of art” [2]. The state of air pollution is often
expressed as air quality (AQ). Air quality is a
measure of the concentrations of gaseous pollutants and size, number or mass of particulate matter
(PM). Air quality is typically measured using in
situ monitors that monitor species such as ozone
(O3), particulate matter, nitrogen oxides, and/or
sulfur dioxide.
Why is Regional Air Quality Important?
An awareness of the detrimental effects of air
pollution came to the forefront because of the
catastrophic effects of the “London Smog” episode of 1952 where more than 4,000 people died
[3]. Shortly after this, the Clean Air Act was
passed by the UK Parliament in 1956 to limit
smoke/sulfur dioxide emissions and improve air
quality in the cities. Air quality legislation
evolved from there, mainly in Europe and the
USA, to what it is today. Current air quality legislation is discussed in more detail in section
“Current Air Quality Legislation and Metrics”.
Air quality remains an important topic because
of its impact on human health, ecosystems, and
its interactions with climate change (CC).
Introduction
The Development of Regional Air Quality
Monitoring and Legislation
The state of air pollution is often expressed as air
quality (AQ). Air quality is a measure of the
concentrations of gaseous and aerosol pollutants
in the atmosphere. Human health, ecosystems,
national heritage (e.g., buildings, monuments),
and regional climate are all impacted by air pollution. The implications for human health and ecosystem impacts can range from superficial surface
discoloration of buildings to serious adverse
health effects, such as loss of months to years of
life. These effects are discussed in further detail in
section “Health Effects, Ecosystem Effects, and
Air Quality”. Air pollution and air quality control
measures have implications for climate change,
owing to feedbacks between composition and climate as well as wider atmospheric interactions.
Policies to improve air quality may not always
have positive effects on climate change and vice
versa. Therefore, as we move forward with air
quality and climate regulation, interactions and
feedbacks from air quality and climate change
trade-offs need to be taken into consideration.
Some of these trade-offs are shown in Fig. 1.
The topic as a whole is addressed in section
“Regional Context”.
Air pollution has a history far longer than the
development of contemporary air quality policies.
Ozone, a current air quality problem and significant contributor to urban pollution, was discovered in 1839 by a German chemist, Christian
Fredrich Schönbein. Air pollution from copper
smelting from as far back as Roman times has
been detected in ice-core measurements [2]. The
plentiful use of fossil fuels in industry and home
heating starting in the Middle Ages, latterly in
trains, was the main progenitor of degraded air
quality through to modern times. A number of
extreme air pollution events starting in the late
1800s provided the motivation for modern air
quality regulation. A number of smog episodes
in London from 1878 to 1962 resulted in excess
deaths of hundreds to thousands of people, with
the most extreme and well known of these events
being the “Big Smoke” of early December 1952
that killed upward of 4,000 people [2–4]. Similar
episodes were also recorded in the Meuse Valley,
Belgium in 1930, and Donora, Pennsylvania,
USA in 1948 where smog events resulted in tens
of excess deaths and the illness of thousands of
residents [2]. Around the same time, Los Angeles
was suffering from a different type of smog, this
one photochemical in origin, that arose from the
mixture of ozone, nitrogen oxides, and volatile
organic compounds (VOCs) produced from a
combination of large amounts of vehicle traffic,
sunny weather, and persistent temperature
inversions [4].
These “smog” events, among others, spurred
the development of air quality regulation in the
USA and Europe. The US Air Pollution Control
Act was first passed in 1955, identifying air pollution as a national problem. Further air pollution
legislation followed with the Clean Air Act in
1963 which set emission standards for stationary
sources (e.g., power plants). This was followed by
348
Regional Air Quality
expressed as air quality (AQ). Air quality is a
measure of the concentrations of gaseous pollutants and size, number or mass of particulate matter
(PM). Air quality is typically measured using in
situ monitors that monitor species such as ozone
(O3), particulate matter, nitrogen oxides, and/or
sulfur dioxide.
Why is Regional Air Quality Important?
An awareness of the detrimental effects of air
pollution came to the forefront because of the
catastrophic effects of the “London Smog” episode of 1952 where more than 4,000 people died
[3]. Shortly after this, the Clean Air Act was
passed by the UK Parliament in 1956 to limit
smoke/sulfur dioxide emissions and improve air
quality in the cities. Air quality legislation
evolved from there, mainly in Europe and the
USA, to what it is today. Current air quality legislation is discussed in more detail in section
“Current Air Quality Legislation and Metrics”.
Air quality remains an important topic because
of its impact on human health, ecosystems, and
its interactions with climate change (CC).
Introduction
The Development of Regional Air Quality
Monitoring and Legislation
The state of air pollution is often expressed as air
quality (AQ). Air quality is a measure of the
concentrations of gaseous and aerosol pollutants
in the atmosphere. Human health, ecosystems,
national heritage (e.g., buildings, monuments),
and regional climate are all impacted by air pollution. The implications for human health and ecosystem impacts can range from superficial surface
discoloration of buildings to serious adverse
health effects, such as loss of months to years of
life. These effects are discussed in further detail in
section “Health Effects, Ecosystem Effects, and
Air Quality”. Air pollution and air quality control
measures have implications for climate change,
owing to feedbacks between composition and climate as well as wider atmospheric interactions.
Policies to improve air quality may not always
have positive effects on climate change and vice
versa. Therefore, as we move forward with air
quality and climate regulation, interactions and
feedbacks from air quality and climate change
trade-offs need to be taken into consideration.
Some of these trade-offs are shown in Fig. 1.
The topic as a whole is addressed in section
“Regional Context”.
Air pollution has a history far longer than the
development of contemporary air quality policies.
Ozone, a current air quality problem and significant contributor to urban pollution, was discovered in 1839 by a German chemist, Christian
Fredrich Schönbein. Air pollution from copper
smelting from as far back as Roman times has
been detected in ice-core measurements [2]. The
plentiful use of fossil fuels in industry and home
heating starting in the Middle Ages, latterly in
trains, was the main progenitor of degraded air
quality through to modern times. A number of
extreme air pollution events starting in the late
1800s provided the motivation for modern air
quality regulation. A number of smog episodes
in London from 1878 to 1962 resulted in excess
deaths of hundreds to thousands of people, with
the most extreme and well known of these events
being the “Big Smoke” of early December 1952
that killed upward of 4,000 people [2–4]. Similar
episodes were also recorded in the Meuse Valley,
Belgium in 1930, and Donora, Pennsylvania,
USA in 1948 where smog events resulted in tens
of excess deaths and the illness of thousands of
residents [2]. Around the same time, Los Angeles
was suffering from a different type of smog, this
one photochemical in origin, that arose from the
mixture of ozone, nitrogen oxides, and volatile
organic compounds (VOCs) produced from a
combination of large amounts of vehicle traffic,
sunny weather, and persistent temperature
inversions [4].
These “smog” events, among others, spurred
the development of air quality regulation in the
USA and Europe. The US Air Pollution Control
Act was first passed in 1955, identifying air pollution as a national problem. Further air pollution
legislation followed with the Clean Air Act in
1963 which set emission standards for stationary
sources (e.g., power plants). This was followed by
348
Regional Air Quality