbered from 1 to N depending on the EPS setup. Data is available on the Surface and on Pressure levels and Isentropic levels.
Initial condition perturbations: the initial conditions for the EPS are designed to represent the uncertainties inherent in the operational analysis. They are created by adding perturbations to the operational analysis which produce the fastest energy growth during the first two days of the forecast period, defined using the singular vector technique.
Forecast probabilities: a statistical distribution of the weather parameters from all ensemble members is used to produce probabilistic weather forecasts. With the introduction of VarEPS this data type has been discontinued.
Event probabilities: provide the probabilities of the occurrence of weather events at each grid point. The probabilities are calculated on the basis that each ensemble member is equally likely.
Ensemble means: are means of the ensemble forecast members.
Clusters: similar ensemble members are grouped together into clusters. The mean and standard deviation of these clusters are computed (as well as the mean and standard deviation of the overall ensemble). Five sets of clusters are computed, one for the entire European area, and four for smaller areas.
Tubes: another clustering method which averages all ensemble members which are close to the ensemble mean and excludes members which are significantly different.
Extreme Forecast Index (EFI): measures the difference between the probability distribution from the EPS and the model climate distribution.

Boundary conditions

The Boundary Condition Optional Programme (BC) was initially set up in June 2000, to provide participating Member States with boundary conditions for their limited area models: four additional 3D-Var Analysis runs for 00, 06, 12 and 18 UTC with a cut-off time of 4 hours, followed by global 4-day forecasts. All analysis data but only the forecast from 00 UTC are archived.

Since 14 Mar 2006 the BC production has been merged with the main operational forecast suite. In the new configuration, only the 06 and 18 UTC runs are part of the BC suite. For 00 and 12 UTC analysis and forecast are provided by the main operational HRES runs. Now all four data assimilation cycles are based on 6h 4d-Var with a cut-off time of 4 hours.

Since 15 Nov 2011 hourly output is produced from all 4 forecast runs.

The BC analysis and forecast fields, also referred to as short cut-off, are stored temporarily in MARS as STREAM=SCDA. The hourly data for 00 and 12 UTC are archived together with the main forecast runs as STREAM=DA.

On 22 June 2015 additional ensemble forecasts at 06/18 UTC have been added to the archive. The data can be retrieved using stream ENFO and WAEF.

There is currently only limited temporal storage in MARS for these products in line with the archive data available for 00 and 12 UTC, and no model levels are archived for the perturbed forecasts. Model level data can only be retrieved from MARS while the data is still available in the FDB, which is usually for up to two days for all four ENS cycles. Since July 2018 the full BC ENS data is available online in a rolling archive covering 30 days, see ENS BC model level data in MARS.

Valid BC data are available to members of the BC programme. They are also available to NMHSs of WMO, international organisations and research projects according to the rules laid out in the "Rules governing the distribution and dissemination of ECMWF real-time products".

Since 1 October 2018 the hourly data from 00/06/12/18Z forecast runs produced in the Boundary Conditions Programme are part of the Catalogue of ECMWF real-time products as " High Frequency Products".

Multi-Analysis Ensemble

Every day ECMWF receives Analyses from four centres, NCEP, The Met Office, Météo-France and Deutscher Wetterdienst, and runs 5 forecasts, 1 based on each different analyses plus one compound of all the analyses (consensus) including ECMWF's Analysis.

Seasonal Forecast

ECMWF started an experimental programme for seasonal prediction in 1995, which attempts to predict seasonal changes by coupling three models: atmospheric, wave and ocean models. > More information on the Seasonal Forecast

Monthly Forecast

The monthly forecast (extended-range) is an extension of the ensemble (ENS) twice a week, on Monday and Thursday, to 46 days. > More information on the Monthly Forecast

Monthly Forecast (7 Oct. 2004 - 11 March 2008)

This section describes the archiving of the monthly forecasting system after it became operational (7 October 2004 ) and before it was merged into the Ensemble Prediction System (11 March 2008).

Monthly archive of atmospheric fields:

Raw data:

The IFS writes the real-time data into the MNFC (1200) stream in MARS and the hindcast into the MNFH (1201) stream in MARS. All the data are archived using their original model representation (Reduced Gaussian grid or Spherical Harmonics). Upper-air fields are archived every 12 hours, whereas surface fields are archived every 6, 12 or 24 hours.

Upper-air fields (archived every 12 hours):

129	Geopotential	1000	925	850	700	500	-	-	200	100	50	10	(also MEAN of each level)
130	Temperature	1000	925	850	700	500	400	300	200	100	50	10	(also MEAN of each level)
138	Vorticity (relative)	1000	925	850	700	500	-	-	200	100	50	10	(also MEAN of each level)
155	Divergence	1000	925	850	700	500	-	-	200	100	50	10	(also MEAN of each level)
133	Specific humidity (gridpoint)	1000	925	850	700	500	-	-	200	100	50	10	(also MEAN of each level)
001	Stream function	-	-	-	-	-	-	-	200	-	-	-	(also MEAN of each level)
002	Velocity potential	-	-	-	-	-	-	-	200	-	-	-	(also MEAN of each level)

60

Potential vorticity on the 330K isentropic surface

MEAN

03

Potential temperature on the 2E-6 potential vorticity surface

MEAN

Surface fields:

The following surface fields are archived every 6 hours (16 fields):

31	Sea-ice cover (since June 2005)	MEAN/MAX/MIN/SD
39	Volumetric soil water layer 1	MEAN/MAX/MIN/SD
49	Wind gust at 10m	MEAN/MAX/MIN/SD
139	Soil temp level 1	MEAN/MAX/MIN/SD
142	Large scale precipitation	MEAN/MAX/MIN/SD
143	Convective precipitation	MEAN/MAX/MIN/SD
144	Snow fall	MEAN/MAX/MIN/SD
151	Mean sea level pressure	MEAN/MAX/MIN/SD
159	Boundary layer height	MEAN/MAX/MIN/SD
164	Total cloud cover	MEAN/MAX/MIN/SD
165	10 metre u wind component	MEAN/MAX/MIN/SD
166	10 metre v wind component	MEAN/MAX/MIN/SD
167	2 metre temperature	MEAN/MAX/MIN/SD
168	2 metre dewpoint temperature	MEAN/MAX/MIN/SD
189	Sunshine duration	MEAN/MAX/MIN/SD
201	Max 2m temperature since last postprocessing	MEAN/MAX/MIN/SD
202	Min 2m temperature since last postprocessing	MEAN/MAX/MIN/SD
228	Total precipitation	MEAN/MAX/MIN/SD

The following surface fields are archived every 24 hours (16 fields):

40	Volumetric soil water layer 2	MEAN/MAX/MIN/SD
41	Volumetric soil water layer 3	MEAN/MAX/MIN/SD
42	Volumetric soil water layer 4	MEAN/MAX/MIN/SD
141	Snow depth	MEAN/MAX/MIN/SD
146	Surface sensible heat flux	MEAN/MAX/MIN/SD
147	Surface latent heat flux	MEAN/MAX/MIN/SD
169	Surface solar radiation downwards	MEAN/MAX/MIN/SD
170	Soil temp level 2	MEAN/MAX/MIN/SD)
175	Surface thermal radiation downwards	MEAN/MAX/MIN/SD
176	Surface solar radiation	MEAN/MAX/MIN/SD
177	Surface thermal radiation	MEAN/MAX/MIN/SD
178	Top solar radiation	MEAN/MAX/MIN/SD
179	Top thermal radiation	MEAN/MAX/MIN/SD
180	East/West surface stress	MEAN/MAX/MIN/SD
181	North/South surface stress	MEAN/MAX/MIN/SD
182	Evaporation	MEAN/MAX/MIN/SD

The following field is archive only at step=0 and 24 and for the control forecast (type=cf):

172

Land/sea mask

The following derived fields are not archived directly, but their weekly statistics are calculated:

207

10m scalar wind speed

MEAN/MAX/MIN/SD

Monthly archive of ocean fields:

Ocean data is output in different sections, H = horizontal, Z = zonal, M = meridional. There are also sections that include the time dimension: Z=longitude-time, M=latitude-time and V=depth-time. Each of these sections is a two-dimensional field, with a particular orientation in space and time. Each forecast ensemble member archives the output listed below. The ocean data is archived together with the atmosphere data, and is distinguished by the 'LEVTYPE' attribute, which is set to 'DEPTH' or 'DP'.

