This document discusses photochemical smog in Los Angeles. It notes that photochemical smog is caused by three main ingredients: high automobile traffic, plenty of sunlight, and a stable atmosphere. It describes the chemical reactions that cause smog formation and notes that weather conditions, such as high pressure systems, can lead to air stagnation and worse air quality. The document discusses how California has implemented emission controls like catalytic converters and carpool lanes to reduce automobile emissions and improve air quality. However, it notes that traffic volume remains a major challenge and improving public transportation is needed.
Using Visibility Analyses As An Alternative Approach To Regulate Air Quality BREEZE Software
This paper will examine the U.S. experience in modeling visibility impairment and to shed some light on the potential application of similar concepts in other countries.
Many forms of atmospheric pollution affect human health
and the environment at levels from local to global. These
contaminants are emitted from diverse sources, and some
of them react together to form new compounds in the air.
Industrialized nations have made important progress toward controlling some pollutants in recent decades, but air quality is much worse in many developing countries, and global circulation patterns can transport some types of pollution rapidly around the world. In this unit, discover the basic chemistry of atmospheric pollution and learn which human activities have the greatest impacts on air quality.
Air and Air PollutionChapter 8Long-Distanc.docxnettletondevon
Air and Air Pollution
Chapter 8
Long-Distance Transport of Air Pollution
Global Distillation Effect:Chemicals enter the atmosphere in warm regions and are moved to cooler areas.Yukon, Northern CanadaChemicals concentrate (bioaccumulate) in the body fat of animals at the top of the food chainA single bite of whale skin contains more PCBs than what is safe to consume in one weekBreast milk of Inuit women (where whale is part of the diet) has 5 times more PCB than in women in Southern Canada
*
Long-Distance Transport of Air Pollution
Atmospheric conditions blow pollution from Asia to America across the Pacific OceanMany countries have policies and regulations to limit pollution from being transported
*
Long-Distance Transport of Air Pollution
*
Learning Objectives:
Define atmosphere and list the major gases comprising the atmosphere
Briefly describe the four major concentric layers of the atmosphere
Define Coriolis effect
The Atmosphere
*
The AtmosphereAtmosphere Gaseous envelope surrounding the EarthOxygen and Nitrogen = 99% of dry airOther gases = 1%Water and traces of air pollutantsFour concentric layers:
Troposphere
Stratosphere
Mesosphere
Thermosphere
*
The Atmosphere
*
The Atmosphere
*
Environmental InSight
*
The AtmosphereAtmosphereEcosystem Services:Protects Earth from UV radiation, x-rays, cosmic raysKeeps Earth’s temperature within living rangeOrganisms depend on the atmosphereOrganism modify and balance the atmospherePhotosynthesisRespiration
*
The AtmosphereAtmospheric CirculationGlobal Circulation PatternsDifferences in air temperatures drive circulationHot air near Equator expands and risesAs it rises, it cools and sinks againConvection process causes air currents that mix warmer and cooler parts of the atmospheremoderates temperatures over Earth’s surfaceWinds Smaller-scale horizontal movementsFluctuations in atmospheric pressuresPlanet’s rotation
*
The Atmosphere
*
The AtmosphereWindSmaller-scale horizontal movementsFluctuations in atmospheric pressuresAir pressure is variable depending on altitude, temperature, and humidityWinds blow from areas of high pressure to areas of low pressure The bigger the difference between the high and low pressures, the stronger the windsPlanet’s rotationCoriolis effectPrevailing WindsPolar EasterliesWesterliesTrade Winds
*
The Atmosphere
*
Global Climate Change
What gases make up the atmosphere?
What two layers of the atmosphere are closest to Earth’s surface? How do they differ from one another?
What is the Coriolis effect, and how does it influence atmospheric circulation?
Types and Sources of Air PollutionLearning Objectives
Define air pollution and distinguish between primary and secondary air pollutants
List the seven major classes of air pollutants and describe their characteristics and sources
*
Air Pollution:Various chemicals (gases, liquids, solids) present in the atmosphere in high enough leve.
