Wind stilling over the continents of the Northern Hemisphere
A study published on 17 October 2010 in the journal Nature Geoscience shows that over the past three decades, surface wind speeds seem to have noticeably decreased in several regions of the world, such as the United States, China, Australia, and in several European countries. Given the often inadequate quality and heterogeneity of wind data measured by anemometers, no long-term study of the evolution of wind speeds on a global scale had been carried out so far.
The Ensemble of Data assimilations and its use in the EPS
On Tuesday, 22 June 2010, ECMWF implemented an Ensemble of Data Assimilations (EDA). The EDA is designed to provide information about the uncertainty in the analysis of atmospheric observations that provides the starting point for ECMWF's forecasts. In this implementation, the output from the EDA is used to improve the representation of initial-time uncertainty in the forecasts of the Ensemble Prediction System (EPS). The result is a more reliable estimation of forecast uncertainty.