The following instantaneous fields are written every 24 hours. They should allow a rough estimate of drift in the ocean, and give a snapshot of any numerical problems.

Horizontal fields are:

Section	Code	Depth	Name
H	129	5/425	Potential temperature
H	130	5/425	Salinity
H	131	5	u-velocity
H	132	5	v-velocity
H	145	0	Sea-level
H	148	0	Mixed-layer depth
H	133	225	w-velocity

Vertical zonal sections are:

Section	Code	Latitude	Name
Z	129	0	Potential temperature
Z	130	0	Salinity
Z	131	0	u-velocity
Z	132	0	v-velocity
Z	133	0	w-velocity

Vertical meridional sections are:

Section	Code	Longitude	Name
M	129	220	Potential temperature
M	130	220	Salinity
M	131	220	u-velocity
M	132	220	v-velocity
M	133	220	w-velocity

The following accumulated fields are written once per month during the forecasts. Monthly means can be derived from them. They are the main fields for diagnosing the oceanic behaviour of the coupled model forecasts.

Accumulated horizontal fields are:

Section	Code	Depth	Name
H	129	5	Potential temperature
H	130	5	Salinity
H	131	5	u-velocity
H	132	5	v-velocity
H	145	0	Sea level
H	148	0	Mixed layer depth
H	163	0	Depth of 20 deg isotherm
H	164	0	T averaged over upper 300m
H	175	0	S averaged over upper 300m
H	153	0	Zonal wind stress
H	154	0	Meridional wind stress
H	156	0	Net surface heat flux
H	157	0	Absorbed solar radiation
H	158	0	Precipitation - Evaporation

Accumulated vertical zonal sections are:

Section	Code	Latitude	Name
Z	129	0	Potential temperature
Z	130	0	Salinity
Z	131	0	u-velocity
Z	133	0	w-velocity

Accumulated vertical meridional sections are:

Section	Code	Longitude	Name
M	129	60E/90E/165E/180/140W/95W/30W/10W	Potential temperature
M	130	60E/90E/165E/180/140W/95W/30W/10W	Salinity
M	131	60E/165E/140W/30W	u-velocity
M	132	60E/165E/140W/30W	v-velocity
M	133	60E/165E/140W/30W	w-velocity
M	138	60E/165E/140W/30W	Potential density

Several so-called time series fields are also produced. These allow detailed examination of the evolution of certain fields along given lines of latitude or longitude. In all cases the temporal resolution is daily.

Lines of latitude are:

Section	Code	Depth	Latitude	Name
Z	129	5	0	Potential temperature
Z	131	5	0	U velocity
Z	145	0	0	Sea level
Z	163	0	0	Depth of 20 deg isotherm
Z	153	0	0	Zonal wind stress
Z	164	0	8N/5N/0/5S/8S	T averaged over upper 300m

Lines of longitude are:

Section	Code	Depth	Longitude	Name
M	129	5	180/60W	Potential temperature
M	145	0	180/60W	Sea level
M	148	0	180/60W	Mixed layer depth

Finally, a small selection of instantaneous fields is output daily, to allow study of the evolution of the system on synoptic timescales. The fields concerned are:

Section	Code	Depth	Name
H	129	5	Potential temperature
H	145	0	Sea level
H	148	0	Mixed layer depth
M	129	0	Potential temperature

Probabilities (since 30 June 2005):

Anomaly events:

Parameter name	Acronym	Grib code	Table 2 version
2m temperature warm anomaly of at least 2K	2TWA2K	1	131
2m temperature warm anomaly of at least 1K	2TWA1K	2	131
2m temperature warm anomaly of at least 0K	2TWA0K	3	131
2m temperature cold anomaly of at least 1K	2TCA1K	4	131
2m temperature cold anomaly of at least 2K	2TCA2K	5	131
Total precipitation anomaly of at least 20 mm/week	TPAGT20	6	131
Total precipitation anomaly of at least 10 mm/week	TPAGT10	7	131

Probability distribution :

Quantile		Distribution	Number	Total number	Mars request
quintile	1st	0 to 20%	1	5	1:5
	2nd	20 to 40%	2	5	2:5
	3rd	40 to 60%	3	5	3:5
	4th	60 to 80%	4	5	4:5
	5th	80 to 100%	5	5	5:5
tercile	1st	0 to 33.333%	1	3	1:3
	2nd	33.333 to 66.666%	2	3	2:3
	3rd	66.666 to 100%	3	3	3:3
decile	1st	0 to 10%	1	10	1:10
	10th	90 to 100%	10	10	10:10

Probabilty boundary:

Quantile		Distribution	Number	Total number	Mars request
quintile	1st	20%	1	5	1:5
	2nd	40%	2	5	2:5
	3rd	60%	3	5	3:5
	4th	80%	4	5	4:5
tercile	1st	33.333%	1	3	1:3
	2nd	66.666%	2	3	2:3
decile	1st	10%	1	10	1:10
	10th	90%	9	10	9:10

13.02.2008eam MNFW (1203) for the
real-time forecast and in the stream MFHW (1204) for the hindcast.

In order to retrieve these fields from MARS, three MARS command lines have to be added: method=1, system=2, and origin=ecmf but may change, if the monthly forecasting system is modified. Look at the System Change Notice to see which system value is valid. For the control forecast TYPE=CF, for perturbed forecasts TYPE=FC. For the hindcast, the reference date of the hindcast (date of the real-time forecast associated to the hindcast) has to be present in the MARS request: REFDATE=YYYYMMDD,

Example of MARS request:

retrieve,
class="od",expver=0001,stream=mnfc,type=fc,method=1,system=2,levtype=pl,origin=ecmf, level=500,param=Z,number=1/to/50,date=20041007,time=00,step=0/to/768/by/12, target="out"

for the back statistics:

retrieve,
class="OD",expver=0001,stream=mnfh,type=fc,method=1,system=2,levtype=PL,origin=ecmf, level=500,param=Z,number=1/to/4,date=19921007,refdate=20041007,time=00, step=12/to/768/by/12,target="out"

Weekly Means:

Monthly forecast weekly means are calculated for all atmospheric variables and stored in the stream MNFM (1206) for the real-time forecast and stream MFHM (1207) for he hindcast with type FCMEAN.

Wave model forecast means (weekly means) are calculated and stored in the stream MFWM(1209) for the real-time forecast and stream MHWM(1210) for the hindcast.