Greenhouse Effect Essay
How Does The Greenhouse Effect The Environment?
The Greenhouse Effect On Earth
The Greenhouse Effect And Climate Change
Essay On Greenhouse Gases
Essay about Climate Change and Greenhouse Gases
Climate Change and Greenhouse Gases Essay
Persuasive Essay On Green House Effect
Global Warming and the Greenhouse Effect Essay
The Greenhouse Effect On The Environment
Global Warming and Climate Change Essay
Causes Of The Greenhouse Effect
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The Greenhouse Effect Essay
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Greenhouse Effect Essay
ACID RAIN, THEIR IMPACTS AND BIOTECHNOLOGICAL APPROACHES FOR MANAGEMENTAmbika Prajapati
Acid rain is one of the major environmental threats since 19th century. The effect of acidification has been sighted all over the world such as deleterious ecological effects such as reduced reproduction of aquatic fish species, dieback and stunted growth in plants, accumulation of toxic aluminium and heavy metals in soil and water bodies, biodiversity loss including corals and shellfish, degrade to the manmade structures made up of marble and stone and corrosion of metal structures.
The term acid rain was coined in 1852 by Scottish chemist Robert Angus Smith, according to the Royal Society of Chemistry, which calls him the "father of acid rain."
AIR, NOISE, AND RADIATION - MooreLIVING WITH THE EARTHCH.docxdaniahendric
AIR, NOISE, AND RADIATION - Moore
LIVING WITH THE EARTH
CHAPTER 10
AIR, NOISE, AND RADIATION
AIR, NOISE, AND RADIATION - Moore
Objectives for this Chapter
A student reading this chapter will be able to:
1. List and explain the reasons why air pollution is considered a national and global threat.
2. Discuss and describe the chemical and physical components of the atmosphere, and explain the mechanisms of dispersion.
AIR, NOISE, AND RADIATION - Moore
Objectives for this Chapter
A student reading this chapter will be able to:
3. Describe the regulatory efforts in the U.S. with emphasis on titles of the 1990 CAAA.
4. Discuss the issues behind stratospheric ozone depletion and global warming.
5. List and discuss the nature, sources, and health and welfare effects of the criteria pollutants.
AIR, NOISE, AND RADIATION - Moore
Objectives for this Chapter
A student reading this chapter will be able to:
6. List, discuss, and describe the major sources of indoor air pollution, including health effects and methods of control.
7. Define noise pollution and radiation. List the major sources and known health effects of noise and radiation.
AIR, NOISE, AND RADIATION - Moore
AIR NOISE AND RADIATION
Introduction
History
Edward I and II of Great Britain severely punished air polluters
Until 1930s (Meuse Valley, Belgium.) air pollution considered a nuisance.
Air pollution episodes in Donora, PA, London England, Losa Angeles, CA, NY City caused many deaths, raised public awareness.
AIR, NOISE, AND RADIATION - Moore
AIR NOISE AND RADIATION
Air pollution threatens global ecology
Consensus grows that industrial emissions such as carbon dioxide and other greenhouse gases, are contributing to global warming .
Chlorofluorocarbons may be depleting stratospheric ozone
Acid deposition
AIR, NOISE, AND RADIATION - Moore
AIR NOISE AND RADIATION
Air pollution threatens human health
asthma, bronchitis, emphysema, cancer, respiratory infections, irritation, cardiovascular disease
Air pollution threatens living plants and human-made structures
forest decline, corrosion of metal, soiling of buildings, degradation of paints, textiles, leather, paper, and dyes.
AIR, NOISE, AND RADIATION - Moore
THE ATMOSPHERE AND METHODS OF DISPERSION
Chemical Characteristics
Nitrogen (N2) represents a constant 78 percent of the 500 billion tons of air surrounding the planet, while oxygen (O2) remains steady at 21 percent, and argon (Ar) at 0.9 percent. (Fig. 10-1).
