ERA-40 Monitoring

Monitoring Observations

Data coverage maps both from conventional and satellite observations are presented.
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Monitoring Analyses

A selection of ERA-40 monitoring statistics is presented. Time-evolutions of both the first guess and the analyzed fields together with the analyses increment (analyses-minus-first guess) normally show relatively smooth behaviour from day to day. On global scale a jump is an indication of a possible problem with the observations or in their use by the analyses.
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Monitoring Satellites

The use of satellite radiance data in the assimilation is monitored by so called 'radgrams'. The mean departures of the observed radiances and the radiances calculated from the temperature and humidity profiles of the model at each radiance spot are plotted as a blue curve. The mean departures of the observed radiances after tuning is plotted as a red curve with one STD on each side as a dotted curve. Not all channels are used in the assimilation e.g HIRS-9 (O3 channel) has large departures since it is not used and it is not tuned.
The instruments currently used are:

Monitoring Monthly

Here you will find four selections of monthly mean maps and cross sections from the most recently finished month.

In 'Flux' daily mean forecasts (+24h minus +12h) of the water, energy and momentum fluxes are shown. These quantities are of course not analyzed, but derived from the model integration.

'Surf' contains maps of soil, surface, near-surface andvertically integrated variables. Most of them are analyzed - 2-metre and soil parametres, ozone and precipitable water content - while the total cloud amount is diagnosed by the model.

In 'Plev' a small selection of pressure level fields are shown. The vertical velocity at 500 hPa and the divergent winds are not analyzed directly, but diagnosed from the wind analyses. To see the direction of weak mean winds better, the wind arrows at 200 and 850 hPa are not proportional to the windspeed

Zonal and monthly mean cross sections are seen in 'Xsect'.

All earlier months in the stream are also available - click on Archive.
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