{"version":"1.0","type":"rich","title":"Two Decades of Pollution in US","description":"This visualization shows PM2.5 pollution across US counties for the year 2000, using a choropleth map colored by concentration levels. It builds the map with vega-lite-api, joining county GeoJSON topojson data with a PM2.5 CSV dataset via a lookup transform. The visualization uses an Albers USA projection, encodes the pollution values on a clamped color scale, and renders tooltips showing exact concentrations. It integrates D3 version 5 and React for the interface setup.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/39e845953d7547e5b2b8aede08714d87?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}