AIR, NOISE, AND RADIATION - Moore
Fig. 10-1
AIR, NOISE, AND RADIATION - Moore
Chemical Characteristics
Human technology and explosive populations could potentially alter the atmospheric balance of gases causing changes in the earth-atmosphere system that jeopardizes our sustainability.
AIR, NOISE, AND RADIATION - Moore
Physical Characteristics
Solar Radiation
The life on earth requires a continuing source of energy.
More than 99 percent of the energy from the s ...
Climate Change All over the World .pptxsairaanwer024
Climate change refers to significant and lasting changes in the average weather patterns over periods ranging from decades to millions of years. It encompasses both global warming driven by human emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. While climate change is a natural phenomenon, human activities, particularly since the Industrial Revolution, have accelerated its pace and intensity
Using Visibility Analyses As An Alternative Approach To Regulate Air Quality BREEZE Software
This paper will examine the U.S. experience in modeling visibility impairment and to shed some light on the potential application of similar concepts in other countries.
Many forms of atmospheric pollution affect human health
and the environment at levels from local to global. These
contaminants are emitted from diverse sources, and some
of them react together to form new compounds in the air.
Industrialized nations have made important progress toward controlling some pollutants in recent decades, but air quality is much worse in many developing countries, and global circulation patterns can transport some types of pollution rapidly around the world. In this unit, discover the basic chemistry of atmospheric pollution and learn which human activities have the greatest impacts on air quality.
Air and Air PollutionChapter 8Long-Distanc.docxnettletondevon
Air and Air Pollution
Chapter 8
Long-Distance Transport of Air Pollution
Global Distillation Effect:Chemicals enter the atmosphere in warm regions and are moved to cooler areas.Yukon, Northern CanadaChemicals concentrate (bioaccumulate) in the body fat of animals at the top of the food chainA single bite of whale skin contains more PCBs than what is safe to consume in one weekBreast milk of Inuit women (where whale is part of the diet) has 5 times more PCB than in women in Southern Canada
*
Long-Distance Transport of Air Pollution
Atmospheric conditions blow pollution from Asia to America across the Pacific OceanMany countries have policies and regulations to limit pollution from being transported
*
Long-Distance Transport of Air Pollution
*
Learning Objectives:
Define atmosphere and list the major gases comprising the atmosphere
Briefly describe the four major concentric layers of the atmosphere
Define Coriolis effect
The Atmosphere
*
The AtmosphereAtmosphere Gaseous envelope surrounding the EarthOxygen and Nitrogen = 99% of dry airOther gases = 1%Water and traces of air pollutantsFour concentric layers:
Troposphere
Stratosphere
Mesosphere
Thermosphere
*
The Atmosphere
*
The Atmosphere
*
Environmental InSight
*
The AtmosphereAtmosphereEcosystem Services:Protects Earth from UV radiation, x-rays, cosmic raysKeeps Earth’s temperature within living rangeOrganisms depend on the atmosphereOrganism modify and balance the atmospherePhotosynthesisRespiration
*
The AtmosphereAtmospheric CirculationGlobal Circulation PatternsDifferences in air temperatures drive circulationHot air near Equator expands and risesAs it rises, it cools and sinks againConvection process causes air currents that mix warmer and cooler parts of the atmospheremoderates temperatures over Earth’s surfaceWinds Smaller-scale horizontal movementsFluctuations in atmospheric pressuresPlanet’s rotation
*
The Atmosphere
*
The AtmosphereWindSmaller-scale horizontal movementsFluctuations in atmospheric pressuresAir pressure is variable depending on altitude, temperature, and humidityWinds blow from areas of high pressure to areas of low pressure The bigger the difference between the high and low pressures, the stronger the windsPlanet’s rotationCoriolis effectPrevailing WindsPolar EasterliesWesterliesTrade Winds
*
The Atmosphere
*
Global Climate Change
What gases make up the atmosphere?
What two layers of the atmosphere are closest to Earth’s surface? How do they differ from one another?
