Urban Tree Canopy GIS Layers

The Urban Tree Canopy Viewer contains the following layers:

  • Urban area boundaries 2012- from the U.S. Census Bureau.
  • CA census tracts-  from the U.S. Census Bureau.
  • Urban Tree Canopy 2018- The urban tree canopy cover map was created by EarthDefine, based on 2018 National Agriculture Imagery Program (NAIP) aerial imagery and LiDAR data collected by the U.S. Geological Survey. The NAIP imagery was acquired during the growing season and included four spectral bands (red, green, blue, and near infrared) at 60-cm spatial resolution.
  • Percent canopy cover- generated from the urban tree canopy layer. Percent canopy cover of census tract.
  • Population size 2010- acquired by CalEnviroScreen 3.0 from Esri, Inc., based on the U.S. Census Bureau’s 2010 census.
  • Poverty incidence- CalEnviroScreen 3.0 indicator of the percent of the population living below two times the federal poverty level (5-year estimate, 2011-2015).
  • Asthma incidence- CalEnviroScreen 3.0 indicator of the number of asthma emergency department visits per 10,000 people for the years 2011-2013.
  • Cardiovascular disease incidence- CalEnviroScreen 3.0 indicator of the number of heart attack emergency department visits per 10,000 people for the years 2011-2013.
  • Ozone pollution- CalEnviroScreen 3.0 indicator of the daily maximum 8-hour ozone concentrations extracted from the air monitors for 2012-2013.
  • PM 2.5 pollution- CalEnviroScreen 3.0 indicator of the quarterly means extracted from the air monitors for 2012-2014 and a mean was calculated by averaging across the three years.
  • Water body impairment- CalEnviroScreen 3.0 indicator combines the number of pollutants in all water bodies designated as impaired in each census tract.
  • Urban Heat Island Index- CalEPA’s Index is calculated as a positive temperature differential over time between an urban census tract and nearby upwind rural reference points at a height of two meters above ground level, where people experience heat. The Index is reported in degree-hours per day on a Celsius scale.

For more detailed information on the layers featured in this map viewer, please visit:

http://www.earthdefine.com/spatialcover_treecanopy/

https://oehha.ca.gov/calenviroscreen

https://calepa.ca.gov/climate/urban-heat-island-index-for-california/