Season of attribution: present-day forecasts replicating operations II

Title Season of attribution: present-day forecasts replicating operations II
Description Forecasts using IFS EPS CY47R3b replicating operations (51 members, TCo639, ORCA025Z75). These forecasts were run after the HPCF move to Bologna on the ATOS system, and therefore are not necessarily bit-identical to the operational forecasts at the time - but are statistically equivalent. These forecasts are part of a series of perturbed forecast experiments designed to explore and quantify human influence on exterme weather. For more technical information on the experiment design, please see 'Heatwave Attribution Using Reliable Operational Weather Forecasts', Leach et al., 2024 (https://doi.org/10.1038/s41467-024-48280-7). This 'Season of Attribution' covers the 2022-23 Northern Hemisphere winter, with 14-day forecasts initalised twice per week on Mondays and Thursdays starting 20221219 and ending 20230320. For each start date, three ensemble forecasts are run, representing initialisations in current, pre-industrial and future climate states. These are split between six MARS experiment versions as follows: - Initialised Dec 2022 - Jan 2023 - current = b2r0 - pre-industrial = b2r1 - future = b2r2 - Initialised Feb 2023 - Mar 2023 - current = b2r7 - pre-industrial = b2r8 - future = b2r9 We acknowledge the use of ECMWF's computing and archive facilities in this research under the special project spgbleac, without which this work would not have been possible. If you are interested in using these data, please let us know by contacting nicholas.leach@physics.ox.ac.uk .
DOI 10.21957/5rse-e053
Experiment ID b2r7
Experiment class United Kingdom
Examples

This requests the 50 perturbed members of total vertically-integrated column water vapour over the Pacific Ocean for a present-day "operational" forecast initialised on the 2nd February 2023 in netCDF format.

#!/usr/bin/env python
from ecmwfapi import ECMWFDataServer

server = ECMWFDataServer()

server.retrieve({
    "area": "60/100/0/300",
    "class": "uk",
    "dataset": "research",
    "date": "2023-02-02",
    "expver": "b2r7",
    "format": "netcdf",
    "grid": "0.25/0.25",
    "levtype": "sfc",
    "number": "1/2/3/4/5/6/7/8/9/10/11/12/13/14/15/16/17/18/19/20/21/22/23/24/25/26/27/28/29/30/31/32/33/34/35/36/37/38/39/40/41/42/43/44/45/46/47/48/49/50",
    "param": "137.128",
    "step": "0/3/6/9/12/15/18/21/24/27/30/33/36/39/42/45/48/51/54/57/60/63/66/69/72/75/78/81/84/87/90/93/96/99/102/105/108/111/114/117/120/123/126/129/132/135/138/141/144/147/150/153/156/159/162/165/168/171/174/177/180/183/186/189/192/195/198/201/204/207/210/213/216/219/222/225/228/231/234/237/240/243/246/249/252/255/258/261/264/267/270/273/276/279/282/285/288/291/294/297/300/303/306/309/312/315/318/321/324/327/330/333/336",
    "stream": "enfo",
    "target": "pacific_pf_tcwv_20230202.nc",
    "time": "00:00:00",
    "type": "pf"
})