What is the Coriolis effect, and how does it influence atmospheric circulation?
Types and Sources of Air PollutionLearning Objectives
Define air pollution and distinguish between primary and secondary air pollutants
List the seven major classes of air pollutants and describe their characteristics and sources
*
Air Pollution:Various chemicals (gases, liquids, solids) present in the atmosphere in high enough leve.
Greenhouse Effect Essay
How Does The Greenhouse Effect The Environment?
The Greenhouse Effect On Earth
The Greenhouse Effect And Climate Change
Essay On Greenhouse Gases
Essay about Climate Change and Greenhouse Gases
Climate Change and Greenhouse Gases Essay
Persuasive Essay On Green House Effect
Global Warming and the Greenhouse Effect Essay
The Greenhouse Effect On The Environment
Global Warming and Climate Change Essay
Causes Of The Greenhouse Effect
Persuasive Essay: The Greenhouse Effect
The Greenhouse Effect Essay
Climate Control And The Greenhouse Effect
The Enhanced Green House Effect Essay example
Greenhouse Effect Essay
ACID RAIN, THEIR IMPACTS AND BIOTECHNOLOGICAL APPROACHES FOR MANAGEMENTAmbika Prajapati
Acid rain is one of the major environmental threats since 19th century. The effect of acidification has been sighted all over the world such as deleterious ecological effects such as reduced reproduction of aquatic fish species, dieback and stunted growth in plants, accumulation of toxic aluminium and heavy metals in soil and water bodies, biodiversity loss including corals and shellfish, degrade to the manmade structures made up of marble and stone and corrosion of metal structures.
The term acid rain was coined in 1852 by Scottish chemist Robert Angus Smith, according to the Royal Society of Chemistry, which calls him the "father of acid rain."
AIR, NOISE, AND RADIATION - MooreLIVING WITH THE EARTHCH.docxdaniahendric
AIR, NOISE, AND RADIATION - Moore
LIVING WITH THE EARTH
CHAPTER 10
AIR, NOISE, AND RADIATION
AIR, NOISE, AND RADIATION - Moore
Objectives for this Chapter
A student reading this chapter will be able to:
1. List and explain the reasons why air pollution is considered a national and global threat.
2. Discuss and describe the chemical and physical components of the atmosphere, and explain the mechanisms of dispersion.
AIR, NOISE, AND RADIATION - Moore
Objectives for this Chapter
A student reading this chapter will be able to:
3. Describe the regulatory efforts in the U.S. with emphasis on titles of the 1990 CAAA.
4. Discuss the issues behind stratospheric ozone depletion and global warming.
5. List and discuss the nature, sources, and health and welfare effects of the criteria pollutants.
AIR, NOISE, AND RADIATION - Moore
Objectives for this Chapter
A student reading this chapter will be able to:
6. List, discuss, and describe the major sources of indoor air pollution, including health effects and methods of control.
7. Define noise pollution and radiation. List the major sources and known health effects of noise and radiation.
AIR, NOISE, AND RADIATION - Moore
AIR NOISE AND RADIATION
Introduction
History
Edward I and II of Great Britain severely punished air polluters
Until 1930s (Meuse Valley, Belgium.) air pollution considered a nuisance.
Air pollution episodes in Donora, PA, London England, Losa Angeles, CA, NY City caused many deaths, raised public awareness.
AIR, NOISE, AND RADIATION - Moore
AIR NOISE AND RADIATION
Air pollution threatens global ecology
Consensus grows that industrial emissions such as carbon dioxide and other greenhouse gases, are contributing to global warming .
Chlorofluorocarbons may be depleting stratospheric ozone
Acid deposition
AIR, NOISE, AND RADIATION - Moore
AIR NOISE AND RADIATION
Air pollution threatens human health
asthma, bronchitis, emphysema, cancer, respiratory infections, irritation, cardiovascular disease
Air pollution threatens living plants and human-made structures
forest decline, corrosion of metal, soiling of buildings, degradation of paints, textiles, leather, paper, and dyes.
