Pima Air Quality Information http://envista.pima.gov
Tucson Census Data http://quickfacts.census.gov/qfd/states/04/0477000lk.html
University of Minnesota demographic data resources https://www.ipums.org
Census of Agriculture http://www.agcensus.usda.gov
The Arizona Meteorological Network https://ag.arizona.edu/azmet/index.html
Water Resources of the United States http://www.usgs.gov/water/
Database of animal tracking data https://www.movebank.org