Presentation Slides for
Air Pollution and Global Warming:
History, Science, and Solutions
Chapter 3: Structure and Composition of the PresentDay Atmosphere
By Mark Z. Jacobson
Cambridge University Press (2012)
Last update: January 20, 2012
The photographs shown here either appear in the textbook or were obtained from the
internet and are provided to facilitate their display during course instruction.
Permissions for publication of photographs must be requested from individual
copyright holders. The source of each photograph is given below the figure and/or in
the back of the textbook.
Toricelli's 1643 Experiment With
Mercury Barometer
Le Puy de Dôme, France
www.wired.cz
Edgar Fahs Smith Collection, U. Penn. Library
Toricelli's Experiment With
Mercury Barometer
Example 3.1.
How much mercury balances 1000 hPa of pressure?
p
1000 hPa
100 kg m 1 s 2
h


 0.752 m = 29.6 inches
kg
m
1
hPa
g 13, 558
 9.81
m3
s2
Pressure and Density Versus Altitude
Figure 3.2
Processes Affecting Temperature
Temperature
Proportional to kinetic energy of an air molecule traveling
at its average speed
4
1
kB T  M v a2

2
Conduction
Transfer of energy from molecule to molecule
Convection
Transfer of energy by vertical mass movement of a fluid
Advection
Transfer of energy by horizontal movement of a fluid
Radiation
Energy transferred in the form of electromagnetic waves
Temperature Versus Altitude
Figure 3.3
Daytime and Nighttime
Boundary Layer
Figure 3.4
Atmosphere Up to Thermosphere
www.ucar.edu
Aurora in Thermosphere
lasp.colorado.edu
Altitude (km)
Altitude (km)
Jan/July Temperature vs.
Altitude/Latitude
Latitude (degrees)
Latitude (degrees)
Figure 3.5
Equation of State
Boyle’s Law
p~1/V
(3.3)
Charles’ Law
V ~T
(3.4)
Avogadro’s Law
V~n
(3.5)
Ideal gas law
(3.6)
(simplified equation of state)
p = nR*T/V
= NkBT
Number concentration N = nA/V
Boltzmann’s constant kB = R*/A
Lifting of a parcel of air
Low T, Low P, High V
High T, High P, Low V
Charles Law and Hot Air Balloon
“The country people
who saw it fall were
frightened and attacked
it with stones and
knives so that it was
much mangled” – Ben
Franklin
Montgolfier
Hot Air Balloon
June 4, 1783
www.aps.org
Charles’s
Hydrogen
Balloon
Aug. 27, 1783
www.aps.org
Equation of State
p=NkBT
kB = 1.3807 x 10-19 cm3 hPa K-1
Example 3.4:
Earth’s surface
p
T
----> N
= 1013 hPa
= 288 K
= 2.55 x 1019 molecules cm-3
48 km altitude
p
T
----> N
= 1 hPa
= 270 K
= 2.68 x 1016 molecules cm-3
Dalton’s Law of Partial Pressure
Total air pressure equals sum
of partial pressures of
individual gases in the air.
Edgar Fahs Smith Collection, U. Penn. Library
Equation of State for Dry Air
Total atmospheric pressure
pa = pd+pv
(3.11)
Equation of state for dry air
pd = NdkBT
(3.12)
Volume Mixing Ratio
Xq=Nq/Nd= pq/pd (molecules of gas/molecule of dry air)
1% = 0.01 = 104 ppmv
1 ppmv = 0.000001 = 0.0001% = 1000 ppbv = 106 pptv
Example 3.6:
Ozone
Xq = 0.10 ppmv
T
= 288 K
pd
--N
d
= pd/kBT = 2.55 x 1019 molec. cm-3
--N
q
= XqNd = 2.55 x 1012 molec. cm-3
= 1013 hPa
(3.14)
Composition of the Air
Well-Mixed Gases
Gas
Nitrogen (N2)
