Ozone in the Tropospher Changes in the Environme Nain Singh
Jan 15, 2016
Ozone in the Troposphere
Changes in the Environment
Nain Singh
Let’s begin with definition.….• Ozone - colorless, odorless gas with 3
oxygen atoms (O3)
• Pollutant - a substance that affects air, water, or other natural resources.
• Ozone hole - a region in the atmosphere in where the ozone layer has less than normal concentration of ozone.
OxygenOzone
Composition of Atmosphere
• Nitrogen 78%• Oxygen 21%• Argon 0.93%
• Other gases traces ( O3, CO2, CFCs)
The Thin Blue Veil of the Earth’s Atmosphere
The thin blue veil that shields the atmosphere.
What is the difference between
Troposphere & Stratosphere?
Troposphere vs. Stratosphere
Troposphere is the layer in
the atmosphere from the
earth’s surface to a height
of 10 miles above
Stratosphere extends
from the top of
troposphere to 100 mi
Where is ozone found?
Stratosphere
(15-21mi
)
Troposphere
(0-10mi )
10-30ppb
1000xppb
Primary pollutants emitted:
• Nitrogen Oxides (NOX)
• VOC’sa
aPrecursors of ozone
• Particulate Matter• Sulfur Dioxide• Carbon Dioxide• Lead
•a
EPA- harmful to health
• NC ranked 2nd in the US
in unhealthy ozone levels
How have humans polluted the air?
Emission of hydrocarbon in the US 1983
Petrochemical38%
Electric Utilities
0%
Automobiles36%
Industrial fuel 11%
Other15% Petrochemical
Electric Utilities
Automobiles
Industrial fuel
Other
Anthropogenic Sources
It’s the CFC’s!
O3 uv O + O 2
O + O3 uv 2O2
Net Loss: 2O3 = 3O2
Ozone layer in the stratosphere protects the earth
from the sun’s UV light
In Troposphere• Bad ozone• Harmful increase
Concentration of ozone
1910 10ppb
2000 20-30ppb
In Stratosphere• Good ozone• Decrease in protective
zones
Ozone Twin Problem
Pushing the ecosystem to the brink. Where it resides, it can protect or harm life.
Ozone hole in the stratosphere
Effect of ozone on forest ecosystem
• May alter sensitive plant species in forests• Reduces nutrient levels• Changes mortality rates of plant species• Other ecological impacts not known?
Research on ozone effects on forest trees
Plays a role in the decline of• Ponderosa pine in California• Red spruce in N. Appalachians• Pitch pine in New Jersey• Yellow pine in Southern US
Recent Developments...
• Montreal Protocol Amended in 1990 signed by 36 nations called for a phasing out of CFCs, halons, and other forms of precursors by the year 2000.
Recent Developments...
Amendments to the Clean Air Act in 1990
-EPA is responsible for setting guidelines
-Catalytic converter in vehicles to reduce pollution
-Use of devices in factories, power plants, homes
-Reduce use of plastics and CFC’s products
Clean Air Act Amendments
1990
Recent Developments
Environmental problems are now more diverse and on a larger scale than ever
before experienced
NC awareness & ozone action days?
Provide information on air pollution, its causes and effects
CodePurple
Unhealthy
Code Orange
Approaching
unhealthy
Ozone pollution in North Carolina• 22 of the 23 counties monitored violate the
state ozone pollution standard• Last June Charlotte recorded dirtiest air in
U.S.• Greatest impact on children with asthma • Coal burning power plants- largest single
source
Concept mapUV
radiationAtmosphereOxygenOzoneStratosphereozone layerOzone holeSkin cancerPlant damageTroposphereCFC’sNitrogen oxidesVOC’sSmog
Summary of ozone concepts
• Ozone is a molecule of three oxygen atoms• Ozone is broken apart by the sun’s UV radiation• Ozone is destroyed by catalytic processes e.x. Cl,
NOx, Br or hydrogen
• The ozone hole is a result of man’s activities• International agreements regulated the use of CFCs
& other pollutants• The harmful effects of ozone on the ecosystem
Student: Teacher, every time I drink coffee I get a stab in my left eye
Teacher: Take the spoon out of the cup.
KEY
Condition
Changing Capacity
Environmental Scorecard
Our ideals, laws and customsshould be based on the propositionthat each generation in turn becomesthe custodian rather than the absolute owner of our resources… and eachgeneration has the obligation to pass this inheritance on to the future
-Alden Whitman
For making an impact
Who Moved My Cheese?
“Things that matter most must never be at the mercy of things that matter least.” Goethe