Variation of effective attachment coefficient with pollution and its effect on atmospheric electric parameters over the Indian subcontinent

摘要

A comprehensive model is developed for the calculation of effective attachment coefficient β_(eff) for polluted and unpolluted atmospheres. It is found that β_(eff) depends significantly on the aerosol size distribution. These calculated values of β_(eff) are then used to calculate the various atmospheric electric parameters, viz. conductivity, air-earth current, electric field, and potential over the Indian subcontinent taking into account the earth's orography in 0.5° grid in latitude and longitude as well as the production of small ions due to cosmic rays and radioactivity. The electric parameters are found to increase with the latitude and the altitude of the ground. However, the latitudinal effect is very small compared to the orographic effect. The average electric field is nearly 98 V/m over land and 136 V/m over ocean. The electric field and potential are maximum while the conductivity is minimum during winter. With increase in pollution, current density and conductivity are found to decrease, whereas electric field and potential increase.