Recombination of small ions in the troposphere and lower stratosphere

Abstract

The current practice of treating ionic recombination in the lower atmosphere is in error in two respects: firstly the Thomson formula for the ter-molecular recombination coefficient does not represent the behaviour as accurately as commonly assumed: secondly the ter-molecular recombination coefficient (expressed in binary form) and the rate coefficient for the binary recombination of an isolated ion-pair are not additive. Computer simulated experiments are performed which should give the total recombination coefficient in the region below 40 km with some precision. It is shown that the recombination rate is not appreciably affected by inhomogeneity in the cosmic ray ionization. The equilibrium small ion number density profile is calculated and found to be in good agreement with the observed profile. It is inferred that the mixing ratio of the trace gas x which reacts with proton hydrates to form non-proton hydrates has an approximately constant value of 5 × 10-13 from 20 to 42 km. © 1982.