Data for: Unravelling the spatial and temporal variability of natural disturbances in European forests
Abstract
Despite disturbances intensifying across European forests, it is not well known how their baseline regimes and trends vary across regions and disturbance agents. Here, we assessed the main disturbance regimes in European forests based on their mean size, severity, and frequency for (i) fires and (ii) wind and bark beetle disturbances, as well as their spatiotemporal variability. We used the European Forest Disturbance Atlas (Viana et al. 2025) to characterise 3,825,259 disturbance events that occurred in European forests between 1985 and 2023. Using Gaussian finite mixture models, we identified the dominant disturbance clusters (i.e., disturbance regimes) for the two agent groups and quantified the spatial variability of disturbances both between and within biomes (boreal, temperate, Mediterranean). Finally, we compared changes in disturbance clusters over time by splitting the study period into three intervals and assessing cluster shifts from the first to the third period (1985–1997 and 2011–2023), as well as annual trends from 1985 to 2023. We found that fire regimes exhibited a marked north–south latitudinal gradient: severe and rare fires occurred in boreal and temperate biomes, whereas moderate, and large and frequent fires predominated initerr,anean and temperate–Mediterranean transitional forests. For wind and bark beetle disturbances, we identified four distinct regimes: moderate disturbances predominated in boreal and temperate biomes; mild and rare disturbances occurred in Mediterranean and temperate–Mediterranean forests; and frequent and small, as well as severe and large disturbances, predominated in Central Europe and the British Isles, respectively. Approximately 15% of all grid cells shifted to a different disturbance regime during the study period. Fire frequency and severity declined in temperate and Mediterranean forests between the first and second periods (1985–1997 and 1998–2010). Wind and bark beetle disturbances decreased in size in boreal and temperate forests during the same interval, followed by increases in disturbance severity in temperate forests between the second and third periods (1998–2010 and 2011–2023).
The repository contains two main folders: lib and data.
- lib.zip
This folder contains the R scripts (developed in R version 4.3.1) used to generate the analyses and figures presented in the study. It includes the following files:
- 00_functions_jae.R – Contains all custom functions developed for the study. These functions are automatically sourced in scripts 03 to 05.
- 00_variables_jae.R – Defines all variables required to run scripts 04 and 05. This file is automatically sourced within those scripts.
- 01_create_grids.R – Creates hexagonal grids at user-specified spatial scales across Europe. These grids are subsequently used as spatial units for summarising disturbance information.
- 02_calculate_patch_metrics.R – Loads disturbance data from the European Forest Disturbance Atlas (Viana-Soto and Senf, 2025), aggregates pixel-based to patch-based disturbances,
computes multiple disturbance metrics, and extracts information on the disturbance agent, year, and grid ID. - 03_summarise_regimes.R – Summarises disturbance patch data (from script 02) by disturbance agent, grid ID, year, and study period.
- 04_regime_clustering.R – Performs principal component analyses (PCA) and Gaussian finite mixture models for fire-, wind-, and bark beetle–related disturbances, and generates the corresponding data frames and plots.
- 05_create_additional_figures.R – Conducts Wilcoxon tests on disturbance regime clusters (from script 04), computes temporal trends, and produces additional figures.
- data.zip
This folder contains the processed datasets used in the analyses. RDS files can be loaded in R using the readRDS() function.
- all_patch_data_50km.rds – Contains patch-level information (e.g., severity and area of the disturbance) for all disturbance events from the European Forest Disturbance Atlas (Viana-Soto and Senf, 2025),
and results from script 02_calculate_patch_metrics.R. - regime_3_period_50km.rds – Summarised version of all_patch_data_50km.rds, aggregated into two data frames: (1) by disturbance agent, grid ID, and year,r and (2) by disturbance agent, grid ID and period.
- grids_europe_50km.shp – Shapefile containing the 50 km hexagonal grid cells of Europe created with 01_create_grids.R. These grids were used as spatial units for summarising disturbances and characterising
disturbance regime clusters in scripts 03 to 05.