Mean sea-level pressure and related indices from control and tropical relaxation winter seasonal hindcasts using the Met Office GloSea5 system.

© Crown Copyright, Met Office

The accompanying data is made available under the terms of the Non-Commercial Government Licence (http://www.nationalarchives.gov.uk/doc/non-commercial-government-licence/version/2/).

These data are the results of ensemble modelling simulations using the Met Office GloSea5 numerical seasonal prediction system. Files in (zipped) netcdf format contain winter seasonal-mean mean sea-level pressure (MSLP) fields for each member of specified ensemble and hindcast winter (December-February from 1993-94 to 2015-16). The files are named according to the specification of relaxation towards observational reanalysis in each. HCAST has no relaxation, ALL has tropical (approximately 22.5S to 22.5N) relaxation at all atmospheric heights, TROP is similar to ALL but with relaxation limited to below 18km and STRAT is similar to ALL but with relaxation limited to above 18km. The relaxation is designed to constrain the atmospheric state to be close to that which was observed within the domain over which it is applied. Details of the technique can be found in Maidens et al., 2021* and references therein.

An additional text file is provided to give summary statistics of key MSLP-based winter indices.

* Maidens, A., Knight, J. R., &  Scaife, A. A. (2021). Tropical and stratospheric influences on winter atmospheric circulation patterns in the North Atlantic sector. Environmental Research Letters, 16, 024035. https://doi.org/10.1088/1748-9326/abd8aa