Summertime nitrous acid chemistry in the atmospheric boundary layer at a rural site in New York State

[1] Ambient measurements of HONO and HNO3, using a highly sensitive coil scrubbing/HPLC/visible detection technique, were made at a rural site in southwestern New York State from 26 June to 14 July 1998, along with concurrent measurements of NOx, NOy, O3, and various meteorological parameters. The mean (and median) half-hour concentrations of HONO and HNO3 during this period were 63 (and 56) pptv and 418 (and 339) pptv, respectively. On average, there were two HONO concentration peaks, the first around 0200–0300 LT and the second around 0700–0800 LT, and a minimum at about 2000 LT. The sum of NOx, HONO, and HNO3 (ΣNOyi) was highly correlated with the measured NOy concentration (r2 = 0.64). The average HONO/NOx ratio was 0.07, while the average ΣNOyi/NOy ratio was 0.66. During the early morning hours, the photolysis of HONO appeared to be a dominant source of HOx radicals in boundary layer near the ground surface. The average daily radical production from HONO photolysis was 2.3 ppbv, accounting for 24% of the total production from photolyses of HONO, O3, and HCHO at the measurement height of 4 m above the ground. Diurnal patterns of HONO and relative humidity suggest that the ground and vegetation surfaces were sinks for HONO in the boundary layer when dew droplets were formed at night and that the subsequent release of the trapped nitrous acid/nitrite from the surfaces acted as a strong HONO source in the morning as the dew droplets evaporated. Our data also suggest that, in order to maintain the observed daytime HONO concentration of ∼60 pptv, there should be a strong daytime source of 220 pptv hr−1, which was much greater than the nighttime source of 13 pptv hr−1 and the estimated production of ∼ 40 pptv hr−1 from the gas-phase NO-OH reaction. Photolysis of HNO3, which deposits and accumulates on the ground and vegetation surfaces, may contribute significantly to the “missing” daytime HONO sources.

[1]  Xianliang Zhou,et al.  A Method for the Measurement of Atmospheric HONO Based on DNPH Derivatization and HPLC Analysis , 1999 .

[2]  Xianliang Zhou,et al.  Method for the determination of some soluble atmospheric carbonyl compounds , 1993 .

[3]  A. Reisinger.  Observations of HNO2 in the polluted winter atmosphere : possible heterogeneous production on aerosols , 2000 .

[4]  B. Hicks,et al.  HNO3 deposition to a deciduous forest , 1989 .

[5]  Oliver Lindqvist,et al.  Kinetics of the reaction between nitrogen dioxide and water vapour , 1987 .

[6]  Gerhard Lammel,et al.  The atmospheric aerosol as a source of nitrous acid in the polluted atmosphere , 1988 .

[7]  A. Stohl.  Computation, accuracy and applications of trajectories—A review and bibliography , 1998 .

[8]  B. Huebert,et al.  The dry deposition of nitric acid to grass , 1985 .

[9]  P. Shepson,et al.  Snowpack photochemical production of HONO: A major source of OH in the Arctic boundary layer in springtime , 2001 .

[10]  A. M. Dunker,et al.  An evaluation of the mechanism of nitrous acid formation in the urban atmosphere , 1994 .

[11]  Xianliang Zhou,et al.  Photochemical production of nitrous acid on glass sample manifold surface , 2002 .

[12]  P. Wiesen,et al.  A new instrument to measure gaseous nitrous acid (HONO) in the atmosphere. , 2001, Environmental science & technology.

[13]  J. Bolton,et al.  Photochemistry of nitrite and nitrate in aqueous solution: a review , 1999 .

[14]  Shao-Meng Li.  Equilibrium of particle nitrite with gas phase HONO: Tropospheric measurements in the high Arctic during polar sunrise , 1994 .

[15]  R. Harley,et al.  Mathematical modeling and control of the dry deposition flux of nitrogen-containing air pollutants , 1993 .

[16]  J. Aber,et al.  The response of lake water in the Adirondack region of New York to changes in acidic deposition , 1998 .

[17]  U. Platt,et al.  Observations of nitrous acid in the Los Angeles atmosphere and implications for predictions of ozone-precursor relationships. , 1982, Environmental science & technology.

[18]  K. Civerolo,et al.  Measurements of atmospheric nitrous acid and nitric acid , 2002 .

[19]  U. Baltensperger,et al.  Heterogeneous production of nitrous acid on soot in polluted air masses , 1998, Nature.

[20]  Justus Notholt,et al.  A DOAS study on the origin of nitrous acid at urban and non-urban sites , 1996 .

[21]  P. Dasgupta,et al.  Measurement of ambient nitrous acid and a reliable calibration source for gaseous nitrous acid , 1991 .

[22]  Roy M. Harrison,et al.  Tropospheric cycle of nitrous acid , 1996 .

[23]  J. Dibb,et al.  Release of NOx from sunlight‐irradiated midlatitude snow , 2000 .

[24]  R. A. Cox,et al.  Evaluated kinetic and photochemical data for atmospheric chemistry: Volume III - gas phase reactions of inorganic halogens , 2006 .

[25]  L. Kleinman,et al.  Peroxy radical concentration and ozone formation rate at a rural site in the southeastern United States , 1995 .

[26]  Roger Atkinson,et al.  An Investigation of the Dark Formation of Nitrous Acid in Environmental Chambers , 1984 .

[27]  R. A. Cox,et al.  Evaluated kinetic and photochemical data for atmospheric chemistry: Supplement V , 1996 .

[28]  F. Fehsenfeld,et al.  Contribution of organic nitrates to the total reactive nitrogen budget at a rural eastern U.S. site , 1990 .

[29]  Gerhard Lammel,et al.  Nitrous acid and nitrite in the atmosphere , 1996 .

[30]  C. Perrino,et al.  Evaluation of a high-purity and high-stability continuous generation system for nitrous Acid. , 1995, Environmental science & technology.

[31]  James N. Pitts,et al.  Chemistry of the Upper and Lower Atmosphere: Theory, Experiments, and Applications , 1999 .

[32]  B. Huebert,et al.  Measurements of concentrations and dry surface fluxes of atmospheric nitrates in the presence of ammonia , 1988 .

[33]  W. Benjey,et al.  Analysis of ammonia and aerosol concentrations and deposition near the free troposphere at Mt. Mitchell, NC, U.S.A. , 1998 .

[34]  P. Shepson,et al.  Evidence of NOx production within or upon ice particles in the Greenland snowpack , 1999 .