Heat-related urban mortality attributable to human-induced climate change in Europe in summer 2026

Notebook and temperature data to replicate the attribution analysis used in Barnes et al. (2026), ''Heat-related urban mortality attributable to human-induced climate change in Europe in summer 2026'':

betas-and-counterfactuals.ipynb is a Jupyter notebook providing R code used to estimate and synthesise the beta parameters (local warming as a function of GMST) for 854 European cities, and generate counterfactual temperatures for the summer months of 2026.

Attribution results:

beta-pars_full-synthesis.rds is an RDS file containing central estimates and quantiles of the beta parameters from all data sources, including synthesised values.

beta-pars_sample-from-unweighted.rds is an RDS file containing the spatiotemporally coherent sample of the synthesised beta parameters used to derive the counterfactual temperatures.

Factual time series:

ts-factual_era5-land_20260501-20260831.csv contains factual time series (summer daily mean temperatures from May 1st - August 31st) for the 854 cities.

Files used in attribution analysis:

gmst.txt contains the 4-year smoothed GMST covariate series used to estimate the beta parameters for observations-based datasets.

t2m-monthly_*.csv are monthly temperature series from observational data products used to estimate the beta parameters.

cmip6.zip contains all temperature series and smoothed GMST series used to estimate the beta parameters for the CMIP6 models.

Supporting information:

cities.csv matches the Urban Audit city codes with city names, 2026 population estimates from WorldPop and coordinates used to generate the maps.