MJ Martin, Met Office, Exeter, UK. M Balmaseda, ECMWF, Reading, UK L Bertino, NERSC, Bergen, Norway P Brasseur, LEGI, Grenoble, France G Brassington, Bureau of Meteorology, Melbourne, Australia J Cummings, NRL, Monterey, USA Y Fujii, JMA/MRI, Tsukuba, Japan DJ Lea, Met Office, Exeter, UK J-M Lellouche, Mercator Ocean, Toulouse, France K Mogensen, ECMWF, Reading, UK P Oke, CSIRO, Hobart, Austral...

We have developed a Lagrangian air-parcel cirrus model (LACM), to diagnose the processes controlling water in the tropical tropopause layer (TTL). LACM applies parameterised microphysics to air parcel trajectories. The parameterisation includes the homogeneous freezing of aerosol droplets, the growth/sublimation of ice particles, and sedimentation of ice particles, so capturing the main dehydra...

We used a statistical linear model to infer MERRA’s wind speed v t (x ), at time t and on some ECMWF grid point x included in the MERRA grid point x , from MERRA’s estimate v t (x M ): v t (x ) = a E t v M t (x M ) + b E t , where the coefficients a E t and b x t are estimated using ECMWF’s wind speed estimate v E t (x ) as a response variable. This estimation is carried out adaptively on a mon...

The prediction of extratropical cyclones by the European Centre for Medium-Range Weather Forecasts (ECMWF) and the National Centers for Environmental Prediction (NCEP) ensemble prediction systems (EPSs) has been investigated using an objective feature tracking methodology to identify and track the cyclones along the forecast trajectories. Overall the results show that the ECMWF EPS has a slight...

Evaluation of ECMWF water vapour analyses by airborne differential absorption lidar measurements: a case study between Brasil and Europe H. Flentje, A. Dörnbrack, A. Fix, G. Ehret, and E. Hólm Deutscher Wetterdienst, Hohenpeißenberg, Germany DLR Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany European Centre For Medium Range Weather Forecasts, Reading, UK Received: 8 March 2007 – ...