Oxygen (O2)
Argon (Ar)
Neon (Ne)
Helium (He)
Krypton (Kr)
Xenon (Xe)
Volume mixing ratio
(percent)
(ppmv)
78.08
780,800
20.95
209,500
0.93
9,300
0.0015
15
0.0005
5
0.0001
1
0.000005
0.05
Table 3.2
Pollutants for Different Problems
Indoor air pollution
Gases: NO2, CO, HCHO, SO2, organic gases, radon
Particles: Black carbon, organic matter, sulfate, nitrate,
ammonium, allergens, asbestos, fungal spores, pollen,
tobacco smoke
Outdoor urban air pollution
Gases: O3, NO, NO2, CO, ethene, toluene, xylene, PAN
Particles: Black carbon, organic matter, sulfate, nitrate,
ammonium, soil dust, sea spray, tire particles, lead
Acid deposition
Gases: SO2, H2SO4, NO2, HNO3, HCl, CO2
Particles: Sulfate, nitrate, chloride
Table 3.4
Pollutants for Different Problems
Stratospheric ozone reduction
Gases: O3, NO, HNO3, HCl, ClONO2, chlorofluorocarbons
Particles: chloride, sulfate, nitrate
Global climate change
Gases: H2O, CO2, CH4, N2O, O3, chlorofluorocarbons
Particles: black carbon, organic matter, sulfate, nitrate,
ammonium, soil dust, sea spray
Table 3.4
Carbon Dioxide [CO2(g)]
Colorless, odorless, greenhouse gas
Sources
Bacterial fermentation, respiration
Plant, animal, fungus, protozoa respiration
Evaporation from the oceans, chemical reaction
Volcanos; biomass, biofuel, fossil-fuel burning
Sinks
Photosynthesis
Autotrophic bacterial respiration
Dissolution into oceans, lakes; transfer to ice caps, soil
Chemical weathering, photolysis in upper atmosphere
Health effects
>15,000 ppmv affect respiration;
> 30,000 ppmv --> headaches, dizziness, nausea
Carbon Storage Reservoirs
Location
Atmosphere
Gas and particle
Surface oceans
Live organic carbon
Dead organic carbon
Bicarbonate ion
Deep oceans
Dead organic carbon
Bicarbonate ion
Ocean sediments
Dead organic carbon
Land/ocean sediments
Carbonate rock
Land
Live organic carbon
Dead organic carbon
GT-C
859
5
30
500
3000
40,000
10,000,000
60,000,000
800
2000
Table 3.7
Carbon Dioxide Aqueous Chemistry
Dissolution/Dissociation
CO2(aq) + H2O(aq)
Dissolved Liquid
carbon dioxide water
(3.15,3.16)
CO2(g)
CO2(aq)
Gaseous
carbon
dioxide
Dissolved
carbon
dioxide
H2CO3(aq)
Dissolved
carbonic acid
H+ + HCO32H+ + CO32Hydrogen Bicarbonate Hydrogen Carbonate
ion
ion
ion
ion
Formation of calcium carbonate
Ca2+ + CO32Calcium Carbonate
ion
ion
(3.17)
CaCO3(s)
Calcium
carbonate
Chemical Weathering
Breakdown and reformation of rocks and minerals at the atomic and
molecular level by chemical reaction
CaSiO 3(s) + CO2(g)
Generic
Carbon
calcium
dioxide
silicate
CaCO3(s) + CO2(g) + H2O(aq)
Calcium Gaseous
Liquid
carbonate
carbon
water
dioxide
CaCO3(s) + SiO2(s)
Calcium
Silicon
carbonate
dioxide
(calcite)
(quartz)
CaCO3(s) + H2CO3(aq)
Calcium Carbonic
carbonate
acid
(3.18)
Ca2+ + 2HCO3Calcium Bicarbonate
ion
ion
(3.19)
Carbon Dioxide Mixing Ratio
Figure 3.11
Instantaneous Data-Constrained Lifetime and
Time-Dependent Anthropogenic Mixing Ratio
of CO2 at a Given Emission Rate
Time-rate-of-change of mixing ratio
dc a ( t )
dt
=E-
c a ( t)
t
Instantaneous data-constrained lifetime (changes with time)
 a t 