Monthly forecast weekly maximum (type FCMAX), minimum (type FCMIN) and standard deviation (type FCSTDEV) have also been calculated and archived for all surface fields.

The weeks are as follow:

Week1: day 5 to day 11 (FCPERIOD=05-11)
Week2: day 12 to day 18 (FCPERIOD=12-18)
Week3: day 19 to day 25 (FCPERIOD=19-25)
Week4: day 26 to day 32 (FCPERIOD=26-32)

Since the monthly forecast starts every Thursday at 00Z, they correspond to the week from Monday at 0Z to Sunday at midnight.

Here is an example of MARS retrieval for weekly means from the real-time forecast:

retrieve,
class="OD",expver=0001,stream=mnfm,type=fcmean,method=1,system=2,levtype=PL,
level=500,param=Z,number=1/to/50,date=20041007,time=00,fcperiod=05-11,
origin=ecmf,target="out"

and from the hindcast:

retrieve,
class="OD",expver=0001,stream=mfhm,type=fcmean,method=1,system=2,levtype=PL,
level=500,param=Z,number=1/to/4,date=19921007,refdate=20041007,time=00, fcperiod=05-11, origin=ecmf,target="out"

Ensemble means and standard deviation

Ensemble means and standard deviations are archived in MARS only for a limited
number of fields: temperature at 850 and 500 hPa and geopotential at 1000 and
500 hPa.

To retrieve these fields, TYPE=EM (ensemble mean) or TYPE=ES
(ensemble standard deviation).

Example with the real-time forecast:

retrieve, class="OD",expver=0001,stream=mnfc,type=em,method=1,system=2,levtype=PL, level=500,param=Z, date=20041007,time=00,step=24,origin=ecmf,target="out"

for the hindcast:

retrieve, class="OD",expver=0001,stream=mnfh,type=em,method=1,system=2,levtype=PL, level=500,param=Z,date=off, refdate=20041007,time=00,step=24,origin=ecmf,target="out"

It is important to note, that for the hindcast there is no date associated to the MARS request, just a reference date (REFDATE). For the hindcast, the ensemble mean represents the mean over the 5-member ensemble for each year of the hindcast set associated to the reference date. Since the hindcast covers 12 years, this represents the ensemble mean (or standard deviation) over 60 members.

Weekly anomalies

The anomalies are the difference between the real-time forecast and the model climatology. The model climatology corresponds to the ensemble mean of the hindcast.

Monthly forecast weekly anomalies are written into the MFAM (1208) stream in MARS. The MARS request is the same has for the raw data of the real-time forecast, with stream=MFAM instead of stream=MNFM. Wave model weekly anomalies are written into the stream MAWM (1211).

EPSgrams

In order to avoid retrieving 51 members for the real-time forecast or 60 members for the back statistics to create EPSgrams, several fields have been reordered, and the minimum, 25%, median, 75% and maximum of the ensemble distribution have been archived. These fields are: T850, total cloud cover, 2-metre temperature, total precipitation and 10 metre scalar wind speed.

To retrieve these fields: STREAM=MNFC, TYPE=ED, NUMBER=0 (minimum), NUMBER=12
(25%), NUMBER=25 (MEDIAN), NUMBER=37 (75%) or NUMBER=50 (MAXIMUM)

example:

retrieve,class=OD,expver=0001,stream=mnfc,type=ed,method=1,system=2,number=25,levtype=PL, level=850,param=T,date=20041007,time=00,step=24,origin=ecmf,target="out"

As for types em and es, there is no date in the MARS retrieval command for the hindcast. The reordering is made over the 60 members of the 12-year hindcast. The reference date is used in the MARS retrieval command.

Forecast probabilities:

There are 2 types of forecast probabilities: anomaly events (probability for a certain variable to exceed a threshold) and probability distributions (quantiles). At present, they are available only for weekly mean anomalies.

1) Anomaly event:

Example: Probability that the weekly averaged 2m temperature anomaly exceeds 2K

Each anomaly event has a specific parameter code in table 131. For instance, the probability that the weekly averaged 2m temperature anomaly exceeds 2K has the parameter code 1 in table 131, which corresponds to the acronym 2TWA2K. The anomaly events are archived as type fp.

example:

retrieve, stream=mfam, origin=ecmf, system=2, method=1, time=00, levtype=sfc, expver=1,
param=2TWA2K, class="od", date=20050630, fcperiod=12-18/19-25/26-32/5-11, type=fp, target="out"

2) Probability distribution:

Probability distribution is the probability to be in a given quantile. The quantiles are defined from the model climatology.

A new keyword has been defined: quantile. The syntax is quantile=X:Y, which means quantile X out of Y.

For example, quantile=1:3 means the probability distribution in the first tercile (lower tercile).

Example:

retrieve,stream=mfam,origin=ecmf,system=2,method=1,time=00,levtype=sfc,expver=1,param=167,
quantile=1:3,class=od,date=20050630,fcperiod=12-18/19-25/26-32/5-11,type=pd,target="out"

3) Probability boundaries:

Probability boundaries are the threshold values which define the quantiles. They are computed from the model climatologyy.

The syntax is the same as for probability distributions, except type=pb instead of type=pd.

For example, type=pb, quantile=1:3 means the boundary distribution between the lower and middle tercile.

Example:

retrieve,stream=mfam,origin=ecmf,system=2,method=1,time=00,levtype=sfc,expver=1,param=167, quantile=1:3,class=od,date=20050630,fcperiod=12-18/19-25/26-32/5-11,type=pb,target="out"

Monthly archive of ocean fields:

The ocean data are archived together with the atmospheric data, and are distinguished by the 'LEVTYPE' attribute, which is set to 'DEPTH' or 'DP'. Ocean variables are archived as instantaneous fields (product=inst), accumulated fields (product=tacc) or time series (product=tims). The fields are archived along horizontal (section=h), meridional (section=m) or zonal sections (section=z).

Pre-operational Monthly Forecast (1990 - 2004)

This section describes the archiving of the monthly forecasting system before it became operational (7 October 2004).

Monthly archive of atmospheric fields:

Raw data

The IFS writes its data into the MOFC (1090) stream in MARS. All of the data are archived using their original model representation (Reduced Gaussian Grid or Spherical Harmonics). Upper-air fields are archived every 12 hours, whereas surface fields are archived every 3, 6, 12 or 24 hours.

Upper-air fields (archived every 12 hours):

129	Geopotential	1000	925	850	700	500	-	-	200	(also MEAN of each level)
130	Temperature	1000	925	850	700	500	400	300	200	(also MEAN of each level)
138	Vorticity (relative)	1000	925	850	700	500	-	-	200	(also MEAN of each level)
155	Divergence	1000	925	850	700	500	-	-	200	(also MEAN of each level)
133	Specific humidity (gridpoint)	1000	925	850	700	500	-	-	200	(also MEAN of each level)

60

Potential vorticity on the 330K isentropic surface

MEAN

03

Potential temperature on the 2E-6 potential vorticity surface

MEAN

Surface fields:

The following surface field is archived every 3 hours (1 field):

164

Total cloud cover

MEAN/MAX/MIN/SD

The following surface fields are archived every 6 hours (11fields):

