Ground based in situ observations of particle_number_size_distribution at Pallas (Sammaltunturi) (FI0096G) using dmps. These measurements are gathered as a part of the following projects CREATE, EMEP, EUSAAR, GAW-WDCA and they are stored in the EBAS database (http://ebas.nilu.no/). Parameters measured are: particle_number_size_distribution in pm10