Acid Rain How does it form?Where is this a problem?What does it do to ecosystems and people?

Acid Deposition formation:Secondary or primary pollutant?Sources for precursors?Transportation? Wet or dry deposition?

Formulas you need to memorize:

SO3 + H2O H2SO4 (sulfuric acid)

NOx + H2O 2HNO3 (nitric acid)

These are two forms (flavors) of acid deposition.

Normal rain

CO2 + H2O H2CO3 (carbonic acid)

Normal rain is always slightly acidic!

THIS IS NOT ACID RAIN!!!THIS IS NOT POLLUTION!!!!

Acid rain < pH 5.6

OBSERVATIONS? IS ACID RAIN A BIG PROBLEM IN HOUSTON?WHERE IS ACID RAIN A BIG CONCERN?

Global acid rain areas of concern

Effects on terrestrial systems:

Direct damage to leaves and roots

Weak trees are susceptible to insects and disease

Acid deposition leaches nutrients from soil and makes toxins (Al3+) more soluble

Effects on Aquatic ecosystems

Loss of biodiversity Range of tolerance Jelly-like fish eggs broken down Acidity denatures enzymes

Acid shock – sudden increase in acidity, often in spring can cause fish kills

Aluminum ions (Al3+) are released from lake bed, suffocating fish

Below pH4.5, lakes devoid of fish

Cultural effects of acid rain

Marble and limestone Acid breaks down these basic materials

Many famous buildings are being damaged

Taj Mahal Parthenon

Statue of liberty Loss of artistic detail in Acropolis

Human health effects of acid rain

Contributes to bronchitis and asthma

Acid Rain: Check for understanding!

How does acid rain form? What is the pH of acid rain? Why is rain normally acidic? Why is this a bigger problem on the East Coast

than here? Why is acid rain “like AIDS for plants”? Why are there more significant effects on aquatic

systems than on terrestrial systems?

IF YOU’RE NOT PART OF THE SOLUTION, YOU’RE PART OF THE

PRECIPITATE.

Solutions to Air pollution

1994

1999

2007

Two strategies

Pollution prevention (don’t create the primary pollutants in the first place)

Pollution clean up (now that they’re in the environment, let’s mitigate the effects)

Legal solutions

Emissions trading policy (Cap and Trade): stationary pollution sources can buy, sell and trade the right to pollute.

This policy ONLY exists in the US for SOx right now.

(CO2 cap and trade just started in California last year!)

Technology Strategies: trap pollutants at the source

Technology solution: improved vehicle efficiency

Using less gas = fewer combustion pollutants

Hybrids use friction from breaking to charge electric battery “regenerative breaking”

Computer switches engine from gas to electricity.

CHEVY VOLT 2011 – POLLUTION DIVERTED TO POWER PLANT

Technology solution: burn cleaner coal/coal gasification

Burn low-sulfur coal from Western US

Gasification turns solid coal to gas before it is burned – fewer particulates, SOx

“LIMING” A LAKE (POWDERED LIMESTONE)

Stream doser

Spot the pipe which adds the limestone solution to the stream!

I=PAT

I = clean air P = growing A = options? T = options?

Which of these can YOU do TODAY?