Research Organization of Information and Systems
Clouds, composed of tiny water droplets or ice crystals, play a vital role in regulating Earth’s climate by influencing the amount of solar radiation that reaches the surface. The cloud phase significantly impacts the surface energy balance as liquid water clouds reflect more radiation than ice clouds. Ice clouds typically form at temperatures below −38°C, but recent observations indicate their formation at higher temperatures in the Arctic. This phenomenon is facilitated by ice-nucleating particles (INPs), including mineral dust, organic aerosols and bioaerosols, which promote ice cloud formation above the usual freezing point.
These INPs, primarily sourced from outsude of the Arctic refion, also include traces of organic carbon (OC) aerosols. Wildfires in Canada, Alaska, and Russia are major sources of these aerosols, contributing to higher concentrations of OC, black carbon, and other aerosols over the Arctic. However, despite extensive scientific evidence of aerosol transport from lower latitudes, a clear link between the transported aerosols and ice cloud formation in the Arctic remains unestablished.
In a recent study led by Assistant Professor Kazutoshi Sato and involving Professor Jun Inoue from the National Institute of Polar Research, Japan, scientists set out to understand how wildfire aerosols influence ice cloud formation in the Arctic. The study was made available online on December 24, 2024 and is set to be published in Volume 315 of Atmospheric Research on April 1, 2025…