ON THE ROLE OF SULFATE ION IN THE ATMOSPHERE

Drop freezing experiments with ammonium sulfate water solutions have shown the existence of the temperature maxima that are a function of the salt concentration.The maxima were:-12℃ for 10-4 M solution on filter,-9℃ for 10-4 to 10-3M solution in contact with particles of continental origin,and-4℃ for 10-4 M solution in contact with particles of marine origin.It was speculated that the presence of ice-forming nuclei active at high temperature(-4℃） should extend the formation of ice in clouds toward lower latitudes,increase their albedos,and provide additional cooling during daytime for the earth.The microphysics of clouds must be included in studying climate.