39	Volumetric soil water layer 1	MEAN/MAX/MIN/SD
49	Wind gust at 10m	MEAN/MAX/MIN/SD
139	Soil temp level 1	MEAN/MAX/MIN/SD
142	Large scale precipitation	MEAN/MAX/MIN/SD
143	Convective precipitation	MEAN/MAX/MIN/SD
144	Snow fall	MEAN/MAX/MIN/SD
159	Boundary layer height	MEAN/MAX/MIN/SD
165	10 metre u wind component	MEAN/MAX/MIN/SD
166	10 metre v wind component	MEAN/MAX/MIN/SD
167	2 metre temperature	MEAN/MAX/MIN/SD
168	2 metre dewpoint temperature	MEAN/MAX/MIN/SD

The following surface field is archived every 12 hours (1 field):

151

Mean sea level pressure

MEAN/MAX/MIN/SD

The following surface fields are archived every 24 hours (19 fields):

40	Volumetric soil water layer 2	MEAN/MAX/MIN/SD
41	Volumetric soil water layer 3	MEAN/MAX/MIN/SD
42	Volumetric soil water layer 4	MEAN/MAX/MIN/SD
141	Snow depth	MEAN/MAX/MIN/SD
146	Surface sensible heat flux	MEAN/MAX/MIN/SD
147	Surface latent heat flux	MEAN/MAX/MIN/SD
169	Surface solar radiation downwards	MEAN/MAX/MIN/SD
170	Soil temp level 2	MEAN/MAX/MIN/SD)
175	Surface thermal radiation downwards	MEAN/MAX/MIN/SD
176	Surface solar radiation	MEAN/MAX/MIN/SD
177	Surface thermal radiation	MEAN/MAX/MIN/SD
178	Top solar radiation	MEAN/MAX/MIN/SD
179	Top thermal radiation	MEAN/MAX/MIN/SD
180	East/West surface stress	MEAN/MAX/MIN/SD
181	North/South surface stress	MEAN/MAX/MIN/SD
182	Evaporation	MEAN/MAX/MIN/SD
189	Sunshine duration	MEAN/MAX/MIN/SD
201	Max 2m temperature since last postprocessing	MEAN/MAX/MIN/SD
202	Min 2m temperature since last postprocessing	MEAN/MAX/MIN/SD

The following field is archive only at step=0 and for the control forecast (type=cf):

172

Land/sea mask

The following derived fields are not archived directly, but their monthly statistics are calculated:

207	10m scalar wind speed	MEAN/MAX/MIN/SD
228	Total precipitation	MEAN/MAX/SD

Wave model monthly forecasts are archived as stream WAMF (1095).

In order to retrieve these fields from MARS, two MARS command lines have to be added: method=1, and system=2, but may change, if the monthly forecasting system is modified. Look at the System Change Notice to see which system value is valid. For the control forecast TYPE=CF, for perturbed forecasts TYPE=FC.

Here is an example of MARS retrieval:

retrieve, class="od",expver=0001,stream=mofc,type=fc,method=1,system=2,levtype=pl, level=500,param=Z,number=1/to/50,date=20020327,time=00,step=12/to/768/by/12, target="out"

Weekly Means

Monthly forecast weekly means are calculated for all atmospheric variables and stored in the stream MOFM (1094) and type FCMEAN.

Wave model forecast means (weekly means) are calculated and stored in the stream WMFM (1096).

Monthly forecast weekly maximum (type FCMAX), minimum (type FCMIN) and standard deviation (type FCSTDEV) have also been calculated and archived for all surface fields.

The weeks are as follow:

Week 1: day 5 to day 11 (FCPERIOD=05-11)
Week 2: day 12 to day 18 (FCPERIOD=12-18)
Week 3: day 19 to day 25 (FCPERIOD=19-25)
Week 4: day 26 to day 32 (FCPERIOD=26-32)

Here is an example of MARS retrieval for weekly means:

retrieve, class="od",expver=0001,stream=mofm,type=fc,method=1,system=2,levtype=pl, level=500,param=Z,number=1/to/50,date=20020327, time=00, fcperiod=05-11, target="out"

Ensemble means and standard deviation

Ensemble means and standard deviations are archived in MARS only for a limited number of fields: temperature at 850 and 500 hPa and geopotential at 1000 and 500 hPa.

To retrieve these fields, stream=MOFC, TYPE=EM (ensemble mean) or TYPE=ES (ensemble standard deviation).

example:

class=od,expver=0001,stream=mofc,type=em,method=1,system=2,levtype=pl,level=500, param=Z,date=20020327,time=00,step=24, target="out"

EPSgrams

In order to avoid retrieving 51 members to create EPSgrams, several fields have been reordered, and the minimum, 25%, median, 75% and maximum of the ensemble distribution have been archived. These fields are: T850, total cloud cover, 2-metre temperature, total precipitation and 10 metre scalar wind speed.

To retrieve these fields: STREAM=MOFC, TYPE=ED, NUMBER=0 (minimum), NUMBER=12 (25%), NUMBER=25 (MEDIAN), NUMBER=37 (75%) or NUMBER=50 (MAXIMUM)

example:

class=od,expver=0001,stream=mofc,type=ed,method=1,system=2,number=25,levtype=pl, level=500,param=Z,date=20020327,time=00,step=24, target="out"

Monthly archive of ocean fields:

Ocean fields in the coupled forecasts:

The ocean data are archived together with the atmospheric data, and are distinguished by the 'LEVTYPE' attribute, which is set to 'DEPTH' or 'DP'. Ocean variables are archived as instantaneous fields (product=inst), accumulated fields (product=tacc) or time series (product=tims). The fields are archived along horizontal (section=h), meridional (section=m) or zonal sections (section=z).

Ocean fields in the accelerated forecast:

Fluxes and ocean data created during the 12 days of ocean real-time forecast ( to create the ocean initial conditions) are stored on MARS under TYPE=OF (ocean fields) and FF (forcing fields).

Monthly archive of ocean fields:

Ocean data is output in different sections, H = horizontal, Z = zonal, M = meridional. There are also sections that include the time dimension: Z=longitude-time, M=latitude-time and V=depth-time. Each of these sections is a two-dimensional field, with a particular orientation in space and time. Each forecast ensemble member archives the output listed below. The ocean data is archived together with the atmosphere data, and is distinguished by the 'LEVTYPE' attribute, which is set to 'DEPTH' or 'DP'.

The following instantaneous fields are written every 24 hours. They should allow a rough estimate of drift in the ocean, and give a snapshot of any numerical problems.

Horizontal fields are:

Section	Code	Depth	Name
H	129	5/425	Potential temperature
H	130	5/425	Salinity
H	131	5	u-velocity
H	132	5	v-velocity
H	145	0	Sea-level
H	148	0	Mixed-layer depth
H	133	225	w-velocity

Vertical zonal sections are:

Section	Code	Latitude	Name
Z	129	0	Potential temperature
Z	130	0	Salinity
Z	131	0	u-velocity
Z	132	0	v-velocity
Z	133	0	w-velocity

Vertical meridional sections are:

Section	Code	Longitude	Name
M	129	220	Potential temperature
M	130	220	Salinity
M	131	220	u-velocity
M	132	220	v-velocity
M	133	220	w-velocity

The following accumulated fields are written once per month during the forecasts. Monthly means can be derived from them. They are the main fields for diagnosing the oceanic behaviour of the coupled model forecasts.

