08:30 UTC | 27 May 2020
The new IFS Cycle 47r1 will be implemented on 30 June 2020.
This cycle includes changes in the treatment of observations, improvements in the data assimilation and to the model. Quintic vertical interpolation in the semi-Lagrangian advection scheme has been introduced as well as the inclusion of a better surface albedo climatology making use of more data from the MODIS instrument. Further information on this new cycle is available at Implementation of IFS Cycle 47r1.
Please note that new metrics of Tropical Cyclone (TC) “size” will be made available to supplement the existing forecasts of TC track and intensity. We encourage users of these BUFR data to test their decoding software. For technical information see New Tropical Cyclone Wind Radii product.
Ahead of the implementation of IFS Cycle 47r1, Director of Forecasts Florian Pappenberger explained the changes and how they will improve forecasts in a webinar on 27 May 2020 at 8.30 UTC and 28 May 2020 at 14.30 UTC. The webinars focused on verification, technical access to the test data and new parameters and products.
The upgrade brings improvements in data assimilation, including developments to the weak constraint 4D-Var and improvements to the initial balance of the analysis. In the model, more accurate vertical interpolation is the advection scheme significantly improves stratospheric performance in a cost-effective manner, and changes to surface drag over the ocean at high wind speeds improve the wind-intensity relationship for tropical cyclones. These and other developments were described.