This scatter plot visualizes the relationship between air quality (PM2.5 levels) and GDP per capita across global cities. The reusable D3 v7 chart applies logarithmic scaling with deterministic jitter to both axes, allowing dense data points to separate visually. Cities are colored by income tier (Low, Middle, High) using `d3.scaleOrdinal`, with a legend indicating the categories. The visualization uses `d3.csv` to load the dataset, `d3.scaleLinear` for axis scales, `d3.axisBottom` and `d3.axisLeft` for ticks, and includes hover tooltips displaying city details.