Satellite images show how air pollution has changed during the pandemic
By
Adriana Navarro, AccuWeather staff writer
Published Apr 6, 2020 8:33 PM EDT
Experts believe air pollution levels in the U.S. have not dropped as rapidly as some areas in Europe and Asia, where millions have been ordered to stay at home.
Eyes have turned to American skies in hopes of seeing mirror images of the China and Italy satellite photos showing cleared pollution after major cities were locked down to slow the spread of the new coronavirus, but scientists warn the same narrative may not hold for every area.
In fact, Plume Labs, an environmental technology company that maps out pollution levels around the world, and its founder and CEO, Romain Lacombe, expect the drop in air pollution won't be as drastic in metropolitan cities in the U.S. as what the world has seen above cities in Europe and China.
Visit accuweather.com/airquality
After observing the first few days of confinement in places like Los Angeles, Chicago and New York City, Lacombe told AccuWeather in a Skype interview that Plume Labs predicts "the decrease in pollution is not strong enough to be noticeable behind the noise in the changes in the weather from day to day."
Plume Labs provided AccuWeather data on Brussels, Paris and Madrid, measuring the average Nitrogen dioxide (NO2) levels before and after about a week-long period of observation. NO2 is a polluting gas that Lacombe points out has a recognizable smell, about the same as what can be noticed while standing behind an idling bus or truck.
The snapshots from before in Paris and Brussels is the average amount of NO2 levels throughout the entire day of March 16, 2020. The snapshot from before in Madrid is the average amount NO2 levels throughout the entire day of March 10, 2020.
Brussels, Belgium, March 16, 2020, compared to March 21 to March 24, 2020.
Paris, France, March 16, 2020, compared to March 21 to March 24, 2020.
Madrid, Spain, March 10, 2020, compared to March 21 to March 24, 2020.
While the levels of NO2 were mostly down, Plume Labs still saw spikes in other pollutants, such as particulate matter and ground ozone.
Particulate matter is a type of small, fine dust in the air that's practically invisible, but it works its way into the lungs. These particles alone can cause serious health impacts such as cardiovascular disease and respiratory illnesses, which can then lead to heart attacks, aggravated asthma and decreasing lung function, Robbie Parks, a post-doctoral research fellow at the Earth Institute of Columbia University told AccuWeather in a Skype interview. People with these health issues are also listed as being at-risk for contracting COVID-19.
Ground ozone typically evolves from primary pollutants due to the ultraviolet (UV) rays of the sun and is capable of burning the lungs.
“The ozone in the stratosphere is up in the layers of the atmosphere. It’s important to protect ourselves from UV levels, but at the level of the ground, it’s one of the most harmful pollutants for our lungs," Lacombe said. "It’s known to trigger allergies and asthma crisis.”
Plume Labs observed a rise in these two pollutants during the ongoing shutdown, which LaCombe attributes partially to agricultural activities outside of the city. Fertilizer can be a factor in this, especially when the Northern Hemisphere enters springtime as air quality and weather are closely intertwined.
Maria Rivera, a 42-year-old seasonal worker, wears face mask to protect against coronavirus while collecting white asparagus from the field using lanterns in Uterga, around 15 km (9 miles) from Pamplona, northern Spain, Sunday, April 5, 2020. (AP Photo/Alvaro Barrientos)
"Weather is one of the, if not the most important parameter in how air quality changes," Lacombe said. "If there's a lot of winds, particulate matter, the dust in the air, is going to be chased away. If there's rain falling down, it will absorb some of the harmful gases that are in the atmosphere."
The UV rays from the sun, however, turn gases emitted into the atmosphere from driving, cooking, heating homes and powering factories into ozone and other harmful pollutants. Cloud cover can prevent or slow this process.
"The links between the pollutants, between the temperature, between sun angle, between whether or not the sky's overcast or clear -- it's really a complex set of equations," Lacombe said. "And so what scientists are trying to do and what atmospheric scientists and forecasters are trying to do is boil down all the science on the chemical pathways, on the types of reactions of what is happening in the sky."
It's due to this interaction between pollutants and weather that brings up the concern of how the changing of seasons will affect air quality.