Accumulated horizontal fields are:

Section	Code	Depth	Name
H	129	5	Potential temperature
H	130	5	Salinity
H	131	5	u-velocity
H	132	5	v-velocity
H	145	0	Sea level
H	148	0	Mixed layer depth
H	163	0	Depth of 20 deg isotherm
H	164	0	T averaged over upper 300m
H	175	0	S averaged over upper 300m
H	153	0	Zonal wind stress
H	154	0	Meridional wind stress
H	156	0	Net surface heat flux
H	157	0	Absorbed solar radiation
H	158	0	Precipitation - Evaporation

Accumulated vertical zonal sections are:

Section	Code	Latitude	Name
Z	129	0	Potential temperature
Z	130	0	Salinity
Z	131	0	u-velocity
Z	133	0	w-velocity

Accumulated vertical meridional sections are:

Section	Code	Longitude	Name
M	129	60E/90E/165E/180/140W/95W/30W/10W	Potential temperature
M	130	60E/90E/165E/180/140W/95W/30W/10W	Salinity
M	131	60E/165E/140W/30W	u-velocity
M	132	60E/165E/140W/30W	v-velocity
M	133	60E/165E/140W/30W	w-velocity
M	138	60E/165E/140W/30W	Potential density

Several so-called time series fields are also produced. These allow detailed examination of the evolution of certain fields along given lines of latitude or longitude. In all cases the temporal resolution is daily.

Lines of latitude are:

Section	Code	Depth	Latitude	Name
Z	129	5	0	Potential temperature
Z	131	5	0	U velocity
Z	145	0	0	Sea level
Z	163	0	0	Depth of 20 deg isotherm
Z	153	0	0	Zonal wind stress
Z	164	0	8N/5N/0/5S/8S	T averaged over upper 300m

Lines of longitude are:

Section	Code	Depth	Longitude	Name
M	129	5	180/60W	Potential temperature
M	145	0	180/60W	Sea level
M	148	0	180/60W	Mixed layer depth

Finally, a small selection of instantaneous fields is output daily, to allow study of the evolution of the system on synoptic timescales. The fields concerned are:

Section	Code	Depth	Name
H	129	5	Potential temperature
H	145	0	Sea level
H	148	0	Mixed layer depth
M	129	0	Potential temperature

Monthly archive of ocean fields (accelerated forecast):

Since the ocean analysis lags about 12 days behind real time, the ocean model is integrated from the last ocean analysis forced by analysed wind stress, heat fluxes and P-E. During this "ocean forecast", the sea surface temperature is relaxed towards persisted SST, with a damping rate of 100W/m²/K.

Forcing fields (TYPE=FF):

The time-averaged fields used to force the ocean during the 12 days of ocean integration are archived on MARS:

Section	Code	Depth	Name
H	157	0	Absorbed solar radiation
H	161	0	Diagnosed sea surface temperature error
H	162	0	Heat flux correction
H	156	0	Net surface heat flux
H	129	0	Ocean potential temperature
H	158	0	Precipitation-evaporation
H	159	0	Specified sea-surface temperature
H	160	0	Specified surface heat flux
H	153	0	u stress
H	154	0	v stress

Ocean Fields (TYPE=OF):

Same fields as for the operational ocean analysis. The list includes all the fields stored during coupled integrations but with a much larger number of levels, longitude and latitude lines.

Stand alone Ocean Analysis

The main purpose of the ocean analysis is to provide initial conditions for the extended range forecasts (seasonal and monthly). There are two streams: The re-analysis stream spans the period 1959 up to 11 days behind real time whereas the real-time stream started in August 2006. > System 3 Ocean Analysis documentation

Monthly and climatology datasets

ECMWF maintains an archive of monthly means data from the atmospheric and wave model archive. The resolution and internal representation of the archive may change according to changes in ECMWF's operational practice.

Atmospheric Analysis monthly means are averaged over the calendar month for each of the synoptic times 00, 06, 12 and 18 UTC.
Atmospheric Forecast monthly means: are the average of all the forecasts for a particular step that verify in the selected calendar month. All monthly means are archived at model resolution.
Wave Analysis monthly means: are averaged over the calendar month for each of the synoptic times 00, 06, 12 and 18 UTC.
Wave forecast monthly means: are the average of all the forecasts for a particular step that verify in the selected calendar month. Wave Monthly means are archived at 1.5 degree resolution.

There is a limited climatology data set, which contains the Geopotential and Temperature on Pressure Levels for each month of the year. The data originally came from NCEP, Washington, and it was processed to store it in MARS. Although it is available to users, it is recommended that modern applications use the Monthly means archive or the Re-Analysis Monthly means archive for climatology purposes.

ECMWF reanalyses

ECMWF periodically uses its forecast models and data assimilation systems to 'reanalyse' archived observations, creating global data sets describing the recent history of the atmosphere, land surface, and oceans. Reanalysis data are used for monitoring climate change, for research and education, and for commercial applications.

Available ECMWF reanalysis datasets include: analysis, forecast and forecast accumulations as output from atmospheric models, as well as analysis and forecast from a wave-model reanalysis. There is also a Monthly Means data set containing data at the resolution of the data assimilation and forecast system used by each reanalysis.

Special datasets

MACC Monitoring Atmospheric Composition & Climate > see in MARS Catalogue
Sub-seasonal to seasonal prediction project (S2S) S2S is a WWRP/THORPEX-WCRP joint research project established to improve forecast skill and understanding on the sub-seasonal to seasonal time scale, and promote its uptake by operational centres and exploitation by the applications community > see in MARS Catalogue
TIGGE The International Grand Global Ensemble is a key component of THORPEX: a World Weather Research Programme to accelerate the improvements in the accuracy of 1-day to 2 week high-impact weather forecasts for the benefit of humanity. Global ensemble forecasts to around 14 days generated routinely at different centres around the world. Currently data from ECMWF, JMA (Japan), Met Office (UK), CMA (China), NCEP (USA), MSC (Canada), Météo-France, BOM (Australia), CPTEC (Brazil) and KMA (Korea) is archived. > see in MARS Catalogue
DEMETER is the acronym of the EU-funded project "Development of a European Multi model Ensemble system for seasonal to inTERannual prediction" . The objective of the project is to develop a well-validated European coupled multi-model ensemble forecast system for reliable seasonal to inter annual prediction. Six comprehensive European global coupled atmosphere-ocean models are being installed at ECMWF, those of: ECMWF, Météo-France, LODYC, Met Office, MPI, INGV, INM-HIRLAM and CERFACS. > see in MARS Catalogue
Data Targeting System A pre-operational Data Targeting System (DTS) will be developed to assess the feasibility of operational adaptive control of the observing system and as a facility to aid research projects using data targeting. The DTS will be developed and hosted at ECMWF. The work is jointly funded by EUCOS and the EC as part of the PREVIEW Integrated Project (work package WP3320) of the EU 6th Framework Programme. A real-time trial of the DTS will run between February and December 2008. > see in MARS Catalogue
ECSN -HIRETYCS is the European Climate Support Network. HIRETYCS is the High Resolution Ten Year Climate Simulation. This data set consist of 10-year climate simulations produced at three centres: Centre National de Recherches Météorologiques (CNRM), Max-Planck Institute (MPI) and United Kingdom Met Office. > see in MARS Catalogue
ELDAS ECMWF is a participant in the Development of a European Land Data Assimilation System to predict Floods and Droughts (ELDAS) project funded by the European Union. > see in MARS Catalogue
ENSEMBLES The EU-funded ENSEMBLES project intends to develop an ensemble prediction system for climate change based on the principal state-of-the-art, high resolution, global and regional Earth System models developed in Europe, validated against quality controlled, high resolution gridded datasets for Europe, to produce for the first time, an objective probabilistic estimate of uncertainty in future climate at the seasonal to decadal and longer timescales. A large set of seasonal, annual and decadal hindcasts is available which have been produced with different forecast systems run by ECMWF, Météo-France, Met Office, IfM, INGV and CERFACS. These systems addressed the important problem of the impact of model uncertainty on forecast error by using the multi-model, stochastic physics and perturbed parameters approaches. > see in MARS Catalogue
EURO4M European Reanalysis and Observations for Monitoring project is a EU funded project that provides timely and reliable information about the state and evolution of the European climate. It combines observations from satellites, ground-based stations and results from comprehensive model-based regional reanalyses. By closely monitoring European climate, climate variability and change can be better understood and predicted. > see in MARS Catalogue
MERSEA Development of a European system for operational monitoring and forecasting of the ocean physics, biogeochemistry, and ecosystems, on global and regional scales > see in MARS Catalogue
NOAA/CIRES 20th Century Reanalysis version II > see in MARS Catalogue

