How Ozone Affects Us and Why We’re Tracking it with TEMPO
The Good, The Bad, and the Ugly Side of Ozone
Ozone is a gas that both protects us from the sun and pollutes our air, depending on its altitude.
High up in the stratosphere, about 10-15 miles in the air, natural ozone blocks the sun’s UV radiation
from both warming our planet and damaging our skin. Meanwhile, down at ground level, burning fossil
fuels, wood, and garbage leads to formation of ozone in the air we breathe, where it can cause health
issues. Ozone’s broad influence on our planet’s health and wellbeing makes it a prime target for
research by the Center for Astrophysics | Harvard and Smithsonian using their space-based instrument
TEMPO.
TEMPO is a satellite-based instrument that sits in orbit over North America, scanning nearly the
entire continent for atmospheric pollution once per hour during daytime. TEMPO will track the
formation and movement of the most important pollutants in our atmosphere, including ozone and its
precursors, throughout the day to inform research and to protect life on Earth.
The space-based instruments currently used to observe air quality are not sufficient for
measuring ozone dynamics in high detail. For example, today’s satellites in low-Earth orbit do not
produce enough data to gather a clear picture of how much pollution is being emitted, where it’s
coming from, and how it varies throughout the day. These satellites also have trouble detecting ground-
level ozone. TEMPO, on the other hand, offers hourly measurements of air pollution at different heights,
which will help scientists and the public see ozone “clouds” form and spread at the community level in
near-real time.
Ozone in the upper layers of the atmosphere is beneficial because it absorbs all
of the most energetic ultraviolet radiation (UV-C), most of the UV-B radiation, and some of the least
energetic UV radiation (UV-A). But ozone in lower layers is a pollutant associated with the formation of
smog, irritation of human lungs and damage to plants.
© NASA.
How Ozone Helps and Hurts Us
Ozone forms naturally in our stratosphere when the sun’s UV light hits oxygen molecules. In
turn, this ozone blocks further UV radiation from reaching the lower atmosphere, enabling life on Earth
to exist. But that same life – specifically humans – has created even more ozone that sits near ground
level and damages our lungs and the vegetation around us. TEMPO can differentiate between ozone at
different elevations, making it useful for analyzing stratospheric and ground-level ozone separately.
Naturally occurring ozone in the stratosphere gets destroyed by pollutants in the air; namely,
manufactured chemicals that release chlorine and bromine when they encounter UV light. Ozone
depletion allows more UV-B light to reach the Earth’s surface, which could increase the incidence of skin
cancer. Elevated UV-B light can also change how plants grow and interfere with the balance of the
ecosystem. It can kill phytoplankton in the ocean, which are crucial for capturing carbon from the
atmosphere, and it can disrupt animal reproduction. Scientists’ worries about ozone depletion came to a
head in the 1980s when they detected a “hole” in the ozone layer. Thanks to a worldwide ban on the
release of ozone-eating chemicals called chlorofluorocarbons, or CFCs, the hole is shrinking. TEMPO will
help scientists track the natural ozone layer on hourly basis throughout the day to assess its strength
and its ability to block harmful UV radiation from reaching the surface of the Earth.
Ozone affects the health of both humans and the environment at ground level, as well. For
humans, the gas can cause a range of respiratory systems, from chest pain to congestion, and it can
worsen pre-existing respiratory conditions such as bronchitis and asthma. Just like how ozone interferes
with breathing in humans, it also limits breathing in plants. Notably, it limits the amount of carbon
dioxide plants can absorb and the amount of oxygen they can release. This not only damages natural
ecosystems; it also reduces crop yield on farms. Repeated studies have shown that higher ozone
concentrations in the air lead to lower yields of agricultural crops.
Ozone at ground level cannot form without sunlight, and as a result, ozone levels fluctuate
throughout the day and throughout the year in parallel with sunlight levels. For example, ground-level
ozone concentrations are often at their highest in the summer months and during the middle of the day
when the sun is more directly overhead. Rush-hour traffic can also cause a rise in ozone, as cars release
some of its main precursors, nitrogen oxides, through their exhaust pipes. Further, thunderstorms can
introduce ozone to the lower atmosphere. They pull ozone down from the stratosphere, moving it from
an area where it helps us to an area where it can cause harm. Overall, ozone levels are at their highest
when the atmosphere is warm for an extended period. During these periods, ozone levels can reach a
high enough level where they can cause throat and lung irritation and aggravate peoples’ asthma and
emphysema.
Amid all the factors that cause ozone to form, TEMPO will help scientists identify its largest
sources as well as where ozone goes after it is created. Additionally, the public will ultimately be able to
view ozone levels on a map, like doppler radar, to determine whether it is safe to go outside.
The Future of Ozone
Air pollution’s effect on our planet is multifaceted. While the world has reduced its use of
substances that damage our stratospheric ozone layer, ozone levels at ground level will continue to
threaten human health and the balance of our natural ecosystems and farms. By burning greater
volumes of fossil fuels, humans are producing more chemicals that lead ozone to form in our lower
atmosphere — into the air we breathe. Further, climate change is leading to more natural disasters such
as wildfires and more severe weather events that pump greater amounts of ozone into the air.
These ongoing changes, and their impact on life, make it critical for scientists to constantly
monitor ozone levels in our atmosphere. The data TEMPO produces will help us understand the impacts
of climate change and will help authorities develop more impactful environmental policies aimed at
reducing ozone in our lower atmosphere. Furthermore, TEMPO’s data could help better inform the
public about air quality to protect their health. Overall, TEMPO will help us understand the factors that
affect ozone in the face of industrialization and climate change and help us develop sustainable
solutions that keep our communities and our ecosystems stable and healthy for future generations.
