For the primary formation of ice crystals in clouds in the temperature range between 0°C and roughly -38°C, catalysts are needed which can initiate the nucleation of ice in a liquid, supercooled drop. Atmospheric particles that can act as such catalysts are called ice nucleating particles (INP).
Atmospheric concentrations of INP have been determined by TROPOS in a series of measurement campaigns at various locations around the world. Atmospheric filter samples were collected and evaluated in the laboratory. Off-line instrumentations were used, which can provide data in the temperature range from 0°C to approx. -25°C (the statements below therefore generally refer to this temperature range).
The obtained data are among others important input parameters for climate models and can help to improve future model calculations.
The following investigations and observations were made:
- Zypern: Filter samples were collected both in the framework of a joint INUIT/BACCHUS-campaign (April 2016) as well as during A-LIFE (April 2017).