Using available data for San Diego and comparative metropolitan areas, Insight San Diego measured the number of unhealthy air days, amount of CO2 emitted in traffic and number of LEED certified buildings in each area to develop the Air Quality grade.
The Unhealthy Air Days indicator measures the number of days in which San Diego County’s air quality is considered unhealthy for sensitive groups (i.e. elderly adults and children), according to the Environmental Protection Agency. Vehicle emissions continue to be one of the major challenges to improving air quality in the San Diego region.
CO2 emitted in traffic is not only a climate change driver, but also contributes to air pollution and unhealthy air days. On-road transportation continues to be the largest emitter of CO2 in San Diego, representing more than 40% of emissions in the County.
(1) LEED certified buildings, those designed to be more efficient in the use of natural resources, including energy, and often using clean, renewable energy, contribute to cleaner air by reducing the need for fossil fuel based electricity generation. In San Diego County, electricity use contributes to around 25% of CO2 emissions.
(2) Around the nation, electric power plants emit about 2.2 billion tons of CO2 each year, or roughly 40% of the nation’s total emissions.
(3) These three indicators make up the available data score for Air Quality in San Diego and other metropolitan areas.