Associate Professor, Teppei J. Yasunari, of our center (ARC, Hokkaido University) installed a portable PM2.5 measurement system for cold regions at the Snow and Ice Research Center (SIRC) of the National Research Institute for Earth Science and Disaster Resilience (NIED) in Nagaoka City Niigata Prefecture on November 1, 2021. This collaborative research with NIED/SIRC is based on a long-term joint research plan: “Observational study on temporal variation of the effect of PM2.5 on snowfall in the Hokuriku region” (the joint research agreement signed on October 25, 2021) for a minimum of five years, analyze the validity of the data, and consider successor research. In the SIRC, they will analyze, for example, the relationship between quantitative changes of PM2.5 and snow cover characteristics by comparing PM2.5 observations with precipitation, snow particle characteristics, snow surface albedo, long and shortwave radiation. On the other hand, ARC is in charge of comparing measured PM2.5 data at SIRC with those at multiple different locations deployed by ARC, discussing large-scale atmospheric circulation patterns. Our center also analyzes the origin and path of atmospheric aerosols affecting the measured PM2.5 data and the meteorological characteristics that determine their characteristics.