"As we're entering the turn of the season, watch out for at least the possibility of higher air pollution levels," Lacombe said.
With rain comes the suppression of particulate matter, but spring also marks the time when smog levels are up and particulate matter peaks in some area due to agricultural activity, according to Lacombe. The higher amount of pollution in the air, not to mention the addition of pollen, could pose a threat to coronavirus survivors left with respiratory issues.
"It turns out that if you can have the best forecast, which AccuWeather is known for, it becomes much easier to forecast how air pollution is going to change, because it can have a drastic impact on the level of air quality," Lacombe said.
CLICK HERE FOR THE FREE ACCUWEATHER APP
For comparison to the data from European cities, Plume Labs sent data on Chicago, Los Angeles and New York City, also measuring the average NO2 levels before and after about a week of observation, from March 24 to April 1.
Chicago, Illinois, March 24, 2020, compared to April 1, 2020.
Los Angeles, California, March 24, 2020, compared to April 1, 2020.
New York City, New York, March 24, 2020, compared to April 1, 2020.
In Los Angeles, there was a slight increase in NO2 levels near Chinatown and Saint James Park since stay-at-home orders were issued, possibly due to more truck traffic and deliveries.
"We might see traffic go down very significantly because people are stuck at home, but deliveries (in the U.S.) are still going on," Lacombe pointed out.
Industries and factories continue to churn out emissions in the U.S., delivery trucks distributing the goods on mostly clear roads. However, even with the smaller cars off the roads, their absence doesn't make as much of an impact on emissions, according to Lacombe.
The San Gabriel Mountains are seen from the Interstate 10 in East Los Angeles, Monday, March 30, 2020. Excellent air quality has resulted from business closures during the coronavirus pandemic and recent rain. The area's famous freeway have been nearly empty, but experts say the lack of cars is contributing only a small amount to the clear skies. Researchers are analyzing just how much emissions have dropped. (AP Photo/Damian Dovarganes)
"Cars only account for 9 percent of emissions for nitrogen dioxide in the Los Angeles area," Lacombe said. "Trucks account for about half of them."
This in part is due to the fuel, according to Lacombe, and also why Europe has seen such a dramatic drop in emissions. European cars tend to use diesel as fuel -- the same fuel American delivery trucks use that is creating the bulk of the emissions. Take those emissions away from the streets of a city like Paris, and the difference in emissions is much more dramatic.
Narrow city infrastructure in western Europe tends to shield emissions from the wind compared to the sprawling roads and cities of America, which adds to the contrasts in observed air pollution levels.
"The streets are much more narrow, so emissions from traffic would stay there," Lacombe said. "So if you remove traffic from the equation, that's going to improve things much better."
View of the deserted Opera avenue during nationwide confinement measures to counter counter the Covid-19, in Paris, Monday, April 6, 2020. (AP Photo/Thibault Camus)
Lacombe points out two main concerns as to why monitoring air pollution and air quality are critical in the context of COVID-19.
First, COVID-19 disease has had a devastating impact on respiratory systems. The shortage of respirators across the U.S., especially in New York, has shown just how much of a punch the worst cases of the virus can deliver.
"If air quality levels are really poor, that can only worsen things, and it might actually, in fact, make it harder as well for people to recover from the infection of the virus," Lacombe said.
Second, the virus could bind and travel through different air pollutants, though Lacombe is careful to point out that whether SARS-CoV-2, the virus that causes COVID-19, behaves this way is an educated suspicion among scientists.
"There could be a possibility that it binds to particulate matter," Lacombe said. "We knew that this can happen for other types of viruses, and in this case, it means that hydrogen levels in pollution could actually help spread the virus."
Lacombe stresses that this is still a hypothesis, and it is too early to tell for certain. However, he points out his hope is that since COVID-19 is a respiratory illness, keeping the level of air quality in check will lessen the severity of the illness, aid in recovery and, should the air quality and transmission be connected, help flatten the curve.
"It probably might take months to prove this hypothesis, but if it turns out that there's a link between particulate matter levels and pollution levels and the transmission of the virus, then everything we can do to keep that level down is going to help flatten the curve as we're trying to do," Lacombe said.
