This dataset contains a range of model output from both operational runs of the European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS) CY45R1 model forecasts and hindcasts and output from specific experimental runs.

These data were produced to support the article "Forecast-based attribution of a winter heatwave within the limit of predictability" (see citation and link to paper elsewhere on this record).

Within the archived products the directory tree structure is as follows:

Top level domain splitting:

>EU

Model data at 0.25 degree resolution for the region contained within (33 to 73.5N / -27 to 45E).

>GLOB

Model data at 0.25 degree resolution for the full globe.

Below which there are sub-directories as follows (note, M-climate is only available for the EU domain):

>>ENS​

Data from the operational Ensemble Prediction System (EPS) forecast.

>>M-climate

Data from EPS hindcasts used to construct model climate. See https://confluence.ecmwf.int/display/FUG/M-climate%2C+the+ENS+Model+Climate.

>>pi-CO2

Data from EPS forecast that replicates operations *but for* reduced CO2 concentrations, set to 285 ppm.

>>incr-CO2

Data from EPS forecast that replicates operations *but for* increased CO2 concentrations, set to 600 ppm.

Within these runs the data are then available on the following level types:

>>>pl

Data on pressure levels.

>>>sfc

Data on single levels.

Ensemble data are further split into sub-directories as follows:

>>>>cf

Control forecast member.

>>>>pf

Perturbed forecast members.

The specific variables available within each netCDF file can differ depending on the region and experiment type (eg. the operational ENS forecasts whose initialisation dates match those of the perturbed CO2 experiments have more variables available than the others). All the datasets & variables required to reproduce the analysis are described in the paper.

Forecast-based attribution of a winter heatwave within the limit of predictability. Nicholas J. Leach, Antje Weisheimer, Myles R. Allen, Tim Palmer. Proceedings of the National Academy of Sciences Dec 2021, 118 (49) e2112087118; DOI: 10.1073/pnas.2112087118