Spatial patterns and controls on burned area for two contrasting fire regimes in Southern California

Humans influence the frequency and spatial pattern of fire and contribute to altered fire regimes, but fuel loading is often the only factor considered when planning management activities to reduce fire hazard. Understanding both the human and biophysical landscape characteristics that explain how fire patterns vary should help to identify where fire is most likely to threaten values at risk. We used human and biophysical explanatory variables to model and map the spatial patterns of both fire ignitions and fire frequency in the Santa Monica Mountains, a human-dominated southern California landscape. Most fires in the study area are caused by humans, and our results showed that fire ignition patterns were strongly influenced by human variables. In particular, ignitions were most likely to occur close to roads, trails, and housing development but were also related to vegetation type. In contrast, biophysical variables related to climate and terrain (January temperature, transformed aspect, elevation, and slope) explained most of the variation in fire frequency. Although most ignitions occur close to human infrastructure, fires were more likely to spread when located farther from urban development. How far fires spread was ultimately related to biophysical variables, and the largest fires in southern California occurred as a function of wind speed, topography, and vegetation type. Overlaying predictive maps of fire ignitions and fire frequency may be useful for identifying high-risk areas that can be targeted for fire management actions.

Download Full-text

Response of simulated burned area to historical changes in environmental and anthropogenic factors: a comparison of seven fire models

Biogeosciences ◽

10.5194/bg-16-3883-2019 ◽

2019 ◽

Vol 16 (19) ◽

pp. 3883-3910 ◽

Cited By ~ 5

Author(s):

Lina Teckentrup ◽

Sandy P. Harrison ◽

Stijn Hantson ◽

Angelika Heil ◽

Joe R. Melton ◽

...

Keyword(s):

Land Use ◽

Co2 Concentration ◽

Fire Regimes ◽

Atmospheric Co2 ◽

Anthropogenic Factors ◽

Burned Area ◽

Earth System ◽

Atmospheric Co2 Concentration ◽

Fire Models ◽

The Impact

Abstract. Understanding how fire regimes change over time is of major importance for understanding their future impact on the Earth system, including society. Large differences in simulated burned area between fire models show that there is substantial uncertainty associated with modelling global change impacts on fire regimes. We draw here on sensitivity simulations made by seven global dynamic vegetation models participating in the Fire Model Intercomparison Project (FireMIP) to understand how differences in models translate into differences in fire regime projections. The sensitivity experiments isolate the impact of the individual drivers on simulated burned area, which are prescribed in the simulations. Specifically these drivers are atmospheric CO2 concentration, population density, land-use change, lightning and climate. The seven models capture spatial patterns in burned area. However, they show considerable differences in the burned area trends since 1921. We analyse the trajectories of differences between the sensitivity and reference simulation to improve our understanding of what drives the global trends in burned area. Where it is possible, we link the inter-model differences to model assumptions. Overall, these analyses reveal that the largest uncertainties in simulating global historical burned area are related to the representation of anthropogenic ignitions and suppression and effects of land use on vegetation and fire. In line with previous studies this highlights the need to improve our understanding and model representation of the relationship between human activities and fire to improve our abilities to model fire within Earth system model applications. Only two models show a strong response to atmospheric CO2 concentration. The effects of changes in atmospheric CO2 concentration on fire are complex and quantitative information of how fuel loads and how flammability changes due to this factor is missing. The response to lightning on global scale is low. The response of burned area to climate is spatially heterogeneous and has a strong inter-annual variation. Climate is therefore likely more important than the other factors for short-term variations and extremes in burned area. This study provides a basis to understand the uncertainties in global fire modelling. Both improvements in process understanding and observational constraints reduce uncertainties in modelling burned area trends.

Download Full-text

Biomass burning fuel consumption dynamics in the tropics and subtropics assessed from satellite

Biogeosciences ◽

10.5194/bg-13-3717-2016 ◽

2016 ◽

Vol 13 (12) ◽

pp. 3717-3734 ◽

Cited By ~ 22

Author(s):

Niels Andela ◽

Guido R. van der Werf ◽

Johannes W. Kaiser ◽

Thijs T. van Leeuwen ◽

Martin J. Wooster ◽

...

