This scatter plot matrix reveals relationships between daily Air Quality Index, temperature, and total municipal greenhouse gas emissions in San Francisco from 2020 to 2022, with points colored by year. It combines data from two CSV files, aggregating emissions by fiscal year to join with daily weather readings. The visualization uses D3 v7's `d3.scaleLinear` for axes, `d3.rollup` for data aggregation, and `d3.schemeCategory10` for color encoding. Each cell displays dots representing individual days, with SVG circles providing interactive tooltips showing exact values.