Global Daily FFDI Projections from HadCM3C Perturbed Physics Ensemble - RCP8.5

This dataset contains daily McArthur Forest Fire Danger Index (FFDI) outputs derived from the HadCM3C Perturbed Physics Ensemble (PPE) under two future emissions scenarios. Data is split between two report, the RCP2.6 Data Repository here, while this one is the RCP8.5 Data Repository here.

Each repository includes NetCDF files (.nc.gz) representing daily FFDI values for 57 ensemble members. The data spans from 1 January 1970 to 22 December 2097 on a global 3.75° x 2.5° grid using the following projection: +proj=longlat +R=6371229

File Naming Convention

NetCDF files that contain daily FFDI values follow the structure: ffdi_joined_rcpX.x_XXXXX.nc.gz

Where:

rcpX.x refers to the emissions scenario (2.6 or 8.5).

XXXXX represents the unique ensemble member ID.

We also include three files that, for each ensemble member (first column), contain the start (2nd column) and end date (3rd column) of the 20-year running mean of the exceedance window of 1.5, 2 and 4°C global warming level. These filenames have the structure  rcpX_xgwl_Y_y.txt Where:

rcpXyx refers to the emissions scenario (2.6 or 8.5).

Y_y represents the global warming level above pre-industrial

Dataset Overview

Variables: Daily FFDI values calculated from model outputs of temperature, relative humidity, wind speed, and precipitation.

Temporal Coverage: 1970-01-01 to 2097-12-22.

Spatial Coverage: Global grid at 3.75° longitude x 2.5° latitude resolution.

Number of Ensemble Members: 57.

Methodology

The FFDI was computed using input variables from the HadCM3C PPE, which incorporates dynamic vegetation and carbon cycle feedbacks. This ensemble samples uncertainties in atmospheric feedbacks, land carbon processes, and ocean physics. The FFDI is calculated as:

FFDI = 1.25 * DF * exp[((T - H) / 30.0) + 0.0234 * V]

Where:

T = daily maximum temperature at 1.5m (°C),

H = daily relative humidity (%),

V = daily wind speed at 10m (km/h),

DF = drought factor, derived from soil moisture deficit and recent precipitation.

For a detailed explanation of the methodology and the specific parameters used, refer to our associated publication once published:DOI: xxxxx

Usage Notes

Data Formats: Files are compressed NetCDF (.nc.gz) and can be accessed using tools like Python's xarray, R's ncdf4, or command-line tools like ncdump.

Applications: This data is suitable for assessing future changes in fire weather conditions, global fire risk analysis, and climate impact assessments.

Citation

If you use this dataset, please cite:

Taylor et al. (2024). Limiting global warming to 1.5°C minimises projected global increases in fire weather days, but adaptation to new fire regimes is still needed. . DOI: xxxxx