Air Pollution 1. Discuss the meteorological effects on pollution dispersion. McGraw-Hill Encyclopedia of Science and Technology Vol.1, 7th ed. 1992. pp. 242-252 - the introduction of natural and artificial gasses into the atm. -most impurities injected on the surface of the earth

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Feb 22, 2014 (3 years and 5 months ago)

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Air Pollution


1. Discuss the meteorological effects on pollution dispersion.


McGraw
-
Hill Encyclopedia of Science and Technology Vol.1, 7th ed. 1992. pp. 242
-
252


-

the introduction of natural and artificial gasses into the atm.

-
most impurities injected

on the surface of the earth

-
lower layer of atm cleanses itself in a few hours or days becuase of rapid verticle mixing


-
rainfall also removes (can be acids rain)


-
upper layer pollution effects ozone

-
typical natural pollution: salt particles from ocean
s, dust or gases from volcanoes

-
typical artificial: waste smokes and gasses

-
aerosols: pollen spores, rust


-
air pollution can affect health, damage vegetation and structures, may cause climate
change


History:

-
began with fire

-
industrial revolution: bur
ning of coal and fossil fuels, compounded by growing
population


3 dangerous air pollution episodes


-
1930 in Meuse Valley in Belgium


-
1948 in Donora, PA


-
1952 in London, England



-
made the British Clean Air Act


Sources:


-
characterized by: natural vs
. antropogenic, stationary vs. moving, also point,
line, area


Types: gaseous, particulate, inorganics and organics, oxidizers and reducers, radioactive
or inert, and thermal


indoor air pollution:


-
radon


-
chemical levels ten time higher than outside


ef
fects


-
human and animals: most info comes fromoccupational health studies



-
effects the respiratory system: clinical, epidemiological, and toxicological



-
based on time of exposure and dose



-
makes eyes water and smart


-
vegetation:acid rain, sulfur di
oxide, hydrogen flouride, nitrogen dioxide, ozone,
and ethylene


-
materials: ferous and nonferous materials ( aluminum, copper, silver, nickel,
zinc), building materials, paint, leather, paper, textiles, dyes, rubber, and ceramics


-
atm: short a
nd long wav
e radiation may have the greatest effect on air quality



-
this may lead to global warming


-
pollution of the stratospehere by aircraft, may break down ozone


-
visabilty and smog: block suns rays and traps heat


Dispersion by weather:


-
wind: can transport

up to 600 miles, depends on direction and speed



-
dilution is inversely proportional to speed


-
verticle: temp normally decrese with heigth



-
more turbulance near the ground



-
gravity waves may occur at 300ft



-
the depth of the turbulent air is calle
d the mixing depth and the
maximnum verticle extent


-
dispesion is the spread of pollutants by atmospheeric turbulance



-
eddys move pollution upward



-
enhanced by structures because they increas turbulance due to friction



-
calm air can speed verticle d
ispersion


-
source effects:



-
plumes are hotter and less dense and tend to vertically migrate



-
denser gas and fall to the ground


Sources:


-
primary
-
straight from the source


-
secondary:chemically combined in ATM


-
photochmeistry: light cause chemcial
reactions



-
can create nitrogen dioxide, ozone and per
-
oxyacetalnitrate (eye irritant)



-
acid rain



-
dissolving of ozone


Control


-
ambient monitoring through sensors


-
source control engineering


-
legislation



-
based on effects on humans, veg,, et al.



-
primary=health, secondary standards proctect against all effects



-
criteria pollutants: lead, carbon monoxide, sulfur dioxide, nitrogen
dioxide, ozone and particles



-
1977 ammendment to Clean Air Act: specific standards for geographical
areas (nation
al parks, or forests)



-
1987, deadline for cities to meet federal standards, 60 counld’t make it



-
1990, reduce sulfer dioxide by 50%, other levels were set for other
chemicals


Air Pollution control:


-
cyclone collectors, wet scrubbers, electrostatic pr
ecipitation, gaseous
contaminants,


-
EPA regualtes evaporative emissions from fuel systems and crankcases, exhause
contaminants: carbon monoxide are regulated by
oxidation catalysts, fuel injection and
combustion chamber design, nitrogen dioxide controlle
d by spark timing, exhast gas
recirc., and reduction catalysts


-
incineration


-
atmosphereic control

Legislation (The Weatehr Almanac, 6th ed, Frank E. Blair editor, Gale research inc 1992
pp232
-
267


-
1967 Air Quality Act



-
state set standards from federa
lly established criteria



-
1970 Clean Air Act Amendment



-
EPA had to make standards to protect health and welfare, national
standards for new facilities, standards for facilities emitting, states to develop plans to
bring air to the standard, new standar
ds for automobiles


-
1977 Ammendmenrts



-
procted areas currently with clean air, new deadlines for meeting
standards, review exisitng standards


