For one day, Philly residents will take to sweltering streets to measure heat and pollution

One blistering day this summer, dozens of Philly residents, trained as “community scientists,” will drive specially equipped cars through most of the city to collect temperature and air-quality data as part of a study overseen by the federal Oceanic and Atmospheric Administration.

Philly was one of 16 communities in the United States and abroad announced Tuesday as chosen by NOAA to study the urban heat island effect — when temperatures in areas with little shade and lots of concrete and asphalt can spike 15 to 20 degrees warmer than surrounding areas.

Scientists want to better understand the impact of that heat and pollution, especially on communities of color. Extreme heat kills more people than any other weather event, according to federal authorities, who say climate change is exacerbating the issue.

The study is part of an effort by the National Integrated Heat Health Information System (NIHHIS), in partnership with CAPA Strategies. The NIHHIS is a campaign by NOAA. And CAPA is a private company that receives federal funding to capture and analyze data, as well as building digital tools used for crafting locally resiliency plans.

Communities applied between last fall and Jan. 14 to take part in the 2022 study. NOAA Administrator Richard Spinrad announced the winners at a national conference of the NIHHIS.

“Our nation faces a climate crisis that has exacerbated inequities for low-income communities and communities of color,” Spinrad said, adding that the information will be used “to inform strategies to reduce the unhealthy and deadly effects of extreme heat.”

Other communities taking part: Boulder, Colo.; Clark County, Nev. ( which includes Las Vegas); Columbia, S.C.; Columbus, Ohio; Jacksonville, Fla.; Knoxville and Nashville, Tenn.; Milwaukee; Montgomery County, Md.; Omaha, Neb.; Spokane, Wash.; Brooklyn, N.Y.; and San Francisco, as well as Freetown, Sierra Leone, and Rio de Janeiro, Brazil.

The study has been carried out in other cities since 2017. This year, Philadelphia will have a turn, and the Academy of Natural Sciences of Drexel University will take a lead role on training and assisting local volunteers.

Philly participants will map heat and air quality in the city on one of the hottest days of the year. The Academy will recruit, select, and train volunteers by May or June. It is partnering with Philadelphia Parks and Rec, the Pennsylvania Horticultural Society, Temple University professor Christina Rosan, and Russell Zerbo from the Clean Air Council.

“I’m super excited about it,” said Richard Johnson, director of community science at the Academy. “As a result of the campaign, you’ll really paint a picture of what is it like to be in Philly on a really hot day. And you’ll capture some of the community’s experiences with heat and air quality. ... We really don’t have data like that. This will really kind a human face on it.”

Johnson said volunteers will have 10 to 12 heat and air-quality sensors mounted on their vehicles, or vehicles they have access to, costing collectively about $12,000, and paid for through the study. The volunteers will cruise through the city in shifts in the morning, afternoon, and evening on a yet-to-be-chosen date.

Johnson will schedule a date after looking at a two-week forecast in July or early August, seeking the warmest sunny day.

The sensors are designed to record location temperature, humidity, and air pollution constantly as they move about. The air-quality sensors will record PM2.5, or fine particulate matter. CAPA will collect the data, analyze it, and give the city data sets, maps, sensor readings with the paths of the cars, temperature predictions, and a report of the findings for use in crafting policy.

Johnson said he expects recruits to come from already established community groups and programs. The volunteers will comb an expected 100 square miles, or more than 70% of Philly’s 140 square miles.

Though other cities have taken part in the study, Philly will be one of the few to record air quality. Areas such as Hunting Park are known hot spots. And areas such as Mount Airy in the Northwest are known to be cooler, as are areas along the major parks where there are lots of trees.

“It’ll be a pretty complete picture of the whole city,” Johnson said. “We’re prioritizing the hottest neighborhoods, but we want some comparisons. And so we want the Northwest artery in the Northeast artery as much as possible.”

Zerbo, of the Clean Air Council, said heat and pollutants mix to affect human respiratory systems. So having those kinds of data is valuable.

Pollution spewed by cars mixes with sunlight to kick off a chemical reaction that causes ozone levels to soar.

The Philadelphia Department of Public Health’s Air Management Services has been collecting data since 2018 from 50 air-monitoring locations set up across the city to gauge air pollution by neighborhood.

Particulate matter, or PM2.5, defined as concentrations of 2.5 microns or smaller, is of special concern because the particles are so small — far smaller than the width of a human hair — that they are easily inhalable. The World Health Organization says PM2.5 is responsible for the biggest proportion of health effects from air pollution.

» READ MORE: Philly’s air pollution soars in summer. This neighborhood has the worst of it.

Locally, the biggest sources of PM2.5 are emissions from gas and diesel-powered vehicles. Particles form when emissions react in the air. Health effects can stem from short or long exposure, and can range from aggravation of asthma and other respiratory illnesses to premature death in people with chronic heart or lung diseases. Children and seniors are most vulnerable.

PM2.5 concentrations in Philly measure highest in summer. The highest concentrations have been found in Center City likely because of cars and trucks stuck in traffic.

However, Zerbo said the study would give a much more comprehensive view of pollution and heat than has been available to date because it will cover such a wide area and penetrate most neighborhoods.

“The really exciting part of this is that it’s participatory,” Zerbo said. “This is going to be volunteer-based. So people who might not have thought about these issues before will all of a sudden be measuring air temperature and air quality. It should be very eye-opening for those involved.”

The Philadelphia Inquirer is one of more than 20 news organizations producing Broke in Philly, a collaborative reporting project on solutions to poverty and the city’s push toward economic justice. See all of our reporting at brokeinphilly.org.