E  d a t  dt
Time-dependent anthropogenic and total mixing ratio for a constant emission rate and lifetime
(
c a ( t ) = c a ( 0)e -t / t + tE 1- e -t / t
t  b  a t
)
CO2 Emissions/Mixing Ratio
Data-Constrained Lifetime of CO2
Figure 3.12
Change in CO2 With Current, 390
ppmv, and Zero Emissions

t    b   a 0e t   E 1  e t 


E (2030) ~ 12,800 Tg-C/yr
E (360 ppmv) = 4600 Tg-C/yr
Figure 3.13
1-D Ocean, 2-Box Atmosphere Test
Modeled CO2(g) and Modeled v
Measured Ocean pH 1751-2003
380
360
8.25
340
Data
Model
2
320
8.2
300
8.15
280
1750
1800
1850
1900
1950
8.1
2000
Year
Model: Jacobson (2005); Data: Friedli et al. (1986) and Keeling and Whorf (2003)
Surface ocean pH
CO2(g)
CO mixing ratio (ppmv)
8.3
Surface ocean pH
mixing ratio (ppmv)
pH-500Tg-C/yBBemis
Modeled Ocean Profiles 2004 and
2104 Assuming A1B Future Emissions
Depth (m)
Depth (m)
0
500
1000
(a)
1500
2004
2104
2000
7.8
7.9
8
pH
8.1
8.2
Carbon Monoxide
www.boatingsidekicks .com
www.salem-news.com
U.S. Emission Trends
Figure 3.14
Ozone [O3(g)]
Smell > 20 ppbv; clear at low and faint purple at high mixing ratio
Source
Atmospheric chemical reaction
Sinks
Atmospheric chemical reaction and photolysis
Dissolution into oceans, lakes; transfer to ice caps, soil
Mixing ratios
20-40 ppbv clean air; 40-500 ppbv pollution; 10 ppmv strat.
Health effects
>150 ppbv --> headache
>250 ppbv --> chest pain, sore throat, cough, short breath
Affects vegetation, rubber, textile, dyes, fibers
Ozone
www.nine-patch.com
Schoenbein Color Scale  Increasing Ozone
Teachertech.rice.edu
Nitrogen Dioxide
>80 ppbv: sore throat
150-250 ppbv typical for polluted air
300-800 ppbv reduced lung capacity
> 150 ppmv death
Sulfur Dioxide
1-30 ppbv: typical for polluted air
>300 ppbv: taste
>500 ppbv: odor
>1500 ppbv: bronchial restrictions
> 40,000 ppbv: death
z.about.com
Volcanoes.usgs.gov
Wwwimage.cbsnews.com
Methane [CH4(g)]
Greenhouse gas, long lifetime, produces tropospheric ozone
Sources
Methanogenic bacteria
Natural gas leaks
Biomass, biofuel, fossil-fuel combustion
Atmospheric chemical reaction
Sinks
Methanotrophic bacteria
Atmospheric chemical reaction
Dissolution into oceans, lakes; transfer to ice caps, soil
Health effects
None at ambient mixing ratios
Rice Paddy in Sapa, Vietnam
Juliengrondin/Dreamstime.com
Distribution of PM in Airways
Cormier: www.ehponline.org
All PM enter nose/mouth. PM10 passes larynx to trachea
and bronchial regions. PM2.5 and PM0.1 enter alveoli.
Air Pollution in Lungs
http://www.sciencephoto.com/image/88071/530wm/C0023802-Lung,_post-mortem-SPL.jpg
Air Pollution in Lungs
http://raps.bur.st/20010427/lung-city.jpg
Asbestos in Lungs
http://www.home-air-purifier-expert.com/images/asbestos-in-lungs.jpg
Lead [Pb(s)]
Gray-white solid heavy metal
Sources
Crustal physical weathering
Leaded fuel combustion, lead-acid battery manufacturing
Lead ore crushing and smelting
Dust from soils contaminated with lead-based paint
Solid waste disposal
Sinks
Deposition to oceans, ice caps, soils
Inhalation
Health effects
Lead poisoning: mental retardation, neurological impairment
Plumbism: abdominal pains, black line in gums, paralysis,
blindness, deafness, coma, death
Health Effects of Lead
"We can take example by the workers in lead who have
complexions affected by pallor. For when, in casting, the lead
receives the current of air, the fumes from it occupy the members
of the body, and burning them thereon, rob the limbs of the virtues
of the blood. Therefore it seems that water should not be brought in
lead pipes if we desire to have it wholesome."
Marcus Vitruvius Pollio, Roman engineer, first-century B. C.
Thomas Midgley (1889-1944)
Edgar Fahs Smith Collection, U. Penn. Library
Thomas Midgley
1916: Joined Dayton Eng. Laboratory Companies (DELCO)
1919: DELCO main research lab for General Motors (GM)
1921: Invented leaded gasoline, which he named Ethyl
Lead reduced knock, increased power to vehicles
1923: VP of Ethyl Gas. Co., a GM and Standard Oil subsidiary
1923: Midgley suffered lead poisoning, but he defended lead:
"The exhaust does not contain enough lead to worry about, but no
one knows what legislation might come into existence fostered by
competition and fanatical health cranks.”
Thomas Midgley
1923-5: 17 workers died, 149 injured due to lead poisoning
1924: 5 of the workers became suddenly insane from poisoning
1925: Despite working on ethanol/benzene blends, iron carbonyl
alternatives, Midgley countered,
"...tetraethyl lead is the only material available which can bring about
these (antiknock) results, which are of vital importance to the
continued economic use by the general public of all automotive
equipment, and unless a grave and inescapable hazard exists in the
manufacture of tetraethyl lead, its abandonment cannot be justified"
1924: Forced to step down as VP due to managerial problems
1924: Returned to research on synthetic rubber in Dayton for GM
1925: U.S. Surgeon General organized committee to investigate lead
Observed drivers/garage workers did not experience poisoning
--> “no grounds for prohibiting the use of Ethyl gasoline.”
Leaded Gasoline
1930s: 90 percent of vehicles leaded
1936: Federal Trade Commission
"...entirely safe to the health of (motorists) and to the public in
general when used as a motor fuel, and is not a narcotic in its effect, a
poisonous dope, or dangerous to the life or health of a customer,
purchaser, user or the general public."
1959: U.S. Public Health Service
"...regrettable that the investigations recommended by the Surgeon
General's Committee in 1926 were not carried out by the Public
Health Service."
1975: Catalytic converter invented; lead deactivates catalyst
1977: Lead regulated as criteria air pollutant in the U.S.