-
1990 incentives for companies to use new technology, enlist the help of the
marketplace


Standards

primary: p
rotect public health

secondary: protect public welfare including property and aesthetics


Types of pollutants


TSP
-
total suspended particulate


sulfer dioxide


nitrogen dioxide


ozone


carbon monoxide


lead



Meterological effects


-
Bermuda High traps ozon
e along the east, also from stagnation of the atm


CO comes from cars, examined on 1 and 8 hour intervals



wind speed, wind direction, and amospheric stability(veritcle mixing), local wind patterns
sea and mountains


Comanies can earn credits iof they com
e in under the emission bubble. These credits can
be kept for future projects and evelopment or sold to other companies



http://www
-
nacip.ucsd.edu/NRCAtmosChemCommRpt.pdf


Air pollution is generally studied in terms of immediate local concerns rather tha
n as a long
-
term

“global change” issue. In the coming decades, however, rapid population growth and urbanization
in

many regions of the world, as well as changing climatic conditions, may expand the scope of air
quality

concerns by significantly altering a
tmospheric composition over broad regional and even global
scales.

Ozone and PM are of particular concern because their atmospheric residence times are long
enough to

influence air quality in regions far from their sources and because they also contribute
to climate
change.


The accumulation of pollutants in

the atmosphere can affect climate through direct and indirect contributions to earth’s radiative
balance,

and through chemical reactions that alter the lifetime of certain greenhouse gases. In turn,

met
eorological parameters such as temperature, humidity, and precipitation can affect the
sources,

chemical transformations, transport, and deposition of air pollutants. Our understanding of many
of

these climate
-
chemistry linkages is in its infancy. A better

understanding is needed in order to
make

accurate estimates of future changes in climate and air quality and to evaluate options for
mitigating

harmful changes.


we currently do not have the capacity to observe many important medium
-

and longterm

changes
(that is, changes occurring over the course of years to decades) in the chemistry and

composition of the lower atmosphere. If these observational capabilities are not strengthened, this
will

greatly limit our ability to document the evolution of the atmosp
here in the coming decades.





http://www.healthyhouseinstitute.com/a_933
-
Simple_Steps_to_Healthier_Indoor_Air_


1.



Operate the exhaust fan when bathing
and showering
to limit moisture
build up. Be sure to keep the shower curtain or bathtub sliding door open after bathing
to increase air circulation.

2.



Turn on range hood fans when cooking
to expel contaminants released from
food while cooking. Range ho
ods can also eliminate chemicals such as
carbon
monoxide

which can be released during cooking.


3.



Increase
ventilation

rates
during family gatherings and parties.


4.



Ensure that continuous ventilation is provided
in addition to the
intermittent ventilation systems.

5.



Plan routine maintenan
ce for
HVAC

equipment
to ensure all systems are
working properly and performing as intended.

6.



Change filters as instructed
.


Check, clean, or repla
ce furnace and air filters
regularly as recommended.


Consider installing a "high efficiency particulate" or HEPA
filter for better performance.

7.



Clean the home regularly
to prevent dust, dirt, and pet
-
hair accumulation.
Dust and dirt particles can be
come airborne, creating contaminants in the air.


Regular
cleaning can help to eliminate this potential hazard.

8.



Use safe cleaning products
to avoid emitting dangerous chemicals into the
air.


Many products used to clean can release toxic or irritatin
g chemicals when used.


Select cleaning products that are certified for low levels of chemical emissions.

9.



Purchase low emitting finishes and materials
.


New or recently installed
building materials and furnishings can emit dangerous toxins. Look for
products that
are certified for low chemical emissions.

10.



Ensure that clothes dryers are exhausted directly to the outside
and
make sure that filters and hoods are cleaned regularly to maintain airflow.

11.



Select only those ventilation products wh
ich are HVI Certified


to
ensure your airflow, sound level and energy performance expectations are met.




http://www.walktoschool.org/why/environment.cfm


Ozone can cause these health effect
s:



irritated lung airways



shortness of breath



chest pain



wheezing and coughing



reduced lung function



asthma attacks



damaged lung tissue



chronic respiratory illnesses such as pneumonia and bronchitis

Particulate matter can cause these health effects
:



persistent coughs and phlegm



respiratory and cardiovascular problems



chronic bronchitis



decreased lung function



premature death

Carbon monoxide can cause these health effects:



reduces cardiovascular and central nervous system functions



cardiovascul
ar health effects: chest pain,



central nervous system health effects: vision problems, reduced ability to work or learn, reduced
manual dexterity, and difficulty performing complex tasks. At high levels, can cause death.

Toxic air pollutants can cause th
ese health effects:



damaged immune system



reproductive problems (reduced fertility)



respiratory problems



developmental disorders



nervous system disorders



cancer