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News / Health
Satellite images show how air pollution has changed during the pandemic
By Adriana Navarro, AccuWeather staff writer
Published Apr 6, 2020 8:33 PM EDT
Experts believe air pollution levels in the U.S. have not dropped as rapidly as some areas in Europe and Asia, where millions have been ordered to stay at home.
Eyes have turned to American skies in hopes of seeing mirror images of the China and Italy satellite photos showing cleared pollution after major cities were locked down to slow the spread of the new coronavirus, but scientists warn the same narrative may not hold for every area.
In fact, Plume Labs, an environmental technology company that maps out pollution levels around the world, and its founder and CEO, Romain Lacombe, expect the drop in air pollution won't be as drastic in metropolitan cities in the U.S. as what the world has seen above cities in Europe and China.
Visit accuweather.com/airquality
After observing the first few days of confinement in places like Los Angeles, Chicago and New York City, Lacombe told AccuWeather in a Skype interview that Plume Labs predicts "the decrease in pollution is not strong enough to be noticeable behind the noise in the changes in the weather from day to day."
Plume Labs provided AccuWeather data on Brussels, Paris and Madrid, measuring the average Nitrogen dioxide (NO2) levels before and after about a week-long period of observation. NO2 is a polluting gas that Lacombe points out has a recognizable smell, about the same as what can be noticed while standing behind an idling bus or truck.
The snapshots from before in Paris and Brussels is the average amount of NO2 levels throughout the entire day of March 16, 2020. The snapshot from before in Madrid is the average amount NO2 levels throughout the entire day of March 10, 2020.
Brussels, Belgium, March 16, 2020, compared to March 21 to March 24, 2020.
Paris, France, March 16, 2020, compared to March 21 to March 24, 2020.
Madrid, Spain, March 10, 2020, compared to March 21 to March 24, 2020.
While the levels of NO2 were mostly down, Plume Labs still saw spikes in other pollutants, such as particulate matter and ground ozone.
Particulate matter is a type of small, fine dust in the air that's practically invisible, but it works its way into the lungs. These particles alone can cause serious health impacts such as cardiovascular disease and respiratory illnesses, which can then lead to heart attacks, aggravated asthma and decreasing lung function, Robbie Parks, a post-doctoral research fellow at the Earth Institute of Columbia University told AccuWeather in a Skype interview. People with these health issues are also listed as being at-risk for contracting COVID-19.
Ground ozone typically evolves from primary pollutants due to the ultraviolet (UV) rays of the sun and is capable of burning the lungs.
“The ozone in the stratosphere is up in the layers of the atmosphere. It’s important to protect ourselves from UV levels, but at the level of the ground, it’s one of the most harmful pollutants for our lungs," Lacombe said. "It’s known to trigger allergies and asthma crisis.”
Plume Labs observed a rise in these two pollutants during the ongoing shutdown, which LaCombe attributes partially to agricultural activities outside of the city. Fertilizer can be a factor in this, especially when the Northern Hemisphere enters springtime as air quality and weather are closely intertwined.
Maria Rivera, a 42-year-old seasonal worker, wears face mask to protect against coronavirus while collecting white asparagus from the field using lanterns in Uterga, around 15 km (9 miles) from Pamplona, northern Spain, Sunday, April 5, 2020. (AP Photo/Alvaro Barrientos)
"Weather is one of the, if not the most important parameter in how air quality changes," Lacombe said. "If there's a lot of winds, particulate matter, the dust in the air, is going to be chased away. If there's rain falling down, it will absorb some of the harmful gases that are in the atmosphere."
The UV rays from the sun, however, turn gases emitted into the atmosphere from driving, cooking, heating homes and powering factories into ozone and other harmful pollutants. Cloud cover can prevent or slow this process.
"The links between the pollutants, between the temperature, between sun angle, between whether or not the sky's overcast or clear -- it's really a complex set of equations," Lacombe said. "And so what scientists are trying to do and what atmospheric scientists and forecasters are trying to do is boil down all the science on the chemical pathways, on the types of reactions of what is happening in the sky."
It's due to this interaction between pollutants and weather that brings up the concern of how the changing of seasons will affect air quality.
