Chemical composition of monsoon rains over Calcutta. Part I

Abstract

Monsoon rainwater over Calcutta was analysed for Na, K, Ca, Mg, Cl, SO4, HCO3, NO3, pH, SiO2, B and Fe. The data shows that the dissolved mineral content is greatly affected by meteorological conditions viz. intensity, quantity and interval between various showers as well as wind velocity (cyclonic weather). Amongst the ions bicarbonate ions are quite prominent, particularly when rainfall is low. The sulphate ions generally exceed the chloride ions. The origin of the various constituents is also discussed.