1. Department of Earth and Planetary Science, Graduate School of Science; University of Tokyo; Tokyo Japan
2. Faculty of Science; Niigata University; Niigata Japan
3. Department of Environmental Science and Analytical Chemistry; Stockholm University; Stockholm Sweden
4. National Institute of Polar Research; Tokyo Japan
5. Institute of Atmospheric Sciences and Climate (ISAC)/Italian National Research Council (CNR); Bologna Italy
6. Droplet Measurement Technologies; Longmont CO USA
7. Alfred Wegener Institute; Potsdam Germany
8. Norwegian Institute for Air Research (NILU); Oslo Norway
9. Norwegian Polar Institute; Tromsø Norway