Acid PrecipitationAcid Precipitation

By Zephyr Dworsky and Lucille SchiffmanFall 2007

By Zephyr Dworsky and Lucille SchiffmanFall 2007

Rain water was collected and analyzed in hopes of determining a correlation between storm origin and rain acidity.

Normal rain is said to have a pH of 5.7. Any rain with a pH lower than 5.7 is considered acid rain.

In general, winds in North America travel from west to east, the Northeast gets higher amounts of acid rain because the storms have been absorbing precursor pollutants as it travels across the continent.

Rain water was collected and analyzed in hopes of determining a correlation between storm origin and rain acidity.

Normal rain is said to have a pH of 5.7. Any rain with a pH lower than 5.7 is considered acid rain.

In general, winds in North America travel from west to east, the Northeast gets higher amounts of acid rain because the storms have been absorbing precursor pollutants as it travels across the continent.

Storms that originated in the western portion of the United States tend to be the most acidic, based on storms in the fall of 2007.

Storms that originated in the western portion of the United States tend to be the most acidic, based on storms in the fall of 2007.

pH of Storms Traveling from Various Regions of the United States

0

1

2

3

4

5

6

7

1

Storm

Avera

ge p

H

West

South/Southwest

West/Southwest

Based on data for all of 2007, storms that traveled from the Southwest region of the United States tend to be the most acidic.

Although this does not agree with the results from Fall 2007, they share a portion of the storm track over the Midwest, where most of the United States’ pollution is created.

However, if the storm is large, the acid concentration is diluted and thus the results can be skewed.

Based on data for all of 2007, storms that traveled from the Southwest region of the United States tend to be the most acidic.

Although this does not agree with the results from Fall 2007, they share a portion of the storm track over the Midwest, where most of the United States’ pollution is created.

However, if the storm is large, the acid concentration is diluted and thus the results can be skewed.

pH of Storms Traveling From Various Regions

0

1

2

3

4

5

6

7

1

Storm

Avera

ge p

HWest

South

Southwest

South Southwest

West Southwest

Northwest

Northeast

Coastal

Consistent with the pH values obtained, storms that traveled from the West in the fall of 2007 have the highest amount of total free acid.

Consistent with the pH values obtained, storms that traveled from the West in the fall of 2007 have the highest amount of total free acid.

Total Free Acid of Fall 2007 Storms

6.56828E-06

6.14576E-071.37505E-06

0

0.000001

0.000002

0.000003

0.000004

0.000005

0.000006

0.000007

West South/Southwest West/Southwest

Storm

Tota

l F

ree

Aci

d

For all storms tracked in 2007, the storms that traveled from the West had the by far the most total free acid.

This is consistent with both the pH and total free acid data from the fall of 2007. However, the pH data from all of 2007 show that storms that traveled from the Southwest were the most acidic.

For all storms tracked in 2007, the storms that traveled from the West had the by far the most total free acid.

This is consistent with both the pH and total free acid data from the fall of 2007. However, the pH data from all of 2007 show that storms that traveled from the Southwest were the most acidic.

Total Free Acid of all 2007 Storms

0.060624825

9.57541E-06 4.66827E-05 7.82606E-06 1.9032E-06 1.83636E-05 8.28792E-06 5.84466E-06

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

Storm

Tota

l F

ree

Ac

id

Where do ions in acid rain come from?

Where do ions in acid rain come from?

Sulfate and nitrate ions are a byproduct from industries that burn fossil fuels, such as electric power generating plants and cars.

The high population of the Northeast as well as the industries in the Midwest contribute to sulfate and nitrate ions found in the rain collected and analyzed.

Chloride generally comes from NaCl found in oceans, but also in smaller concentrations in freshwater bodies.

Sulfate and nitrate ions are a byproduct from industries that burn fossil fuels, such as electric power generating plants and cars.

The high population of the Northeast as well as the industries in the Midwest contribute to sulfate and nitrate ions found in the rain collected and analyzed.

Chloride generally comes from NaCl found in oceans, but also in smaller concentrations in freshwater bodies.

The storm with the highest amount of chloride, seen in pink, formed over the Great Lakes, picking up chloride from the water.

The other storm with a large amount of chloride was a storm that traveled from the South/Southwest, but this was a storm of light rain and mist, which characteristically have higher ion concentrations.

The storm with the highest amount of chloride, seen in pink, formed over the Great Lakes, picking up chloride from the water.

The other storm with a large amount of chloride was a storm that traveled from the South/Southwest, but this was a storm of light rain and mist, which characteristically have higher ion concentrations.

Amount of Chloride Found in Acid Rain

0.0000

0.2000

0.4000

0.6000

0.8000

1.0000

1.2000

1.4000

1.6000

Storm

am

ou

nt

of

Ch

lori

de (

pp

m)

There appears to be no trend in nitrate concentration from the storms tracked. This is most likely because it is difficult to detect trends with so few data points.

However, once again, the misty/light rain storm that traveled from the South/Southwest had a higher nitrate concentration than other storms.

There appears to be no trend in nitrate concentration from the storms tracked. This is most likely because it is difficult to detect trends with so few data points.

However, once again, the misty/light rain storm that traveled from the South/Southwest had a higher nitrate concentration than other storms.

Amount of Nitrate Found In Acid Rain

0.0000

1.0000

2.0000

3.0000

4.0000

5.0000

6.0000

7.0000

Storm

am

ou

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of

Nit

rate

(p

pm

)

Storms that traveled from the South/Southwest area of the United States show a trend of higher sulfate concentration than storms that traveled from elsewhere.

The one storm that traveled over the Atlantic Ocean shows significantly less sulfate content.

Storms that traveled from the South/Southwest area of the United States show a trend of higher sulfate concentration than storms that traveled from elsewhere.

The one storm that traveled over the Atlantic Ocean shows significantly less sulfate content.

Amount of Sulfate Found in Acid Rain

0.0000

0.5000

1.0000

1.5000

2.0000

2.5000

3.0000

3.5000

4.0000

4.5000

Wes

t Sou

thwes

t

South

/Sou

thwes

t

Wes

t

Coast

al

Storm

am

ou

nt

of

Su

lfate

(p

pm

)

ConclusionConclusion Overall, it was found that storms originating in

the west were the most acidic. Also, as the sulfate and nitrate ion

concentrations increase, the pH of the sample decreases.

However, due to our small sample size, a definite trend was difficult to detect and the margin of error was high.

By continuing this research and getting additional information, such as storm type and size, a more definite conclusion could be reached about the correlation between acid rain and storm origin. This could help determine ways to eliminate the causes of acid rain.

Overall, it was found that storms originating in the west were the most acidic.

Also, as the sulfate and nitrate ion concentrations increase, the pH of the sample decreases.

However, due to our small sample size, a definite trend was difficult to detect and the margin of error was high.

By continuing this research and getting additional information, such as storm type and size, a more definite conclusion could be reached about the correlation between acid rain and storm origin. This could help determine ways to eliminate the causes of acid rain.