PROVOST stands for Prediction Of climate Variations On Seasonal to inter annual Time scales. They are a set of experiments from four centres: ECMWF, Météo-France, EDF and Met Office. The experiments are 120 day runs from 9 consecutive starting days, with write-ups every 24 hours of Pressure level and Surface data. > see in MARS Catalogue

1.0 Experiments

Experiment data from four centres: ECMWF, Meteo France, EDF and UKMO. The experiments are 120 day runs from 9 consecutive starting days, with writeups every 24 hours, pressure level and surface data.

A common parameter table and a common GRIB format have been used by all the centres. The same originating centre has been coded in the GRIB header (98=ECMWF), and a sub-centre identifier is used:

240, ECMWF
241, Meteo France
242, EDF
243, UKMO

2.0 Parameter table

A new common parameter table has been used which contains only the parameters agreed for comparison between centres.

TABLE 1. ECMWF local Code Table 2, Version Number 170

Code	Mars	Field	Units
129	Z	Geopotential	m2 s-2
130	T	Temperature	K
131	U	U-velocity	m s-1
132	V	V-velocity	m s-1
138	VO	Vorticity (relative)	s-1
140	SWL1	Soil wetness level 1	m
149	TSW	Total soil moisture	m
151	MSL	Mean sea level pressure	Pa
155	D	Divergence	s-1
171	SWL2	Soil wetness level 2	m
179	TTR	Top thermal radiation	W m-2
184	SWL3	Soil wetness level 3	m
201	MX2T	Maximum temp. at 2m since previous post-processing	K
202	MN2T	Minimum temp. at 2m sonce previous post-processing	K
228	TP	Total precipitation	m

3.0 ECMWF stored data

3.1 Single level

Parameters:

139/140/141/142/143/146/147/151/164/171/176/177/179/180/181/182/184/201/202

Surface parameters are different in 1979/80 spring, summer and winter, viz

139/140/141/142/143/146/147/151/164/176/177/179/180/181/182/185/201/202

Surface parameters for autumn are different are different from those in spring, summer and winter, viz

139/140/141/142/143/146/147/151/164/176/177/179/180/181/182/185/201/202/237

3.2 Pressure levels

Levels:

1000/925/850/700/500/400/300/250/200/150/100/70/50/30/10

Parameters:

129/130/133/135/138/155/157

TABLE 2. ECMWF seasonal forecast data

Date	79	80	81	82	83	84	85	86	87	88	89	90	91	92	93
20/02	X	-	X	X	X	-	X	X	X	-	X	X	X	-	X
21/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
22/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
23/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/02	-	X	-	-	-	X	-	-	-	X	-	-	-	X	-
.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.
23/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
30/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
31/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.
23/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
30/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
31/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.
22/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	-
23/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	-
24/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	-
25/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	-
26/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	-
27/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	-
28/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	-
29/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	-
30/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	-

X = pressure level and surface fields archived, - = not available

3.3 MARS retrieval

3.3.1 Single level

RETRIEVE,

CLASS = RD,

TYPE = FC,

EXPVER = "SCWF",

LEVTYPE = SFC,

REPRES = GG,

PARAM = 139/140/141/142/143/146/147/151/164/171/176/177/179/180/181/182/184/201/202

DATE = yyyymmdd,

TIME = 1200,

STEP = 0/24/...,

TARGET = "myfile"

3.3.2 Pressure levels

          
RETRIEVE,

CLASS = RD,

TYPE = FC,

EXPVER = "SCWF",

LEVTYPE = PL,

LEVEL = 1000/925/850/700/500/400/300/250/200/150/100/70/50/30/10,

PARAM = 129/130/133/135/138/155/157,

REPRES = SH,

DATE = yyyymmdd,

TIME = 1200,

STEP = 0/24/...,

TARGET = "myfile"

4.0 Meteo France stored data

4.1 Single level

Parameters:

129/141/149/151/172/179/201/202/228

4.2 Pressure levels

Levels:

850/700/500/200

Parameters:

129/130/138/155

Not all parameters are available at all levels:

- 129 is available at 700/500/200

- 130 is available at 850/500/200

- 138 is available at 850/200

- 155 is available at 850/200

TABLE 3. Meteo France seasonal forecast data

Date	79	80	81	82	83	84	85	86	87	88	89	90	91	92	93
20/02	X	-	X	X	X	-	X	X	X	-	X	X	X	-	X
21/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
22/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
23/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/02	-	X	-	-	-	X	-	-	-	X	-	-	-	X	-
.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.
23/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
30/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
31/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.
23/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
30/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
31/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.
22/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
23/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
30/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X

X = both pressure level and surface fields archived, - = not to be archived

4.3 MARS retrieval

4.3.1 Single level

          
RETRIEVE,

CLASS = RD,

TYPE = FC,

EXPVER = "SMEF",

LEVTYPE = SFC,

PARAM = 129/141/149/151/172/179/201/202/228,

DATE = yyyymmdd,

TIME = 1200,

STEP = 0/24/48/...,

TARGET = "myfile"

4.3.2 Pressure levels

          
RETRIEVE,
CLASS = RD,
TYPE = FC,
EXPVER = "SMEF",
LEVTYPE = PL,
LEVELIST = 850/700/500/200,
PARAM = 129/130/138/155,
DATE = yyyymmdd,
TIME = 1200,
STEP = 0/24/48/..,
TARGET = "myfile"

5.0 EDF stored data

5.1 Single level

Parameters:

129/141/149/151/172/179/201/202/228,

5.2 Pressure levels

Levels:

850/700/500/200

Parameters:

129/130/138/155

Not all parameters are available at all levels:

- 129 is available at 700/500/200

- 130 is available at 850/500/200

- 138 is available at 850/200

- 155 is available at 850/200

TABLE 4. EDF seasonal forecast data

Date	79	80	81	82	83	84	85	86	87	88	89	90	91	92	93
22/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
23/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
30/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X

X = both pressure level and surface fields archived

5.3 MARS retrieval

5.3.1 Single level

RETRIEVE,

CLASS = RD,

TYPE = FC,

EXPVER = "SEDF",

LEVTYPE = SFC,

PARAM = 129/141/149/151/172/179/201/202/228,

DATE = yyyymmdd,

TIME = 1200,

STEP = 0/24/48/...,

TARGET = "myfile"

