Global environmental controls of wildfire burnt area, size and intensity.
File(s)Haas_2022_Environ._Res._Lett._17_065004 (1).pdf (10.72 MB)
Published version
Author(s)
Haas, Olivia
Prentice, Iain Colin
Harrison, Sandy P
Type
Journal Article
Abstract
Fire is an important influence on the global patterns of vegetation structure and composition. Wildfire is included as a distinct process in many dynamic global vegetation models but limited current understanding of fire regimes restricts these models' ability to reproduce more than the broadest geographic patterns. Here we present a statistical analysis of the global controls of remotely sensed burnt area (BA), fire size (FS), and a derived metric related to fire intensity (FI). Separate generalized linear models were fitted to observed monthly fractional BA from the Global Fire Emissions Database (GFEDv4), median FS from the Global Fire Atlas, and median fire radiative power from the MCD14ML dataset normalized by the square root of median FS. The three models were initially constructed from a common set of 16 predictors; only the strongest predictors for each model were retained in the final models. It is shown that BA is primarily driven by fuel availability and dryness; FS by conditions promoting fire spread; and FI by fractional tree cover and road density. Both BA and FS are constrained by landscape fragmentation, whereas FI is constrained by fuel moisture. Ignition sources (lightning and human population) were positively related to BA (after accounting for road density), but negatively to FI. These findings imply that the different controls on BA, FS and FI need to be considered in process-based models. They highlight the need to include measures of landscape fragmentation as well as fuel load and dryness, and to pay close attention to the controls of fire spread.
Date Issued
2022-05-13
Date Acceptance
2022-04-26
Citation
Environmental Research Letters, 2022, 17 (6), pp.1-12
ISSN
1748-9326
Publisher
Institute of Physics (IoP)
Start Page
1
End Page
12
Journal / Book Title
Environmental Research Letters
Volume
17
Issue
6
Copyright Statement
© 2022 The Author(s). Published by IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
License URL
Sponsor
Commission of the European Communities
Leverhulme Trust
The Leverhulme Trust
The Eric & Wendy Schmidt Fund for Strategic Innovation
Identifier
https://iopscience.iop.org/article/10.1088/1748-9326/ac6a69
Grant Number
787203
RC-2018-023
PO:3300774 (1005109-LEMONTREE)
Subjects
Meteorology & Atmospheric Sciences
Publication Status
Published
Date Publish Online
2022-05-13