AIR, NOISE, AND RADIATION - Moore
THE ATMOSPHERE AND METHODS OF DISPERSION
Chemical Characteristics
Nitrogen (N2) represents a constant 78 percent of the 500 billion tons of air surrounding the planet, while oxygen (O2) remains steady at 21 percent, and argon (Ar) at 0.9 percent. (Fig. 10-1).
AIR, NOISE, AND RADIATION - Moore
Fig. 10-1
AIR, NOISE, AND RADIATION - Moore
Chemical Characteristics
Human technology and explosive populations could potentially alter the atmospheric balance of gases causing changes in the earth-atmosphere system that jeopardizes our sustainability.
AIR, NOISE, AND RADIATION - Moore
Physical Characteristics
Solar Radiation
The life on earth requires a continuing source of energy.
More than 99 percent of the energy from the s ...
Climate Change All over the World .pptxsairaanwer024
Climate change refers to significant and lasting changes in the average weather patterns over periods ranging from decades to millions of years. It encompasses both global warming driven by human emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. While climate change is a natural phenomenon, human activities, particularly since the Industrial Revolution, have accelerated its pace and intensity
Artificial Reefs by Kuddle Life Foundation - May 2024punit537210
Situated in Pondicherry, India, Kuddle Life Foundation is a charitable, non-profit and non-governmental organization (NGO) dedicated to improving the living standards of coastal communities and simultaneously placing a strong emphasis on the protection of marine ecosystems.
One of the key areas we work in is Artificial Reefs. This presentation captures our journey so far and our learnings. We hope you get as excited about marine conservation and artificial reefs as we are.
Please visit our website: https://kuddlelife.org
Our Instagram channel:
@kuddlelifefoundation
Our Linkedin Page:
https://www.linkedin.com/company/kuddlelifefoundation/
and write to us if you have any questions:
info@kuddlelife.org
Epcon is One of the World's leading Manufacturing Companies.EpconLP
Epcon is One of the World's leading Manufacturing Companies. With over 4000 installations worldwide, EPCON has been pioneering new techniques since 1977 that have become industry standards now. Founded in 1977, Epcon has grown from a one-man operation to a global leader in developing and manufacturing innovative air pollution control technology and industrial heating equipment.
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"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...MMariSelvam4
The carbon cycle is a critical component of Earth's environmental system, governing the movement and transformation of carbon through various reservoirs, including the atmosphere, oceans, soil, and living organisms. This complex cycle involves several key processes such as photosynthesis, respiration, decomposition, and carbon sequestration, each contributing to the regulation of carbon levels on the planet.
Human activities, particularly fossil fuel combustion and deforestation, have significantly altered the natural carbon cycle, leading to increased atmospheric carbon dioxide concentrations and driving climate change. Understanding the intricacies of the carbon cycle is essential for assessing the impacts of these changes and developing effective mitigation strategies.
By studying the carbon cycle, scientists can identify carbon sources and sinks, measure carbon fluxes, and predict future trends. This knowledge is crucial for crafting policies aimed at reducing carbon emissions, enhancing carbon storage, and promoting sustainable practices. The carbon cycle's interplay with climate systems, ecosystems, and human activities underscores its importance in maintaining a stable and healthy planet.
In-depth exploration of the carbon cycle reveals the delicate balance required to sustain life and the urgent need to address anthropogenic influences. Through research, education, and policy, we can work towards restoring equilibrium in the carbon cycle and ensuring a sustainable future for generations to come.
WRI’s brand new “Food Service Playbook for Promoting Sustainable Food Choices” gives food service operators the very latest strategies for creating dining environments that empower consumers to choose sustainable, plant-rich dishes. This research builds off our first guide for food service, now with industry experience and insights from nearly 350 academic trials.
Top 8 Strategies for Effective Sustainable Waste Management.pdfJhon Wick
Discover top strategies for effective sustainable waste management, including product removal and product destruction. Learn how to reduce, reuse, recycle, compost, implement waste segregation, and explore innovative technologies for a greener future.
