【LECTURE】A Newly Identified Sea Salt Aerosol Source In Polar Regions And Its Climate Impact

Speaker: Dr. Yang Xin, British Antarctic Survey

Time: 10:30-12:00, December 18

Venue: Lecture Hall 322, Qilian Building,West Campus at Chengguan


Sea salt aerosols, from the surface of seawater, play a very important role in global climate system, mainly due to their large natural emission sources and their presence as a very efficient cloud condensation nucleation that significantly influences the formation and development of clouds, and therefore has an important impact on the radiation balance of the entire Earth system. However, recent observations have shown that the polar sea ice surface is also a huge source of sea salt aerosols, which is generated by sublimating salty snow particles produced by blowing snow. Due to differences in the formation mechanism, sea salt aerosols from open water and sea salt aerosols from blowing snow have different particle spectral distributions (e.g., in size and number) and emission rates. Observations and simulations show that the sea salt particles produced by windblown snow are smaller and mainly in fine mode (< 200 nm in diameter); their number density is larger than the seawater sea salt density by several orders of magnitude, so their impact on the polar climate will be more significant. However, this natural source has not been considered by current climate models, so its climatic effects are not clear. In this report, I will review the latest research progress in this field and explain the physical mechanism of the production of sea salt aerosols by blowing snow, and then discuss the new issues and opportunities in this field.


Source: College of Civil Engineering and Mechanics