Keyword(s):

South America ◽

Fuel Consumption ◽

Spatial Patterns ◽

Field Measurements ◽

Sub Saharan Africa ◽

Burned Area ◽

Return Periods ◽

Sub Saharan ◽

In Fire ◽

Consumption Dynamics

Abstract. Landscape fires occur on a large scale in (sub)tropical savannas and grasslands, affecting ecosystem dynamics, regional air quality and concentrations of atmospheric trace gasses. Fuel consumption per unit of area burned is an important but poorly constrained parameter in fire emission modelling. We combined satellite-derived burned area with fire radiative power (FRP) data to derive fuel consumption estimates for land cover types with low tree cover in South America, Sub-Saharan Africa, and Australia. We developed a new approach to estimate fuel consumption, based on FRP data from the polar-orbiting Moderate Resolution Imaging Spectroradiometer (MODIS) and the geostationary Spinning Enhanced Visible and Infrared Imager (SEVIRI) in combination with MODIS burned-area estimates. The fuel consumption estimates based on the geostationary and polar-orbiting instruments showed good agreement in terms of spatial patterns. We used field measurements of fuel consumption to constrain our results, but the large variation in fuel consumption in both space and time complicated this comparison and absolute fuel consumption estimates remained more uncertain. Spatial patterns in fuel consumption could be partly explained by vegetation productivity and fire return periods. In South America, most fires occurred in savannas with relatively long fire return periods, resulting in comparatively high fuel consumption as opposed to the more frequently burning savannas in Sub-Saharan Africa. Strikingly, we found the infrequently burning interior of Australia to have higher fuel consumption than the more productive but frequently burning savannas in northern Australia. Vegetation type also played an important role in explaining the distribution of fuel consumption, by affecting both fuel build-up rates and fire return periods. Hummock grasslands, which were responsible for a large share of Australian biomass burning, showed larger fuel build-up rates than equally productive grasslands in Africa, although this effect might have been partially driven by the presence of grazers in Africa or differences in landscape management. Finally, land management in the form of deforestation and agriculture also considerably affected fuel consumption regionally. We conclude that combining FRP and burned-area estimates, calibrated against field measurements, is a promising approach in deriving quantitative estimates of fuel consumption. Satellite-derived fuel consumption estimates may both challenge our current understanding of spatiotemporal fuel consumption dynamics and serve as reference datasets to improve biogeochemical modelling approaches. Future field studies especially designed to validate satellite-based products, or airborne remote sensing, may further improve confidence in the absolute fuel consumption estimates which are quickly becoming the weakest link in fire emission estimates.

Download Full-text

Altered Fire Regimes Affect Landscape Patterns of Plant Succession in the Foothills and Mountains of Southern California

Ecosystems ◽

10.1007/s10021-005-0017-6 ◽

2005 ◽

Vol 8 (8) ◽

pp. 885-898 ◽

Cited By ~ 45

Author(s):

Janet Franklin ◽

Alexandra D. Syphard ◽

Hong S. He ◽

David J. Mladenoff

Keyword(s):

Southern California ◽

Fire Regimes ◽

Landscape Patterns ◽

Plant Succession

Download Full-text

Utility and optimization of LANDSAT-derived burned area maps for southern California

International Journal of Remote Sensing ◽

10.1080/01431161.2020.1809741 ◽

2020 ◽

Vol 42 (2) ◽

pp. 486-505

Author(s):

Emanuel Arnal Storey ◽

Krista R. Lee West ◽

Douglas A. Stow

Keyword(s):

Southern California ◽

Burned Area

Download Full-text

SPATIAL PATTERNS AND CONTROLS ON HISTORICAL FIRE REGIMES AND FOREST STRUCTURE IN THE KLAMATH MOUNTAINS

Ecological Applications ◽

10.1890/1051-0761(2003)013[0704:spacoh]2.0.co;2 ◽

2003 ◽

Vol 13 (3) ◽

pp. 704-719 ◽

Cited By ~ 216

Author(s):