9. Photochemical Smog
The Case of Los Angeles Air Quality
■ Three main ingredients of photochemical smog:
◆ high automobile traffic volume
◆ plenty of sunlight
◆ very stable atmosphere
■ Eastern Pacific High –
◆ Subsidence produces inversion, resulting in an absolutely stable
condition.
◆ Subsidence also produces clear condition and hence more sunlight.
■ Topography – basin helps trapping pollutants
10.
11.
12.
13.
14. Chemical Reactions of Smog
A few important reactions:
(1) NO2 + hν (photon) 🡪 NO + O (hν represents a photon)
fast (2) O + O2 + M 🡪 O3 + M (M represents a neutral
molecule)
(3) O3 + NO 🡪 NO2 + O2
(4) O + HC (hydrocarbon)🡪 S.P. (stable product) + F.R. (free
radical)
slow (5) O3 + HC 🡪 S.P. + F.R.
(6) F.R. + HC 🡪 S.P. + F.R.
(Being a stable product doesn’t mean it is pleasant! It can be irritating to
our body.)
(7) F.R. + NO 🡪 F.R. + NO2
fast (8) F.R. + NO2 🡪 Stable Product (PAN-Type,
Peroxyacetyl Nitrate )
(9) F.R. + F.R. 🡪 Stable product
15.
16. You can tell the air stability by watching the
motion of the chimney smoke
18. Photochemical Smog and Weather
■ Whereas the photochemistry produces smog, the severity of smog
pollution is largely controlled by the weather conditions.
■ In a local scale, the air stability controls the pollution as we described
above. In a larger scale sense, it is the weather systems that determine
the air stability.
■ The following slides show the close relationship between the air
quality and meteorological conditions.
19. •Surface high – sinking air, dry, clear, stable air, may
cause upper level inversion
•Surface low – rising air, cloudy or rainy, unstable air
21. We see that there was a low pressure system out in the Pacific . The whole
California was controlled by a high pressure system. Near Southern California, the
weather was clear and the air was stable. This usually implies that air quality
would be poor.
Saturday
22. We can use the ozone level s a general air quality index. On this day, the
peak ozone level at Pasadena was nearly 200 units while it was about 80
units in West LA. High ozone level indicates poor air quality.
23. Look at the remarkable improvement of ozone levels at Pasadena and W.
LA! The above series of slides show clearly the intimate relation between
local air quality and weather.
26. During the life cycle of plants, some organic particles (such as turpanoids)
are ejected. Due to the high frequency of air stagnation these particles tend
to stay in the air for a long time and hence the hazy look. This is of course a
natural phenomenon and not a man-made pollution, but it is another good
example of the close relation between particle concentration and weather.
Source: National Park Service
27.
28.
29.
30. Emission Control
■ Because of the photochemical smog problem and its relation with
automobile emissions, California has enacted a series of regulations
purported to cut down the emissions.
■ Two specific actions are of interest in this regard:
◆ (1) The installation of catalytic converter to reduce then amount of
NOX emitted.
◆ (2) The designation of ‘diamond lanes’— only cars with two or
more passengers can use these lanes, so as to encourage
carpooling.
■ The problem, however, will stay as long as the traffic volume is large.
One really needs to develop an efficient public transportation system in
a city like that.
31. Vacuum-Insulated Automotive Catalytic
Converter
Variable-conductance vacuum
insulation and phase change
material (heat storage) are used to
keep catalytic converters hot for
up to 24 hours.
By having a hot (> 250oC)
converter at the start of a trip,
auto emissions can be reduced by
up to 80%.
NREL developed and patented this
concept, and has worked with
Benteler Industries of Grand
Rapids, Mich., to commercialize it
under a Cooperative Research and
Development Agreement
(CRADA).
Converter Basics:
Three main ingredients of photochemical smog: high automobile traffic volume, plenty of sunlight, and very stable atmosphere.
