Global expansion of wildland-urban interface (WUI) and WUI fires: insights from a multiyear worldwide unified database (WUWUI)

Fires in the wildland-urban interface (WUI) are an important issue globally. To understand the change of WUI, we develop a 9 km worldwide unified wildland-urban interface database for 2001–2020 with Random Forest models and satellite data. We find that WUI has been increasing in all populated contin...

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Main Authors: Wenfu Tang, Cenlin He, Louisa Emmons, Junzhe Zhang
Format: Article
Language:English
Published: IOP Publishing 2024-01-01
Series:Environmental Research Letters
Subjects:
Online Access:https://doi.org/10.1088/1748-9326/ad31da
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author Wenfu Tang
Cenlin He
Louisa Emmons
Junzhe Zhang
author_facet Wenfu Tang
Cenlin He
Louisa Emmons
Junzhe Zhang
author_sort Wenfu Tang
collection DOAJ
description Fires in the wildland-urban interface (WUI) are an important issue globally. To understand the change of WUI, we develop a 9 km worldwide unified wildland-urban interface database for 2001–2020 with Random Forest models and satellite data. We find that WUI has been increasing in all populated continents from 2001 to 2020 and the global relative increase is 24%, with the largest relative increase (∼59%) over Africa. Global total fire counts decrease by 10% from 2005 to 2020, whereas the WUI fraction of fire counts increases by 23%. The global total burned area decreases by 22% from 2005 to 2020, whereas the WUI fraction of burned area increases by 35%. These are mainly due to the expansion of WUI area. On all the populated continents, the WUI fractions of fire counts are higher than the WUI fractions of burned area, implying that WUI fires tend to have smaller sizes than wildland fires. We also project future WUI changes for the years 2030 and 2040, together with the projection of future fire burned area under different shared socioeconomic pathways (SSP) scenarios in the Community Earth System Model version 2 (CESM2). The projected global WUI fraction (excluding Antarctica and the oceans) is 5.9% in 2040 compared to 4.8% in 2020. The global WUI fraction of burned area is projected to increase from now to 2040 under most scenarios analyzed in this study, unless the WUI area stays at the 2020 level together with the projected burned area under SSP4-4.5. This study is a first step to understanding the changes of WUI fires at the global scale and demonstrates a growing importance of WUI fires. The global multi-year WUI and WUI fire datasets developed in this study can facilitate future work quantifying the impacts of WUI fires on air quality and climate.
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spelling doaj.art-40573a8b91264683896934a8dd70cdac2024-03-19T17:39:55ZengIOP PublishingEnvironmental Research Letters1748-93262024-01-0119404402810.1088/1748-9326/ad31daGlobal expansion of wildland-urban interface (WUI) and WUI fires: insights from a multiyear worldwide unified database (WUWUI)Wenfu Tang0https://orcid.org/0000-0002-0107-4496Cenlin He1https://orcid.org/0000-0002-7367-2815Louisa Emmons2https://orcid.org/0000-0003-2325-6212Junzhe Zhang3https://orcid.org/0000-0003-0215-7514Atmospheric Chemistry Observations & Modeling Laboratory, NSF National Center for Atmospheric Research , Boulder, CO, United States of AmericaResearch Applications Laboratory, NSF National Center for Atmospheric Research , Boulder, CO, United States of AmericaAtmospheric Chemistry Observations & Modeling Laboratory, NSF National Center for Atmospheric Research , Boulder, CO, United States of AmericaDepartment of Geography, University of California , Los Angeles, CA 90095, United States of AmericaFires in the wildland-urban interface (WUI) are an important issue globally. To understand the change of WUI, we develop a 9 km worldwide unified wildland-urban interface database for 2001–2020 with Random Forest models and satellite data. We find that WUI has been increasing in all populated continents from 2001 to 2020 and the global relative increase is 24%, with the largest relative increase (∼59%) over Africa. Global total fire counts decrease by 10% from 2005 to 2020, whereas the WUI fraction of fire counts increases by 23%. The global total burned area decreases by 22% from 2005 to 2020, whereas the WUI fraction of burned area increases by 35%. These are mainly due to the expansion of WUI area. On all the populated continents, the WUI fractions of fire counts are higher than the WUI fractions of burned area, implying that WUI fires tend to have smaller sizes than wildland fires. We also project future WUI changes for the years 2030 and 2040, together with the projection of future fire burned area under different shared socioeconomic pathways (SSP) scenarios in the Community Earth System Model version 2 (CESM2). The projected global WUI fraction (excluding Antarctica and the oceans) is 5.9% in 2040 compared to 4.8% in 2020. The global WUI fraction of burned area is projected to increase from now to 2040 under most scenarios analyzed in this study, unless the WUI area stays at the 2020 level together with the projected burned area under SSP4-4.5. This study is a first step to understanding the changes of WUI fires at the global scale and demonstrates a growing importance of WUI fires. The global multi-year WUI and WUI fire datasets developed in this study can facilitate future work quantifying the impacts of WUI fires on air quality and climate.https://doi.org/10.1088/1748-9326/ad31dawildland-urban interfacefireburned areafuture projectionMODISfire counts
spellingShingle Wenfu Tang
Cenlin He
Louisa Emmons
Junzhe Zhang
Global expansion of wildland-urban interface (WUI) and WUI fires: insights from a multiyear worldwide unified database (WUWUI)
Environmental Research Letters
wildland-urban interface
fire
burned area
future projection
MODIS
fire counts
title Global expansion of wildland-urban interface (WUI) and WUI fires: insights from a multiyear worldwide unified database (WUWUI)
title_full Global expansion of wildland-urban interface (WUI) and WUI fires: insights from a multiyear worldwide unified database (WUWUI)
title_fullStr Global expansion of wildland-urban interface (WUI) and WUI fires: insights from a multiyear worldwide unified database (WUWUI)
title_full_unstemmed Global expansion of wildland-urban interface (WUI) and WUI fires: insights from a multiyear worldwide unified database (WUWUI)
title_short Global expansion of wildland-urban interface (WUI) and WUI fires: insights from a multiyear worldwide unified database (WUWUI)
title_sort global expansion of wildland urban interface wui and wui fires insights from a multiyear worldwide unified database wuwui
topic wildland-urban interface
fire
burned area
future projection
MODIS
fire counts
url https://doi.org/10.1088/1748-9326/ad31da
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