Alan H. Taylor ◽

Carl N. Skinner

Keyword(s):

Spatial Patterns ◽

Forest Structure ◽

Fire Regimes ◽

Klamath Mountains

Download Full-text

Fire spread from MODIS burned area data: obtaining fire dynamics information for every single fire

International Journal of Wildland Fire ◽

10.1071/wf16003 ◽

2016 ◽

Vol 25 (12) ◽

pp. 1228 ◽

Cited By ~ 8

Author(s):

David Frantz ◽

Marion Stellmes ◽

Achim Röder ◽

Joachim Hill

Keyword(s):

Large Scale ◽

Fire Regimes ◽

Fire Spread ◽

Burned Area ◽

Large Area ◽

Fire Dynamics ◽

Seed Point ◽

Individual Object ◽

The Individual ◽

Area Data

Fire spread information on a large scale is still a missing key layer for a complete description of fire regimes. We developed a novel multilevel object-based methodology that extracts valuable information about fire dynamics from Moderate Resolution Imaging Spectroradiometer (MODIS) burned area data. Besides the large area capabilities, this approach also derives very detailed information for every single fire regarding timing and location of its ignition, as well as detailed directional multitemporal spread information. The approach is a top–down approach and a multilevel segmentation strategy is used to gradually refine the individual object membership. The multitemporal segmentation alternates between recursive seed point identification and queue-based fire tracking. The algorithm relies on only a few input parameters that control the segmentation with spatial and temporal distance thresholds. We present exemplary results that indicate the potential for further use of the derived parameters.

Download Full-text

Biomass burning fuel consumption dynamics in the (sub)tropics assessed from satellite

10.5194/bg-2015-582 ◽

2016 ◽

Cited By ~ 1

Author(s):

N. Andela ◽

G. R. van der Werf ◽

J. W. Kaiser ◽

T. T. van Leeuwen ◽

M. J. Wooster ◽

...

Keyword(s):

South America ◽

Fuel Consumption ◽

Spatial Patterns ◽

Biomass Burning ◽

Field Measurements ◽

Sub Saharan Africa ◽

Burned Area ◽

Return Periods ◽

In Fire ◽

Consumption Dynamics

Abstract. Landscape fires occur on a large scale in (sub)tropical savannas and grasslands, affecting ecosystem dynamics, regional air quality and concentrations of atmospheric trace gasses. Fuel consumption per unit of area burned is an important but poorly constrained parameter in fire emission modelling. We combined satellite-derived burned area with fire radiative power (FRP) data to derive fuel consumption estimates for land cover types with low tree cover in South America, SubSaharan Africa, and Australia. We developed a new approach to estimate fuel consumption, based on FRP data from the polar orbiting MODerate-resolution Imaging Spectroradiometer (MODIS) and the geostationary Spinning Enhanced Visible and Infrared Imager (SEVIRI) in combination with MODIS burned area estimates. The fuel consumption estimates based on the geostationary and polar orbiting instruments showed good agreement in terms of spatial patterns, but absolute fuel consumption estimates remained more uncertain. Fuel consumption varies considerably in space and time, complicating the comparison of various approaches and using field measurements to constrain our results. Spatial patterns in fuel consumption could be partly explained by vegetation productivity and fire return periods. In South America, most fires occurred in savannas with relatively long fire return periods, resulting in comparatively high fuel consumption as opposed to the more frequently burning savannas in Sub-Saharan Africa. Strikingly, we found the infrequently burning interior of Australia having higher fuel consumption than the more productive but frequently burning savannas in northern Australia. Vegetation type also played an important role in explaining the distribution of fuel consumption, both by affecting fuel build up rates and fire return periods. Hummock grasslands, which were responsible for a large share of Australian biomass burning, showed larger fuel build up rates than equally productive grasslands in Africa, although this effect might have been partially driven by the presence of grazers in Africa. Finally, land management in the form of deforestation and agriculture also considerably affected fuel consumption regionally. We conclude that combining FRP and burned area estimates, calibrated against field measurements, is a promising approach in deriving quantitative estimates of fuel consumption. Satellite derived fuel consumption estimates may both challenge our current understanding of spatiotemporal fuel consumption dynamics and serve as reference datasets to improve biogeochemical modelling approaches. Future field studies especially designed to validate satellite-based products, or airborne remote sensing, may further improve confidence in the absolute fuel consumption estimates which are quickly becoming the weakest link in fire emissions estimates.

