ap environmental science ch. 19, part 4 ozone depletion

APES Plans for the week of January 25th through January 29th, 2016 Monday 1-25-16: Ishmael Intro, Ozone notes Tuesday 1-26-16: Ishmael class discussion and reflective essay Wednesday 1-27-16: AIR EXAM Ch. 7, 18, 19 Thursday 1-28-16: Ch. 8 Aquatic Biodiversity Notes Friday 1-29-16: Videos on human impact on aquatic ecosystems Homework: STUDY for your EXAM. You may use 1 3x5 notecard. You must turn in the notecard. Bring water for lab, read book 2 in Ishmael

Today

1. Ishmael intro2. Ozone notes – short! 3. Ozone FRQ – you can work together

1. Sentences, yo2. Details, PLEASE3. NO TECHNOLOGY or you take a zero

The Ozone LayerThe Ozone Layer

Ch. 19, part 5Ch. 19, part 5

Some really big holes

Mir Diamond Mine, SerbiaMir Diamond Mine, SerbiaThis hole is so big that it sucked several helicopters into it and caused crashes. Its not officially the biggest mine in the world, but it is often touted as such.


Dean’s Blue Hole, BahamasDean’s Blue Hole, BahamasThis blue hole near the Bahamas is 663 ft feet deep. It’s the deepest blue hole in the world. Blue holes were formed about 15,000 years ago when the ocean level was lower. The average blue hole depth is about 300 feet, so this one is pretty deep.


Kola Superdeep BoreholeKola Superdeep BoreholeThe USSR set up a project to just dig as deep as they possibly could into the ground. After 19 years, they had dug more than 40,000 feet straight down into the earth. The mud that was coming up toward the bottom was boiling with hydrogen gas.


Guatemala SinkholeGuatemala SinkholeFrom an eroding pipe system, this sinkhole is 204 feet deep. Unfortunately three people were killed when their house fell into it.


The Gates of HellThe Gates of HellThis isn’t really a big hole, but definitely an intense one. In the Karakum desert near Turkmenistan, a Soviet drilling rig accidentally punctured a gas pocket and caused the ground to collapse. To avoid dumping the gas into the atmosphere, the Soviets decided to set it on fire, and the hole has burning for the last 38 years.


The Hole in the Ozone LayerThe Hole in the Ozone LayerLast year, the hole in the ozone layer was 27 million square kilometers. That’s the biggest hole on the planet by far.

The Ozone LayerThe Ozone Layer• Layer in

stratosphere• Blocks out 95%

of UV radiation

• In 1984, scientists found that about 1/2 the ozone over Antarctica (100% in some areas) disappears in the fall

• Ozone depleted air flows north over Australia, South America, South Africa

• Raises UV levels by 3-20%• Similar, though less intense

thinning over the arctic. This air flows over Europe, North America, and Asia

Antarctic - Antarctic - south polesouth pole

Arctic - north Arctic - north polepole

hihi

CFCsCFCs• Chloroflurocarbons• Odorless, nonflammable, nontoxic,

noncorrosive, unreactive• Used as coolants in air conditioners,

propellants in aersol cans

Too good to be true• Persistent

chemicals• Destroy the

ozone layer

Other harmful chemicals

• Halons & HBFCs (hydrobromoflurocarbons) - fire extinguishers

• Methyl bromide (soil fumigant)

• Hydrogen chloride (space shuttle)

• Carbon tetrachloride, hexachlorobutadiene (cleaning solvents)

So what?• 3-20% more UV radiation reaches the

surface of the earth

So what?• Eye cataracts• Sunburn• Skin cancer• Kills phytoplankton• Less upwelling, so less plankton

So what?

• Decreased photosynthesis decreased crop yield

What we can do• Stop using ozone depleting

chemicals– Should take ozone layer ~ 60

years to recover– Montreal Protocol - 1987 - 36

nations met to cut CFC emissions

– Copenhagen Protocol - 1992 - 92 nations agreed to phase out ozone depleting chemicals

• Now 191 countries on board

This is a success story we can be proud of

1. Convincing scientific evidence of a serious problem

2. CFCs only used by a few international companies

3. Private sector encouraged to find good alternatives

ap environmental science ch. 19, part 4 ozone depletion

Education