"As we're entering the turn of the season, watch out for at least the possibility of higher air pollution levels," Lacombe said.
With rain comes the suppression of particulate matter, but spring also marks the time when smog levels are up and particulate matter peaks in some area due to agricultural activity, according to Lacombe. The higher amount of pollution in the air, not to mention the addition of pollen, could pose a threat to coronavirus survivors left with respiratory issues.
"It turns out that if you can have the best forecast, which AccuWeather is known for, it becomes much easier to forecast how air pollution is going to change, because it can have a drastic impact on the level of air quality," Lacombe said.
CLICK HERE FOR THE FREE ACCUWEATHER APP
For comparison to the data from European cities, Plume Labs sent data on Chicago, Los Angeles and New York City, also measuring the average NO2 levels before and after about a week of observation, from March 24 to April 1.
Chicago, Illinois, March 24, 2020, compared to April 1, 2020.
Los Angeles, California, March 24, 2020, compared to April 1, 2020.
New York City, New York, March 24, 2020, compared to April 1, 2020.
In Los Angeles, there was a slight increase in NO2 levels near Chinatown and Saint James Park since stay-at-home orders were issued, possibly due to more truck traffic and deliveries.
"We might see traffic go down very significantly because people are stuck at home, but deliveries (in the U.S.) are still going on," Lacombe pointed out.
Industries and factories continue to churn out emissions in the U.S., delivery trucks distributing the goods on mostly clear roads. However, even with the smaller cars off the roads, their absence doesn't make as much of an impact on emissions, according to Lacombe.
The San Gabriel Mountains are seen from the Interstate 10 in East Los Angeles, Monday, March 30, 2020. Excellent air quality has resulted from business closures during the coronavirus pandemic and recent rain. The area's famous freeway have been nearly empty, but experts say the lack of cars is contributing only a small amount to the clear skies. Researchers are analyzing just how much emissions have dropped. (AP Photo/Damian Dovarganes)
"Cars only account for 9 percent of emissions for nitrogen dioxide in the Los Angeles area," Lacombe said. "Trucks account for about half of them."
This in part is due to the fuel, according to Lacombe, and also why Europe has seen such a dramatic drop in emissions. European cars tend to use diesel as fuel -- the same fuel American delivery trucks use that is creating the bulk of the emissions. Take those emissions away from the streets of a city like Paris, and the difference in emissions is much more dramatic.
Narrow city infrastructure in western Europe tends to shield emissions from the wind compared to the sprawling roads and cities of America, which adds to the contrasts in observed air pollution levels.
"The streets are much more narrow, so emissions from traffic would stay there," Lacombe said. "So if you remove traffic from the equation, that's going to improve things much better."
View of the deserted Opera avenue during nationwide confinement measures to counter counter the Covid-19, in Paris, Monday, April 6, 2020. (AP Photo/Thibault Camus)
Lacombe points out two main concerns as to why monitoring air pollution and air quality are critical in the context of COVID-19.
First, COVID-19 disease has had a devastating impact on respiratory systems. The shortage of respirators across the U.S., especially in New York, has shown just how much of a punch the worst cases of the virus can deliver.
"If air quality levels are really poor, that can only worsen things, and it might actually, in fact, make it harder as well for people to recover from the infection of the virus," Lacombe said.
Second, the virus could bind and travel through different air pollutants, though Lacombe is careful to point out that whether SARS-CoV-2, the virus that causes COVID-19, behaves this way is an educated suspicion among scientists.
"There could be a possibility that it binds to particulate matter," Lacombe said. "We knew that this can happen for other types of viruses, and in this case, it means that hydrogen levels in pollution could actually help spread the virus."
Lacombe stresses that this is still a hypothesis, and it is too early to tell for certain. However, he points out his hope is that since COVID-19 is a respiratory illness, keeping the level of air quality in check will lessen the severity of the illness, aid in recovery and, should the air quality and transmission be connected, help flatten the curve.
"It probably might take months to prove this hypothesis, but if it turns out that there's a link between particulate matter levels and pollution levels and the transmission of the virus, then everything we can do to keep that level down is going to help flatten the curve as we're trying to do," Lacombe said.
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