Download Full-text

The reconstruction of burned area and fire severity using charcoal from boreal lake sediments

The Holocene ◽

10.1177/0959683620932979 ◽

2020 ◽

Vol 30 (10) ◽

pp. 1400-1409 ◽

Cited By ~ 1

Author(s):

Andy Hennebelle ◽

Julie C Aleman ◽

Adam A Ali ◽

Yves Bergeron ◽

Christopher Carcaillet ◽

...

Keyword(s):

Lake Sediments ◽

Surface Area ◽

Fire Severity ◽

Source Area ◽

Fire Regimes ◽

Burned Area ◽

Median Surface ◽

Landsat Images ◽

Eastern Canada ◽

Lag Effects

Although lacustrine sedimentary charcoal has long been used to infer paleofires, their quantitative reconstructions require improvements of the calibration of their links with fire regimes (i.e. occurrence, area, and severity) and the taphonomic processes that affect charcoal particles between the production and the deposition in lake sediments. Charcoal particles >150 µm were monitored yearly from 2011 to 2016 using traps submerged in seven head lakes situated in flat-to-rolling boreal forest landscapes in eastern Canada. The burned area was measured, and the above-ground fire severity was assessed using the differentiated normalized burn ratio (dNBR) index, derived from LANDSAT images, and measurements taken within zones radiating 3, 15, and 30 km from the lakes. In order to evaluate potential lag effects in the charcoal record, fire metrics were assessed for the year of recorded charcoal recording (lag 0) and up to 5 years before charcoal deposition (lag 5). A total of 92 variables were generated and sorted using a Random Forest-based methodology. The most explanatory variables for annual charcoal particle presence, expressed as the median surface area, were selected. Results show that, temporally, sedimentary charcoal accurately recorded fire events without a temporal lag; spatially, fires were recorded up to 30 km from the lakes. Selected variables highlighted the importance of burned area and fire severity in explaining lacustrine charcoal. The charcoal influx was thus driven by fire area and severity during the production process. The dispersion process of particles resulted mostly of wind transportation within the regional (<30 km) source area. Overall, charcoal median surface area represents a reliable proxy for reconstructing past burned areas and fire severities.

Download Full-text

Inter- and intra-annual profiles of fire regimes in the managed forests of Canada and implications for resource sharing

International Journal of Wildland Fire ◽

10.1071/wf11026 ◽

2012 ◽

Vol 21 (4) ◽

pp. 328 ◽

Cited By ~ 9

Author(s):

Steen Magnussen ◽

Stephen W. Taylor

Keyword(s):

Resource Sharing ◽

Joint Distribution ◽

Fire Management ◽

Fire Regime ◽

Fire Regimes ◽

Fire Season ◽

Burned Area ◽

Fire Activity ◽

In Fire ◽

Regional Synchrony

Year-to-year variation in fire activity in Canada constitutes a key challenge for fire management agencies. Interagency sharing of fire management resources has been ongoing on regional, national and international scales in Canada for several decades to better cope with peaks in resource demand. Inherent stressors on these schemes determined by the fire regimes in constituent jurisdictions are not well known, nor described by averages. We developed a statistical framework to examine the likelihood of regional synchrony of peaks in fire activity at a timescale of 1 week. Year-to-year variations in important fire regime variables and 48 regions in Canada are quantified by a joint distribution and profiled at the Provincial or Territorial level. The fire regime variables capture the timing of the fire season, the average number of fires, area burned, and the timing and extent of annual maxima. The onset of the fire season was strongly correlated with latitude and longitude. Regional synchrony in the timing of the maximum burned area within fire seasons delineates opportunities for and limitations to sharing of fire suppression resources during periods of stress that were quantified in Monte Carlo simulations from the joint distribution.

Download Full-text