Low Income Population Concentration - Southern CA

Relative concentration of the estimated number of people in the Southern California region that live in a household defined as "low income." There are multiple ways to define low income. These data apply the most common standard: low income population consists of all members of households that collectively have income less than twice the federal poverty threshold that applies to their household type. Household type refers to the household's resident composition: the number of independent adults plus dependents that can be of any age, from children to elderly. For example, a household with four people '€“ one working adult parent and three dependent children '€“ has a different poverty threshold than a household comprised of four unrelated independent adults.

Due to high estimate uncertainty for many block group estimates of the number of people living in low income households, some records cannot be reliably assigned a class and class code comparable to those assigned to race/ethnicity data from the decennial Census.

"Relative concentration" is a measure that compares the proportion of population within each Census block group data unit to the proportion of all people that live within the 13,312 block groups in the Southern California RRK region. See the "Data Units" description below for how these relative concentrations are broken into categories in this "low income" metric.

Data and Resources

Additional Info

Field Value
Version Version 5.0
Last Updated March 28, 2025, 08:36 (UTC)
Created March 7, 2025, 07:52 (UTC)
categorical_values {"99": 3580914, "1": 8248828, "2": 4243014, "0": 807075, "4": 1947482, "3": 1706416, "6": 328706, "5": 944667, "7": 7261}
category /Social and Cultural Well-Being/Equitable Opportunity/Low Income Population Concentration
collection_name California Landscape Metrics
creation_method Data are reported in Census block groups. Standard block groups are clusters of Census blocks within the same census tract that have the same first digit of their 4-character census block number (e.g., Blocks 3001, 3002, 3003 to 3999 in census tract 1210.02 belong to block group 3). Block groups delineated for the 2020 Census generally contain 600 to 3,000 people. Census blocks are statistical areas bounded on all sides by visible features(e.g., streets, roads, streams, and railroad tracks), and by non-visibleboundaries (e.g., city, town, township, county limits, and short line-of-sightextensions of streets and roads). Census blocks in suburban and rural areasmay be large, irregular, and bounded by a variety of features (e.g., roads,streams, and/or transmission line rights-of-way). In remote areas, censusblocks may encompass hundreds of square miles. Census blocks cover allterritory in the United States, Puerto Rico, and the Island areas. Blocks donot cross the boundaries of any entity for which the Census Bureau tabulatesdata. See note 1.Data describing concentrations of population characteristics that arepotentially related to environmental justice issues were provided to CWIthrough a collaboration with the USDA Forest Service, Geospatial Technologyand Applications Center. The concentration methodology was created by GTAC forsocial science analysis applications within the Forest Service; it is based onresearch published in 2018 and 2020 (See Note 2). Data were compiled andprepared for incorporating in the Task Force regions by Mark Adams,Geographer, USFS-GTAC. For more information, contact:[mark.adams1@usda.gov](mailto:mark.adams1@usda.gov).Notes: The pixels attributed with a categorical data unit describing therelative concentration of LOW_INCOME population are derived from a vectorpolygon feature that has been modified as follows: Census block groups fromthe Census Bureau's TIGER/Line geodatabase features for 2021 are selectedbased on their spatial intersection with the Southern California RRK boundary.The resulting 13,312 block group features are modified by first erasing fromthe feature the area of all constituent Census blocks which have neitherhousing nor population recorded in the PL-94171 Redistricting dataset for2020. In a second step, areas of federal and state public lands on whichhousing by definition is not located are erased from the interim feature. Theresult is a block group feature that depicts to the maximum practicable extentthe areas within the block group where people that are represented by theCensus Bureau's Census count could actually be residing. It is this modifiedblock group feature that has been rasterized to match the 30m pixel grid thatall biophysical datasets are reported in.References for the concentration levels analysis:\- Adams, Mark D. O. and S. Charnley. 2020. The Environmental JusticeImplications of Managing Hazardous Fuels on Federal Forest Lands, Annals ofthe American Association of Geographers, 110:6, 1907-1935, DOI:10.1080/24694452.2020.1727307\- Adams, Mark D. O. and S. Charnley. 2018. Environmental justice and U.S.Forest Service hazardous fuels reduction: A spatial method for impactassessment of federal resource management actions.https://doi.org/10.1016/j.apgeog.2017.12.014