5.3.2 Pressure levels

RETRIEVE,

CLASS = RD,

TYPE = FC,

EXPVER = "SEDF",

LEVTYPE = PL,

LEVELIST = 850/700/500/200,

PARAM = 129/130/138/155,

DATE = yyyymmdd,

TIME = 1200,

STEP = 0/24/48/..,

TARGET = "myfile"

6.0 UKMO stored data

6.1 Single level

Parameters:

130/140/141/149/151/179/201/202/228

6.2 Pressure levels

Levels:

850/700/500/200

Parameters:

129/130/131/132

Not all parameters are available at all levels:

- 129 is available at 700/500/200

- 130 is available at 850/500/200

- 131 is available at 850/200

- 132 is available at 850/200

TABLE 5. UKMO seasonal forecast data

Date	79	80	81	82	83	84	85	86	87	88	89	90	91	92	93
20/02	X	-	X	X	X	-	X	X	X	-	X	X	X	-	X
21/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
22/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
23/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/02	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/02	-	X	-	-	-	X	-	-	-	X	-	-	-	X	-
.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.
23/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
30/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
31/05	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.
23/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
30/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
31/08	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
.	.	.	.	.	.	.	.	.	.	.	.	.	.	.	.
22/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
23/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
24/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
25/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
26/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
27/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
28/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
29/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
30/11	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X

X = pressure level and surface fields archived

- = not to be archived

6.3 MARS retrieval

For this data stream, EXPVER = "SUKM" must be used.

6.3.1 Single level

RETRIEVE,

CLASS = RD,

TYPE = FC,

STREAM = 2243,

EXPVER = "SUKM",

LEVTYPE = SFC,

REPRES = LL,

DOMAIN = G,

PARAM = 130/140/141/149/151/179/201/202/228,

DATE = yyyymmdd,

TIME = 1200,

STEP = 24/48/...,

TARGET = "myfile"

6.3.2 Pressure levels

RETRIEVE,

CLASS = RD,

TYPE = FC,

STREAM = 2243,

EXPVER = "SUKM",

LEVTYPE = PL,

LEVELIST = 850/700/500/200,

PARAM = 129/130/131/132,

REPRES = LL,

DOMAIN = G,

DATE = yyyymmdd,

TIME = 1200,

STEP = 24/48/...,

TARGET = "myfile"

TOST is the THORPEX Observing System Test, an experiment carried out at the end of 2003 to evaluate targeted observations in an Ensemble Prediction System. There is output from 3 different models, ECMWF, Météo-France and United Kingdom Met Office. > see in MARS Catalogue
YOPP Year Of Polar Prediction > see in MARS Catalogue
YOTC Year of tropical convection > see in MARS Catalogue

TOGA is an archive of level III-A atmospheric data to support the World Climate Research Program (WCRP) core project Tropical Ocean and Global Atmosphere (TOGA). This archive accommodates the 10 year period beginning 1 January 1985, fulfilling ECMWF's role as a TOGA Data Centre. The production of this archive has been discontinued only on 29/2/2016. > see in MARS Catalogue

ECMWF created an archive of level III-A atmospheric data in support of projects associated with the World Climate Research Program (WCRP). This archive accommodated the 10 year period beginning 1 January 1985, fulfilling ECMWF's role as a Tropical Ocean and Global Atmosphere (TOGA) Level III Atmospheric Data Centre. The production has been discontinued on 29/2/2016 for type AN and on 22/5/2016 for type FC. .

The Level III-A archive is subdivided into three classes of data sets:

The data sets are based on quantities analysed or computed within the ECMWF data assimilation scheme or from forecasts based on these analyses.

The Basic Data Set contain selected analysed values in a compact form at a resolution of 2.5° x 2.5°. They are particularly suitable for users with limited data processing resources. Derived quantities (fluxes, etc.) are not included, but can in principle be calculated from the data provided in the data sets.

The Supplementary Fields Data Set contains additional surface data, fluxes and net radiation data derived from short-range forecasts used as first-guess data for the analyses. Most of the fields in this data set contain values accumulated over the first 6 (or 12) hours of the forecast. The exceptions, total cloud cover fields, contain instantaneous 6 (or 12) hour forecast values. This is a subset of the operational first-guess surface data.

The Extension Data Set contains additional surface data, fluxes, net radiation data and precipitation derived from 24-hour forecast values. All the fields in this data set contain values accumulated between time step 12 and time step 36 of the forecast.

The archive is currently maintained using the WMO FM 92-IX Ext GRIB (grid in binary) form of data representation, with ECMWF local versions of GRIB Table 2. All fields of data are global within the archive.

A full extraction service is supported, enabling users to obtain sub-areas of data and data at various resolutions on regular Gaussian or latitude/longitude grids, or as spherical harmonics with selected triangular truncation. All extracted data are delivered using the GRIB representation.

TOGA Basic Level III-A Data Sets

These data sets contain uninitialised analysis values interpolated to a 2.5° x 2.5° regular latitude/longitude grid. This grid is co-located with the 5° x 5° and 2.5° x 2.5° grids used for ECMWF data distribution daily on the Global Telecommunications System (GTS).

Three data sets are separately supported:

a Surface Data Set
an Upper-Air Data Set
a Consolidated Data Set.

For each data set the following is relevant:

period supported - 1 January 1985 to current date;
fields are uninitialised analyses for 0000 UTC and 1200 UTC each day;
each parameter at each level is stored as a field of grid point values on a 2.5° x 2.5° regular rectangular mesh 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 analysis methods used;
production of the archive has been made as automatic as possible using techniques which enable the data sets to be updated monthly.

The Surface Data Set contains

1 January 1985

surface pressure, soil temperature level 1, MSL pressure, u- and v-components of wind at 10m, temperature at 2m, dewpoint at 2m, surface geopotential and land-sea mask.

The Upper-Air Data Set contains :

1 January 1985	14 standard pressure levels, 1000, 850, 700, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30 and 10 hPageopotential, temperature, vertical velocity, u- and v-components of horizontal wind, and relative humidity at each level
1 January 1992	pressure level, 925 hPa added
1 April 1999	pressure levels 20, 7, 5, 3, 2 and 1 hPa added

Since the Upper-Air Data Set is separately maintained from the Surface Data Set, separate requests must be made for each, and the extracted data cannot be interspersed.

The Consolidated Data Set contains data corresponding to the Upper-Air Data Set together with data comprising the Surface Data Set.

The mode of storage of the Consolidated Data Set within the archive is such that data must be retrieved globally, for all parameters, all levels, and in monthly units.

