Data to be collected for this project

Improve measurement of dry deposition of N, especially gaseous NO2, NH3. At least 1/3 of the measured total N

deposition at the sites is in theform of dry deposition, but not all components have been measured yet.

MARGA (Monitoring instrument for aerosols and gases; see box at left) hourly sampling for gaseous NH3, HNO3, and

HNO2, and particulate NH4+ and NO3

-; ThermoElectron 42C-

Y chemiluminescence detector for hourly sampling for NOy

Passive gas sampler monitoring for dry deposition of NH3,

NO2, NOx, HNO3

Comparison of data from passive samplers and CASTNet filter packs

Further tests of spatial variability of dry deposition components

Agricultural Ecology Program: Understanding sources and sinks of

nutrients and sediment in the upper Susquehanna River basin

Connecticut Hill Atmospheric and Precipitation Chemistry Research and Monitoring Facility

Measuring Atmospheric N Inputs

The site is one of the longest operating wet and dry deposition sites in the U.S. Designed to be regionally representative, the 6 ha site is located near the 4500 ha NYS Conn. Hill Game Management Area. Both the landscape and land use are typical of other headwater sections of the Susquehanna River watershed in New York State.

NOx emissions impacting area

National Atmospheric Deposition Program (NADP/AIRMoN Site NY67)

Daily precipitation chemistry for NO3- and NH4

+ as well as other ionic species

Clean Air Status and Trends Network (CASTNet) Site CTH 110

NOx Emissions, 31 Eastern States

0

2

4

6

8

10

12

14

16

18

19911992

19931994

19951996

19971998

19992000

2001

NO

x E

mis

sio

ns

(mill

ion

met

ric

ton

s)

Other 20.2%

Electric 25.4%

Vehicle 54.4%

Total

NO3- (μeq/L)

y = -0.3775x + 778.9

R2 = 0.575

0

5

10

15

20

25

30

35

40

1975 1980 1985 1990 1995 2000 2005

Precipitation (cm)

y = 0.4463x - 780.81

R2 = 0.0522

0

20

40

60

80

100

120

140

160

1975 1980 1985 1990 1995 2000 2005

NH4+ (ueq/L)

y = -0.0079x + 31.833

R2 = 0.0012

0

5

10

15

20

25

1975 1980 1985 1990 1995 2000 2005

Cooperative State Research, Education, and Extension Service

Marga Sample Data: Diurnal Variation at Beltsville, MD

0

0.5

1

1.5

2

2.5

1 3 5 7 9 11 13 15 17 19 21 23

hourly pattern, 16-18 June 2005

ug/m

3

HCl

HNO2

HNO3

NH3

MARGA Output (also measures particulate NH4

+ and NO3-)

Weekly drydepositionincludinggaseous HNO3

& particulateNO3

- and NH4+