envierment
News
https :// www.enn.com/articles/69020-researchers-uncover-genetic-goldmine-underlying-plant-resilience-in-extreme-desert-environment
https:// www.bbc.com/news/science-environment-59088498
https:// www.bbc.com/news/science-environment-59078198
https:// www.npr.org/2021/10/29/1045344199/cop26-glasgow-climate-summit
https:// phys.org/news/2021-11-atmospheric-detergent-climate.html
Stratospheric Ozone
75% of Mass
below
17 km
>390 nm
200-300 nm
5500 m—0.5 bar
(18,000 feet)
2000 m—0.8 bar
Global Warming: Warm Blanket, low
Ozone Depletion: Thin filter, high
What are the biggest impacts of ozone depletion?
A) Warming of lower troposphere
B) Disinfection of sewage by chlorine
C) Increased incidence of skin cancer
D) Increased incidence of asthma
E) Increases in lung cancer
Light
Sunlight Spectrum
UVA=320-400 nm
UVB=280-320 nm
UVC=<280 nm
Ozone
Greenhouse Gases
Stratospheric vs. Tropospheric Ozone
Ozone Depletion
Production of Ozone
O2 + hv (<240 nm) O + O
O + O2 O3
O3 + hv (<290 nm) O2 + O
Destruction of Ozone
O3 + O 2O2 (Naturally slow)
O3 + Cl O2 + ClO
ClO + O O2 + Cl
O3 + O 2O2 (Catalytically fast)
Cl can catalyze destruction of O3 100,000 times
Freons completely inert
10-20 year lag in troposphere
65-135 year residence time in stratosphere
Antarctic Ozone Hole
5% loss in O3 500% increase at 287 nm
Polar Stratospheric Clouds (PSC)
Antarctic Spring
Polar Vortex
Stratospheric clouds made of ice (nitric acid)
Sunlight initiate reactions
Heterogeneous chemistry (on particles)
Breakout Groups
How can we solve this problem?
Regulations
Solved? By 2050
Hydro Halocarbons (HFCs)
Single manufacturer (Dupont)
Scientific consensus
Simple chemistry