data_resolution 30m Raster
data_units Categorical - Class Code 0: Zero or nearly zero. The variable is absent (observed value = 0) or is very low; the local proportion of the subject population variable is 10% or less than the same proportion in the Southern California region population in total - Class Code 1: Low. The subject population concentration is low; the local proportion of the subject population variable is between roughly 10% and 50% of the corresponding proportion in the Southern California region population in total - Class Code 2: Somewhat low. The subject population concentration is somewhat low; the local proportion of the subject population variable is between roughly 50% and 85% of the corresponding proportion in the Southern California region population in total - Class Code 3: Proportionate. The subject population concentration is roughly proportionate to the corresponding proportion in the Southern California region population in total - from about 85% to 115% of the regional proportion - Class Code 4: Somewhat high. The subject population concentration is somewhat high; the local proportion of the subject population variable is between roughly 115% and 150% of the corresponding proportion in the Southern California region population in total - Class Code 5: High. The subject population concentration is high; the local proportion of the subject population variable is between roughly 150% and 200% of the corresponding proportion in the Southern California region population in total - Class Code 6: Very high. The subject population concentration is very high; the local proportion of the subject population variable roughly 2 to 3 times that of the corresponding proportion in the Southern California region population in total - Class Code 7: Extremely high. The subject population concentration is very extremely high; the local proportion of the subject population variable is at least 3 times that of the corresponding proportion in the Southern California region population in total (the upper limit is determined by natural breaks if exceptional outliers are present, but is typically over 6 times (600%) - Class Code 99: Unclassifiable. The 90% confidence interval for the estimate is wide enough to cause the values to span four or more classes. In these cases, it is impossible to say with any reasonable certainty whether the concentration is "low" or "high."
data_vintage 2020
date_updated August 2024
element Equitable Opportunity
encoding utf8
file_name SoCal_LowIncome_2020_202312_T2_v5
format GeoTiff
harvest_object_id 36a194fe-12ce-4615-b2db-669c4e2f9b88
harvest_source_id a2637971-af12-457f-ae4a-831d2202a539
harvest_source_title WIFIRE Commons
maximum_value 99.0
metric_definition_and_relevance Relative concentration of the estimated number of people in the Southern California region that live in a household defined as "low income." There are multiple ways to define low income. These data apply the most common standard: low income population consists of all members of households that collectively have income less than twice the federal poverty threshold that applies to their household type. Household type refers to the household's resident composition: the number of independent adults plus dependents that can be of any age, from children to elderly. For example, a household with four people '€“ one working adult parent and three dependent children '€“ has a different poverty threshold than a household comprised of four unrelated independent adults. Due to high estimate uncertainty for many block group estimates of the numberof people living in low income households, some records cannot be reliablyassigned a class and class code comparable to those assigned to race/ethnicitydata from the decennial Census."Relative concentration" is a measure that compares the proportion ofpopulation within each Census block group data unit to the proportion of allpeople that live within the 13,312 block groups in the Southern California RRKregion. See the "Data Units" description below for how these relativeconcentrations are broken into categories in this "low income" metric.
minimum_value 0.0
pillar Social and Cultural Well-Being
spatial {"type": "Polygon", "coordinates": [[[-120.67507971695304, 32.49712128212305], [-115.77464954452921, 32.49712128212305], [-115.77464954452921, 35.286938865864286], [-120.67507971695304, 35.286938865864286], [-120.67507971695304, 32.49712128212305]]]}
sub_element Low Income Population Concentration
tier 2