One example of the locations that have all three necessary ingredients is the Los Angeles Basin.
Due to the lack of efficient public transportation, residents there depend on their cars. The traffic jam there is no news at all.
Los Angeles’ climate is dominated by the Eastern Pacific High – the subsidence above produces compression heating of the air, and the temperature is often higher at a few hundred feet level than at surface – an inversion condition. This is of course an absolutely stable condition.
The subsidence not only produces inversion but also clear air. It is hard to form clouds and rain due to the weak vertical motion. Thus sky is clear most of the time—a lot of sunshine!(That’s why Hollywood is a good place for making movies!)
The topography of Los Angeles – a basin also helps to trap air pollutants.
Thus there is no surprise that photochemical smog can be very severe in LA.
There are many chemical reactions involved in producing the photochemical smog. We only list a few important ones (note the chemical symbols used here are not necessary exact, some are ‘descriptive’ only):
(1) NO2 + hν 🡪 NO + O (hν represents a photon)
fast (2) O + O2 + M 🡪 O3 + M (M represents a neutral molecule)
(3) O3 + NO 🡪 NO2 + O2
(4) O + HC (hydrocarbon)🡪 stable product + F.R. (free radical)
slow (5) O3 + HC 🡪 S.P. + F.R.
(6) F.R. + HC 🡪 S.P. + F.R.
(Being a stable product doesn’t mean it is pleasant! It can be irritating to our body.)
(7) F.R. + NO 🡪 F.R. + NO2
fast (8) F.R. + NO2 🡪 Stable Product (PAN-Type, Peroxyacetyl Nitrate )
(9) F.R. + F.R. 🡪 Stable product
For our purpose here, the most important reactions are (1)-(3).
As explained before, the severity of smog problem is closely related to weather condition. The inversion layer that traps air pollutants in Los Angeles is caused by the subsidence in the Eastern Pacific High.
Eastern Pacific High is a semi-permanent high pressure system that dominates the weather pattern of southern California most of the time. It is one of the ‘subtropical high pressure systems’.
If the influence of this high pressure system decreases (for example, if a low pressure system moves in), then this inversion layer may disappear and the air quality improves.
The following slides illustrate the above-said weather-air quality relation . They are taken from Los Angeles Times in 1988.
Because clouds usually form in ascending air, they often appear in low pressure regions.This often accompanied by rain, snow, or thunderstorms. In contrast, high pressure regions are often sunny and calm. In summer, this could mean clear but hot weather. In winter, this could mean extremely cold weather (as is often the case for Wisconsin).
We can use the ozone level s a general air quality index. On this day, the peak ozone level at Pasadena was nearly 200 units while it was about 80 units in West LA. High ozone level indicates poor air quality. Air quality in W. LA is generally better than that in Pasadena because it is next to the ocean and a small scale circulation –the sea breeze - helps to vent air pollutants out.
Sea breeze is a wind phenomenon caused by the difference of heating over land and ocean. During the daytime, it is usually warmer over land than over the ocean. The temperature difference causes a pressure difference that in turn causes a wind that blows from the sea towards the land. In the night, the situation is reversed and the wind blows from the land towards the ocean.
So it appears that high pressure systems tend to cause more severe local air quality problems due to their characteristic weak wind condition- called air stagnation. The frequency of air stagnation is a useful index of local air quality.
One example of air stagnation frequency distribution in the eastern half of US is shown in the figure here.
We see the highest frequency occurs in the bordering region between Tennessee and Georgia . Do you know any special phenomena relevant to the air quality there?
The Great Smokies got its name from the often hazy appearance in the mountain valleys there. Why is it so? Remember that this is a densely forested region. During the life cycle of plants, some organic particles (such as turpanoids) are ejected. Due to the high frequency of air stagnation these particles tend to stay in the air for a long time and hence the hazy look. This is of course a natural phenomenon and not a man-made pollution, but it is another good example of the close relation between particle concentration and weather.