Abstract
A microprocessor-based acid rain monitor was used to make real-time measurements of conductivity and pH of rainwater within individual storms. The automated measurements were compared with laboratory analyses of a subset of the samples taken. The laboratory measurements tended to overestimate the pH because of temperature induced changes in dissociation and Henry's Law constants affecting ionic compounds in the rainwater. The measurement artefact due to these effects may result in average hydrogen ion concentrations being underestimated by approximately 10 to 15% at UK sites. The greatest systematic discrepancies would be anticipated at highly polluted sites and during low temperature acidic episodes. The concept of a rainwater acid fraction was investigated and found to be useful for quality control and interpretative purposes. The field measurement of conductivity of low ionic strength samples was slightly lower than the corresponding laboratory measurement, possibly caused by limited resolution of the conductivity probe or dissolution of fine particulate material.
Similar content being viewed by others
References
Ames, D. L., Roberts, L. E. and Webb, A. H.: 1987, Atmospheric Environment 21, 1947.
Barrie, L. A.: 1978, Atmospheric Environment 12, 407.
Bates, R. G.: 1973, Determination of pH: Theory and Practice, John Wiley and Sons, New York.
Beverland, I. J., Crowther, J. M. and Srinivas, M. S. N.: 1996, Episodic Deposition of Acid Material at a Site in SE England', Presented at 5th International Conference on Acid Deposition, Gotenberg, Sweden, 26-30th June. Accepted by Water, Air and Soil Pollution.
Berverland, I. J. and Crowther, J. M.: 1992, Environmental Pollution 75, 163.
Brennan, C. J. and Peden, M. E.: 1987, Atmospheric Environment 21, 901.
Brimblecombe, P.: 1986, Air Composition and Chemistry, Cambridge University Press, London.
Cape, J. N.: 1988, Personal Communication, Institute of Terrestrial Ecology, Bush Estate, Penicuik, Scotland.
Cape, J. N. and Fowler, D.: 1986, Water, Air, and Soil Pollut. 30, 239.
Charlson, R. J. and Rodhe, H.: 1982, Nature 295, 683.
Cooksey, B. G.: 1988, Personal Communication, Department of Chemistry, University of Strathclyde, Glasgow, UK.
Davies, T. D., Abrahams, P. W., Tranter, M., Blackwood, I., Brimblecombe, P. and Vincent, C. E.: 1984, Nature 312, 58.
de Pena, R. G., Walker, K. C., Lebowitz, L. and Micka, J. G.: 1985, Atmospheric Environment 19, 151.
Fowler, D. and Cape, J. N.: 1984, Atmospheric Environment 18, 1859.
Galloway, J. N., Likens, G. E., Keene, W. C. and Miller, J. M.: 1982, Journal of Geophysical Research 87, 8771.
Gardener, M. J.: 1984, The Determination of pH in Poorly Buffered Waters, Recommendations of a meeting at WRC, Medenham, April 1984, WRC Environment, Medenham Laboratory, UK, Medenham, UK.
HMSO (1978) The Measurement of Electrical Conductivity and the Laboratory Determination of the pH Value of Natural, Treated and Waste Waters, Methods for the examination of waters and associated materials. HMSO, London.
Keene, W. C. and Galloway, J. N.: 1984, Atmospheric Environment 18, 2491.
Koch, W. F., Marinenko, G. and Stolz, J. W.: 1982, Simulated Reference Materials, IV. National Measurements Laboratory, Inorganic analytical research division, Washington D. C., USA.
Koch, W. F.: 1986, Standard reference materials:methods and procedures used at the National Bureau of Standards to prepare, analyse and certify SRM2694, simulated rainwater, and recommendations for use. US Department of Commerce/National Bureau of Standards, Washington D. C., USA.
Kronmiller K. G. and Ellenson, W. D.: 1990, Atmospheric Environment 24A, 525.
Laquer, F. C.: 1990a, Atmospheric Environment 24A, 2289.
Laquer, F. C.: 1990b, Atmospheric Environment 24A, 2299.
Marsh, A.: 1989, Personal Communication, National Power Technology and Environment Centre, Leatherhead, UK.
Metcalf, R. C.: 1984, Analyst 109, 1225.
Miller, R. L. and Kahn, J. S.: 1962, Statistical Analysis in the Geological Sciences, John Wiley and Sons, New York.
Peden, M. E.: 1983, ‘Sampling, Analytical and Quality Assurance Protocols for the National Atmospheric Deposition Program’, in S. A. Campbell (ed.) Sampling and Analysis of Rain, pp. 72–83.
Peters, K. and Klemm, O.: 1989, Atmospheric Environment 23, 1157.
Reddy, M. M., Liebermann, T. D., Jelinski, J. C. and Caine, N.: 1985, Artic Alpine Research 17, 79.
RGAR: 1987, Acid Deposition in the U. K. 1981-1985, Second report of the UK Review Group on Acid Rain, Warren Spring Laboratory, Stevenage, UK.
Stumm, W. and Mogan, J. J.: 1996, ‘Aquatic Chemistry’, 3rd. ed., Wiley-Interscience.
Schroder, L. J., Linthurst, R. A., Ellson, J. E. and Vozzo, S. F.: 1985, Water, Air and Soil Pollut. 24, 177.
Sisterson, D. L. and Wurfel, B. E.: 1984, International Journal of Environmental and Analytical Chemistry 18, 143.
Srinivas, M. S. N.: 1989, ‘The Development of a Microprocessor-Based Acid Rain Monitor and its Application to the study of acid Precipitation Events’, Phd Thesis, Department of Physics and Applied Physics, University of Strathclyde, Glasgow, UK.
Warneck, P.: 1986, ‘The Equilibrium Distribution of Atmospheric Gases Between Two Phases of Liquid Water Clouds’, in W. Jaeschke (ed.) Chemistry of Multiphase Atmospheric Systems, NATO ASI Series Vol. G6. Springer-Verlag, pp. 473–499.
Winkler, P.: 1980, Journal of Geophysical Research 85, 4481.
Winkler, P.: 1982, ‘Deposition of acid in precipitation’, in H. W. Georgii and J. Pankrath (eds.), Deposition of Atmospheric Pollutants, Reidel Publ. Co. Dordrecht, Netherlands, pp. 67–76.
Winkler, P.: 1984, ‘Observations on Acid Particles and Droplets in the Atmosphere’, in J. L. Durham (ed.) Chemistry of Particles. Fogs and Rain. (Acid precipitation series - Volume 2) Butterworth Publishers, Boston, pp. 161–196.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Beverland, I.J., Heal, M.R., Crowther, J.M. et al. REAL-TIME MEASUREMENT AND INTERPRETATION OF THE CONDUCTIVITY AND pH OF PRECIPITATION SAMPLES. Water, Air, & Soil Pollution 98, 325–344 (1997). https://doi.org/10.1023/A:1026407027848
Issue Date:
DOI: https://doi.org/10.1023/A:1026407027848