...
The impact of the new cycle on the performance of the forecasting system has been tested in research mode during the period 1 January to 10 May 2011, and in pre-operational runs since 11 May 2011. The new cycle shows benefit in terms of objective upper-air scores in the early forecast range in both hemispheres: the geopotential scores are improved throughout the troposphere, with some degradation at the 100 hPa level. Tropical wind scores in the lower troposphere are significantly improved, specifically leading to reduced systematic errors in the strength of the low level inflow to the African and Indian monsoons. The change in surface roughness has led to reduced 10m wind speed over land and reduced diurnal amplitude in T2m, both of which result in generally reduced bias against observations. Cold biases in T2m have been reduced in specific winter-time situations where the amount of super-cooled cloud-water has been increased. The main impact on the EPS is improved probabilistic scores for the tropical winds throughout the forecast range.
Newsletter No.130 Winter2011/12: news items on pages 4 and 13-14
...
Users of ECMWF’s web pages may have noticed that most of the displayed forecast charts are now being produced with the new version of the ECMWF visualisation software, Magics++.