Ozone is a gas that both protects us from the sun and pollutes our air, depending on its altitude. High up in the stratosphere, about 10-15 miles in the air, natural ozone blocks the sun’s UV radiation from both warming our planet and damaging our skin. Meanwhile, down at ground level, burning fossil fuels, wood, and garbage leads to formation of ozone in the air we breathe, where it can cause health issues. Ozone’s broad influence on our planet’s health and wellbeing makes it a prime target for research by the Center for Astrophysics | Harvard and Smithsonian using their space-based instrument TEMPO.
TEMPO is a satellite-based instrument that sits in orbit over North America, scanning nearly the entire continent for atmospheric pollution once per hour during daytime. TEMPO will track the formation and movement of the most important pollutants in our atmosphere, including ozone and its precursors, throughout the day to inform research and to protect life on Earth.
The space-based instruments currently used to observe air quality are not sufficient for measuring ozone dynamics in high detail. For example, today’s satellites in low-Earth orbit do not produce enough data to gather a clear picture of how much pollution is being emitted, where it’s coming from, and how it varies throughout the day. These satellites also have trouble detecting ground- level ozone. TEMPO, on the other hand, offers hourly measurements of air pollution at different heights, which will help scientists and the public see ozone “clouds” form and spread at the community level in near-real time.
Ozone in the upper layers of the atmosphere is beneficial because it absorbs all
of the most energetic ultraviolet radiation (UV-C), most of the UV-B radiation, and some of the least
energetic UV radiation (UV-A). But ozone in lower layers is a pollutant associated with the formation of
smog, irritation of human lungs and damage to plants.
© NASA.
How Ozone Helps and Hurts Us
Ozone forms naturally in our stratosphere when the sun’s UV light hits oxygen molecules. In turn, this ozone blocks further UV radiation from reaching the lower atmosphere, enabling life on Earth to exist. But that same life – specifically humans – has created even more ozone that sits near ground level and damages our lungs and the vegetation around us. TEMPO can differentiate between ozone at different elevations, making it useful for analyzing stratospheric and ground-level ozone separately.
Naturally occurring ozone in the stratosphere gets destroyed by pollutants in the air; namely, manufactured chemicals that release chlorine and bromine when they encounter UV light. Ozone depletion allows more UV-B light to reach the Earth’s surface, which could increase the incidence of skin cancer. Elevated UV-B light can also change how plants grow and interfere with the balance of the ecosystem. It can kill phytoplankton in the ocean, which are crucial for capturing carbon from the atmosphere, and it can disrupt animal reproduction. Scientists’ worries about ozone depletion came to a head in the 1980s when they detected a “hole” in the ozone layer. Thanks to a worldwide ban on the release of ozone-eating chemicals called chlorofluorocarbons, or CFCs, the hole is shrinking. TEMPO will help scientists track the natural ozone layer on hourly basis throughout the day to assess its strength and its ability to block harmful UV radiation from reaching the surface of the Earth.
Ozone affects the health of both humans and the environment at ground level, as well. For humans, the gas can cause a range of respiratory systems, from chest pain to congestion, and it can worsen pre-existing respiratory conditions such as bronchitis and asthma. Just like how ozone interferes with breathing in humans, it also limits breathing in plants. Notably, it limits the amount of carbon dioxide plants can absorb and the amount of oxygen they can release. This not only damages natural ecosystems; it also reduces crop yield on farms. Repeated studies have shown that higher ozone concentrations in the air lead to lower yields of agricultural crops.
Ozone at ground level cannot form without sunlight, and as a result, ozone levels fluctuate throughout the day and throughout the year in parallel with sunlight levels. For example, ground-level ozone concentrations are often at their highest in the summer months and during the middle of the day when the sun is more directly overhead. Rush-hour traffic can also cause a rise in ozone, as cars release some of its main precursors, nitrogen oxides, through their exhaust pipes. Further, thunderstorms can introduce ozone to the lower atmosphere. They pull ozone down from the stratosphere, moving it from an area where it helps us to an area where it can cause harm. Overall, ozone levels are at their highest when the atmosphere is warm for an extended period. During these periods, ozone levels can reach a high enough level where they can cause throat and lung irritation and aggravate peoples’ asthma and emphysema.
Amid all the factors that cause ozone to form, TEMPO will help scientists identify its largest sources as well as where ozone goes after it is created. Additionally, the public will ultimately be able to view ozone levels on a map, like doppler radar, to determine whether it is safe to go outside.
The Future of Ozone
Air pollution’s effect on our planet is multifaceted. While the world has reduced its use of substances that damage our stratospheric ozone layer, ozone levels at ground level will continue to threaten human health and the balance of our natural ecosystems and farms. By burning greater volumes of fossil fuels, humans are producing more chemicals that lead ozone to form in our lower atmosphere — into the air we breathe. Further, climate change is leading to more natural disasters such as wildfires and more severe weather events that pump greater amounts of ozone into the air.
These ongoing changes, and their impact on life, make it critical for scientists to constantly monitor ozone levels in our atmosphere. The data TEMPO produces will help us understand the impacts of climate change and will help authorities develop more impactful environmental policies aimed at reducing ozone in our lower atmosphere. Furthermore, TEMPO’s data could help better inform the public about air quality to protect their health. Overall, TEMPO will help us understand the factors that affect ozone in the face of industrialization and climate change and help us develop sustainable solutions that keep our communities and our ecosystems stable and healthy for future generations.