                   4, 1
                        ],
// Increase the heatmap color weight by zoom level
// heatmap-intensity is a multiplier on top of heatmap-weight
                        'heatmap-intensity': [
                            'interpolate',
                            ['linear'],
                            ['zoom'],
                            0, 1,
                            9, 3
                        ],
// Color ramp for heatmap.  Domain is 0 (low) to 1 (high).
// Begin color ramp at 0-st