1 January 1985

Surface data is surface pressure, soil temperature level 1, MSL pressure, u- and v-components of wind at 10m, temperature at 2m, dewpoint at 2m, surface geopotential and land-sea mask

Upper air data is 14 standard pressure levels, 1000, 850, 700, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30 and 10 hPa

geopotential, temperature, vertical velocity, u- and v-components of horizontal wind, and relative humidity at each level

1 January 1992

pressure level, 925 hPa added

1 April 1999

pressure levels 20, 7, 5, 3, 2 and 1 hPa added

TOGA Supplementary Data Sets

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)

TOGA Extension Data Sets

The Extension Data Set has been created to supplement the data available from the ECMWF/WCRP Data Archive. This data set is based on 24-hour forecast data from the ECMWF model. 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 Extension Data Set is defined as:

period supported 1 January 1991 to current date;
fields are 24-hour accumulated forecast values based on the 12 to 36-hour forecast steps, The forecast used for this archive commences at 1200 UTC and this archive is based on steps 12 and 36 of the forecast, so the archive is really accumulated values for the day following that given in the GRIB Section 1 header;
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 1991	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) fields available are large scale precipitation, convective precipitation, snowfall, 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, latitudional component of gravity wave stress, meridional component of gravity wave stress, total precipitation
17 September 1991	Internal data representation is in an N160 Quasi-regular Gaussian grid (160 lines between the pole and the equator, with varying numbers of points along each row)
14 May 1997	fields added are surface thermal radiation downward, surface solar radiation downward
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)

How to reproduce TOGA data

The TOGA archive has been discontinued on 29/2/2016. To reproduce this dataset, the following MARS requests can be used:

Surface:

retrieve,
class =od,
stream=oper,
type=an,
levtype=sfc,
date=$date,
time= 00 : 00 : 00 / 12 : 00 : 00 ,

param= 129.128 / 134.128 / 139.128 / 151.128 / 165.128 / 166.128 / 167.128 / 168.128 / 172.128 ,

accuracy= 16 ,
grid= 2.5 / 2.5 ,

Pressure levels:

retrieve,
class =od,
stream=oper,
type=an,
levtype=pl,
date=$date,
time= 00 : 00 : 00 / 12 : 00 : 00 ,

levelist= 1 / 2 / 3 / 5 / 7 / 10 / 20 / 30 / 50 / 70 / 100 / 150 / 200 / 250 / 300 / 400 / 500 / 600 / 700 / 800 / 850 / 900 / 925 / 950 / 1000 ,
param= 129.128 / 130.128 / 131.128 / 132.128 / 135.128 / 157.128 ,

accuracy= 16 ,
grib= 2.5 / 2.5 ,

And the extended data can be obtained from the Operational forecast using time 12 step 36 - step 12. Note that there are two groups of accumulated parameters:

LSP/CP/SF/TP, which can not be negative
BLD/SSHF/SLHF/SSRD/STRD/SSR/STR/TSR/TTR/EWSS/NSSS/E/LGWS/MGWS

retrieve,
type = fc,
stream = oper,
levtype = sfc,
repres = gg,
param = lsp/cp/sf/tp,
date = 2016-05-21,
time = 12,
step = 36,
grid = av,
fieldset = datap_36
 
retrieve,
step = 12,
fieldset = datap_12
 
compute,
fieldset = diffp,
accuracy = av,
formula = "datap_36-datap_12"
 
compute,
formula = "(diffp<0)*0 + (diffp>0)*diffp",
target = "toga.grib"
 
retrieve,
param = bld/sshf/slhf/ssrd/strd/ssr/str/tsr/ttr/ewss/nsss/e/lgws/mgws,
step = 36,
fieldset = dataf_36
 
retrieve,
step = 12,
fieldset = dataf_12
 
compute,
formula = "dataf_36-dataf_12",
target = "toga.grib"

To also modify the grib message header to be the same than TOGA, you can use grib_set:

grib_set -s stream=toga,P1= 12 ,P2= 36 ,timeRangeIndicator= 5 ,generatingProcessIdentifier= 146 toga.grib toga_new.grib

Research experiments

A vast amount of data is archived daily containing IFS (Integrated Forecast System) experiments produced by ECMWF's Research Department or by Member States' users at ECMWF. Basically, an experiment can address any area of meteorology and it is archived accordingly. Users wanting to retrieve Research experiments need to know in advance the name of the specific experiment and its nature. For this information please, contact User Support.

Member States projects

Some Member States also archive output other than from IFS into MARS. One example of such activity is the COSMO-LEPS forecast suite, running daily at ECMWF.

Input data to ECMWF models or for verification/scores

Fields

ECMWF archives a selection of products, both Analysis and Forecast, from other Centres: Exeter, Melbourne, Montreal, Offenbach, Toulouse, Tokyo and Washington. Most of these products exist on the GTS and they are combined to create global fields with ECMWF local GRIB header extensions added. A convention exists to create empty (dummy) fields when there are missing data (e.g. if problems arise at one of the Centres or on the GTS).

There are other fields which are used as input for the ECMWF forecasting system (e.g. Sea Surface Temperatures from Washington which are used by ECMWF's Analysis).

Images from Meteosat and GOES Satellites are coded in GRIB and archived in MARS.

Observations

Observations used as input to the assimilation system are also archived in MARS, as well as the Feedback on how the observations are used in the analysis. There are, amongst others:

Surface data, conventional and satellite data covering: synoptic observations, soil and earth temperature, buoy information and PAOB observations (pseudo surface pressure observations in the Southern Hemisphere).
Vertical soundings, conventional and satellite data: PILOT, TEMP, ROCOB, RTOVS, ATOVS, SATEM.
Upper-air data, conventional observations such as AIREP and ACARS, together with satellite upper-air SATOB, high resolution winds and geostationary radiances.

MARS also holds the observations in the form of files as they are presented to the Analysis (Analysis Input), as well as the feedback files (Analysis Feedback). These are mainly used to allow to reproduce in the future any past operational run. There is one set of files per synoptic time.

Data formats

Archived data is stored in two WMO formats: GRIB for fields and BUFR for observations. In addition, observation feedback is archived in the ECMWF/IFS format ODB (Observational Data Base). In general, the retrieved data is returned in the archive format. However, with the Data Server or the Web API it is possible to request fields to be returned in netCDF format.

WMO FM 92-IX Ext GRIB

GRIB (General Regularly-distributed Information in Binary form) is a WMO defined format for meteorological field data, or (more generally) any regularly spaced gridded data. All ECMWF model output is in GRIB format with ECMWF local extensions in their headers. The GRIB format is handled via the ecCodes software. Fields are archived in one of the following spatial coordinate systems:

Spherical Harmonics (SH) mainly for upper air fields

Gaussian Grid (GG) mainly for surface data, although some upper air fields as well

Latitude/Longitude (LL) other centre's data, wave and ocean data

For the correspondence between the three types of grid resolutions see the following table

The correspondence between the spectral resolution, the reduced Gaussian grid and the approximate latitudinal resolution is listed in the table below. In column "Spectral" T denotes the truncation number. The reduced Gaussian grids are specified by the number of lines between the Pole and Equator, preceded by N for the ECMWF original reduced Gaussian grid and O for the octahedral ECMWF reduced Gaussian grid. The octahedral grid has first been introduced on 8 March 2016 to the operational high resolution and ensemble datasets.

Correspondence between resolutions of ECMWF grid types
Spectral	Gaussian	Lat/Lon
T63	N48	1.875
T106	N80	1.125
T159	N80	1.125
T213	N160	0.5625
T319	N160 O320	0.5625 0.28125
T511	N256	0.351
T639	N320 O640	0.28125 0.141
T799	N400	0.225
T1023	N512	0.176
T1279	N640 O1280	0.141 0.070

WMO FM-94 BUFR

BUFR (Binary Universal Form for the Representation of meteorological data) is a WMO defined format for point data (irregularly spaced), which is used for archived observations. The BUFR format is handled via BUFREX and other subroutines provided by the ECMWF BUFRDC software.

ODB

In the IFS observations are handled by ODB (Observational Data Base).

ODB is a

Hierarchical in-core database with a data definition and query language: ODB/SQL
A data format
...

ODB Observation Feedback (ofb) data is archived in MARS to improve its representation in the MARS meta data. ODB also introduces SQL capabilities to request feedback data.

To improve the handling of observations, ODB will be further integrated into ECMWF systems

See ODB API for more details.