2020 U.S. Transportation
Climate Impact Index

Methodology

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Overview and The Top 10 ⟶
The Complete List: Top 100 Metros and How They Rank ⟶
Best and Worst: Rankings by Key Indices ⟶
Climate Index Methodology

StreetLight analyzed the 100 most populous metro areas from the 2018 U.S. Census list of core-based statistical areas (CBSAs). We scored the cities individually, per capita, by four StreetLight-derived factors: Vehicle miles traveled (VMT), bike commuting, pedestrian commuting, and circuity. We added two factors: density, calculated by dividing geographic area by population, and transit ridership, ranked according to the American Public Transportation Association’s per-capita ridership ratings. 

StreetLight analyzes trips derived from location-based services (LBS) data, processed by our proprietary algorithm. Results were indexed values, not actual measurements, because StreetLight does not capture 100% of a city’s movements. Overall rankings were derived using each individual factor’s value scaled from 0 to a factor’s weight. A higher ranking indicates a better score, with a lower ranking indicating a worse score, relative to other cities. 

We weighted factors as follows: 

VEHICLE MILES TRAVELED (VMT) >

VMT weighted at 9 due to its direct contribution to greenhouse gas emissions.

BIKE >

Bike commuting weighted at 4 because it replaces regular vehicle trips with zero-emission transportation.

PEDESTRIAN >

Pedestrian commuting weighted at 3 because it tends to replace shorter vehicle trips than cycling.

TRANSIT >

Transit weighted at 2 because although it does move people more efficiently than personal vehicles, it is not a zero-emission mode, and not every city has the resources for transit infrastructure.

CIRCUITY >

Circuity weighted at 1 because although it affects VMT, its effect is more indirect than other factors.

DENSITY>

Density weighted at 1 because its connection to vehicle transportation is indirect, and it is not managed by transportation experts.

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About StreetLight Data

StreetLight Data pioneered the use of Big Data analytics to help transportation professionals solve their biggest problems. Applying proprietary machine-learning algorithms to over four trillion spatial data points, StreetLight measures diverse travel patterns and makes them available on-demand via the world’s first SaaS platform for mobility, StreetLight InSight®. From identifying sources of congestion to optimizing new infrastructure to planning for autonomous vehicles, StreetLight powers more than 3,000 projects every month.

Learn More About the Climate Impact Index

Overview and The Top 10

The Complete List: Top 100 Metros and How They Rank

Bike against brick wall

Best and Worst: Rankings by Key Indices

Learn More About the Climate Impact Index

Overview and The Top 10

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The Complete List: Top 100 Metros and How They Rank

READ MORE
Bike against brick wall

Best and Worst: Rankings by Key Indices

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