{"version":"1.0","type":"rich","title":"Pollution in US with counties with color legend","description":"A choropleth map of the United States displays PM2.5 concentration levels for counties in the year 2000, using a sequential YlGnBu color scale from d3.interpolateYlGnBu. County boundaries come from the US Atlas TopoJSON file, rendered as SVG paths via d3.geoPath and geoIdentity. A linear gradient legend annotates the concentration scale. Data is loaded from a CSV using d3.csv and filtered into a Map for lookup. The visualization is built with React and D3 v5.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/e6e0e07c8ff8402db592d5e044f4f436?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}