8 air polution ozone
TRANSCRIPT
-
7/28/2019 8 Air Polution Ozone
1/19
2/8/13
1
Air PollutionBeijing,chinaJanuary2013
Why we care:
Smog, acid rain, health hazards, global climate change
1. What is air pollution?2. Where does pollution come from?3.Air hazard events and pollution meteorology4.Air pollution and climate change5. The Ozone Hole
Todays Lecture: Air Pollution
-
7/28/2019 8 Air Polution Ozone
2/19
2/8/13
2
Pollution Meteorology
Meteorological conditions can make thepollution issue better or worse
The solution to pollution is dilution Meteorological conditions that inhibit the
dispersion of air pollution will create apollution problem
Air hazard events and pollution meteorology
Topography
At night, cold, dense surface air drainsdownhill into low-lying areas, making them
susceptible to strong temperature
inversions
Hills and mountains can trap air Sea breezes can provide cold air masses
Air hazard events and pollution meteorology
-
7/28/2019 8 Air Polution Ozone
3/19
2/8/13
3
Inversions inhibit vertical convection, trapping pollutants close
to the surface. Strong, persistent, inversions over urban areas
lead to much greater concentrations of pollutants.
Inversions
5 C warmer
Air hazard events and pollution meteorology
Los Angeles smog
29 January 2004.
The top of the
inversion layer is
easily seen against
hills
a thick brown or
slightly orange haze
-inversion is belowthe top of the highest
buildings.
--The exhaust frommore than a million
cars driven in the
morning rush hour istrapped below this
level.
Air hazard events and pollution meteorology
-
7/28/2019 8 Air Polution Ozone
4/19
2/8/13
4
Air hazard events and pollution meteorology
Air hazard events and pollution meteorology
-
7/28/2019 8 Air Polution Ozone
5/19
2/8/13
5
Jan14,2013
Other Meteorological Factors
Sunlight/clear skies increases production of
photochemical smog
Air hazard events and pollution meteorology
Rain will scrub the atmosphere because
many of the pollutants are condensation
nuclei or dissolve easily in water
-
7/28/2019 8 Air Polution Ozone
6/19
2/8/13
6
Air hazard events and pollution meteorology
CloudSeeding
Air hazard events and pollution meteorology
Chinausedcloudseeding
inBeijingjustbeforethe
2008OlympicGamesin
ordertocleartheairof
polluon.
CloudSeeding
-
7/28/2019 8 Air Polution Ozone
7/19
2/8/13
7
InFebruary2009,Chinaalso
blastediodidescksover
Beijingtoarficiallyinduce
snowfallaQerfourmonthsof
drought,andblastediodide
scksoverotherareasof
northernChinatoincrease
snowfall.Thesnowfallin
Beijinglastedforapproximately
threedaysandledtothe
closureof12mainroads
aroundBeijing
CloudSeeding
1. What is air pollution?2. Where does pollution come from?3.Air hazard events and pollution meteorology4.Air pollution and climate change5. The Ozone Hole
Todays Lecture: Air Pollution
-
7/28/2019 8 Air Polution Ozone
8/19
2/8/13
8
Air pollution and climate change
-
7/28/2019 8 Air Polution Ozone
9/19
2/8/13
9
RadiaveBudgetofAerosols
Air pollution and climate change
Mainpoint:MostaerosolsCOOLthesurfacetemperature!
Air pollution and climate change
Anyrolein
global
warming?
-
7/28/2019 8 Air Polution Ozone
10/19
2/8/13
10
Air pollution and climate change
Anyrolein
global
warming?
VanillicAcid
Sourcesofblackcarbon
(soot)?
-
7/28/2019 8 Air Polution Ozone
11/19
2/8/13
11
Air pollution and climate change
Anyrolein
global
warming?
GlobalDimming
Air pollution and climate change
Conceptthathumanaerosolscooledtheclimate,andhelptooffsetglobalwarming.
Thedecreaseofglobaldimmingagentspromoteswarming.
-
7/28/2019 8 Air Polution Ozone
12/19
2/8/13
12
1. What is air pollution?2. Where does pollution come from?3.Air hazard events and pollution meteorology4.Air pollution and climate change5. The Ozone Hole
Todays Lecture: Air Pollution
Darkestblueareas
representregionsof
maximumozone
depleon
1979
19821984 1986
1988 1990
19921994
1997
1999
2004
The Ozone Hole
-
7/28/2019 8 Air Polution Ozone
13/19
2/8/13
13
What is the ozone hole?
Media confuses it with global warming Over the poles (especially Antarctica),
stratospheric ozone depleted over past 30years
Hole presently size Antarctica Ozone (O3) contributes to the greenhouse
effect
And of course O3 creation at the ground levelis bad bad bad.
The Ozone Hole
OzoneintheAtmosphere
The Ozone Hole
90%in
Stratosphere
10%in
Troposphere
recall:
goodup
high,bad
nearby
-
7/28/2019 8 Air Polution Ozone
14/19
2/8/13
14
How is ozone formed?
UVradiaonstrikestheO2moleculeandsplitsit,
atomicoxygenassociatesitselfwithanotherO2
moleculetomakeOzone(O3)
O2+sunlight>O+O
O+O2>O3
The Ozone Hole
The Ozone Hole
Sunburn
DNAdamage(cancer)
NoDamage
-
7/28/2019 8 Air Polution Ozone
15/19
2/8/13
15
Why do we like Ozone?
Too much UV:
Eye damage, cataracts,Skin cancers
photoagingDamage to land species
Damage to aquaticspecies (plankton)
The Ozone Hole
Short answer: it protects us fromUV radiation!
What causes the depletion?
Release of man-made chemicals- CFCs (Chlorofluorocarbons) - refrigerants,aerosol sprays, solvents and foam-blowing agents
- halogen compounds (F, Cl, Br) - Fire fightersused bromine-containing halogens to put out fires
- Nox
The Ozone Hole
-
7/28/2019 8 Air Polution Ozone
16/19
2/8/13
16
The Ozone Hole
Sources that harm ozone layerThe Ozone Hole
-
7/28/2019 8 Air Polution Ozone
17/19
2/8/13
17
One chlorine atom on average - destroys one thousand ozonemolecules before converted into form harmless to ozone
The Ozone Hole
The Ozone Hole
Why over the poles?
Isolatedair
Chemical
breakdownis
favoredincold
airandbypolar
stratosphericclouds
Ozonehole
changesseasonally
-
7/28/2019 8 Air Polution Ozone
18/19
2/8/13
18
Arctic ozone hole?
2004
Antarctic ozone hole?
The Ozone Hole
Why over the poles?
2000
What does this look like on population
density map?
The Ozone Hole
-
7/28/2019 8 Air Polution Ozone
19/19
2/8/13
19
October Antarctic Ozone
Ozoneisnolongerdecreasing(1ststepintherecoveryprocess)
The Ozone Hole
TheFuture?
The Ozone Hole