This line chart visualizes one week of temperature data in San Francisco, sourced from the Data Canvas - Sense Your City initiative. It plots timestamp on the x-axis against temperature in degrees Celsius on the y-axis, with a smooth curve fitted using D3's `line` and `curveBasis`. The visualization is rendered as an SVG, using D3 v5 APIs like `scaleTime`, `scaleLinear`, `axisLeft`, `axisBottom`, and `nest` to group data by city, with a categorical color scale from `SchemeCategory10` assigning distinct stroke colors to each series.