When scientists switched on instruments on a new satellite this summer, they previewed what will soon be the first continuous record of air pollution in the country.
The satellite will continue to station over North America, providing scientists with daily updates on air pollution across the country.
On Thursday, the researchers released their first images showing pollution changes Nitrogen dioxide levels over the United States in one day.
“It’s really exciting to see the instrument work as expected,” said Xiong Liu, a physicist at the Center for Astrophysics operated by Harvard University and the Smithsonian Institution, and deputy director of the mission.
The satellite instrument, called TEMPO, will also be able to measure other pollutants.
The images were taken during the summer, when the air quality in the United States was exceptionally poor and smoke from wildfires blanketed several cities and regions.
But even before this summer, over the past decade, the air quality improvements Americans have enjoyed since the passage of the Clean Air Act in 1970 had begun stagnate.
Although air pollution has improved over the years, “one in three Americans still live with unhealthy air pollution levels,” Liu said.
Nitrogen dioxide comes from fuel combustion and produces other types of pollution through chemical reactions in the air.
The picture shows clearly hotspot Concentrations of natural gas are higher around large cities and are higher in the morning and evening when there is more traffic.
As well as observing Earth via new satellites, scientists toured the country on foot and in research aircraft in July and August, an elaborate show trying to understand the causes of declining air quality No longer improving.
Because pollutants can travel thousands of miles quickly by wind, scientists are finding it difficult to pinpoint the largest sources of pollution across the country.
Brian McDonald, an environmental engineer at the National Oceanic and Atmospheric Administration (NOAA) who is coordinating this summer’s satellite field study, said TEMPO’s hourly updates are expected to be “a real game changer.” , allowing researchers to trace air pollution to its source.
he car traffic It has historically been one of the biggest sources of air pollution, but tightening of motor vehicle emissions standards has reduced pollution from driving.
At the same time, the relative importance of consumer products and materials that emit VOC pollutants, such as paints and pesticides, has increased, MacDonald explained.
deadly combination
These compounds react with nitrogen dioxide in the air to produce harmful ozone In some places, notably in California and major metropolitan areas across the country, ground elevations remain persistently high.
While the ozone layer high in the atmosphere protects us from cancer-causing ultraviolet radiation, ozone near the ground can exacerbate or cause cancer. Respiratory Diseases Such as asthma, bronchitis and emphysema.
Another long-standing problem is fine particle pollution, which consists of tiny particles small enough to enter the bloodstream, causing heart and lung disease, stroke and, in severe cases, even premature death.
This pollution, also known as PM2.5, started rising again around 2016 after years of decline.
this Forest fireAs climate change creates hotter, drier conditions, this phenomenon becomes more frequent and intense, which appears to be main in-charge A study published last fall suggests this setback.
Marshall Burke, a professor of environmental policy at Stanford University and one of the study’s authors, said the study was based on an old satellite that provided routine measurements.
He and his colleagues rely heavily on computer models of how pollutants move in the wind to fill in the gaps between actual observations.
Burke, who was not involved with the TEMPO mission, looks forward to the satellite’s hourly data, which he says is “more like video.”
“As more images become available, it becomes easier to fill out maps of where things come from,” he added.
TEMPO will be able to track air pollution at a resolution of about 6 square kilometers.
That’s where a coordinated flight, commute, and walk comes into play this summer.
Tracey Holloway, a professor of energy policy and analysis at the University of Wisconsin-Madison who studies air quality but was not involved in the project, said “the data from these field surveys act as a decoder ring” for satellite instruments. .
New York is one of the places where scientists collected data locally. Even cities that conduct routine air inspections often don’t have enough equipment to cover every neighborhood.
This is a problem because air pollution is often unevenly distributed within the same city or region.
Since late July, a dozen researchers led by NOAA’s Audrey Gaudel and Prathap Ramamurthy have been studying New York’s air pollution.
Analyzing all the data will take months, but the walk itself has revealed a link between climate change and air quality. (Some hour-long rides in the height of summer are “terrible,” Ramamurthy said.)
Higher temperatures are generally associated with higher levels of ozone pollution, and on the hottest sampling day, ozone readings exceeded national standards set by the Environmental Protection Agency, Gaudel said.
Data from the TEMPO satellite will be made available to the public this spring. Meanwhile, more than 400 users, including many state and federal agencies, have registered as “early adopter“(early adopters).
Researchers at New York’s Mount Sinai Health System plan to use TEMPO data to study how air pollutants affect symptoms Asthma in children.
The Connecticut Office of Air Management plans to use the data to investigate where the state’s unusually high ozone pollution is coming from.
Ornelas van Horn hopes this summer’s research will give policymakers the information they need to address the country’s persistent air quality problems.
“We can all agree that air pollution is bad,” he said.
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