Sequential sampling and variability of acid precipitation in Hampton, Virginia

✍ Scribed by G. L. Pellett; Roberta Bustin; R. C. Harriss

• Book ID: 104650484
• Publisher: Springer Netherlands
• Year: 1984
• Tongue: English
• Weight: 937 KB
• Volume: 21
• Category: Article
• ISSN: 0049-6979
• DOI: 10.1007/bf00163610

✦ Synopsis

Rain samples were collected sequentially by amount ( ~ 2.7 mm each) from individual events at a single, relatively isolated, suburban site from August 1977 to July 1980. Rain pH's for < 3 mm samples closely fit a monomodal Gaussian distribution with a median of 4.50 and a standard deviation of 0.39. The variability in pH was primarily interevent as opposed to intraevent. The 3-yr volume-weighted pH was 4.35 + 0.02 for 3.16 m collected; annual pH's were 4.31,4.37, and 4.38, and cumulative H + deposition was 141 mg H + m -2. Event-averaged rain pH and meteorological and air quality data were correlated. Low pH was associated with low rainfall volume and rate; rain after several dry days; rains with northeast surface winds; high SOz, NO2, and 03 in the ambient atmosphere; and high, strongly correlated, SO 4 and NO;rainwater concentrations. The lowest 3-yr seasonal average pH (4.31) occurred during summer; values for other seasons were ~ 4.37. Average intraevent H + molarity (volume-weighted) was accurately characterized by 6.89 E -5 *(mm rain) o.z15 The relative merits of composite (e.g., whole event) and sequential sampling are examined.