Data Visualization in Environmental Public Health: From Data to Insight
Figure 8 Density Map Example: Food Inspection Violations
Density Maps In GIS, a density map uses the
locations of individual observations to estimate where events are more or less concentrated across a geographic area. Color intensity represents the estimated density of events, such as clusters of environmental health complaints. Examples include: • Environmental health complaints • Mosquito observations or activity reports • Environmental sampling events • Repeated environmental incidents Density maps are particularly useful for identifying clusters, hotspots, and areas of concentrated activity that could warrant further investigation. They show the concentration of observations, not necessarily the severity of a condition. For example, a density map of environmental sampling events would show where more samples were collected, not where contaminant levels were highest. Density maps are sometimes called geographic heat maps. They differ, however, from the heat maps used in general data visualization. A heat map compares values across categories in a grid or matrix, while a density map shows the estimated geographic concentration of observations.
Map image is the intellectual property of Esri and is used herein under license. Copyright © 2026 Esri and its licensors. All rights reserved. Data: King County Food Establishment Inspections, 2022–2025 Sources: Esri, TomTom, Garmin, FAO, NOAA, USGS, © OpenStreetMap
15
Powered by FlippingBook