BC Wildfire PSTA Lightning Fire Density

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Published by the Ministry of Forests, Lands, Natural Resource Operations and Rural Development - BC Wildfire Service
Licensed under Access Only

Provincial Strategic Threat Analysis (PSTA) is designed to consistently assess and map potential wildfire threats to values across the landscape (including communities, infrastructure and natural resources) and to integrate different aspects of wildfire hazard and risk.

The lightning caused fire density layer was analyzed using lightning caused fires with final sizes greater than 4.0 ha for the last 67 years (1950-2016). These were given a weight of one (1) in the analysis, while large fires (> 500 ha) were given a weight of 5, in order to reflect the much greater cost and damage usually associated with larger fires. A kernel density analysis was conducted to represent the historic fire data as a seamless surface representing fire occurrence across the province; a 10 km search radius was chosen, and the pixel size was 50 m. The ArcGIS kernel density function fits a smooth surface to a spatial point frequency dataset, representing actual fire origin points as random samples from a smooth probability surface. The analysis search radius was 10 kilometers and this distance was reflected in the mapped output classes; thus, the fire density at any point on the landscape is a modeled probability value reflecting the number of historic fires found within a radius of 10 kilometers, or within a 314 km2 circle around the point of interest. Note that this is different from a simple point density, and the values in the fire density layer classes do not represent the exact numbers of historic fires within the search radius; closer and more clustered fires are weighted higher within that circle, and this can result in significantly higher values than may be expected compared with a simple point search.The output values therefore represent a modeled probability approximately representing the number of nearby fires (4 ha and greater, treating 500+ ha fires as 5 individual events) since 1950. Using this as an input to the Wildfire Threat Analysis layer is based on the premise that areas that were prone to multiple larger fires in the past are likely prone to larger fires in the present and near future. Final class limits are based on the weighting scheme described above: fires from 0 to 4 ha (not counted, weight of 0); fires from 4.001 to 500 ha (weight of 1); fires 500.001 ha or larger (weight of 5). Units are approximate weighted fire frequency within a 10 km radius, 1950-2016. Water bodies were overlaid on the raster and assigned their own class, -1.

Data and Resources

Dataset Extent

Latitude: 48.0° to 60.0°
Longitude: -139.5° to -113.5°

Additional Information

Contact Information

NameDevona Hay (pointOfContact)
EmailBCWILDFIREGEO@gov.bc.ca
OrganizationMinistry of Forests, Lands, Natural Resource Operations and Rural Development
Sub-OrganizationBC Wildfire Service
NameDana Hicks (businessExpert)
EmailDana.Hicks@gov.bc.ca
OrganizationMinistry of Forests, Lands, Natural Resource Operations and Rural Development
Sub-OrganizationBC Wildfire Service

Access & Security

Who can view this dataset? Public
Who can download this dataset?Public

Metadata Information

Record Published 2020-02-05
Record Last Modified 2020-02-18
Resource Status underDevelopment
Spatial DataSDO_GEOMETRY

Object Description

Object Name: WHSE_LAND_AND_NATURAL_RESOURCE.PROT_PSTA_LTG_FIRE_ST_DNSTY_SP

Short Name: PROTPSTALT
Comments: Provincial Strategic Threat Analysis (PSTA) lightning fire density is a modeled probability approximately representing the number of nearby lightning caused fires (4 ha and greater, treating 500+ ha fires as 5 individual events) since 1950.

Column Name Short Name Data Type Data Precision Comments
PROT_PLFSD_SYSID PRT_PLFSDD NUMBER 10 PROT_PLFSD_SYSID is a system generated unique identification number.
GRIDCODE GRIDCODE NUMBER 2 The output values represent a modeled probability approximately representing the number of nearby fires (4 ha and greater, treating 500+ ha fires as 5 individual events) since 1950. Values range from 1 to 6 with 1 being lowest probability. There is also a value of -1 which denotes water.
FIRE_START_DENSITY FR_STRT_DY VARCHAR2 30 Textual range description of the modeled probability for fire starts, e.g., 1 - 5 (Lowest Density), 10.1 - 17, 17.1 - 24, 24.1 - 33, ... , > 116 (Highest Density), No Fires, Water.
FEATURE_AREA_SQM FEAT_AREA NUMBER 19 FEATURE_AREA_SQM is the system calculated area of a two-dimensional polygon in square meters.
FEATURE_LENGTH_M FEAT_LEN NUMBER 19 FEATURE_LENGTH_M is the system calculated length or perimeter of a geometry in meters.
SHAPE SHAPE SDO_GEOMETRY 1 SHAPE is the column used to reference the spatial coordinates defining the feature.
OBJECTID OBJECTID NUMBER 38 OBJECTID is a column required by spatial layers that interact with ESRI ArcSDE. It is populated with unique values automatically by SDE.
SE_ANNO_CAD_DATA BLOB 4000 SE_ANNO_CAD_DATA is a binary column used by spatial tools to store annotation, curve features and CAD data when using the SDO_GEOMETRY storage data type.